Patent Application
20130015545
The present disclosure relates to a solid-state imaging device, a manufacturing method of the solid-state imaging device and an electronic apparatus using the solid-state imaging device.
A CCD-type solid-state imaging device and a CMOS-type solid-state imaging device are heretofore known as solid-state imaging devices used for a digital still camera or a digital video camera. In these solid-state imaging devices, a light receiving unit is formed in each of plural pixels formed in a two dimensional matrix state, and signal charges are generated in accordance with an amount of received light in the light receiving unit. The signal charges generated in the light receiving unit are transferred and amplified, thereby obtaining an image signal.
In the solid-state imaging device, a microlens is generally provided in each pixel for allowing incident light to be efficiently incident on the light receiving unit. Recently, a structure in which microlenses having different refractive indexes corresponding to respective pixels are formed is proposed according to specifications of the solid-state imaging device.
For example, in JP-A-2009-198547 (Patent Document 1), there is disclosed a structure in which microlenses having different refractive indexes corresponding to respective pixels of R (red), G (green) and B (blue) are formed to thereby improve light condensing efficiency. In the technique described in Patent Document 1, a pattern of microlenses having different heights according to pixels is formed above a transparent resin layer by applying a thermal reflow process twice, and dry etching is performed to thereby form the transparent resin layer to have a desired microlens shape.
In JP-A-2009-109965 (Patent Document 2), there is disclosed a structure in which the curvature of microlenses is changed in a phase detection pixel and an imaging pixel to thereby change the refractive index in a solid-state imaging device applying a pupil-division phase difference system for autofocus detection (AF). In the technique described in Patent Document 2, a plane shape of microlenses is formed to be a rectangular in the imaging pixel and to be a circular in the phase detection pixel, thereby obtaining microlenses having different curvatures.
A surface shape, a formed position and the like of microlenses are affected by light condensing efficiency and the refractive index, therefore, a method of forming microlenses having different refractive indexes more accurately is requested.
In view of the above, it is desirable to provide a solid-state imaging device in which microlenses having different refractive indexes are formed in respective pixels accurately. It is also desirable to provide an electronic apparatus using the solid-state imaging device.
An embodiment of the present disclosure is directed to a solid-state imaging device including a substrate on which plural pixels having photoelectric converters are formed, an inorganic microlens made of an inorganic material and formed above the substrate, and an organic microlens made of an organic material and formed adjacent to the inorganic microlens so that a hem portion touches or overlaps a hem portion of the inorganic microlens.
In the solid-state imaging device according to the embodiment of the present disclosure, the inorganic microlens is made of the inorganic material and the organic microlens is made of the organic material, thereby allowing the inorganic microlens and the organic microlens to have different refractive indexes.
Another embodiment of the present disclosure is directed to a manufacturing method of a solid-state imaging device including forming plural pixels having photoelectric converters on a substrate, forming an inorganic microlens made of an inorganic material above a given pixel formed on the substrate, and forming an organic microlens made of an organic material above a pixel in which the inorganic microlens is not formed.
In the manufacturing method according to the embodiment of the present disclosure, the inorganic microlens made of an inorganic material excellent in light resistance as well as heat resistance is formed first. Accordingly, the organic microlens can be formed without reducing lens performance of the inorganic microlens. As a result, it is possible to form microlenses having different refractive indexes accurately.
Still another embodiment of the present disclosure is directed to an electronic apparatus including an optical lens, a solid-state imaging device having a substrate on which plural pixels having photoelectric converters are formed, an inorganic microlens made of an inorganic material and formed above the substrate, and an organic microlens made of an organic material and formed adjacent to the inorganic microlens so that a hem portion touches or overlaps a hem portion of the inorganic microlens, on which light condensed on the optical lens is incident, and a signal processing circuit processing output signals outputted from the solid-state imaging device.
According to the embodiments of the present disclosure, the solid-state imaging device in which microlenses having different refractive indexes are accurately formed can be obtained. It is also possible to obtain an electronic apparatus in which image quality is improved by applying the solid-state imaging device.
Hereinafter, examples of an electronic apparatus according to an embodiment of the present disclosure, a solid-state imaging device used for the electronic apparatus will be explained with reference to
1-1 Entire Structure of Solid-State Imaging Device
1-2 Structure of Relevant Part of Solid-State Imaging Device
1-3 Manufacturing Method of Solid-State Imaging
Device
2-1 Structure of Relevant Part of Solid-State Imaging Device
2-2 Manufacturing Method of Solid-State Imaging Device
A solid-state imaging device 1 according to the embodiment includes a pixel area 3 having plural pixels 2 arranged on a substrate 11 made of silicon, a vertical drive circuit 4, column signal processing circuits 5, a horizontal drive circuit 6, an output circuit 7, a control circuit 8 and so on.
Plural pixels 2 each have a photoelectric converter including a photodiode, and plural pixel transistors, which are regularly arranged on the substrate 11 in a two dimensional array. The pixel transistors may be four MOS transistors including a transfer transistor, a reset transistor, a selection transistor, an amplifier transistor or maybe three transistors including the above transistors other than the selection transistor.
The pixel area 3 includes the plural pixels 2 arranged regularly in the two dimensional array. The pixel area 3 has an effective pixel area in which light is actually received and signal charges generated by photoelectric conversion are amplified to be read to the column processing circuit 5 and a black-reference pixel area (not shown) for outputting optical black as a black level reference. The black-reference pixel area is normally formed at an outer peripheral portion of the effective pixel area.
The control circuit 8 generates clock signals, control signals and so on as operation references for the vertical drive circuit 4, the column signal processing circuits 5, the horizontal drive circuit 6 and the like based on a vertical synchronization signal, a horizontal synchronization signal and a master clock. The clock signals, the control signals and so on generated in the control circuit 8 are inputted into the vertical drive circuit 4, the column signal processing circuits 5, the horizontal drive circuit 6 and so on.
The vertical drive circuit 4 is formed by, for example, a shift register, selectively scanning respective pixels 2 in the pixel area 3 in units of rows sequentially in the vertical direction. Then, the vertical signal circuit 4 supplies pixel signals based on signal charges generated in accordance with an amount of received light in photodiodes of respective pixels 2 to the column signal processing circuits 5 through vertical signal lines.
The column signal processing circuits 5 are arranged with respect to respective columns of the pixels 2, performing signal processing such as noise reduction and signal amplification to signals outputted from pixels 2 of one row in units of pixel columns by using a signal from the black-reference pixel area (formed around the effective pixel area though not shown). Horizontal selection switches (not shown) are provided between the column signal processing circuits 5 and the horizontal signal line 10 at output stages of the column signal processing circuits 5.
The horizontal drive circuit 6 is formed by, for example, a shift register, sequentially selecting respective column signal processing circuits 5 by sequentially outputting a horizontal scanning pulse and allowing pixel signals to be outputted from respective column signal processing circuits 5 to the horizontal drive circuit 10.
The output circuit 7 performs signal processing to the signals sequentially supplied from respective column signal processing circuits 5 through the horizontal signal line 10 and outputs the signals.
The solid-state imaging device 1 according to the embodiment includes a substrate 12 on which plural pixels 2 each having a photodiode PD as a photoelectric converter are formed, a wiring layer 14, color filter layers 18, a planarization layer 19 and a stress relaxation layer 20. The solid-state imaging device 1 further includes an inorganic microlens 21 formed above the phase difference detection pixel 2b and an organic microlens 22 formed above the imaging pixel 2a.
The substrate 12 is formed by a semiconductor substrate made of, for example, silicon. On a surface of the substrate 12, a first-conductive type, for example, a p-type semiconductor well region 13 is formed. The photodiode PD forming the photoelectric converter and pixel transistors (not shown) are formed in each pixel on the surface side of the semiconductor well 13.
The photodiode PD is formed by a second-conductive type, for example, an n-type impurity region, generating and accumulating signal charges according to the amount of incident light. The signal charges generated and accumulated in the photodiode PD are read out pixel by pixel through not-shown pixel transistors.
The wiring layer 14 is formed on the surface side of the substrate 12, including wiring 16 stacked in plural layers (three layers in
Incidentally, the phase difference detection pixel 2b is a pixel outputting a phase difference detection signal for performing autofocus detection (AF). The autofocus function in the solid-state imaging device 1 according to the embodiment applies a pupil-division phase difference system obtaining two images by performing pupil division. Accordingly, light flux from a not-shown optical exit pupil provided on an upper portion of the solid-state imaging device 1 is separated by two phase difference detection pixels 2b and the phase difference between images outputted from the pair of phase difference detection pixels 2b is detected to thereby perform autofocus.
Additionally, the light shielding film 17 is formed for separating light flux from exit pupil regions in symmetrical positions. In the pair of phase difference detection pixels 2b, opening regions opened by the light shielding film 17 are provided in mirror symmetry.
The color filter layers 18 are formed over the wiring layer 14, which are made of a material selectively transmitting light of, for example, red (R), green (G) and blue (B) in respective pixels 2. The pixels 2 are formed by three primary colors of red (R), green (G) and blue (B) in
The planarization layer 19 is formed on the color filter layers 18 for planarizing the color filter layers 18 having different thicknesses according to the color as described above. Materials having permeability, heat resistance and so on are preferably used for the planarization layer 19, for example, an acrylic thermosetting resin material, a styrene resin material, an epoxy resin material and so on can be used. Furthermore, when the vertical structure of layers is allowed to be lower for improving light condensing characteristics of the solid-state imaging device 1, it is preferable to use an acrylic resin material, a styrene resin material, an epoxy resin material and so on having both a thermoplastic property and a thermosetting property.
The stress relaxation layer 20 is formed on the planarization film 19 for relaxing the difference in film stress between the planarization film 19 made of the above-described organic material and the inorganic microlens 21 made of a later-described material. The stress relaxation layer 20 is preferably made of an inorganic material as well as preferably formed by using a deposition method of a low-temperature CVD (Chemical Vapor Deposition) process. It is preferable to use any of silicon compounds, for example, represented by composition formulas SiO2 (hereinafter, SiO), Si3N4 (hereinafter SiN) or SixOy (0<x≦1, 0<y≦1, hereinafter written as SiON) as the stress relaxation layer 20.
The inorganic microlens 21 is formed on the stress relaxation layer 20 above the phase difference detection pixel 2b so that the surface thereof has a desirable curvature. The inorganic microlens 21 formed above the phase difference detection pixel 2b is made of an inorganic material, and it is preferable to use any of, for example, SiN, SiO and SiON.
Additionally, it is preferable that the phase difference detection pixel 2b is formed so that the focus position of incident light will be on the surface of the light shielding film 17 for obtaining the pupil-divided image as the phase difference detection signal. Accordingly, the inorganic microlens 21 formed above the phase difference detection pixel 2b is preferably made of an inorganic material with a higher refractive index than an organic material making the later-described organic microlens 22, which is preferably made of, for example, SiN or SiON. The microlens 21 is formed to have a curvature in which a focal point of incident light is on the surface of the light shielding film 17.
The organic microlens 22 is formed over the planarization film 19 above the imaging pixel 2a so that the surface thereof has a desired curvature. The organic microlens 22 formed above the imaging pixel 2a is made of an organic material, and preferably made of, for example, an acrylic resin material, a styrene resin material, an epoxy resin material or acrylic/styrene copolymerization resin material. Additionally, it is preferable that the imaging pixel 2a is formed so that the focus position will be on the surface of the substrate 12 for improving sensitivity. Accordingly, the organic microlens 22 formed above the imaging pixel 2a is formed to have a curvature in which a focal point of incident light is on the surface of the substrate 12.
As described above, the inorganic microlens 21 made of the inorganic material is formed above the phase difference detection pixel 2b in which a focal length is set to be shorter than in the imaging pixel 2a in the present embodiment. On the other hand, the organic microlens 22 made of the organic material is formed above the imaging pixel 2a in which the focal length is set to be longer than in the phase difference detection pixel 2b.
An antireflection film 23 is formed so as to cover surfaces of the inorganic microlenses 21 and the organic microlenses 22, which is formed for reducing reflection of light on the surface of the microlenses. As materials for the antireflection film 23, for example, a LTO (Low Temperature Oxide) film, SiON and the like can be used.
Incidentally, the film stress largely differs between the organic material layer and the inorganic material layer. Therefore, when the inorganic microlens 21 made of the inorganic material is stacked on the planarization film 19 made of the organic material so as to directly touch the film, wrinkles or distortion due to the difference in film stress occurs in the interface. That is, when the inorganic material layer and the organic material layer are stacked, problems due to the difference in film stress occur in the interface of stacked layers.
In response to the above, in a stacked body of the planarization film 19 made of the organic material and the inorganic microlens 21 made of inorganic material, the stress relaxation layer 20 having a stress value between film stress values of the organic material layer and the inorganic material layer as well as different from these values is formed. That is, in the present embodiment, the relation of the film stress will be the organic material layer<the stress relaxation layer<the organic material layer. Materials satisfying the condition will be used for the stress relaxation layer 20.
As described above, it is possible to relax the difference in film stress between the planarization film 19 and the inorganic microlens 21 formed above and below the stress relaxation layer 20 by providing the stress relaxation layer 20. Accordingly, occurrence of problems on the surface due to the difference in film stress can be suppressed even when the organic material layer and the inorganic material layer are stacked. As a result, problems of surface wrinkles or distortion generated on the interface of stacked layers can be suppressed, and pattern formation can be performed without problems in a subsequent lithography process. Therefore, it is possible to avoid deterioration of light condensing characteristics in the solid-state imaging device 1.
Materials applicable to the planarization film 19, the stress relaxation layer 20 and the inorganic microlens 21 have been described as the above. It is preferable to combine the above materials so that the planarization film 19 is formed by using an acrylic thermoplastic cured material and the inorganic microlens 21 is formed by using a low-temperature SiN film. As the stress relaxation layer 20 is formed by using the low-temperature SiON film in this case, the stress relaxation layer 20 (SiON) and an inorganic microlens layer 21a (SiN) can be formed continuously in the same CVD process without adding a new process, which simplifies the process.
As optical characteristics of the stress relaxation layer 20, it is preferable that the stress relaxation layer 20 has transparency with the refractive index of 1.4 to 2.0. Particularly, when the stress relaxation layer 20 is made of SiON, the refractive index is 1.6 to 1.9. Accordingly, the stress relaxation layer 20 can double as an antireflection film for reducing interface reflection between the inorganic microlens 21 made of SiN with the refractive index of 1.8 to 2.0 and the planarization film 19 made of an acrylic resin with the refractive index of 1.4 to 1.5. As a result, light condensing characteristics of the solid-state imaging device 1 is improved.
The film stress of the stress relaxation layer 20 is preferably −100 to 100 MPa. The film stress values shown here were measured by using a thin-film stress measuring apparatus (wafer-warpage measurement apparatus FSM 500TC (VISION, INC).
In the solid-state imaging device 1 having the above structure, signal charges corresponding to the amount of incident light are generated in the imaging pixels 2a to be outputted as pixel signals to thereby obtain an image. In the phase difference detection pixels 2b, pupil-divided images are obtained and the phase difference is detected, thereby performing autofocus. Plural pairs of phase difference detection pixels 2b which separate the light flux from exit pupil regions in symmetrical positions are provided in the pixel area 3 according to specifications of the solid-state imaging device. The phase difference detection pixels 2b can be provided in lines or can be arranged at random. Though the red pixel and the blue pixel are phase difference detection pixels 2b and the green pixel is the imaging pixel 2a in
In the solid-state imaging device 1 according to the embodiment, the inorganic microlens 21 is formed by using an inorganic material with a higher refractive index than an organic material forming the organic microlens 22 and is formed to have a curvature so that the focal point of incident light will be the surface of the light shielding film 17. Accordingly, light flux of an object transmitted through one region of a pair of partial regions of an imaging optical system (not shown) set on the light incident surface side of the solid-state imaging device 1 is incident on one of the pair of phase difference detection pixels 2b. On the other hand, light flux of the object transmitted through the other region of the pair of partial regions of the imaging optical system set on the light incident surface side of the solid-state imaging device 1 is incident on the other phase difference detection pixel 2b.
As described above, the light shielding film 17 is provided and the refractive index of the inorganic microlens 21 is adjusted so that a focal position of incident light is on the light shielding film 17 in the phase difference detection pixels 2b, therefore, desired light flux obtained by pupil division is incident on respective phase difference detection pixels 2b. Then, the phase difference can be detected by detecting the phase difference between images detected by the pair of phase difference detection pixels 2b.
Next, a manufacturing method of the solid-state imaging device 1 according to the embodiment will be explained.
First, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, an etching process is performed through the resist mask 24, thereby transferring the shape of the resist mask 24 onto the inorganic microlens layer 21a to form the organic microlenses 21 having a hemispherical shape as shown in
Next, as shown in
Next, thermal reflow is performed to the organic microlens layer 22a to thereby form the organic microlens 22 having the hemispherical shape as shown in
In the embodiment, the inorganic microlens 21 is made of an inorganic material excellent in heat resistance as well as light resistance. Accordingly, it is possible to form the organic microlens 22 without causing damages on the shape or the surface of the inorganic microlens 21. Therefore, lenses having different refractive indexes can be easily formed. As the inorganic microlens 21 is made of an inorganic material, the range of temperature setting for reflow can be expanded at the time of creating the organic microlens 22 made of an organic material.
When the inorganic microlenses 21 are formed so as to sandwich the organic microlens 22 made of an organic material as shown in
As described above, microlenses having different refractive indexes which are optimum respectively for the imaging pixel 2a and the phase difference detection pixel 2b can be formed, in which the optimum refractive index differs. The organic microlens 22 made of an organic material is formed after forming the inorganic microlens 21 made of an inorganic material, thereby forming two types of microlenses having different refractive indexes without impairing lens performance.
Though the example in which the phase difference detection pixels 2b for autofocus are formed at desired regions has been described in the embodiment, it is also preferable that the pixels are provided in a checkered pattern. When the pixels are provided in the checkered pattern, four sides of an area in which the organic microlens 22 is formed is surrounded by the inorganic microlenses 21, therefore, the slip of resin stops at hems of the microlenses made of the inorganic material when the reflow of the organic material is performed. As a result, the microlens made of the organic material can be accurately formed.
Next, a solid-state imaging device according to a second embodiment of the present disclosure will be explained.
The solid-state imaging device 30 according to the embodiment is an example in which the pixels 2 are in Bayer arrangement of red (R), green (G) and blue (B), and microlenses having different refractive indexes are formed according to the color of respective pixels 2. In the present embodiment, an inorganic microlens 31 is formed in a green pixel 2G, a first organic microlens 32 is formed in a blue pixel 2B and a second organic microlens 33 is formed in a red pixel 2R. The longer a light wavelength is, the smaller refractive index is. Accordingly, the size relation among a refractive index “n1” of the inorganic microlens 31, a refractive index “n2” of the first organic microlens 32 and a refractive index “n3” of the second organic microlens 33 is set to n1>n2>n3, thereby making adjustment so that focal positions of light incident on respective pixels are on the surface of the substrate 12.
First, the wiring layer 14, the color filter layers 18, the planarization layer 19 and the stress relaxation layer 20 are formed over the substrate 12 on which the pixels 2 are formed in the same manner as
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
As described above, the inorganic microlenses 31 made of the inorganic material are selectively formed above the green pixels 2G.
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
After that, as shown in
Though the solid-state imaging device 30 according to the embodiment has the structure in which the first organic microlens 32 and the second organic microlens 33 stop at the hem of the inorganic microlens 31, it is possible to perform reflow until the organic microlenses partially overlap the hem of the inorganic microlens 31. The shapes of the first organic microlens 32 and the second organic microlens 33 can be controlled at the time of reflow, therefore, various selection is possible.
As described above, the microlenses made of an inorganic material are formed in the checkered pattern first, then, the microlenses made of an organic material are formed at regions where the microlenses are not formed in the present embodiment. Accordingly, when the microlenses made of the organic material are formed, the microlenses made of the inorganic material are already formed around thereof. Accordingly, as the slip of the microlenses made of the organic material is suppressed by the microlenses made of the inorganic material, slip characteristics are relaxed and the controllability as well as the degree of freedom in shape are improved. As a result, lenses with desired refractive indexes can be easily formed. As the organic microlenses are formed at regions in which four sides are surrounded by the inorganic microlenses, the organic microlenses are formed in self alignment at the time of reflow.
The same advantages as the first embodiment can be also obtained.
The example in which the first organic microlens 32 and the second organic microlens 33 are formed after the inorganic microlens 31 is formed has been explained in the above embodiment, however, it is not limited to the example. It is also possible to form an inorganic microlens at a given position, after that, to form an inorganic microlens with a different refractive index at a different position, then, to form an organic microlens lastly.
The examples of the CMOS-type solid-state imaging device has been explained in the solid-state imaging devices according to the first and second embodiments, however, the present disclosure can be also applied to a CCD-type solid-state imaging device.
The present disclosure can be also applied to a solid-state imaging device which detects distribution of the incident amount of infrared light, X-ray or particles to image the distribution as an image, not limited to the solid-state imaging device which detects distribution of the incident amount of visible light to image the distribution as an image. In the broad sense, the present disclosure can be applied to the entire solid-state imaging devices (physical value distribution detector) such as a fingerprint detection sensor which detect distribution of other physical values such as pressure or capacitance to image the distribution as an image.
Furthermore, the present disclosure is not limited to the solid-state imaging device which sequentially scans respective unit pixels in the pixel area in units of rows and reads pixel signals from respective unit pixels. The present disclosure can be applied to an X-Y address type solid-state imaging device which selects arbitrary pixels in units of pixels and reads signals from the selected pixels in units of pixels.
The solid-state imaging device can be formed in a form of one-chip as well as in a module state having an imaging function in which the pixel area and a signal processing unit or an optical system are integrally packaged.
The present disclosure is not limited to the application to the solid-state imaging device but can be also applied to the imaging apparatuses. Here, the imaging apparatuses mean camera systems such as a digital still camera and a digital video camera, or electronic apparatuses having the imaging function such as a cellular phone device. The form of the module state mounted on the electronic apparatus, namely, a camera module may be called an imaging apparatus.
Next, an electronic apparatus according to a third embodiment of the present disclosure will be explained.
The electronic apparatus 200 according to the present embodiment includes a solid-state imaging device 1, an optical lens 201, a shutter device 202, a drive circuit 205 and a signal processing circuit 204. The electronic apparatus 200 according to the embodiment shows an embodiment in the case where the solid-state imaging device according to the first embodiment of the present disclosure described as the solid-state imaging device 1 is used for the electronic apparatus (camera).
The optical lens 201 forms image light (incident light) from an object on an imaging surface of the solid-state imaging device 1. Accordingly, signal charges are accumulated in the solid-state imaging device 1 in a fixed period of time. The shutter device 202 controls light irradiation period and a light shielding period with respect to the solid-state imaging device 1. The drive circuit 205 supplies drive signals controlling a transfer operation of the solid-state imaging device 1 and a shutter operation of the shutter device 202. The signal transfer of the solid-state imaging device 1 is performed by a drive signal (timing signal) supplied from the drive circuit 205. The signal processing circuit 204 performs various signal processing. A video signal to which signal processing is performed is stored in a storage medium such as a memory or outputted to a monitor.
In the electronic apparatus 200 according to the embodiment, lens characteristics of on-chip microlenses are improved and light condensing characteristics are improved in the solid-state imaging device 1, which improves image quality.
As the electronic apparatus 200 to which the solid-state imaging device 1 can be applied is not limited to the camera. The solid-state imaging device 1 can be applied to imaging apparatuses including a digital still camera and camera modules for mobile devices such as a cellular phone device.
The configuration in which the solid-state imaging device 1 according to the first embodiment is used for the electronic apparatus as the solid-state imaging device 1 has been explained in the embodiment, however, the solid-state imaging device manufactured according to the second embodiment can be also used.
The present disclosure may be implemented as the following configurations.
(1) A solid-state imaging device including a substrate on which plural pixels having photoelectric converters are formed,
an inorganic microlens made of an inorganic material and formed above the substrate, and
an organic microlens made of an organic material and formed adjacent to the inorganic microlens so that a hem portion touches or overlaps a hem portion of the inorganic microlens.
(2) The solid-state imaging device described in the above (1), further including
a planarization film made of an organic material and formed on the substrate, and
a stress relaxation layer of at least one layer or more between the planarization film and the inorganic microlens.
(3) The solid-state imaging device described in the above (1) or (2),
in which the inorganic microlens is made of any of Si3N4, SiO2 and SiON (0<X≦1, 0<Y≦1).
(4) The solid-state imaging device described in any of the above (1) to (3),
in which the stress relaxation layer is made of at least one or more materials selected from silicon compounds represented by Si3N4, SiO2 and SiON (0<X≦1, 0<Y≦1).
(5) The solid-state imaging device described in any of the above (1) to (4),
in which a refractive index of the stress relaxation layer is 1.4 to 2.0.
(6) The solid-state imaging device described in any of the above (1) to (5),
in which the stress relaxation layer doubles as an antireflection film.
(7) The solid-state imaging device described in any of the above (1) to (6),
in which the inorganic microlenses are formed above a pair of phase difference detection pixels detecting pupil-divided images and outputting phase difference detection signals,
the organic microlens is formed above an imaging pixel outputting an image signal of an object, and
a refractive index of the inorganic microlenses is higher than a refractive index of the organic microlens.
(8) A manufacturing method of a solid-state imaging device including
forming plural pixels having photoelectric converters on a substrate,
forming an inorganic microlens made of an inorganic material above a given pixel formed on the substrate, and
forming an organic microlens made of an organic material above a pixel in which the inorganic microlens is not formed.
(9) The manufacturing method of the solid-state imaging device described in the above (8),
in which the process of forming the organic microlens includes
forming an organic microlens layer made of an organic material above a given pixel by patterning and
deforming the organic microlens layer by thermal reflow.
(10) The manufacturing method of the solid-state imaging device described in the above (8) or (9),
in which the inorganic microlenses are formed in a checkered pattern.
(11) The manufacturing method of the solid-state imaging device described in any of the above (8) to (10), further including
forming a planarization film made of an organic material on the substrate, and
forming a stress relaxation layer at least one layer or more on the planarization film before the process of forming the inorganic microlens.
(12) The manufacturing method of the solid-state imaging device described in any of the above (8) to (11),
in which the inorganic microlens is made of any of Si3N4, SiO2 and SiON (0<X≦1, 0<Y≦1).
(13) The manufacturing method of the solid-state imaging device described in any of the above (8) to (12),
in which the stress relaxation layer is made of at least one or more materials selected from silicon compounds represented by Si3N4, SiO2 and SiON (0<X≦1, 0<Y≦1).
(14) The manufacturing method of the solid-state imaging device described in any of the above (8) to (13),
in which a refractive index of the stress relaxation layer is 1.4 to 2.0.
(15) The manufacturing method of the solid-state imaging device described in any of the above (8) to (14),
in which organic microlenses having different refractive indexes are formed by repeating the formation of the organic microlenses.
(16) An electronic apparatus including
an optical lens,
a solid-state imaging device having
a substrate on which plural pixels having photoelectric converters are formed,
an inorganic microlens made of an inorganic material and formed above the substrate, and
an organic microlens made of an organic material and formed adjacent to the inorganic microlens so that a hem portion touches or overlaps a hem portion of the inorganic microlens, on which light condensed on the optical lens is incident, and
a signal processing circuit processing output signals outputted from the solid-state imaging device.
The present disclosure contains subject matter related to that disclosed in Japanese Priority Patent Application JP 2011-153913 filed in the Japan Patent Office on Jul. 12, 2011, the entire contents of which are hereby incorporated by reference.
It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2011-153913 | Jul 2011 | JP | national |
