The present technology relates to a semiconductor device, a manufacturing method therefor, and an electronic apparatus, and more particularly, to a semiconductor device suitable to be used in case of dicing a plurality of stacked substrates, a manufacturing method therefor, and an electronic apparatus.
This application claims the benefit of Japanese Priority Patent Application JP 2015-152922 filed on Jul. 31, 2015, the entire contents of which are incorporated herein by reference.
In a wafer-level lens process of arranging a plurality of lenses in planar directions of a wafer substrate, requirements for shape accuracy and position accuracy at the time of forming the lenses are strict. Particularly, a degree of difficulty of a process of manufacturing a stacked lens structure by stacking wafer substrates is very high, and in a mass production level, stacking of three or more layers has not been realized.
With respect to a wafer-level lens process, up to now, various technologies have been contrived and proposed. For example, PTL 1 discloses a method of stacking wafer substrates by using a lens material itself as an adhesive at the time of forming lenses by filling through-holes formed in the substrates with the lens material.
PTL 1: JP 2009-279790 A
However, in case of dicing wafer substrates after the stacking of the wafer substrates, there is a problem in that chipping generated in each wafer substrate reaches a through-hole to cause breakage of a stacked lens structure.
The present technology has been made in view of the foregoing, and it is desirable to reduce influence of chipping in case of dicing a plurality of stacked substrates.
According to a first aspect of the present technology, there is provided a lens substrate comprising: a substrate having a through-hole; a lens disposed in the through-hole; and a groove disposed adjacent to the through-hole in a cross-section view.
According to the first aspect of the present technology, there is provided a method of manufacturing a semiconductor device, the method comprising: forming a through-hole in a substrate; forming a lens in the through-hole; and forming a groove adjacent to the through-hole in a cross-section view.
According to the first aspect of the present technology, there is provided an electronic apparatus comprising: a camera module including a stacked lens structure, the stacked lens structure including: a plurality of substrates, each substrate of the plurality of substrates including: a through-hole with a lens disposed therein; and a groove disposed adjacent to the through-hole in a cross-section view.
In addition, the effects described herein are not necessarily limited, but any of the effects of the present disclosure may be available.
Hereinafter, aspects (hereinafter, referred to embodiments) for embodying the present technology will be described. In addition, the description will be made in the following order.
The camera module 1A is configured to include a stacked lens structure 11 and a light-receiving device 12. The stacked lens structure 11 is configured to include five optical units in each of the horizontal and vertical directions, namely, to include a total of twenty-five optical units 13. The optical unit 13 is configured to a plurality of lenses 21 in one optical axis direction. The camera module 1A is a compound-eye camera module including a plurality of optical units 13.
As illustrated in
In addition, in
The camera module 1A of
In a stacked lens structure 500 illustrated in
Before the substrates 512 are adhered to each other, a layer of the resin 513 is formed on the entire front surface of each substrate 512. After that, the substrates 512 are adhered to each other, and next, the resin 513 is cured. Therefore, the adhered substrates 512 are fixed to each other.
However, when the resin 513 is cured, the resin 513 is curing-contracted. In case of the structure illustrated in
In addition, even after the stacked lens structure 500 formed by adhering the substrates 512 is diced and the camera module is formed by combining imaging devices thereto, as illustrated in
The stacked lens structure 11 of the camera module 1A is also formed by stacking a plurality of the lens-attached substrates 41 provided with the lenses 21.
In the stacked lens structure 11 of the camera module 1A, as a means for fixing the lens-attached substrates 41 provided with the lenses 21, used is a fixing unit entirely different from the stacked lens structure 500 of
Namely, the two lens-attached substrates 41 which are to be stacked are directly joined to each other by covalent bonds between a surface layer of an oxide or a nitride formed on a surface of the one substrate and a surface layer of an oxide or nitride formed on a surface of the other substrate. As a specific example, as illustrated in
In this specification, in this manner, fixing of the two lens-attached substrates 41 through an inorganic film disposed between the two lens-attached substrates 41, fixing of the two lens-attached substrates 41 by chemically bonding inorganic films disposed on the surfaces of the two lens-attached substrates 41, fixing of the two lens-attached substrates 41 by forming bonds according to dehydration condensation between inorganic films disposed on the surfaces of the two lens-attached substrates 41, fixing of the two lens-attached substrates 41 by forming covalent bonds through oxygen or covalent bonds between elements included in inorganic films between the inorganic films disposed on the surfaces of the two lens-attached substrates 41, or fixing of the two lens-attached substrates 41 forming silicon-oxygen covalent bonds or silicon-silicon covalent bonds between silicon oxide layers or silicon nitride layers disposed on the surfaces of the two lens-attached substrates 41 are referred to as direct joining.
In order to perform the adhesion and the dehydration condensation by increasing temperature, in the embodiment, substrates used for a semiconductor device or a flat display device are used, lenses in a substrate state are formed, adhesion and dehydration condensation by increasing temperature are performed in a substrate state, and joining by covalent bonds is performed in a substrate state. Due to the structure obtained by joining the inorganic films formed on the surfaces of the two lens-attached substrates 41 by the covalent bonds, it is possible to obtain a function or an effect that deformation of the resin 513 over the entire substrates by curing-contraction or deformation of the resin 513 by thermal expansion in actual use, which is are problems in case of using the technology described with reference to FIG. 2 disclosed in PTL 1, is suppressed.
First, as illustrated in
Next, as illustrated in
Next, the substrate-state sensor substrate 43W and the substrate-state stacked lens structure 11W are stacked, and an external terminal is connected to each module of the adhered substrates, so that the substrate-state camera module 44W is obtained.
Finally, the substrate-state camera module 44W is diced in units of a module or a chip. The diced camera module 44 is sealed in a case (not shown) which is separately prepared, so that the camera module 44 as a final product is obtained.
In addition, in this specification and drawings, components such as the lens-attached substrate 41W of which reference numerals are attached with “W” denote that the components are in the substrate state (wafer state), and components such as the lens-attached substrate 41 of which reference numerals are not attached with “W” denote that the components are in the state that the components are diced in units of a module or a chip. These notations are similarly applied to the sensor substrate 43W, the camera module 44W, and the like.
First, similarly to the above-described process, the substrate-state stacked lens structure 11W where a plurality of substrate-state lens-attached substrates 41W are stacked is manufactured.
Next, the substrate-state stacked lens structure 11W is diced.
In addition, separately from the substrate-state stacked lens structure 11W, the substrate-state sensor substrate 43W is manufactured and prepared.
Next, the diced stacked lens structure 11 is mounted one by one on each light-receiving device 12 of the substrate-state sensor substrate 43W.
Finally, the substrate-state sensor substrate 43W where the diced stacked lens structure 11 is mounted is diced in units of a module or a chip. The diced sensor substrate 43 where the stacked lens structure 11 is mounted is sealed in a case (not shown) which is separately prepared, and an external terminal is further connected thereto, so that the camera module 44 as a final product is obtained.
In addition, as an example of another process of forming the camera module 1A of
As illustrated in
In the camera module 1A, the optical axes of a plurality of the optical units 13 are disposed so as to spread toward the outside of the module, so that it is possible to capture a wide-angle image. In
The lens-attached substrate 41W illustrated in
The substrate-state lens-attached substrates 41W illustrated in
It can be understood that, among the lens-attached substrates 41W illustrated in
The camera module 1B is configured to include two optical units 13. The two optical units 13 are provided with an aperture stop plate 51 on the uppermost layer of the stacked lens structure 11. Aperture portions 52 are installed in the aperture stop plate 51.
Although the camera module 1B includes the two optical units 13, the two optical units 13 have different optical parameters. Namely, the camera module 1B includes two types of optical units 13 having different optical performance. The two types of the optical units 13 may be, for example, a short-focal-length optical unit 13 for imaging a near view and a long-focal-length optical unit 13 for imaging a distant view.
In the camera module 1B, since the optical parameters of the two optical units 13 are different, for example, as illustrated in
The lens-attached substrate 41W illustrated in
The substrate-state lens-attached substrates 41W illustrated in
As illustrated in
The camera module 1C is configured to include two optical units 13 in each of the horizontal and vertical directions on a light incident surface, namely, to include a total of four optical units. Among the four optical units 13, the shapes of the lenses 21 are set to be the same.
Although the four optical units 13 have the aperture stop plates 51 on the uppermost layer of the stacked lens structure 11, the sizes of the aperture portions 52 of the aperture stop plates 51 are different among the four optical units 13. Therefore, with respect to the camera module 1C, it is possible to implement, for example, the following camera module 1C. Namely, for example, in a surveillance camera for crime prevention, in a camera module 1C using a light-receiving device 12 including light-receiving pixels for daytime color image surveillance which are provided with three types of R, G, and B color filters to receive three types of R, G, and B light beams and light-receiving pixels for nighttime black-and-white image surveillance which are not provided with R, G, and B color filters, with respect to only pixels capturing white-and-black images in the nighttime when illuminance is low, the size of the aperture of the aperture stop can be increased. For this reason, for example, the planar shape of the lenses 21 in the one camera module 1C is configured so that, as illustrated in
The substrate-state lens-attached substrates 41W of
As illustrated in
Similarly to the camera module 1C, the camera module 1D is configured to include two optical units 13 in each of the horizontal and vertical directions on a light incident surface, namely, to include a total of four optical units. Among the four optical units 13, the shapes of the lenses 21 and the sizes of the aperture portions 52 of the aperture stop plates 51 are set to be the same.
The camera module 1D is configured so that the optical axes of the two optical units 13 disposed in each of the horizontal and vertical directions of the light incident surface extend in the same direction. The one-dotted dash lines illustrated in
In the camera module 1D, while the optical axes in each of the horizontal and vertical directions are directed toward the same direction, images can be captured by a plurality of the light-receiving devices 12 disposed at different positions, or images can be captured by light-receiving pixels of different regions in the one light-receiving device 12, so that it is possible to obtain a plurality of images which are not necessarily the same while the optical axes are directed toward the same direction. By matching image data at each of the positions of a plurality of images which are not the same, it is possible to obtain a high-resolution image. For this reason, it is preferable that the planar shapes of the lenses 21 in the one camera module 1D are the same among the four optical units 13 as illustrated in
As illustrated in
The camera module 1E is a monoscopic camera module where an optical unit 13 having one optical axis is provided to one camera module 1E.
As illustrated in
Next, detailed configuration of the camera module 1D according to the fourth embodiment illustrated in
The camera module 1D is configured to include a stacked lens structure 11 where a plurality of the lens-attached substrates 41a to 41e are stacked and the light-receiving device 12. The stacked lens structure 11 includes a plurality of the optical units 13. The one-dotted dash lines 84 indicate the optical axes of the optical units 13. The light-receiving device 12 is disposed under the stacked lens structure 11. In the camera module 1D, light incident from the upper side into the camera module 1D transmits the stacked lens structure 11 and is received by the light-receiving device 12 disposed under the stacked lens structure 11.
The stacked lens structure 11 includes the five stacked lens-attached substrates 41a to 41e. If not particularly distinguished from each other, the five lens-attached substrates 41a to 41e is simply indicated as the lens-attached substrate 41 in the description.
The cross-section shape of the through-hole 83 of each of the lens-attached substrates 41 constituting the stacked lens structure 11 is the so-called tapered-down shape where the opening width is decreased toward the lower side (the side where the light-receiving device 12 is disposed).
The aperture stop plate 51 is disposed on the stacked lens structure 11. The aperture stop plate 51 is configured to include a layer formed with, for example, a material having light absorbing property or light-shielding property. The aperture portion 52 is installed in the aperture stop plate 51.
The light-receiving device 12 is configured with, for example, a front-side illumination type or back-side illumination type CMOS (Complementary Metal Oxide Semiconductor) image sensor. An on-chip lens 71 is formed on the upper surface of the light-receiving device 12 which is closer to the stacked lens structure 11, and external terminals 72 of inputting and outputting signals are formed on the lower surface of the light-receiving device 12.
The stacked lens structure 11, the light-receiving device 12, the aperture stop plate 51, and the like are accommodated in a lens barrel 74.
A structural material 73 is disposed on the upper side of the light-receiving device 12. The stacked lens structure 11 and the light-receiving device 12 are fixed to each other through the structural material 73. The structural material 73 is, for example, an epoxy-based resin.
In the embodiment, although the stacked lens structure 11 is configured to include the five stacked lens-attached substrates 41a to 41e, the number of stacked lens-attached substrates 41 is not particularly limited if the number is two or more.
Each lens-attached substrate 41 constituting the stacked lens structure 11 is configured so that a lens resin portion 82 is added to a carrier substrate 81. The carrier substrate 81 has a through-hole 83, and the lens resin portion 82 is formed inside the through-hole 83. The lens resin portion 82 includes the above-described lenses 21 and represents the portion extending to the carrier substrate 81 to support the lenses 21 and the portion integrated with the material constituting the lenses 21.
In addition, in case of distinguishing the carrier substrates 81, the lens resin portions 82, or the through-holes 83 of the lens-attached substrates 41a to 41e, as illustrated in
<Detailed Description of Lens Resin Portion>
Next, a shape of the lens resin portion 82 will be described by exemplifying the lens resin portion 82a of the lens-attached substrate 41a.
The cross-sectional diagrams of the carrier substrate 81a and the lens resin portion 82a illustrated in
The lens resin portion 82a is a portion formed to be integrated with the material constituting the lens 21 and includes a lens portion 91 and a carrying portion 92. In the above description, the lens 21 corresponds to the lens portion 91 or the entire lens resin portion 82a.
The lens portion 91 is a portion having performance as a lens, in other words, a “portion of refracting light to converge or diverge” or a “portion having a curved surface such as a convex plane, a concave plane, or an aspherical plane or a portion formed by consecutively arranging a plurality of polygons used as lenses using a Fresnel screen or a diffraction grating”.
The carrying portion 92 is a portion extending from the lens portion 91 to the carrier substrate 81a to support the lens portion 91. The carrying portion 92 is configured with an arm portion 101 and a leg portion 102 and is located in an outer circumference of the lens portion 91.
The arm portion 101 is disposed at the outer side of the lens portion 91 to be in contact with the lens portion 91 and extends from the lens portion 91 toward the outside with a certain thickness. The leg portion 102 is a portion of the carrying portion 92 other than the arm portion 101 and is a portion including the portion being in contact with the sidewall of the through-hole 83a. It is preferable that the leg portion 102 is thicker than the arm portion 101 in terms of the thickness of the resin.
The planar shape of the through-hole 83a formed in the carrier substrate 81a is a circle, and the cross-section shape is naturally the same irrespective of the direction of the diameter. The shape of the lens resin portion 82a which is a shape defined according to the forms of the upper and lower mold frames in the lens formation period is also formed so that the cross-section shape is the same irrespective of the direction of the diameter.
In the camera module 1D, the light incident to the module is constricted by the aperture stop plate 51 and, after that, is spread in the inner portion of the stacked lens structure 11 to be incident on the light-receiving device 12 (not shown in
If the thickness of the lens resin portion 82 of the lens-attached substrate 41 is set to be constant, the large-sized lens is more difficult to manufacture than the small-sized lens. This is because the lens is easily deformed by the weight added to the lens in the lens manufacturing period and the large-sized lens is hard to maintain the strength. For this reason, it is preferable that the large-sized lens is formed to be thicker than the small-sized lens. For this reason, in the stacked lens structure 11 of
In order to increase the degree of lens design, the stacked lens structure 11 of
In general, incident light which is incident on a camera module includes vertical incident light and oblique incident light. A large amount of the oblique incident light collides with the aperture stop plate 51 to be absorbed by the aperture stop plate or to be reflected toward the outside of the camera module 1D. The oblique incident light which is not constricted by the aperture stop plate 51 is likely to collide with the sidewall of the through-hole 83 according to the incident angle to be reflected therefrom.
The direction of propagation of the reflected light of the oblique incident light is defined by the incident angle of the oblique incident light 85 and the angle to the sidewall of the through-hole 83 illustrated in
However, in the stacked lens structure 11 illustrated in
In the through-hole 83 of the lens-attached substrate 41, in order to reduce the light colliding on the sidewall and being reflected, it is more preferable that a material having light absorbing property is disposed on the sidewall.
As an example, in case of using the camera module 1D as a camera, when light (for example, visible light) which is desired to be received is set as first light and light (for example, UV light) of which wavelength is different from that of the first light is set as second light, a material obtained by dispersing carbon particles as a first-light (visible light) absorbing material in the resin which is to be cured by the second light (UV light) is applied or sprayed on the surface of the carrier substrate 81, only the resin on the sidewall portion of the through-hole 83 is cured by irradiating with the second light (UV light), and a resin of the other areas is removed, so that a layer of a material having a light absorbing property with respect to the first light (visible light) may be formed on the sidewall of the through-hole 83.
The stacked lens structure 11 illustrated in
Furthermore, as another example, the flat-shaped aperture stop plate 51 is not provided separately from the lens-attached substrate 41, but a layer of a material having a light absorbing property may be formed on the surface of the lens-attached substrate 41, and the layer of the material may be allowed to function as an aperture stop. For example, the material obtained by dispersing carbon particles as a first-light (visible light) absorbing material in the resin which is to be cured by the second light (UV light) is applied or sprayed on the surface of the lens-attached substrate 41, a resin of other areas excluding the area which is desired to transmit light at the time of functioning as an aperture stop is irradiated with the second light (UV light) to cure the resin to remain, the resin of the area which is not cured, that is, the resin of the area where is desired to transmit light at the time of functioning as an aperture stop is removed, so that the aperture stop may be formed in the surface of the lens-attached substrate 41.
In addition, the lens-attached substrate 41 where the aperture stop is to be formed in the surface may be the lens-attached substrate 41 disposed in the uppermost layer of the stacked lens structure 11 or may be the lens-attached substrate 41 in the middle layer of the stacked lens structure 11.
The stacked lens structure 11 illustrated in
As another embodiment, the stacked lens structure 11 may also be a structure including a plurality of the lens-attached substrates 41 and at least one carrier substrate 81 which is not provided with the lens resin portion 82. In this structure, the carrier substrate 81 which is not provided with the lens resin portion 82 may be disposed on the lowermost layer or the uppermost layer of the stacked lens structure 11 or may be disposed as a layer of the inner side of the stacked lens structure 11. Due to the structure, it is possible to obtain a function or an effect that for example, distances among a plurality of the lenses provided to the stacked lens structure 11 or a distance between the lens resin portion 82 of the lowermost layer of the stacked lens structure 11 and the light-receiving device 12 disposed at the lower side of the stacked lens structure 11 are arbitrarily set.
In addition, due to the structure, it is possible to obtain a function or an effect that the opening width of the carrier substrate 81 which is not provided with the lens resin portion 82 is appropriately set, and the material having light absorbing property is disposed in the area excluding the aperture portion, so that the structure is allowed to function as an aperture stop plate.
In
Similarly to the camera module 1D illustrated in
The camera module 1F of
Since the stacked lens structure 11 of the camera module 1F has the structure where the incident light propagates to spread in a fan shape from the aperture portion 52 of the aperture stop plate 51 toward the lower side, in the fan shape where the opening width of the through-hole 83 is increased toward the lower side, for example, the carrier substrate 81 is less likely to interfere with the optical path than a tapered-down shape where the opening width of the through-hole 83 is decreased toward the lower side. Therefore, a function that a degree of lens design is high is obtained.
In addition, with respect to the cross section area of the lens resin portion 82 including the carrying portion 92 in the substrate planar directions, in case of the tapered-down shape where the opening width of the through-hole 83 is decreased toward the lower side, the cross section area in the lower surface of the lens resin portion 82 has a specific size in order to transmit the light beam incident on the lens 21, and the cross section area is increased from the lower surface of the lens resin portion 82 toward the upper surface thereof.
On the contrary, in case of the fan shape where the opening width of the through-hole 83 is increased toward the lower side, the cross section area in the lower surface of the lens resin portion 82 is substantially the same as that of the case of the tapered-down shape, but the cross section area is decreased from the lower surface of the lens resin portion 82 toward the upper surface thereof.
Therefore, due to the structure where the opening width of the through-hole 83 is increased toward the lower side, it is possible to obtain a function or an effect that it is possible to suppress the size of the lens resin portion 82 including the carrying portion 92 to be small. In addition, therefore, due to the structure, it is possible to obtain a function or an effect that it is possible to reduce the difficulty in lens formation occurring in the case where the above-described lenses are large.
In
The camera module 1G of
The stacked lens structure 11 of the camera module 1G is configured to include a lens-attached substrate 41 where the shape of the through-hole 83 is a so-called tapered-down shape where the opening width is decreased toward the lower side (the side where the light-receiving device 12 is disposed) and a lens-attached substrate 41 where the shape of the through-hole 83 is a so-called fan shape where the opening width is increased toward the lower side.
In the lens-attached substrate 41 where the through-hole 83 has a so-called tapered-down shape where the opening width is decreased toward the lower side, as described above, the oblique incident light 85 colliding on the sidewall of the through-hole 83 is reflected in the upward direction, so-called the incident side direction, so that it is possible to obtain a function or an effect that the occurrence of stray light or noise light is suppressed.
Therefore, in the stacked lens structure 11 of
In the lens-attached substrate 41 where the through-hole 83 is formed in a so-called fan shape where the opening width is increased toward the lower side, as described above, the carrier substrate 81 provided to the lens-attached substrate 41 is less likely to interfere with the optical path, so that it is possible to obtain a function or an effect that a degree of lens design is increased and the size of the lens resin portion 82 including the carrying portion 92 provided to the lens-attached substrate 41 is suppressed to be small.
In the stacked lens structure 11 of
Therefore, in the stacked lens structure 11 of
Next, the detailed configuration of the lens-attached substrate 41 will be described.
In addition, in
As the configuration of the lens-attached substrate 41, any one of the configurations of
In the lens-attached substrate 41 illustrated in
In order to prevent ghost or flare caused by light reflection, a film 121 having light absorbing property or light-shielding property is formed on the sidewall of the through-hole 83 of the lens-attached substrate 41. For the convenience, the film 121 is called a light-shielding film 121.
An upper surface layer 122 including an oxide, a nitride, or other insulating materials is formed on the upper surface of the carrier substrate 81 and the lens resin portion 82, and a lower surface layer 123 including an oxide, a nitride, or other insulating materials is formed on the lower surface of the carrier substrate 81 and the lens resin portion 82.
As an example, the upper surface layer 122 is configured with an anti-reflection film obtained by alternately stacking a plurality of low refractive films and a plurality of high refractive films. The anti-reflection film may be configured, for example, by alternately stacking the low refractive films and the high refractive films as a total of four films. The low refractive film is configured with, for example, an oxide film of SiOx (1≤x≤2), SiOC, SiOF, or the like, and the high refractive film is configured with, for example, a metal oxide film of TiO, TaO, Nb2O5, or the like.
In addition, the configuration of the upper surface layer 122 may be designed, for example, so as to obtain desired anti-reflection performance using optical simulation, and material, thickness, the number of stacked films, and the like of the low refractive film and the high refractive film are not particularly limited. In the embodiment, the outermost surface of the upper surface layer 122 is configured with the low refractive film, and the thickness thereof is, for example, in a range of 20 to 1000 nm, the density thereof is, for example, in a range of 2.2 to 2.5 g/cm3, the flatness thereof is, for example, about 1 nm or less of root mean square of roughness Rq (RMS). In addition, as described later in detail, the upper surface layer 122 is a joining film in the joining to other lens-attached substrate 41.
As an example, the upper surface layer 122 may be configured with an anti-reflection film obtained by alternately stacking a plurality of low refractive films and a plurality of high refractive films and may be preferably an inorganic anti-reflection film among the anti-reflection films. As another example, the upper surface layer 122 may be a single-layered film including an oxide, a nitride, or other insulating materials or may be an inorganic film among the single-layered films.
As an example, the lower surface layer 123 may also be configured with an anti-reflection film obtained by alternately stacking a plurality of low refractive films and a plurality of high refractive films and may be preferably an inorganic anti-reflection film among the anti-reflection films. As another example, the lower surface layer 123 may be a single-layered film including an oxide, a nitride, or other insulating materials or may be an inorganic film among the single-layered films.
With respect to the lens-attached substrates 41 of
In the lens-attached substrate 41 illustrated in
In the lens-attached substrate 41 of
This structure may be formed, for example, by a method of forming the lower surface layer 124 on the lower surface of the carrier substrate 81 before forming the lens resin portion 82, and after that, forming the lens resin portion 82. Alternatively, after the lens resin portion 82 is formed, a mask is formed on the lens resin portion 82, a film constituting the lower surface layer 124 is deposited on the lower surface of the carrier substrate 81, for example, by PVD in the state that no mask is formed on the carrier substrate 81.
In the lens-attached substrate 41 of
Similarly, in the lower surface of the lens-attached substrate 41, a lower surface layer 124 including an oxide, a nitride, or other insulating materials is formed on the lower surface of the carrier substrate 81, and the lower surface layer 124 is not formed on the lower surface of the lens resin portion 82.
This structure may be formed, for example, by a method of forming the upper surface layer 125 and the lower surface layer 124 on the carrier substrate 81 before forming the lens resin portion 82, and after that, forming the lens resin portion 82. Alternatively, after the lens resin portion 82 is formed, a mask is formed on the lens resin portion 82, a film constituting the upper surface layer 125 and a film constituting the lower surface layer 124 are deposited on the surfaces of the carrier substrate 81, for example, by PVD in the state that no mask is formed on the carrier substrate 81. The lower surface layer 124 and the upper surface layer 125 may be configured with the same material or may be configured with different materials.
The lens-attached substrate 41 may be configured as described heretofore.
Next, a manufacturing method for the lens-attached substrate 41 will be described with reference to
First, a substrate-state carrier substrate 81W where a plurality of the through-holes 83 are formed is prepared. As the carrier substrate 81W, for example, a silicon substrate used for a typical semiconductor device may be used. The shape of the carrier substrate 81W is, for example, a circle as illustrated in
In addition, in the embodiment, the planar shape of the through-hole 83 is a circle as illustrated in
The opening width of the through-hole 83 may be taken in a range of, for example, from about 100 μm to about 20 mm. In this case, in the carrier substrate 81W, for example, about one hundred to five million through-holes may be disposed.
In this specification, the size of the through-hole 83 in the planar directions of the lens-attached substrate 41 is called the opening width. With respect to the opening width, if there no particularly specification, in the case where the planar shape of the through-hole 83 is a quadrangle, the opening width denotes a length of one side, and in the case where the planar shape of the through-hole 83 is a circle, the opening width denotes a diameter.
As illustrated in
As an example of a three-dimensional shape of the through-hole 83 where the second opening width 132 is smaller than the first opening width 131, the through-hole 83 may have a truncated conical shape illustrated in
With respect to the through-hole 83 where the second opening width 132 is smaller than the first opening width 131, a resin is supplied into the through-hole 83, when the lens resin portion 82 is formed by pressing the resin with mold frame members in the facing directions from the first and second surfaces, the resin which is to be the lens resin portion 82 is pressed on the sidewall of the through-hole 83 by being exerted on by forces from the two facing mold frame members. Therefore, a function can be obtained that the adhesion strength between the resin which is to be the lens resin portion 82 and the carrier substrate is increased.
In addition, as another embodiment of the through-hole 83, the first opening width 131 and the second opening width 132 may have the same shape, and in other words, may have the shape where the cross-section shape of the sidewall of the through-hole 83 is vertical.
<Method of Forming Through-Hole Using Wet Etching>
The through-hole 83 of the carrier substrate 81W can be formed by etching the carrier substrate 81W by wet etching. More specifically, before the etching of the carrier substrate 81W is performed, an etching mask for preventing non-opening regions of the carrier substrate 81W from being etched is formed on the surface of the carrier substrate 81W. As a material of the etching mask, for example, an insulating film such as a silicon oxide film or a silicon nitride film is used. The etching mask is formed by forming a layer of an etching mask material on the surface of the carrier substrate 81W and opening a pattern which is to be the planar shape of the through-hole 83 on the layer. After the etching mask is formed, the through-hole 83 is formed on the carrier substrate 81W by etching the carrier substrate 81W.
As the carrier substrate 81W, for example, in case of using monocrystalline silicon of which the substrate surface orientation is (100), in order to form the through-hole 83, crystal anisotropic wet etching using an alkaline solution such as KOH can be employed.
If the crystal anisotropic wet etching using an alkaline solution such as KOH performed on the carrier substrate 81W which is a monocrystalline silicon of which the substrate surface orientation is (100), the etching is performed so that the (111) plane appears on opening sidewall. As a result, in the case where the planar shape of the opening portion of the etching mask is any one of a circle and a quadrangle, the through-hole 83 is obtained so that the planar shape thereof is a quadrangle; with respect to the opening width of the through-hole 83, the second opening width 132 is smaller than the first opening width 131; and the three-dimensional shape of the through-hole 83 is a truncated pyramidal shape or a shape similar to the truncated pyramidal shape. The angle of the sidewall of the through-hole 83 which becomes the truncated pyramidal shape is about 55° with respect to the substrate plane.
As another example of the etching for forming the through-hole, wet etching using a chemical solution capable of etching silicon in an arbitrary shape without restriction to crystal orientation disclosed in WO 2011/010739 or the like may be performed. As the chemical solution, for example, a chemical solution obtained by adding at least one of polyoxyethylene alkyl phenyl ether, polyoxyalkylene alkyl ether, and polyethylene glycol to a TMAH (tetra-methyl ammonium hydroxide) aqueous solution, a chemical solution obtained by adding isopropyl alcohol to a KOH solution, or the like may be employed.
If the etching for forming the through-hole 83 is performed on the carrier substrate 81W which is a monocrystalline silicon of which the substrate surface orientation is (100) by using any one of the above-described chemical solutions, in the case where planar shape of the opening portion of the etching mask is a circle, the through-hole 83 is obtained so that the planar shape is a circle; the second opening width 132 is smaller than the first opening width 131; and the three-dimensional shape is a truncated cone or a shape similar to the truncated cone.
In the case where the planar shape of the opening portion of the etching mask is a quadrangle, the through-hole 83 is obtained so that the planar shape is a quadrangle; with respect to the opening width, the second opening width 132 is smaller than the first opening width 131; and the three-dimensional shape is a truncated pyramidal shape or a shape similar to the truncated pyramidal shape. The angle of the sidewall of the through-hole 83 which becomes the truncated cone or the truncated pyramidal shape is about 45° with respect to the substrate plane.
<Method of Forming Through-Hole Using Dry Etching>
In addition, in the etching for forming the through-hole 83, not the above-described wet etching but dry etching may be used.
The method of forming the through-hole 83 using the dry etching will be described with reference to
As illustrated in
Next, as illustrated in
Next, the protective film formation process, the dry etching process, and the etching mask recession process of
Finally, if the etching mask 141 is removed, as illustrated in
As described heretofore, in case of forming the through-hole 83 using the dry etching, the protective film formation process, the dry etching process, and the etching mask recession process are repeatedly performed.
Since the sidewall of the through-hole 83 has the periodic staircase shape (concave-convex shape), it is possible to suppress reflection of the incident light. In addition, in the case where the sidewall of the through-hole 83 has a concave-convex shape having a random size, voids are generated in the adhesion layer between the lens formed in the through-hole 83 and the sidewall, in some cases, the adhesiveness to the lens may be deteriorated due to the voids. However, according to the above-described forming method, since the sidewall of the through-hole 83 has the periodic concave-convex shape, the adhesiveness is improved, so that it is possible to suppress a change in optical characteristic according to a difference in lens position.
As examples of the materials used in the processes, for example, the carrier substrate 81W may be monocrystalline silicon, the etching mask 141 may be photoresist, the protective film 142 may be a fluorocarbon polymer formed by using gas plasma such as C4F8 or CHF3, the etching process may be plasma etching using a gas containing F such as SF6/O2 or C4F8/SF6, the mask recession process may be plasma etching including O2 such as an O2 gas or CF4/O2.
In addition, the carrier substrate 81W may be a monocrystalline silicon, the etching mask 141 may be SiO2, the etching may be plasma containing Cl2, the protective film 142 may be an oxide film obtained by oxidizing an etching target material by using O2 plasma, the etching process may plasma etching using a gas containing Cl2, and the mask recession process may be plasma etching using a gas containing F such as CF4/O2.
As described heretofore, although a plurality of the through-holes 83 are simultaneously formed in the carrier substrate 81W by wet etching or dry etching, as illustrated in
For example, as illustrated in
In addition, the through-grooves 151 of the carrier substrate 81W may be disposed at the same positions among the lens-attached substrates 41 constituting the stacked lens structure 11. In this case, as illustrated in the cross-sectional diagram of
Due to the through-groove 151 of the carrier substrate 81W as a portion of the lens-attached substrate 41, it is possible to obtain a function or an effect that, for example, in the case where a stress of deforming the lens-attached substrate 41 is exerted from an outer portion of the lens-attached substrate 41, the deformation of the lens-attached substrate 41 caused by the stress is alleviated.
In addition, due to the through-groove 151, it is possible to obtain a function or an effect that, for example, in the case where the stress of deforming the lens-attached substrate 41 is generated from an inner portion of the lens-attached substrate 41, the deformation of the lens-attached substrate 41 caused by the stress is alleviated.
<Manufacturing Method for Lens-Attached Substrate>
Next, a manufacturing method for the substrate-state lens-attached substrate 41W will be described with reference to
First, as illustrated in
A front-side flat portion 171 at the upper side of the carrier substrate 81W and a rear-side flat portion 172 at the lower side of the carrier substrate are flat planes which are formed to be so flat that plasma joining can be performed in the subsequent process. The thickness of the carrier substrate 81W functions as a spacer of determining a lens distance when the substrate is finally diced into lens-attached substrates 41 and the lens-attached substrate is superimposed on other lens-attached substrates 41.
It is preferable that a low-thermal-expansion coefficient substrate material of which the thermal expansion coefficient is 10 ppm/° C. or less is used for the carrier substrate 81W.
Next, as illustrated in
Next, as illustrated in
Next, as illustrated in
With respect to the height direction which is the vertical direction in the figure, the position of the upper mold frame 201 is fixed by a control device of controlling the distance between the upper mold frame 201 and the lower mold frame 181 so that the distance between the upper mold frame 201 and the lower mold frame 181 is a preset distance. At this time, the space interposed between the optical transfer surface 202 of the upper mold frame 201 and the optical transfer surface 182 of the lower mold frame 181 has a thickness equal to the thickness of the lens resin portion 82 (lens 21) calculated according to optical design.
In addition, as illustrated in
When the interval between the upper mold frame 201 and lower mold frame 181 is controlled so as to be a preset distance, in the above-described process of
Subsequently, in the state illustrated in
Instead of the energy curable resin 191, a thermoplastic resin may be used. In this case, in the state illustrated in
Next, as illustrated in
In addition, the surfaces of the upper mold frame 201 and the lower mold frame 181 being in contact with the carrier substrate 81W may be coated with a fluorine-based or silicon-based mold-releasing agent, or the like. By doing so, it is possible to easily demold the upper mold frame 201 and the lower mold frame 181 from the carrier substrate 81W. In addition, as a method of easily demolding from the contact surface of the carrier substrate 81W, various types of coating such as fluorine containing DLC (diamond like carbon) may be performed.
Next, as illustrated in
By compression-molding (imprinting) the energy curable resin 191 in the through-hole 83 formed in the carrier substrate 81W by using the upper mold frame 201 and the lower mold frame 181, the lens resin portion 82 is formed, and thus, the lens-attached substrate 41 can be manufactured.
The shapes of the optical transfer surface 182 and the optical transfer surface 202 are not limited to the above-described concave shape, but the shapes may be appropriately determined according to the shape of the lens resin portion 82. As illustrated in
In addition, the shape of the optical transfer surface 182 and the shape of the optical transfer surface 202 may be a shape where the lens shape after the formation becomes a moth-eye structure.
According to the above-described manufacturing method, since a change in distance between the lens resin portions 82 in the planar directions caused by the curing-contraction of the energy curable resin 191 can be prevented by using the carrier substrate 81W, it is possible to control the lens distance at a high accuracy. In addition, it is possible to obtain an effect that the energy curable resin 191 having weak strength is reinforced by the carrier substrate 81W having strong strength. Therefore, it is possible to obtain effects that it is possible to provide a lens array substrate where a plurality of the lenses having a good handling property are disposed and it is possible to suppress a bent state of the lens array substrate.
<Example of Polygon of Through-Hole Shape>
As illustrated in
The cross-sectional diagrams of the lens-attached substrate 41a of
As understood by comparing the cross-sectional diagram of B-B′ line and the cross-sectional diagram of C-C′ line, in the case where the through-hole 83a is a quadrangle, the distance from the center of the through-hole 83a to the upper outer edge of the through-hole 83a and the distance from the center of the through-hole 83a to the lower outer edge of the through-hole 83a are different in the side direction and the diagonal direction of the through-hole 83a which is a quadrangle, and the distances are large in the diagonal direction. For this reason, in the case where the planar shape of the through-hole 83a is a quadrangle, if the lens portion 91 is set to be a circle, there is a need that the distance from the outer circumference of the lens portion 91 to the sidewall of the through-hole 83a sidewall, in other words, the length of the carrying portion 92 is set to be different between the side direction and the diagonal direction of the quadrangle.
Therefore, the lens resin portion 82a illustrated in
As illustrated in
In the lens resin portion 82a of
In addition, since the entire lens portion 91 is supported evenly by a constant force, for example, in the case where a stress is applied to the entire outer circumference of the through-hole 83a by the carrier substrate 81a surrounding the through-hole 83a, the stress is exerted on the entire lens portion 91 evenly, so that it is possible to obtain a function or an effect that unevenly transferring of the stress to a specific portion of the lens portion 91 is suppressed.
The cross-sectional diagrams of the lens-attached substrate 41a of
In
Therefore, the lens resin portion 82a illustrated in
As illustrated in
In the embodiment of
The lens resin portion 82 and the through-hole 83 illustrated in
A method of forming the step-shaped through-hole 83 illustrated in
First, as illustrated in
Next, a hard mask 242 having resistance to the wet etching at the time of opening the through-hole is formed on the other surface of the carrier substrate 81W. The hard mask 242 may also be made of, for example, a silicon nitride film.
Next, as illustrated in
Next, as illustrated in
Next, as illustrated in
Next, as illustrated in
Finally, as illustrated in
As described heretofore, the etching of the carrier substrate 81W for forming the through-hole by wet etching is performed as two times of divided etchings, so that the step-shaped through-hole 83 illustrated in
The cross-sectional diagrams of the lens-attached substrate 41a of
In the case where the planar shape of the through-hole 83a is a circle, the cross-section shape of the through-hole 83a is naturally the same irrespective of the direction of the diameter. In addition, the cross-section shapes of the outer edge of the lens resin portion 82a, the arm portion 101, and the leg portion 102 are formed as to be the same irrespective of the direction of the diameter.
In comparison with the through-hole 83a of
The cross-sectional diagrams of the lens-attached substrate 41a of
The lens resin portion 82 and the through-hole 83 illustrated in
As illustrated in
In the lens resin portion 82a of
In addition, since the entire lens portion 91 is supported evenly by a constant force, for example, in the case where a stress is applied to the entire outer circumference of the through-hole 83a by the carrier substrate 81a surrounding the through-hole 83a, the stress is exerted on the entire lens portion 91 evenly, so that it is possible to obtain a function or an effect that unevenly transferring of the stress to a specific portion of the lens portion 91 is suppressed.
In addition, in comparison with the through-hole 83a of
Next, direct joining of the substrate-state lens-attached substrates 41W where a plurality of the lens-attached substrates 41 are formed will be described.
In the description hereinafter, as illustrated in
Direct joining of the substrate-state lens-attached substrate 41W-a and the substrate-state lens-attached substrate 41W-b will be described with reference to
In addition, in
An upper surface layer 122 or 125 is formed on the upper surfaces of the lens-attached substrate 41W-a and the lens-attached substrate 41W-b. A lower surface layer 123 or 124 is formed on the lower surfaces of the lens-attached substrate 41W-a and the lens-attached substrate 41W-b. Next, as illustrated in
Next, as illustrated in
By the process of adhering the lens-attached substrates, hydrogen bonding occurs between hydrogen of OH group of the surface of the lower surface layer 123 or 124 of the lens-attached substrate 41W-a and hydrogen of OH group of the surface of the upper surface layer 122 or 125 of the lens-attached substrate 41W-b. Therefore, the lens-attached substrate 41W-a and the lens-attached substrate 41W-b are fixed to each other. The process of adhering the lens-attached substrates can be performed under the condition of atmospheric pressure.
An annealing process is applied to the lens-attached substrate 41W-a and the lens-attached substrate 41W-b which are subject to the above-described adhering process. Therefore, dehydration condensation occurs from the state that the OH groups are hydrogen-bonded, a covalent bond through oxygen is formed between the lower surface layer 123 or 124 of the lens-attached substrate 41W-a and the upper surface layer 122 or 125 of the lens-attached substrate 41W-b. Alternatively, elements included in the lower surface layer 123 or 124 of the lens-attached substrate 41W-a and elements included in the upper surface layer 122 or 125 of the lens-attached substrate 41W-b are covalent-bonded. By this bonding, the two lens-attached substrates are firmly fixed to each other. In this manner, the covalent bond is formed between the lower surface layer 123 or 124 of the lens-attached substrate 41W disposed at the upper side and the upper surface layer 122 or 125 of the lens-attached substrate 41W disposed at the lower side, and thus, the two lens-attached substrates 41W are fixed to each other, which is called “direct joining” in this specification. The method of fixing a plurality of the lens-attached substrates over the entire substrate surface by using a resin disclosed in PTL 1 has a problem of the curing contraction or thermal expansion of the resin and the deformation of lens caused by the curing contraction or thermal expansion of the resin. On the contrary, in the direct joining according to an embodiment of the present technology, since any resin is not used at the time of fixing a plurality of the lens-attached substrates 41W, it is possible to obtain a function or an effect that, without occurrence of the curing-contraction or the thermal expansion, it is possible to fix a plurality of the lens-attached substrates 41W.
The annealing process may also be performed under the condition of atmospheric pressure. In order to perform the dehydration condensation, the temperature of the annealing process may be set to be 100° C. or more, 150° C. or more, or 200° C. On the other hand, in terms of protecting the energy curable resin 191 for forming the lens resin portion 82 from heat or suppressing degassing from the energy curable resin 191, the temperature of the annealing process may be set to be 400° C. or less, 350° C. or less, or 300° C. or less.
If the process of adhering the lens-attached substrates 41W or the process of directly joining the lens-attached substrates 41W is performed under the condition other than the atmospheric pressure, when the joined lens-attached substrate 41W-a and lens-attached substrate 41W-b are returned to the environment of atmospheric pressure, there occurs a difference in pressure between the space between the joined lens resin portion 82 and the lens resin portion 82 and the outside of the lens resin portion 82. Due to the difference in pressure, pressure is exerted on the lens resin portion 82, there is a problem in that the lens resin portion 82 is deformed.
Due to the performing of the process of adhering the lens-attached substrates 41W and the process of directly joining the lens-attached substrates under the condition of atmospheric pressure, it is possible to obtain a function or an effect that the deformation of the lens resin portion 82 which may occur in case of performing the joining under the condition other than the atmospheric pressure can be avoided.
Since the direct joining of the substrate by performing the plasma activation process, in other words, the plasma joining can suppress fluid flowing and thermal expansion, for example, in case of using a resin as the adhesive, it is possible to improve position accuracy at the time of joining the lens-attached substrate 41W-a and the lens-attached substrate 41W-b.
As described above, the upper surface layer 122 or the lower surface layer 123 are formed on the rear-side flat portion 172 of the lens-attached substrate 41W-a and the front-side flat portion 171 of the lens-attached substrate 41W-b. In the upper surface layer 122 and the lower surface layer 123, dangling bonds are easily formed by the previously-performed plasma activation process. Namely, the lower surface layer 123 formed on the rear-side flat portion 172 of the lens-attached substrate 41W-a and the upper surface layer 122 formed on the front-side flat portion 171 of the lens-attached substrate 41W-b have a function of increasing the joining strength.
In addition, in the case where the upper surface layer 122 or the lower surface layer 123 is configured with an oxide film, since the oxide film is not influenced by a change in film quality caused by plasma (O2), it is also possible to obtain an effect that corrosion by plasma for the lens resin portion 82 is suppressed.
As described heretofore, the substrate-state lens-attached substrate 41W-a where a plurality of the lens-attached substrates 41a are formed and the substrate-state lens-attached substrate 41W-b where a plurality of the lens-attached substrates 41b are formed are subject to the surface activation process using plasma and, after that, are directly joined, in other words, are joined by using plasma joining.
First, as illustrated in
Next, as illustrated in
Next, as illustrated in
Next, as illustrated in
Next, as illustrated in
Finally, as illustrated in
In this manner, the five substrate-state lens-attached substrates 41W-a to 41W-e are sequentially stacked one by one from the lower-layer lens-attached substrate 41W to the upper-layer lens-attached substrate 41W in the stacked lens structure 11, so that the substrate-state stacked lens structure 11W is obtained.
First, as illustrated in
Next, as illustrated in
Next, as illustrated in
Next, as illustrated in
Next, as illustrated in
Finally, as illustrated in
In this manner, the five substrate-state lens-attached substrates 41W-a to 41W-e are sequentially stacked one by one from the upper-layer lens-attached substrate 41W to the lower-layer lens-attached substrate 41W in the stacked lens structure 11, so that the substrate-state stacked lens structure 11W is obtained.
The five substrate-state lens-attached substrates 41W-a to 41W-e which are stacked by the stacking method described with reference to
In the description of
In the camera module 1H of
In the camera module 1H of
More specifically, the structural material 301a is disposed at a portion of the upper side of the light-receiving device 12. The light-receiving device 12 and the light-transmitting substrate 302 are fixed to each other through the structural material 301a. The structural material 301a is, for example, an epoxy-based resin.
The structural material 301b is disposed at the upper side of the light-transmitting substrate 302. The light-transmitting substrate 302 and the stacked lens structure 11 are fixed to each other through the structural material 301b. The structural material 301b is, for example, an epoxy-based resin.
On the contrary, in the camera module 1J of
The resin layer 311 is disposed on the entire upper-side surface of the light-receiving device 12. The light-receiving device 12 and the light-transmitting substrate 302 are fixed to each other through the resin layer 311. Due to the resin layer 311 disposed on the entire upper-side surface of the light-receiving device 12, it is possible to obtain a function or an effect that, in the case where stress is applied from the upper side of the light-transmitting substrate 302 to the light-transmitting substrate 302, the stress is prevented from being concentrated on some portion of the light-receiving device 12 and, and thus, the stress is distributively received by the entire surface of the light-receiving device 12.
A structural material 301b is disposed at the upper side of the light-transmitting substrate 302. The light-transmitting substrate 302 and the stacked lens structure 11 are fixed through the structural material 301b.
The camera module 1H of
In a camera module 1J illustrated in
The lens barrel 74, the shaft 331, the moving member 332, and the fixing member 333 are accommodated in a housing 334. A protective substrate 335 is disposed in the upper portion of the light-receiving device 12, and the protective substrate 335 and the housing 334 are connected to each other by an adhesive 336.
Due to the above-described mechanism of moving the stacked lens structure 11, it is possible to obtain a function or an effect that, when a camera using the camera module 1J captures an image, autofocus operation can be allowed to be performed.
A camera module 1L of
Namely, in the camera module 1L, similarly to the camera module 1H of
A piezoelectric device 351 is disposed at the upper side of the light-transmitting substrate 302. The light-transmitting substrate 302 and the stacked lens structure 11 are fixed to each other through the piezoelectric device 351.
In the camera module 1L, by applying a voltage to the piezoelectric device 351 disposed at the lower side of the stacked lens structure 11 or by cutting off the voltage, the stacked lens structure 11 can be moved in the upward and downward directions. The means for moving the stacked lens structure 11 is not limited to the piezoelectric device 351, but other devices of which shape is changed according to applying or cutting-off of the voltage may be used. For example, a MEMS device may be used.
Due to the above-described mechanism of moving the stacked lens structure 11, it is possible to obtain a function or an effect that, when a camera using the camera module 1L captures an image, autofocus operation can be allowed to be performed.
The stacked lens structure 11 is a structure (hereinafter, referred to as the structure according to an embodiment of the present technology) where the lens-attached substrates 41 are directly joined. The functions and effects of the structure according to an embodiment of the present technology will be described in comparison with other structures of lens-attached substrates where lenses are formed.
A wafer-level stacked structure 1000 illustrated in
In a lens array substrate 1041 illustrated in
A manufacturing method for the lens array substrate 1041 of
The lens array substrate 1041 has the following features. (1) The resin 1054 formed at the positions of the through-holes 1052 of the substrate 1051 becomes the lenses 1053, and a plurality of the lenses 1053 are formed in the substrate 1051. In addition, (2) a thin layer of the resin 1054 is formed on the entire upper surface of the substrate 1051 disposed between a plurality of the lenses 1053.
In case of forming the structure where a plurality of the lens array substrates 1041 are stacked, it is possible to obtain a function or an effect that the thin layer of the resin 1054 formed on the entire upper surface of the substrate 1051 functions as an adhesive of adhering the substrates.
In addition, in case of forming the structure where a plurality of the lens array substrates 1041 are stacked, in comparison with the wafer-level stacked structure 1000 of
<Functions Obtained from Resin in Comparative Structure Example 2>
In Comparative Literature 2 disclosing the lens array substrate 1041 of
In Comparative Structure Example 2, as the resin 1054, an energy curable resin is used. In addition, as an example of the energy curable resin, a photocurable resin is used. In the case where the photocurable resin is used as the energy curable resin, if the resin 1054 is irradiated with UV light, the resin 1054 is cured. By the curing, the resin 1054 is curing-contacted.
However, according to the structure of the lens array substrate 1041 of
In a lens array substrate 1081 illustrated in
A manufacturing method for the lens array substrate 1081 of
The lens array substrate 1081 has the following features. (1) The resin 1094 formed at the positions of the through-holes 1092 of the substrate 1091 becomes the lenses 1093, and a plurality of the lenses 1093 are formed in the substrate 1091. In addition, (2) a thin layer of the resin 1094 is formed on the entire upper surface of the substrate 1091 disposed between a plurality of lenses 1093.
<Functions Obtained from Resin in Comparative Structure Example 3>
In Comparative Literature 3 disclosing the lens array substrate 1081 of
In the Comparative Structure Example 3, as the resin 1094, an energy curable resin is used. In addition, an example of the energy curable resin, a photocurable resin is used. In the case where the photocurable resin is used as the energy curable resin, if the resin 1094 is irradiated with UV light, the resin 1094 is cured. By the curing, the resin 1094 is curing-contracted.
However, according to the structure of the lens array substrate 1081 of
As described heretofore, Comparative Literature 2 and 3 disclose that, when a photocurable resin is cured, curing-contraction occurs. In addition, the fact that, when a photocurable resin is cured, curing-contraction occurs is also disclosed in, for example, JP 2013-1091 A or the like besides Comparative Literature 2 and 3.
In addition, if a resin is molded in a lens shape and the molded resin is cured, there is a problem in that the curing-contraction occurs in the resin. However, this problem is not limited to the photocurable resin. For example, similarly to the photocurable resin, in a thermosetting resin as a kind of an energy curable resin, there is a problem in that the curing-contraction occurs in the curing period. This is disclosed in, for example, Comparative Literature 1 and 3, JP 2010-204631 A, and the like.
The lens array substrate 1121 of
The lens array substrate 1121 has the following features. (1) The resin 1144 formed at the positions of the through-holes 1142 of the substrate 1141 becomes the lenses 1143, and a plurality of the lenses 1143 are formed in the substrate 1141. In addition, (2) a thin layer of the resin 1144 is formed on the entire upper surface of the substrate 1141 disposed between a plurality of lenses 1143, and a thin layer of the resin 1144 is also formed in a portion of the lower surface of the substrate 1141.
<Functions Obtained from Resin in Comparative Structure Example 4>
In Comparative Literature 2 disclosing the lens array substrate 1121 of
In the lens array substrate 1121 of
However, in the lens array substrate 1121 of Comparative Structure Example 4, in a certain area of the lower surface of the substrate 1141 as well as the entire upper surface of the substrate 1141 located between a plurality of lenses 1143, a thin layer of the resin 1144 is formed.
In this manner, in the structure, the resin 1144 is formed on both of the upper surface and the lower surface of the substrate 1141, so that the directions of the bent state of the entire lens array substrate 1121 can be canceled out.
On the contrary, in the lens array substrate 1041 illustrated in
Therefore, in the lens array substrate 1121 of
The lens array substrate 1161 of
In addition,
The lens array substrate 1161 has the following features. (1) The resin 1174 formed at the positions of the through-holes 1172 of the substrate 1171 becomes the lenses 1173, and a plurality of the lenses 1173 are formed in the substrate 1171. In addition, (2) a thin layer of the resin 1174 is formed on the entire upper surface of the substrate 1171 disposed between a plurality of the lenses 1173, and a thin layer of the resin 1174 is also formed in a portion of the lower surface of the substrate 1171.
In Comparative Literature 2 disclosing the lens array substrate 1161 of
In the lens array substrate 1161 of
However, in the lens array substrate 1171 of Comparative Structure Example 5, in a certain area of the lower surface of the substrate 1171 as well as the entire upper surface of the substrate 1171 located between a plurality of the lenses 1173, a thin layer (resin protruding region 1175) of the resin 1174 is formed. Therefore, the directions of the bent state of the entire lens array substrate 1171 are canceled out, so that it is possible to provide a lens array substrate where the amount of the bent state can be allowed to be small.
<Comparison of Functions Obtained from Resin of Comparative Structure Examples 2 to 5>
The functions obtained from the resin of Comparative Structure Examples 2 to 5 are summarized as follows.
(1) Like Comparative Structure Examples 2 and 3, in case of the structure where the layer of resin is disposed on the entire upper surface of the lens array substrate, the bent state occurs in the substrate where a plurality of the lenses are disposed.
As illustrated in
On the other hand, the lens array substrate 1211 itself is neither contracted nor expanded even through the lens array substrate is irradiated with UV light. Namely, in the lens array substrate 1211 itself, no force caused by the substrate is generated. As a result, as illustrated in
(2) However, like Comparative Structure Examples 4 and 5, in case of the structure where the layer of the resin is disposed on both of the upper surface and the lower surface of the lens array substrate, since the directions of the bent state of the lens array substrate are canceled out, the amount of the bent state of the lens array substrate can be allowed to be smaller than that of Comparative Structure Examples 2 and 3.
As illustrated in
On the contrary, the lens array substrate 1211 itself is neither contracted nor expanded even though the lens array substrate is irradiated with UV light. Namely, in the lens array substrate 1211 itself, no force caused by the substrate is generated.
On the other hand, the layer of the photocurable resin 1212 disposed on the lower surface of the lens array substrate 1211 is curing-contracted by UV light irradiation for curing. Therefore, in the layer of the photocurable resin 1212 disposed on the lower surface of the lens array substrate 1211, a force caused by the photocurable resin 1212 is generated in the contraction direction. For this reason, a force of bending the lens array substrate 1211 in an upward convex shape is exerted on the lower surface side of the lens array substrate 1211.
A force of bending the lens array substrate 1211 in a downward convex shape exerted on the upper surface side of the lens array substrate 1211 and a force of bending the lens array substrate 1211 in an upward convex shape exerted on the lower surface side of the lens array substrate 1211 cancel each other out.
As a result, as illustrated in
In this manner, the force of bending the lens array substrate and the amount of the bent state of the lens array substrate are influenced by a relationship between (1) the direction and magnitude of the force exerted on the lens array substrate in the upper surface of the lens array substrate and (2) the direction and magnitude of the force exerted on the lens array substrate in the lower surface of the lens array substrate.
Therefore, for example, as illustrated in
In Comparative Structure Example 6, in the layer of the photocurable resin 1212 disposed on the upper surface of the lens array substrate 1211, a force caused by the photocurable resin 1212 is generated in the contraction direction. In the lens array substrate 1211 itself, no force caused by the substrate is generated. For this reason, a force of bending the lens array substrate 1211 in a downward convex shape is exerted on the upper surface side of the lens array substrate 1211.
On the other hand, in the layer of the photocurable resin 1212 disposed on the lower surface of the lens array substrate 1211, a force caused by the photocurable resin 1212 is generated in the contraction direction. In the lens array substrate 1211 itself, no force caused by the substrate is generated. For this reason, a force of bending the lens array substrate 1211 in an upward convex shape is exerted on the lower surface side of the lens array substrate 1211.
The two forces of bending the lens array substrate 1211 are exerted in the directions to cancel each other out further in comparison with the structure illustrated in
However, actually, all shapes of the lens-attached substrates constituting the stacked lens structure incorporated into the camera module are not the same. More specifically, in some cases, a plurality of the lens-attached substrates constituting the stacked lens structure may be different, for example, in terms of thickness of the lens-attached substrate or size of the through-hole or may be different in terms of thickness, shape, volume, or the like of the lens formed in the through-hole. In addition, in some cases, the lens-attached substrates may be different in terms of thickness or the like of the photocurable resin formed in the upper surface and the lower surface of the lens-attached substrate.
The stacked lens structure 1311 illustrated in
Hereinafter, among the three lens-attached substrates 1321 to 1323, the middle-layered lens-attached substrate 1321 is referred to as a first lens-attached substrate 1321, the uppermost-layer lens-attached substrate 1322 is referred to as a second lens-attached substrate 1322, and the lowermost-layer lens-attached substrate 1323 is referred to as a third lens-attached substrate 1323.
The second lens-attached substrate 1322 disposed in the uppermost layer and the third lens-attached substrate 1323 disposed on the lowermost layer are different from each other in terms of a substrate thickness and a lens thickness.
More specifically, the lens thickness in the third lens-attached substrate 1323 is formed to be larger than that of the second lens-attached substrate 1322, and thus, the substrate thickness in the third lens-attached substrate 1323 is also formed to be larger than that of the second lens-attached substrate 1322.
A resin 1341 is formed over the entire contact surface between the first lens-attached substrate 1321 and the second lens-attached substrate 1322 and over the entire contact surface between the first lens-attached substrate 1321 and the third lens-attached substrate 1323.
The cross-section shape of the through-hole of the three lens-attached substrates 1321 to 1323 is the so-called fan shape where the lower surface of the substrate is larger than the upper surface of the substrate.
A function obtained from the three lens-attached substrates 1321 to 1323 having different shapes will be described with reference to
Like the stacked lens structure 1311, in the case where the second lens-attached substrate 1322 and the third lens-attached substrate 1323 which are different in substrate thickness are disposed on the upper surface and the lower surface of the first lens-attached substrate 1321, the force of bending the stacked lens structure 1311 and the amount of the bent state of the stacked lens structure 1311 are changed according to which positions of the stacked lens structure 1311 in the thickness direction the layers of the resin 1341 existing over the entire surfaces of the contact surfaces among the three lens-attached substrates 1321 to 1323 exist.
If the layers of the resin 1341 existing over the entire surfaces of the contact surfaces among the three lens-attached substrates 1321 to 1323 are not disposed symmetrically with respect to the center line of the stacked lens structure 1311, that is, the line passing through the thickness-direction center of the stacked lens structure 1311 along the substrate planar directions, functions of the forces generated by the curing-contraction of the resin 1341 disposed on the upper surface and the lower surface of the first lens-attached substrate 1321 are not completely canceled out as illustrated in
For example, in the case where the two layers of the resin 1341 on the upper surface and the lower surface of the first lens-attached substrate 1321 are disposed so as to be deviated upwards from the center line of the stacked lens structure 1311 in the thickness direction, if the two layers of resin 1341 are curing-contracted, the stacked lens structure 1311 is bent in a downward convex shape as illustrated in
In addition, in the case where the cross-section shape of the through-hole of the thinner substrate between the second lens-attached substrate 1322 and the third lens-attached substrate 1323 is a shape which is increased toward the direction of the first lens-attached substrate 1321, the problem in that the lens is lost or damaged is increased.
In the example illustrated in
Next, the case where the resin is thermally expanded is considered.
Comparative Structure Example 8 of
When a user actually uses a camera module, due to an increase in power consumption according to the operation, a temperature of the housing of the camera is increased, and thus, a temperature of the camera module is also increased. Due to the increase in temperature, in the stacked lens structure 1311 of
Although the area and thickness of the resin 1341 disposed on the upper surface and the lower surface of the first lens-attached substrate 1321 are set to be the same as illustrated in
For example, in the case where the two layers of the resin 1341 on the upper surface and the lower surface of the first lens-attached substrate 1321 are disposed so as to be deviated upwards from the center line of the stacked lens structure 1311 in the thickness direction, if the two layers of the resin 1341 are thermally expand, the stacked lens structure 1311 is bent in an upward convex shape as illustrated in
In addition, in the example illustrated in
<Structure According to Embodiment of the Present Technology>
The stacked lens structure 1371 is a structure where a second lens-attached substrate 1362 is disposed above a first lens-attached substrate 1361 as the middle lens-attached substrate and a third lens-attached substrate 1363 is disposed under the first lens-attached substrate 1361.
The second lens-attached substrate 1362 disposed in the uppermost layer and the third lens-attached substrate 1363 disposed in the lowermost layer are different from each other in terms of a substrate thickness and a lens thickness. More specifically, the lens thickness in the third lens-attached substrate 1363 is formed to be larger than that of the second lens-attached substrate 1362, and thus, the substrate thickness in the third lens-attached substrate 1363 is also formed to be larger than that of the second lens-attached substrate 1362.
In the stacked lens structure 1371 of the structure according to an embodiment of the present technology, as a means for fixing the lens-attached substrates, direct joining of the substrates is used. In other words, a plasma activation process is performed on the to-be-fixed lens-attached substrates, so that the two to-be-fixed lens-attached substrates are plasma-joined. Furthermore, in other words, silicon oxide films are formed on the surfaces of the to-be-stacked two lens-attached substrates, hydroxyl groups are bonded thereto, after that, the two lens-attached substrates are adhered to each other, and de-hydration condensation is performed by increasing the temperature of the substrates. By doing so, the two lens-attached substrates are directly joined by silicon-oxygen covalent bonds.
Therefore, in the stacked lens structure 1371 of the structure according to an embodiment of the present technology, as a means for fixing the lens-attached substrates, adhesion using a resin is not used. For this reason, a resin for lens formation and a resin for substrate adhesion are not disposed between the lens-attached substrate and the lens-attached substrate. In addition, since a resin is not disposed on the upper surface and the lower surface of the lens-attached substrate, in the upper surface and the lower surface of the lens-attached substrate, a resin is neither thermally expanded nor curing-contracted.
Therefore, in the stacked lens structure 1371, even though the second lens-attached substrate 1362 and the third lens-attached substrate 1363 which are different in terms of lens thickness and substrate thickness are disposed on the upper layer and the lower layer of the first lens-attached substrate 1351, unlike the above-described Comparative Structure Examples 1 to 8, the bent state of the substrate caused by the curing-contraction and the bent state of the substrate caused by the thermal expansion do not occur.
Namely, due to the structure according to an embodiment of the present technology where the lens-attached substrates are fixed to each other by direct joining, it is possible to obtain a function or an effect that, even in the case where the lens-attached substrates which are different in terms of lens thickness and substrate thickness are stacked on the upper layer and the lower layer thereof, the bent state of the substrate can be more greatly suppressed than those of the above-described Comparative Structure Examples 1 to 8.
Hereinafter, other Modified Examples of the above-described embodiments will be described.
For example, in case of dicing a substrate-state stacked lens structure by using a blade or a laser, there is a problem in that chipping may be generated in a carrier substrate of each layer of lens-attached substrates. In addition, for example, if the chipping reaches through-holes, flexural strength of the lens-attached substrates is decreased, so that there is a problem in that the stacked lens structure may be broken at the time of assembling a camera module or the like.
In addition, in case of performing dicing by using blade dicing or the like, since the lens-attached substrates are stacked to have some thickness, the load of the dicing is increased, and thus, for example, process deviation occurs due to deterioration of the blade, so that there is a problem in that chipping yield is decreased.
Therefore, hereinafter, examples of chipping countermeasure will be described.
<First Chipping Countermeasure>
First, first chipping countermeasure will be described with reference to
In a stacked lens structure 1401, three layers of lens-attached substrates 1411a to 1411c are stacked. A lens resin portion 1422a is formed in an inner side of a through-hole 1423a of a carrier substrate 1421a of the lens-attached substrate 1411a. A light-shielding film 1425a is formed on a sidewall of the through-hole 1423a. A groove 1424a surrounding the through-hole 1423a is formed in an end portion of the upper surface of the carrier substrate 1421a.
The lens-attached substrates 1411b and 1411c have the same configuration as that of the lens-attached substrate 1411a, and thus, the description thereof is omitted. In addition, in
In addition, hereinafter, in the case where there is no need to individually distinguish the lens-attached substrates 1411a to 1411c, the lens-attached substrates are simply referred to as a lens-attached substrate 1411. Hereinafter, in the case where there is no need to individually distinguish the carrier substrates 1421a to 1421c, the carrier substrates are simply referred to as a carrier substrate 1421. Hereinafter, in the case where there is no need to individually distinguish the lens resin portions 1422a to 1422c, the lens resin portions are simply referred to as a lens resin portion 1422. Hereinafter, in the case where there is no need to individually distinguish the through-holes 1423a to 1423c, the through-holes are simply referred to as a through-hole 1423. Hereinafter, in the case where there is no need to individually distinguish the grooves 1424a to 1424c, the grooves are simply referred to as a groove 1424.
<Manufacturing Method for Stacked Lens Structure 1401>
Next, a manufacturing method for the stacked lens structure 1401 will be described with reference to
First, as illustrated in
In addition, by dry etching, grooves 1424a are formed on the upper surface of the carrier substrate 1421W-a to surround the respective through-holes 1423a.
The groove 1424a may be configured to surround each through-hole 1423a at least within the area surrounded by a dicing line (not shown). For example, a square or circle of the groove 1424a surrounding each through-hole 1423a may be formed within a square area surrounded by a dicing line. In addition, in both sides of each dicing line, grooves 1424a parallel to the dicing line may be formed so as to interpose the dicing line.
Next, as illustrated in
Next, as illustrated in
In this manner, the substrate-state lens-attached substrate 1411W-a is manufactured.
In addition by the same processes, the substrate-state lens-attached substrates 1411W-b and 1411W-c are manufactured.
Next, as illustrated in
Next, as illustration in
<Second Chipping Countermeasure>
Next, second chipping countermeasure will be described with reference to
In a stacked lens structure 1501, three layers of lens-attached substrates 1511a to 1511c are stacked. A lens resin portion 1522a is formed in an inner side of a through-hole 1523a of a carrier substrate 1521a of the lens-attached substrate 1511a. A light-shielding film 1525a is formed on a sidewall of the through-hole 1523a. A groove 1524a surrounding the through-hole 1523a is formed in an end portion of the upper surface of the carrier substrate 1521a.
The lens-attached substrates 1511b and 1511c have the same configuration as that of the lens-attached substrate 1511a, and thus, the description thereof is omitted. In addition, in
In addition, hereinafter, in the case where there is no need to individually distinguish the lens-attached substrates 1511a to 1511c, the lens-attached substrates are simply referred to as a lens-attached substrate 1511. Hereinafter, in the case where there is no need to individually distinguish the carrier substrates 1521a to 1521c, the carrier substrates are simply referred to as a carrier substrate 1521. Hereinafter, in the case where there is no need to individually distinguish the lens resin portions 1522a to 1522c, the lens resin portions are simply referred to as a lens resin portion 1522. Hereinafter, in the case where there is no need to individually distinguish the through-holes 1523a to 1523c, the through-holes are simply referred to as a through-hole 1523. Hereinafter, in the case where there is no need to individually distinguish the grooves 1524a to 1524c, the grooves are simply referred to as a groove 1524.
<Manufacturing Method for Stacked Lens Structure 1501>
Next, a manufacturing method for the stacked lens structure 1501 will be described with reference to
First, as illustrated in
In addition, by wet etching, grooves 1524a are formed on the upper surface of the carrier substrate 1521W-a to surround the respective through-holes 1523a.
The groove 1524a may be configured to surround each through-hole 1523a at least within the area surrounded by a dicing line (not shown). For example, a square or circle of the groove 1524a surrounding each through-hole 1523a may be formed within a square area surrounded by a dicing line. In addition, in both sides of each dicing line, grooves 1524a parallel to the dicing line may be formed so as to interpose the dicing line.
At this time, by using the above-described crystal anisotropic wet etching, a width of the groove 1524a is adjusted, so that a depth of the groove 1524a can be adjusted. For example, in case of a condition that etching is performed at 55° with respect to a crystal direction of the carrier substrate 1521W-a, if the width of the groove 1524a is set to be about 140 μm, the depth becomes about 100 μm.
In addition, the through-hole 1523a is also manufactured by using the crystal anisotropic wet etching, and thus, the through-hole 1523a and the groove 1524a can be simultaneously manufactured, so that it is possible to reduce the number of processes. In this case, slanted angles of the through-hole 1523a and the groove 1524a are equal to each other.
Next, as illustrated in
In this manner, the substrate-state lens-attached substrate 1511W-a is manufactured. In addition, the substrate-state lens-attached substrates 1511W-b and 1511W-c are manufactured by the same process.
Next, as illustrated in
Next, as illustration in
<Third Chipping Countermeasure>
Next, third chipping countermeasure will be described with reference to
In a stacked lens structure 1601, three layers of lens-attached substrates 1611a to 1611c are stacked. A lens resin portion 1622a is formed in an inner side of a through-hole 1623a of a carrier substrate 1621a of the lens-attached substrate 1611a.
The lens-attached substrates 1611b and 1611c have the same configuration as that of the lens-attached substrate 1611a, and thus, the description thereof is omitted. In addition, in
In addition, hereinafter, in the case where there is no need to individually distinguish the lens-attached substrates 1611a to 1611c, the lens-attached substrates are simply referred to as a lens-attached substrate 1611. Hereinafter, in the case where there is no need to individually distinguish the carrier substrates 1621a to 1621c, the carrier substrates are simply referred to as a carrier substrate 1621. Hereinafter, in the case where there is no need to individually distinguish the lens resin portions 1622a to 1622c, the lens resin portions are simply referred to as a lens resin portion 1622. Hereinafter, in the case where there is no need to individually distinguish the through-holes 1623a to 1623c, the through-holes are simply referred to as a through-hole 1623.
<Manufacturing Method for Stacked Lens Structure 1601>
Next, a manufacturing method for the stacked lens structure 1601 will be described with reference to
First, as illustrated in
Next, after the etching mask 1651 is removed, as illustrated in
Next, as illustrated in
In this manner, the substrate-state lens-attached substrate 1611W-a is manufactured. In addition, by the same processes, the substrate-state lens-attached substrates 1611W-b and 1611W-c are manufactured.
Next, by the above-described method, as illustrated in
Next, as illustrated in
In addition, according to the stacked structure of the lens-attached substrates, dicing is not performed, but the substrate may be diced by cleavage or the like.
<Modified Example of Manufacturing Method for Stacked Lens Structure 1601>
Next, Modified Example of a manufacturing method for the stacked lens structure 1601 will be described.
For example, as illustrated in
In addition, for example, as illustrated
More specifically, as illustrated in
Next, after the etching mask 1681 is removed, as illustrated in
In this manner, the processing of the through-hole 1623a and the processing of the groove 1682a are simultaneously performed, it is possible to shorten the processing time.
In addition, for example, as illustrated in
For example, as illustrated in
On the other hand, as illustrated in
In addition, the first to third chipping countermeasures described above are not limited to the stacked lens structure, but these countermeasures can be applied to the case of manufacturing a semiconductor device by stacking the carrier substrates and cutting the stacked substrate. For example, by stacking a substrate where a plurality of pixel array portions are disposed and a substrate where a plurality of control circuits performing control or the like of the pixel array portions are disposed and cutting the stacked substrate, these countermeasures can be applied to the case of manufacturing a solid-state imaging device where a pixel substrate and a control substrate are stacked.
In addition, for example, in the first or second chipping countermeasure, in the case where a plurality of patterns configured with predetermined circuits or parts are disposed in the carrier substrate, it is preferable that a groove surrounding each pattern is formed within an area surrounded by a dicing line.
The above-described camera module 1 can be used in a form where the camera module is incorporated into an electronic apparatus using a solid-state image device in an image acquisition unit (photoelectric conversion unit), for example, an imaging apparatus such as a digital still camera or a video camera, a mobile terminal apparatus having an imaging function, a copier using a solid-state imaging device in an image reading unit, or the like.
An imaging apparatus 2000 of
The image sensor 2001 in the camera module 2002 receives incident light (image light) from a subject and converts a light amount of the incident light focused on an imaging plane into an electrical signal in units of a pixel to output a pixel signal. The above-described camera module 1 is employed as the camera module 2002, and the image sensor 2001 corresponds to the above-described light-receiving device 12.
The display unit 2005 is configured with, for example, a panel-type display device such as a liquid crystal panel or an organic electro luminescence (EL) and displays a moving picture or a still image captured by the image sensor 2001. The recording unit 2006 records the moving picture or the still image captured by the image sensor 2001 in a recording medium such as a hard disk or a semiconductor memory.
The manipulation unit 2007 issues manipulation commands with respect to various functions of the imaging apparatus 2000 according to user's manipulation. The power supply unit 2008 appropriately supplies various powers which are operating powers of the DSP circuit 2003, the frame memory 2004, the display unit 2005, the recording unit 2006 and the manipulation unit 2007 to the respective components.
As described above, the camera module 1 equipped with the stacked lens structure 11 which are position-aligned at a high accuracy and joined (stacked) is used as the camera module 2002, so that it is possible to implement high image quality and miniaturization. Therefore, with respect to the imaging apparatus 2000 such as a video camera, a digital still camera, or a camera module for a mobile device such as a mobile phone, both of the miniaturization of a semiconductor package and the high quality of captured image can be achieved.
The technology according to an embodiment of the present disclosure may be applied to various products. For example, the technology according to an embodiment of the present disclosure may be applied to an internal information acquisition system for a patient, which uses an endoscopic capsule.
The configurations and functions of the endoscopic capsule 5401 and the external control device 5423 will be described in further detail. As illustrated in
The light source unit 5405 includes a light source such as a light-emitting diode (LED), for example, and irradiates the imaging field of the image capture unit 5407 with light.
The image capture unit 5407 includes an image sensor, and an optical system made up of multiple lenses provided in front of the image sensor. Reflected light (hereinafter called observation light) from the light used to irradiate a body tissue which is the object of observation is condensed by the optical system and incident on the image sensor. The image sensor receives and photoelectrically converts the observation light to thereby generate an electrical signal corresponding to the observation light, or in other words, an image signal corresponding to the observed image. The image signal generated by the image capture unit 5407 is provided to the image processing unit 5409. Note that various known image sensors such as a complementary metal-oxide-semiconductor (CMOS) image sensor or a charge-coupled device (CCD) image sensor may be used as the image sensor of the image capture unit 5407.
The image processing unit 5409 includes a processor such as a central processing unit (CPU) or a graphics processing unit (GPU), and performs various types of signal processing on the image signal generated by the image capture unit 5407. This signal processing may be a minimal level of processing (such as image data compression, frame rate conversion, data rate conversion, and/or format conversion, for example) for transmitting the image signal to the external control device 5423. Configuring the image processing unit 5409 to perform only a minimal necessary level of processing makes it possible to realize the image processing unit 5409 in a more compact form with lower power consumption, which is preferable for the endoscopic capsule 5401. However, if there is extra space or available power inside the housing 5403, additional signal processing (such as a noise removal process or other image quality-improving processes, for example) may also be performed by the image processing unit 5409. The image processing unit 5409 provides the image signal subjected to the signal processing to the wireless communication unit 5411 as raw data. Note that if information about the status (such as movement or orientation) of the endoscopic capsule 5401 is acquired by the status detection unit 5419, the image processing unit 5409 may also provide the image signal to the wireless communication unit 5411 in association with the information. This makes it possible to associate the position inside the body where an image is captured, the direction in which the image is captured and the like with the captured image.
The wireless communication unit 5411 includes a communication device capable of transmitting and receiving various types of information to and from the external control device 5423. This communication device includes, for example, an antenna 5413 and a processing circuit that performs processing such as modulation processing for transmitting and receiving signals. The wireless communication unit 5411 performs predetermined processing such as modulation processing on the image signal that was subjected to the signal processing by the image processing unit 5409, and transmits the image signal to the external control device 5423 via the antenna 5413. In addition, the wireless communication unit 5411 receives, from the external control device 5423 via the antenna 5413, a control signal related to driving control of the endoscopic capsule 5401. The wireless communication unit 5411 provides the received control signal to the control unit 5421.
The power supply unit 5415 includes, for example, an antenna coil for receiving power, a power regeneration circuit for regenerating power from a current produced in the antenna coil, and a voltage step-up circuit. In the power supply unit 5415, the principle of what is called contactless or wireless charging is used to generate power. Specifically, an external magnetic field (electromagnetic wave) of a predetermined frequency provided to the antenna coil of the power supply unit 5415 produces an induced electromotive force in the antenna coil. This electromagnetic wave may be a carrier wave transmitted from the external control device 5423 via an antenna 5425, for example. Power is regenerated from the induced electromotive force by the power regeneration circuit, and the electric potential of the power is suitably adjusted in the voltage step-up circuit, thereby generating power for power storage. The power generated by the power supply unit 5415 is stored in the power source unit 5417.
The power source unit 5417 includes a secondary battery, and stores power generated by the power supply unit 5415.
The status detection unit 5419 includes a sensor such as an acceleration sensor and/or a gyro sensor for detecting the status of the endoscopic capsule 5401. The status detection unit 5419 can acquire information about the status of the endoscopic capsule 5401 from detection results from the sensor. The status detection unit 5419 provides the acquired information about the status of the endoscopic capsule 5401 to the image processing unit 5409. As discussed earlier, in the image processing unit 5409, the information about the status of the endoscopic capsule 5401 may be associated with the image signal.
The control unit 5421 includes a processor such as a CPU, and centrally controls the operation of the endoscopic capsule 5401 by operating in accordance with a predetermined program. The control unit 5421 appropriately controls the driving of the light source unit 5405, the image capture unit 5407, the image processing unit 5409, the wireless communication unit 5411, the power supply unit 5415, the power source unit 5417, and the status detection unit 5419 in accordance with a control signal transmitted from the external control device 5423, thereby realizing the function of each component as described above.
The external control device 5423 may be a processor such as a CPU or GPU, or a device such as a microcontroller or a control board on which a processor and a storage element such as memory are mounted. The external control device 5423 includes the antenna 5425, and is capable of transmitting and receiving various types of information to and from the endoscopic capsule 5401 via the antenna 5425. Specifically, the external control device 5423 controls the operation of the endoscopic capsule 5401 by transmitting a control signal to the control unit 5421 of the endoscopic capsule 5401. For example, a light irradiation condition under which the light source unit 5405 irradiates a target of observation with light may be changed by a control signal from the external control device 5423. In addition, an image capture condition (such as the frame rate and the exposure level in the image capture unit 5407, for example) may be changed by a control signal from the external control device 5423. In addition, the content of processing in the image processing unit 5409 and a condition (such as the transmission interval and the number of images to transmit, for example) under which the wireless communication unit 5411 transmits the image signal may be changed by a control signal from the external control device 5423.
In addition, the external control device 5423 performs various types of image processing on the image signal transmitted from the endoscopic capsule 5401, and generates image data for displaying a captured internal image on a display device. For the image processing, various known signal processing, such as a development process (demosaicing process), an image quality-improving process (such as a band enhancement process, a super-resolution process, a noise reduction (NR) process, and/or a shake correction process), and/or an enlargement process (electronic zoom process), may be performed. The external control device 5423 controls the driving of a display device (not illustrated), and causes the display device to display a captured internal image on the basis of the generated image data. Alternatively, the external control device 5423 may also cause a recording device (not illustrated) to record the generated image data, or cause a printing device (not illustrated) to make a printout of the generated image data.
The above describes an example of the internal information acquisition system 5400 to which the technology according to an embodiment of the present disclosure may be applied. Among the configurations described in the foregoing, the technology according to an embodiment of the present disclosure may be applied favorably to an endoscopic capsule. Specifically, this invention is effective for downsizing an imaging device and reducing the burden on patients applying technology according to an embodiment of the present.
The image sensor configured as the camera module 1 can be used for various cases of sensing light such as visible light, infrared light, ultraviolet light, X-rays, for example, as follows.
Apparatuses capturing images provided for the use in appreciation such as a digital camera or a mobile apparatus with a camera function
Apparatuses provided for the use in traffic such as an on-vehicle sensor imaging front and rear sides, surroundings, inside of a vehicle, a surveillance camera monitoring running vehicles and roads, or a distance measuring sensor measuring distances between vehicles for the purpose of safe driving such as automatic stop or recognition of driver's state or the like
Apparatuses provided to home appliance such as a TV set, a refrigerator, or an air-conditioner to image user's gesture and manipulate the home appliance according to the gesture
Apparatuses provided for the use in medical care or health care such as an endoscope or an apparatus performing angiography by receiving infrared light
Apparatuses provided for the use in security such as a surveillance camera for crime prevention or a camera for person authentication
Apparatuses provided for the use in beauty such as a skin measurement instrument imaging skin or a microscope imaging scalp
Apparatuses provided for the use in sports such as an action camera dedicated to sports applications or a wearable camera
Apparatuses provided for the use in agriculture such as a camera for monitoring states of fields or crops
The embodiment of the present technique are not limited the above-described embodiments, but various changes are available within the scope without departing from the spirit of the present technique.
For example, the present technology is not limited to the application to the solid-state imaging device which detects a distribution of an incident amount of visible light and captures an image, but the present technology can be applied to a solid-state imaging device which captures a distribution of an incident amount of infrared light, X-rays, or particles or a solid-state imaging device (physical quantity distribution detection device) such as a fingerprint detection sensor which detects other physical quantities such as pressure or electrostatic capacitance and captures an image in a broad sense.
For example, the present technology may employ a combination of all or some of the above-described embodiments.
In addition, the effects disclosed in this specification are exemplary ones but not limited ones, and thus, there may be effects other than the effects disclosed in this specification.
In addition, the present technology may have the configurations as follows.
wherein a through-hole is formed in the pattern,
wherein a lens is disposed in an inner side of the through-hole, and
wherein the groove surrounds the through-hole.
1 Camera module
11 Stacked lens structure
12 Light-receiving device
13 Optical unit
21 Lens
41 (41a to 41e) Lens-attached substrate
43 Sensor substrate
51 Aperture stop plate
52 Aperture portion
81 Carrier substrate
82 Lens resin portion
83 Through-hole
121 Light-shielding film
122 Upper surface layer
123 Lower surface layer
141 Etching mask
142 Protective film
1401 Stacked lens structure
1411
a to 1411c Lens-attached substrate
1421
a to 1421c Carrier substrate
1422
a to 1422c Lens resin portion
1423
a to 1423c Through-hole
1424
a to 1424c Groove
1501 Stacked lens structure
1511
a to 1511c Lens-attached substrate
1521
a to 1521c Carrier substrate
1522
a to 1522c Lens resin portion
1523
a to 1523c Through-hole
1524
a to 1524c Groove
1601 Stacked lens structure
1611
a to 1611c Lens-attached substrate
1621
a to 1621c Carrier substrate
1622
a to 1622c Lens resin portion
1623
a to 1623c Through-hole
1652
a to 1652c, 1671a, 1682a, 1701a, 1711a to 1713a Groove
2000 Imaging apparatus
2001 Image sensor
2002 Camera module
Number | Date | Country | Kind |
---|---|---|---|
2015-152922 | Jul 2015 | JP | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/JP2016/003372 | 7/19/2016 | WO | 00 |