The present disclosure relates to a light emitting device and a method of manufacturing a light emitting device.
PTL 1 discloses an image display element and a method of manufacturing the same. The image display element is configured such that a plurality of micro light emitting elements is arranged on a drive circuit substrate in a two-dimensional array shape. The micro light emitting element is a light-emitting diode (LED) including a compound semiconductor.
In a method of manufacturing the image display element, a compound semiconductor is formed on a growth substrate through epitaxial growth. The compound semiconductor is divided into a plurality of pieces on the growth substrate, and electrodes and the like are formed at the plurality of compound semiconductors to form a plurality of micro light emitting elements. In addition, the growth substrate is caused to be opposed to the drive circuit substrate, and the plurality of micro light emitting elements on the growth substrate is joined to the drive circuit substrate. After they are joined, the growth substrate is removed.
Incidentally, crystal defects are more likely to occur at a compound semiconductor formed through epitaxial growth. Thus, from the viewpoint of yielding during manufacturing, a small-sized growth substrate is used. For example, a growth substrate having a size equal to or less than 6 inches is used. Thus, it is desired to develop a large-sized light emitting device having a size larger than that of the growth substrate.
The present disclosure provides a light emitting device that makes it possible to achieve an increase in size, and a method of manufacturing the light emitting device.
A light emitting device according to an embodiment of the present disclosure includes a light emitting body and a substrate. The light emitting body includes a plurality of light emitting elements and an insulating body in which the plurality of light emitting elements is embedded except for a light emitting surface of the plurality of light emitting elements. The plurality of light emitting elements is formed from a singulated compound semiconductor layer and is arranged in a row direction and a column direction. The substrate includes a drive circuit, a first terminal, and a second terminal and is joined to the light emitting body. The drive circuit drives the plurality of light emitting element. The first terminal and the second terminal electrically couple the drive circuit and the plurality of light emitting element to each other.
A method of manufacturing a light emitting device according to an embodiment of the present disclosure includes: forming a compound semiconductor layer obtained by causing a first compound semiconductor layer, an active layer, and a second compound semiconductor layer to sequentially grow on a growth substrate; forming a singulated compound semiconductor layer by dicing the growth substrate and the compound semiconductor layer; causing the second compound semiconductor layer to be opposed to a first joining surface of a first support substrate and joining the compound semiconductor layer to the first joining surface; peeling off the growth substrate; causing the first compound semiconductor layer to be opposed to a second joining surface of a second support substrate and joining the compound semiconductor layer to the second joining surface; removing the first support substrate; forming a plurality of light emitting elements from the singulated compound semiconductor layer; forming a light emitting body by forming an insulating body around the plurality of light emitting elements on the second support substrate; joining the second support substrate to a substrate on which a drive circuit, to which a first terminal and a second terminal are coupled, is mounted, in a state where the light emitting body is interposed between the substrate and the second support substrate and the second compound semiconductor layer is electrically coupled to the second terminal; removing the second support substrate; and electrically coupling the first compound semiconductor layer and the first terminal to each other.
Below, embodiments according to the present disclosure will be described in detail with reference to the drawings. Note that the description will be given in the following order.
A first embodiment is an example in which the present technology is applied to a light emitting device and a method of manufacturing the light emitting device.
A second embodiment is an example in which a structure of coupling a light emitting element and a drive circuit in the light emitting device according to the first embodiment is modified.
Third to sixth embodiments are examples in which a structure of a reflection attenuating film disposed between light emitting elements in the light emitting device according to the first embodiment is modified.
Seventh and eighth embodiments are examples in which a separation structure of the light emitting element in the light emitting device according to the first embodiment is modified.
A ninth embodiment is an example in which a structure of a light shielding film in the light emitting device according to the first embodiment is modified.
A first application example is an example in which the present technology is applied to a digital still camera. A second application example is an example in which the present technology is applied to a head-mounted display. A third application example is an example in which the present technology is applied to a television apparatus.
Here, an arrowed X direction illustrated in the drawings on an as-necessary basis is one direction of a planar direction of a light emitting device, directed from the left side on a paper surface toward the right side. An arrowed Y direction is perpendicular to the arrowed X direction and is another direction of the planar direction of the light emitting device, directed from the paper surface front side toward a direction going behind the paper surface. In addition, an arrowed Z direction is perpendicular to the arrowed X direction and the arrowed Y direction, and is a height direction of the light emitting device from the bottom side of the paper surface toward the upper side. The arrowed X direction, the arrowed Y direction, and the arrowed Z direction correspond to an X-axis direction, a Y-axis direction, and a Z-axis direction, respectively, in a three-dimensional coordinate system.
Note that these directions are illustrated to help understand the present technology, and are not given for the purpose of limiting the direction of the present technology.
(1) Overall Schematic Configuration of Light Emitting Device 1
As illustrated in
Furthermore, the light emitting device 1 includes, as main components, a substrate 20 included in the substrate region 2, and a light emitting body 35 disposed in the light emitting body region 3 and including a plurality of light emitting elements 30 arranged in the device arrangement region 7.
(2) Configuration of Substrate Region 2
The substrate region 2 is configured to include the substrate 20 and a drive circuit 21 mounted on a main surface of the substrate 20. Here, the main surface of the substrate 20 is one surface of the substrate 20 in which a semiconductor device such as a driving transistor is manufactured and the drive circuit 21 is formed.
For the substrate 20, a monocrystalline silicon (Si) substrate is used, for example. An insulating body 201 is provided on a rear surface of the substrate 20 located on an opposite side from the main surface, and also on side surfaces. For example, a silicon nitride (SiN) film or a silicon oxide (SiO) film may be practically used as the insulating body 201.
(2-1) Configuration of Drive Circuit 21
The drive circuit 21 is configured with a semiconductor device provided at a main surface portion of the substrate 20. The semiconductor device includes a complementary insulated gate field effect transistor (IGFET) 23 as the driving transistor. The insulated gate field effect transistor 23 at least includes both a field effect transistor (MISFET) having a metal/insulating body/semiconductor structure and a field effect transistor (MOSFET) having a metal/oxide film/semiconductor structure.
The insulated gate field effect transistor 23 is configured to include a channel formation region (substrate 20), a gate insulating film 231, a gate electrode 232, and paired n-type semiconductor regions 233 used as a source region and a drain region. The gate insulating film 231 is provided on the channel formation region. The gate electrode 232 is provided on the gate insulating film 231. The paired n-type semiconductor regions 233 are provided at main surface portions of the substrate 20 that are spaced apart in a channel length direction with the channel formation region being interposed therebetween.
Note that insulated gate field effect transistors of a p-channel conductive type differ only in terms of the conductive type of the semiconductor region, and the basic structure is the same. Thus, illustration of the insulated gate field effect transistor of the p-channel conductive type and explanation of the structure thereof will not be provided.
The drive circuit 21 is electrically coupled to each of a first terminal 281 and a second terminal 282 through a wiring layer 24. Here, the wiring layer 24 includes a plug wiring line 241, a first layer wiring line 242, a second layer wiring line 243, a third layer wiring line 244, and a plug wiring line 245.
The plug wiring line 241 is provided, for example, on the n-type semiconductor region 233 of the insulated gate field effect transistor 23, and one end (lower end) of the plug wiring line 241 is electrically coupled to the n-type semiconductor region 233. The plug wiring line 241 includes, for example, tungsten (W).
The first layer wiring line 242 is provided on the plug wiring line 241, and the first layer wiring line 242 is electrically coupled to another end (upper end) of the plug wiring line 241. The second layer wiring line 243 is provided on the first layer wiring line 242, and the second layer wiring line 243 is electrically coupled to the first layer wiring line 242. The third layer wiring line 244 is provided on the second layer wiring line 243, and the third layer wiring line 244 is electrically coupled to the second layer wiring line 243. The first layer wiring line 242 to the third layer wiring line 244 each include, for example, aluminum (Al) as a main composition.
In addition, an insulating body 25 is provided around the plug wiring line 241, between the first layer wiring line 242 and the second layer wiring line 243, between the second layer wiring line 243 and the third layer wiring line 244, and the like. The insulating body 25 includes, for example, a silicon oxide film or a silicon nitride film.
(2-2) Configuration of Second Light Shielding Film 26 and Second Light Absorbing Film 27
The third layer wiring line 244 is electrically coupled to the first terminal 281 or the second terminal 282 sequentially through the plug wiring line 245, a second light shielding film 26, and a second light absorbing film 27.
The second light shielding film 26 is disposed on the light emitting element 30 side of the insulated gate field effect transistor 23 that constitutes the drive circuit 21. Here, ends of the second light shielding film 26 extend in the planar direction to above the insulated gate field effect transistor 23. The second light shielding film 26 is disposed within the insulating body 25. The second light shielding film 26 blocks leakage light emitted from the light emitting element 30 toward the drive circuit 21 side, and is formed as an electrical path that electrically couples the drive circuit 21 and each of the first terminal 281 and the second terminal 282 to each other.
The second light shielding film 26 includes a single metal layer film including, as a main composition, aluminum, copper (Cu), tungsten, or titanium (Ti), for example.
The second light absorbing film 27 is disposed on the second light shielding film 26. Here, the second light absorbing film 27 is formed to have the same planar shape as the planar shape of the second light shielding film 26 as viewed from a direction perpendicular to the main surface of the substrate 20 (hereinafter, simply referred to as “plan view”). The second light absorbing film 27 is disposed within the insulating body 25. The second light absorbing film 27 absorbs leakage light emitted from the light emitting element 30 toward the drive circuit 21 side, and is formed as an electrical path that electrically couples the drive circuit 21 and each of the first terminal 281 and the second terminal 282 to each other.
The second light absorbing film 27 includes a single layer film including metal or a metallic compound including, as a main composition, titanium (TiN), cobalt (Co), nitrogen-doped titanium oxide (TiON), tantalum nitride (TaN), or amorphous carbon (a-C), for example.
(2-3) Configuration of First Terminal 281 and Second Terminal 282
The first terminal 281 and the second terminal 282 are disposed on the second light absorbing film 27 and also on the insulating body 25. Each of the first terminal 281 and the second terminal 282 is electrically coupled to the second light absorbing film 27.
The first terminal 281 is configured to be electrically coupled to one side (specifically, a first compound semiconductor layer 31) of the light emitting element 30. The second terminal 282 is configured to be electrically coupled to another side (specifically, a second compound semiconductor layer 32) of the light emitting element 30.
The first terminal 281 and the second terminal 282 include the same conductive material, for example, copper (Cu).
(3) Configuration of Light Emitting Body Region 3
As illustrated in
Here, the light emitting element 30 formed from the singulated compound semiconductor layer is a light emitting element formed from a compound semiconductor layer obtained by causing a compound semiconductor layer to grow on a growth substrate, dicing the growth substrate and the compound semiconductor layer, and separating them into individual divided pieces. The growth substrate singulated together with the compound semiconductor layer is removed in a manufacturing process. In the light emitting device 1 according to the present embodiment, one or a plurality of light emitting elements 30 is formed from the singulated compound semiconductor layer.
The light emitting body 35 further includes an insulating body 34 provided around the plurality of light emitting elements 30 except for the light emitting surface. The insulating body 34 includes, as a main composition, a silicon oxide film or a silicon nitride film.
(3-1) Configuration of Light Emitting Element 30
The light emitting element 30 is configured as a light-emitting diode (LED) including the first compound semiconductor layer 31, the second compound semiconductor layer 32, and an active layer 33. The second compound semiconductor layer 32 is disposed on the substrate region 2 side. The light emitting element 30 includes, as a main composition, a III-V compound semiconductor, and the second compound semiconductor layer 32 includes, for example, a p-type gallium nitride (p-GaN). The first compound semiconductor layer 31 includes, for example, an n-type gallium nitride (n-GaN).
(3-2) Configuration of First Light Reflecting Film 301
A first light reflecting film 301 is provided for each of the plurality of light emitting elements 30. The first light reflecting film 301 is provided to surround the light emitting element 30 along side surfaces of the first compound semiconductor layer 31, side surfaces of the active layer 33, side surfaces of the second compound semiconductor layer 32, and a surface, on the substrate region 2 side, of the second compound semiconductor layer 32. The first light reflecting film 301 is not provided on the light emitting surface that is a surface of the first compound semiconductor layer 31. The first light reflecting film 301 reflects, toward the light emitting surface side, light emitted from the light emitting element 30, thereby improving light extraction efficiency.
The first light reflecting film 301 has a constant film thickness along the side surfaces of the first compound semiconductor layer 31, the side surfaces of the active layer 33, the side surfaces of the second compound semiconductor layer 32, and the surface of the second compound semiconductor layer 32. To achieve this, the first light reflecting film 301 is formed by a chemical vapor deposition (CVD) method or an atomic layer deposition (ALD) method that provides favorable step coverage.
The first light reflecting film 301 includes, for example, metal such as aluminum or tungsten, or a metallic compound.
(3-3) Configuration of Transparent Electrode 311
As illustrated in
In the peripheral region 8, the transparent electrode 311 is electrically coupled to a first terminal 391 through a through wiring line 313. The through wiring line 313 is a wiring line extending in the thickness direction of the light emitting body 35 from the surface side of the light emitting body 35 toward the inside of the light emitting body 35. A specific material included in the through wiring line 313 will be described later.
At a position corresponding to the first terminal 281 of the substrate region 2, the first terminal 391 is provided at a surface, on the substrate region 2 side, of the light emitting body 35. The first terminal 391 is joined to and is electrically coupled to the first terminal 281. The first terminal 391 includes, for example, copper.
(3-4) Configuration of Reflection Attenuating Film 312
As illustrated in
The reflection attenuating film 312 is set such that a reflectance thereof at an interface with the transparent electrode 311 is lower than a light reflectance at an interface between the transparent electrode 311 and an insulting material of the insulating body 34. In addition, the reflection attenuating film 312 is formed such that a light transmittance thereof is lower than a light transmittance of the transparent electrode 311. Furthermore, the reflection attenuating film 312 has electrical conductivity, and is electrically coupled to the transparent electrode 311.
In the first embodiment, the reflection attenuating film 312 includes a combined film including a titanium nitride film 312A and a tungsten film 312B stacked on the titanium nitride film 312A. Here, for example, when the transparent electrode 311 is set to have a thickness of greater than or equal to 10 nm and less than or equal to 100 nm, the titanium nitride film 312A is set to have a thickness of greater than or equal to 3 nm and less than or equal to 50 nm, and the tungsten film 312B is set to have a thickness of greater than or equal to 50 nm and less than or equal to 200 nm.
In addition, the reflection attenuating film 312 may include a single layer film including, as a main composition, one or more metals selected from aluminum, titanium, tungsten, and copper, or may include a combined film including two or more layers. Furthermore, the reflection attenuating film 312 may include a metallic compound including the above-described metal as a main composition.
As illustrated in
(3-5) Configuration of Transparent Electrode 321
As illustrated in
(3-6) Configuration of Plug Wiring Line 36
In the device arrangement region 7, the transparent electrode 321 is electrically coupled to a second terminal 392 through a plug wiring line 36 provided directly below the transparent electrode 321 and for each of the light emitting elements 30. The plug wiring line 36 is a wiring line extending in the thickness direction of the light emitting body 35 from the surface side of the light emitting body 35 toward the inside of the light emitting body 35. One end portion of the plug wiring line 36 on the second compound semiconductor layer 32 side penetrates, in the thickness direction, through a portion of the first light reflecting film 301 provided along the second compound semiconductor layer 32, and is electrically coupled to the second compound semiconductor layer 32. Another end portion of the plug wiring line 36 on the substrate region 2 side is electrically coupled to the second terminal 392 with each of the first light absorbing film 37 and the first light shielding film 38 being interposed therebetween.
The plug wiring line 36 is formed by filling, with an electrically conductive material, a contact hole, without reference character, formed in the insulating body 34. That is, in plan view, the dimension of one end portion of the plug wiring line 36 matches the dimension of an opening of the contact hole. In a portion of the first light reflecting film 301 where the plug wiring line 36 penetrates through, the first light reflecting film 301 and the plug wiring line 36 are only necessary to be electrically separated from each other. Thus, in plan view, it is possible to set the dimension of the opening to be small. The plug wiring line 36 includes, for example, tungsten.
The second terminal 392 is provided at a position that corresponds to the second terminal 282 of the substrate region 2 at the surface of the light emitting body 35 on the substrate region 2 side. The second terminal 392 is joined to and is electrically coupled to the second terminal 282. The second terminal 392 includes, for example, copper, as with the first terminal 391.
(3-7) Configuration of First Light Absorbing Film 37 and First Light Shielding Film 38
Between the first light reflecting film 301 and the second terminal 392 or the second terminal 282 of the substrate region 2, the first light absorbing film 37 is provided at an outer periphery intersecting with the direction (arrowed Z direction) in which the plug wiring line 36 extends, here, in a planar direction (the arrowed X direction and the arrowed Y direction) perpendicular to the direction (arrowed Z direction) in which the plug wiring line 36 extends. In plan view, the first light absorbing film 37 is set to have the same dimension as the dimension of the opening of the portion of the first light reflecting film 301 where the plug wiring line 36 penetrates through, or to have a dimension larger than this dimension of the opening. The first light absorbing film 37 absorbs leakage light from a portion between the first light reflecting film 301 and the plug wiring line 36 toward the substrate region 2 side, and is formed as an electrical path that electrically couples the plug wiring line 36 and the second terminal 392 to each other. The first light absorbing film 37 is provided within the insulating body 25.
The first light absorbing film includes, for example, the same electrically conductive material as the second light absorbing film.
The first light shielding film 38 is provided below the first light absorbing film 37. The first light shielding film 38 has the same planar shape as the planar shape of the first light absorbing film 37 in plan view. The first light shielding film 38 is provided within the insulating body 25. The first light shielding film 38 blocks leakage light emitted from the light emitting element 30 toward the drive circuit 21 side, and is further formed as an electrical path, as with the first light absorbing film 37.
The first light shielding film 38 includes, for example, the same electrically conductive material as the second light shielding film 26, and includes a single metal layer film including, for example, tungsten or cobalt as a main composition.
(4) Configuration of Color Conversion Region 4
Returned to
The second light reflecting film 401 is provided along the periphery of side surfaces of the color conversion layer 40. The second light reflecting film 401 reflects light emitted from the light emitting element 30 and light diffused from the color conversion layer 40 to improve light extraction efficiency. The second light reflecting film 401 is formed, for example, using a method similar to that for the first light reflecting film 301, and includes, for example, the same material. Note that, in the first embodiment, the second light reflecting film 401 is separated from the reflection attenuating film 312 with an insulating film (no reference character is attached) being interposed therebetween.
In the color conversion region 4, a separation wall 41 is provided at a portion that is between adjacent second light reflecting films 401 and is between the color conversion layers 40 adjacent in the planar direction. The separation wall 41 is configured to separate the color conversion layers 40 from each other, and hold the color conversion layers 40. The separation wall 41 includes, for example, a silicon oxide film or a silicon nitride film.
(5) Configuration of Filter Region 5
The filter region 5 is provided on the color conversion region 4. The filter region 5 includes a filter 50. The filter 50 is provided on the color conversion layer 40, and blocks a particular emitted-light color emitted from the light emitting element 30 or absorbs the particular emitted-light color. Here, the particular emitted-light color is, for example, blue.
(6) Configuration of Optical System Region 6
An optical system region 6 is provided on the filter region 5. An on-chip lens 60 is provided in the optical system region 6. The on-chip lens 60 includes a plurality of convex lenses that is integrally formed. The convex lenses are each disposed for corresponding one of the light emitting elements 30. The on-chip lens 60 includes, for example, a resin material or an inorganic material.
(7) Configuration of Device Arrangement Region 7
As described above, in the device arrangement region 7, a plurality of light emitting elements 30 is arranged in a matrix in the planar direction. The plurality of light emitting elements 30 is formed from the singulated compound semiconductor layer. For example, the light emitting element 30 has a rectangular shape having a dimension of one side being greater than or equal to 0.5 μm and less than or equal to 20 in plan view.
(8) Configuration of Peripheral Region 8
In the peripheral region 8, the through wiring line 313 is disposed on the device arrangement region 7 side (inner side), and an external terminal 26P is provided on the outer side.
As described above, one end of the through wiring line 313 is electrically coupled to the first compound semiconductor layer 31 of the light emitting element 30 through the transparent electrode 311 and the reflection attenuating film 312. Another end of the through wiring line 313 is electrically coupled to the drive circuit 21 through the joining portion of the first terminal 391 and the first terminal 281.
The external terminal 26P is exposed from an opening extending from the filter region 5 into a portion of the substrate region 2. The external terminal 26P is electrically coupled to the drive circuit 21. The external terminal 26P is configured to allow a wire that is not illustrated in the drawing to be electrically coupled thereto. Through the wire, the external terminal 26P receives a drive signal that is inputted from the outside of the light emitting device 1 to the drive circuit 21. The external terminal 26P includes, for example, the same conductive material as the second light shielding film 26.
A method of manufacturing the light emitting device 1 according to the first embodiment includes the following manufacturing processes illustrated in
(1) Method of Manufacturing Light Emitting Body 35 and Light Emitting Body Region 3
First, a compound semiconductor layer 300 is formed on a growth substrate 10 (see
As illustrated in
Thereafter, in a state where the insulating film 341 is opposed to a dicing tape, and the growth substrate 10 is inverted, the growth substrate 10 is adhered to the dicing tape 11 (see
The singulated growth substrate 10, the singulated compound semiconductor layer 300, the singulated transparent electrode 321, and the singulated insulating film 341 are joined to a first joining surface 12A of a first support substrate 12 (see
As illustrated in
Thereafter, as illustrated in
As illustrated in
A second support substrate 13 is prepared. As illustrated in
As illustrated in
As illustrated in
Here, typically, the thickness of the second compound semiconductor layer 32 is thinner, by approximately one digit, than the thickness of the first compound semiconductor layer 31. Thus, by separating the compound semiconductor layer 300 from the second compound semiconductor layer 32 side, the accuracy of processing the active layer 33 is improved.
As illustrated in
As described above, the first light reflecting film 301 is formed to have a constant film thickness using a chemical vapor deposition method or an atomic layer deposition method.
As illustrated in
A contact hole (no reference character is attached) extending from the surface of the insulating film 343 and reaching the surface of the second compound semiconductor layer 32 of the light emitting element 30 is formed in the insulating film 343, and the plug wiring line 36 is formed in this contact hole (see
Thereafter, the first light absorbing film 37 and the first light shielding film 38 are formed sequentially on the plug wiring line 36 and the insulating film 343 (see
As illustrated in
As illustrated in
Here, the insulating film 341 to insulating film 345 constitute one insulating body 34, and the plurality of arranged light emitting elements 30 and the insulating body 34 formed around the light emitting elements 30 constitute the light emitting body 35 (see
(2) Method of Joining Light Emitting Body Region 3 and Substrate Region 2
As illustrated in
The drive circuit 21 is mounted at the main surface portion of the substrate 20 of the substrate region 2. Furthermore, in the substrate region 2, the wiring layer 24, the second light shielding film 26, the second light absorbing film 27, the first terminal 281, and the second terminal 282 are formed on the substrate 20. Joining is performed in a state where the first terminal 391 of the light emitting body region 3 is electrically coupled to the first terminal 281 of the substrate region 2 and the second terminal 392 of the light emitting body region 3 is electrically coupled to the second terminal 282 of the substrate region 2.
(3) Method of Manufacturing Transparent Electrode 311 and Reflection Attenuating Film 312
The second support substrate 13 is removed (see
Thereafter, as illustrated in
As illustrated in
The insulating film 346 is formed on the transparent electrode 311 (see
As illustrated in
As illustrated in
As illustrated in
In addition, through the same manufacturing process, the through wiring line 313 is formed within the opening 346B in the peripheral region 8. In the manufacturing method described here, the through wiring line 313 is electrically coupled to the second light shielding film 26 (corresponding to a first terminal according to the present disclosure) exposed in the opening 346B.
The reflection attenuating film 312 and the through wiring line 313 are formed, for example, by a sputtering method, and is processed into a predetermined shape by a dry etching process.
Through the manufacturing processes up to this point, the light emitting body region 3 joined to the substrate region 2 is completed.
(4) Method of Manufacturing Color Conversion Region 4, Filter Region 5, and Optical System Region 6
The separation wall 41 is formed between the light emitting elements 30 in the light emitting body region 3 (
As illustrated in
Thereafter, the color conversion layer 40 is formed on the light emitting element 30 in a region of which side surfaces are surrounded by the separation wall 41. The color conversion layer 40 includes a resin material (see
Once the color conversion layer 40 is formed, the color conversion region 4 is completed.
Note that, in a case where the light emitting device 1 is configured as a single-color light emitting device, the color conversion region 4 is not provided.
As illustrated in
The on-chip lens 60 is formed on the filter region 5 (see
As illustrated in
Once the series of these manufacturing processes ends, the method of manufacturing the light emitting device 1 according to the first embodiment ends, and the light emitting device 1 is completed.
(1) The light emitting device 1 according to the first embodiment includes the light emitting body 35 as illustrated in
For example, by forming the light emitting body 35 such that the plurality of light emitting elements 30 manufactured from a plurality of growth substrates 10 are arranged, it is possible to join the light emitting body 35 to the substrate 20 having a size larger than that of the growth substrate 10, thereby forming the light emitting device 1 having a size as large as the size of the substrate 20.
Thus, it is possible to provide the light emitting device 1 that makes it possible to achieve an increased size.
(2) In addition, in the light emitting device 1, as illustrated in
(3) In addition, the light emitting device 1 includes the first light reflecting film 301 as illustrated in
In addition, the first light reflecting film 301 has the constant film thickness. By reducing the film thickness of the first light reflecting film 301 provided along the surface, on the substrate 20 side, of the second compound semiconductor layer 32, the film thickness of the first light reflecting film 301 is reduced. The first light reflecting film 301 is provided along each of the side surfaces of the first compound semiconductor layer 31, the side surfaces of the active layer 33, and the side surfaces of the second compound semiconductor layer 32. Thus, it is possible to dispose the first light reflecting film 301 around the side surfaces of the light emitting element 30 even if the spacing between adjacent light emitting elements 30 is reduced, which makes it possible to improve the light extraction efficiency.
(4) In addition, in the light emitting device 1, as illustrated in
(5) Furthermore, the light emitting device 1 further includes the transparent electrode 311 and the reflection attenuating film 312, as illustrated in
Thus, as illustrated in
(6) In addition, in the light emitting device 1, as illustrated in
(7) Furthermore, in the light emitting device 1, as illustrated in
In other words, it is possible to form the reflection attenuating film 312 including the same conductive material (or using the same manufacturing processes) as the through wiring line 313 by using the through wiring line 313 formed in the peripheral region 8. This makes it possible to easily provide the reflection attenuating film 312.
(8) In addition, in the light emitting device 1, the reflection attenuating film 312 illustrated in
(9) Furthermore, the light emitting device 1 includes the color conversion layer 40 and the second light reflecting film 401 as illustrated in
This makes it possible to achieve a color light emitting device having high light extraction efficiency.
(10) In addition, in the light emitting device 1, as illustrated in
(11) Furthermore, the light emitting device 1 includes the plug wiring line 36 as illustrated in
(12) In addition, the light emitting device 1 includes the first light absorbing film 37 as illustrated in
(13) Furthermore, in the light emitting device 1, the first light absorbing film 37 illustrated in
(14) In addition, the light emitting device 1 includes the first light shielding film 38 as illustrated in
(15) Furthermore, in the light emitting device 1, the first light shielding film 38 illustrated in
(16) In addition, in the light emitting device 1, the drive circuit 21 includes the insulated gate field effect transistor 23 serving as the driving transistor, as illustrated in
This makes it possible to further reduce the leakage light emitted from the light emitting elements 30 toward the substrate 20 side.
(17) In addition, in the light emitting device 1, the second light shielding film 26 illustrated in
(18) Furthermore, in the method of manufacturing the light emitting device 1, first, the compound semiconductor layer 300 is formed as illustrated in
In such a method of manufacturing the light emitting device 1, the plurality of light emitting elements 30 is formed from the singulated compound semiconductor layer 300 (see
As one example, the light emitting elements 30 manufactured from the growth substrate 10 having a size of 4 inches to 6 inches are mounted on the substrate 20 having, for example, a size of 8 inches to 12 inches. This makes it possible to manufacture the light emitting device 1 having a size as large as the size of the substrate 20.
In addition, it is possible to select a non-defective light emitting element 30 to form the light emitting body 35, thereby mounting this light emitting body 35 on the substrate 20. This makes it possible to improve yield in manufacturing the light emitting device 1.
Moreover, the singulated compound semiconductor layer 300 is processed in a state of being joined to the second support substrate 13, to form the light emitting elements 30. The second support substrate 13 is joined to the substrate 20, and the light emitting element 30 is mounted on the substrate 20. Because the second support substrate 13 and the substrate 20 are each in a state of being a wafer, wafers are joined to each other. This makes it possible to improve accuracy of alignment at the time of joining.
(19) Furthermore, in the method of manufacturing the light emitting device 1, as illustrated in
Thus, the reflection attenuating film 312 is formed in the same process as the process of coupling the first compound semiconductor layer 31 and the first terminal 391 to each other, specifically, as the manufacturing process of forming the through wiring line 313. This makes it possible to reduce the number of manufacturing processes, as compared with a case where the reflection attenuating film 312 is formed through a different manufacturing process.
The light emitting device 1 according to the second embodiment of the present technology includes a through wiring line 361 that couples the first compound semiconductor layer 31 of the light emitting element 30 and the first terminal 391 to each other, as illustrated in
The through wiring line 361 includes the same electrically conductive material as the plug wiring line 36 that electrically couples the second compound semiconductor layer 32 and the second terminal 392 to each other. In addition, the through wiring line 361 is formed through a manufacturing process that is the same as the process of manufacturing the plug wiring line 36.
The light emitting device 1 according to the second embodiment makes it possible to achieve workings and effects similar to the workings and effects achievable by the light emitting device 1 according to the first embodiment.
In addition, the light emitting device 1 includes the through wiring line 361 as illustrated in
The light emitting device 1 according to the third embodiment of the present technology includes the reflection attenuating film 312 on the transparent electrode 311 between the light emitting elements 30 as illustrated in
As compared with the reflection attenuating film 312 according to the first embodiment, the reflection attenuating film 312 according to the third embodiment makes it possible to increase the area in which the transparent electrode 311 is joined. This makes it possible to further reduce the resistance value of the transparent electrode 311, and also makes it possible to reduce the film thickness of the transparent electrode 311.
The light emitting device 1 according to the fourth embodiment of the present technology includes the reflection attenuating film 312 on the transparent electrode 311 between the light emitting elements 30 as illustrated in
In the light emitting device 1 according to the fourth embodiment, the second light reflecting film 401 is coupled to the transparent electrode 311 with the reflection attenuating film 312 being interposed therebetween. Thus, the second light reflecting film 401 and the transparent electrode 311 are kept at the same electric potential.
The light emitting device 1 according to the fifth embodiment of the present technology includes the reflection attenuating film 312 on the transparent electrode 311 between the light emitting elements 30 as illustrated in
In the light emitting device 1 according to the fifth embodiment, the first light reflecting film 301 is coupled to the transparent electrode 311 with the reflection attenuating film 312 being interposed therebetween. Thus, the first light reflecting film 301 and the transparent electrode 311 are kept at the same electric potential.
Furthermore, in the light emitting device 1, a portion of the reflection attenuating film 312 is formed to penetrate through the transparent electrode 311 in the thickness direction as illustrated in
The light emitting device 1 according to the sixth embodiment of the present technology includes the reflection attenuating film 312 on the transparent electrode 311 between the light emitting elements 30 as illustrated in
In the light emitting device 1 according to the sixth embodiment, the first light reflecting film 301 and the second light reflecting film 401 are coupled to the transparent electrode 311 with the reflection attenuating film 312 being interposed therebetween. Thus, the first light reflecting film 301 and the second light reflecting film 401 are each kept at the same electric potential as the transparent electrode 311.
In the light emitting device 1 according to the seventh embodiment of the present technology, the light emitting elements 30 formed from the singulated compound semiconductor layer 300 (see
In order to suppress color mixture (crosstalk) between the adjacent light emitting elements 30, it is preferable that the adjacent light emitting elements 30 be separated from each other. However, if the spacing (pixel pitch) between the adjacent light emitting elements 30 is large enough to make the color mixture negligible, the light emitting elements 30 may not be separated from each other.
Note that, in the light emitting device 1 according to the seventh embodiment, a position at which the plug wiring line 36 and the first light absorbing film 37 are coupled to each other is offset relative to the position at which the first light shielding film 38 and the second terminal 392 are coupled to each other. This makes it possible to block a path of the leakage light from the light emitting element 30 toward the substrate 20 side, which makes it possible to further reduce leakage holes.
The light emitting device 1 according to the eighth embodiment of the present technology is a modification example of the light emitting device 1 according to the seventh embodiment. The light emitting device 1 includes a separation region 305 between the adjacent light emitting elements 30 as illustrated in
The light emitting device 1 according to the eighth embodiment makes it possible to achieve workings and effects similar to the workings and effects achievable by the light emitting device 1 according to the seventh embodiment.
The light emitting device 1 according to the ninth embodiment of the present technology is a modification example in which the light shielding structure of the light emitting device 1 according to the first embodiment is modified.
As illustrated in
In addition, in the light emitting body region 3, the light emitting device 1 includes a first light shielding film 381 between the second compound semiconductor layer 32 of the light emitting element 30 and the plug wiring line 36. A middle portion of the first light shielding film 381 is coupled to the second compound semiconductor layer 32 and the plug wiring line 36. A periphery portion of the first light shielding film 381, together with the plug wiring line 36, penetrates through the first light reflecting film 301, and has an increased diameter, as compared with the diameter of penetration of the first light reflecting film 301.
In addition, in the light emitting body region 3, the light emitting device 1 includes the through wiring line (plug wiring line) 361 between the light emitting elements 30. The through wiring line 361 electrically couples the first compound semiconductor layer 31 and the first terminal 391 to each other. A first light shielding film 382 having a structure similar to that of the first light shielding film 381 is provided at a portion at which the first compound semiconductor layer 31 and the through wiring line 361 are coupled to each other.
The light emitting device 1 according to the ninth embodiment makes it possible to achieve workings and effects similar to the working and effects achievable by the light emitting device 1 according to the first embodiment.
In addition, the light emitting device 1 includes the first light shielding film 381, the first light shielding film 382, and the second light shielding film 271. This makes it possible to effectively block the path of the leakage light from the light emitting element 30 toward the substrate 20, which makes it possible to further reduce the leakage light.
Next, application examples of the present technology will be described.
A monitor 1314 is provided at a position shifted toward the left side from the middle of the camera body portion 1311 as viewed from the back. An electronic viewfinder (eyepiece window) 1315 is provided above the monitor 1314. By looking into the electronic viewfinder 1315, the photographer visually recognizes an optical image of a subject that is guided from the image-capturing lens unit 1312, thereby being able to determine the composition. The electronic viewfinder 1315 includes the light emitting device 1.
The present technology is not limited to the embodiments described above, and various modifications are possible without departing from the gist of the present technology. For example, it is possible to combine two or more of the embodiments described above.
In addition, the present technology may be applied to a single-color light emitting device that does not include any color conversion region and a method of manufacturing the light emitting device.
In the present disclosure, a plurality of light emitting elements formed from a singulated compound semiconductor layer is arranged in a row direction and a column direction. The plurality of light emitting elements is embedded in an insulating body except for a light emitting surface, and a light emitting body is thus provided. The light emitting body is joined to a substrate including a drive circuit, a first terminal, and a second terminal. The first terminal and the second terminal electrically couple the drive circuit and the plurality of light emitting elements to each other. The light emitting device is thus manufactured. This eliminates restriction in terms of the size of a substrate on which the drive circuit is mounted due to the size of the growth substrate of the light emitting elements. This makes it possible to achieve an increase in the size of the light emitting device.
The present technology includes the following configurations.
(1)
A light emitting device including:
The light emitting device according to (1) described above, in which the plurality of light emitting elements includes a light-emitting diode including a first compound semiconductor layer, a second compound semiconductor layer, and an active layer, the first compound semiconductor layer being disposed on a side of the light emitting surface, the second compound semiconductor layer being disposed on a side of the substrate, the active layer being disposed between the first compound semiconductor layer and the second compound semiconductor layer.
(3)
The light emitting device according to (2) described above, further including a first light reflecting film provided along a side surface of the first compound semiconductor layer, a side surface of the active layer, a side surface of the second compound semiconductor, and a surface, on the side of the substrate, of the second compound semiconductor, the first light reflecting film having a constant film thickness, the first light reflecting film reflecting light emitted from the plurality of light emitting elements.
(4)
The light emitting device according to (3) described above, in which the first light reflecting film includes a metal film or a metallic compound film that is formed by a chemical vapor deposition method or an atomic layer deposition method.
(5)
The light emitting device according to any one of (1) to (4) described above, further including:
The light emitting device according to (5) described above, in which the reflection attenuating film has electrical conductivity, and is electrically coupled to the transparent electrode.
(7)
The light emitting device according to (6) described above, in which a portion of the reflection attenuating film is provided to penetrate the transparent electrode in a thickness direction.
(8)
The light emitting device according to (6) described above, in which
The light emitting device according to any one of (5) to (8) described above, in which the reflection attenuating film includes a single layer film or a combined film that includes one or more materials selected from tungsten, aluminum, titanium, tantalum, copper, and titanium nitride.
(10)
The light emitting device according to any one of (1) to (9) described above, further including:
The light emitting device according to (10) described above, in which an optical lens is disposed on the color conversion layer.
(12)
The light emitting device according to (3) described above, further including a plug wiring line having one end surface and another end surface in an extending direction, the one end surface penetrating the first light reflecting film in a thickness direction and being electrically coupled to the surface, on the side of the substrate, of the second compound semiconductor layer, the other end surface being electrically coupled to the second terminal.
(13)
The light emitting device according to (12) described above, further including a first light absorbing film provided at an outer periphery between the first light reflecting film and the second terminal, the outer periphery intersecting with the extending direction of the plug wiring line, the first light absorbing film absorbing leakage light from between the first light reflecting film and the plug wiring line toward the side of the substrate.
(14)
The light emitting device according to (13) described above, in which the first light absorbing film includes titanium nitride, cobalt, nitrogen-doped titanium oxide, tantalum nitride, or amorphous carbon.
(15)
The light emitting device according to (12) described above, further including a first light shielding film provided at an outer periphery between the first light reflecting film and the second terminal, the outer periphery intersecting with the extending direction of the plug wiring line, the first light shielding film blocking leakage light from between the first light reflecting film and the plug wiring line toward the side of the substrate.
(16)
The light emitting device according to (15) described above, in which the first light shielding film is provided to include aluminum, copper, tungsten, or titanium.
(17)
The light emitting device according to (15) described above, in which
The light emitting device according to (17) described above, in which the second light shielding film is provided to include aluminum, copper, tungsten, or titanium.
(19)
A method of manufacturing a light emitting device, the method including:
The method of manufacturing a light emitting device according to (19) described above, the method including:
A light emitting device including:
A light emitting device including:
This application claims the priority on the basis of Japanese Patent Application No. 2021-035604 filed on Mar. 5, 2021 with Japan Patent Office, the entire contents of which are incorporated in this application 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 |
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2021-035604 | Mar 2021 | JP | national |
Filing Document | Filing Date | Country | Kind |
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PCT/JP2022/007037 | 2/21/2022 | WO |