Light emitting device, projector and display

Abstract

The present invention provides a light-emitting device, a projector, and a display capable of shielding light emitted from a portion of a stacked body that overlaps with an outer edge of a first electrode when viewed from above. The light-emitting device comprises: a substrate; a stacked body disposed on the substrate and having a light-emitting layer; a first electrode that contacts the stacked body on a side of the stacked body opposite to the substrate and injects current into the light-emitting layer; and a wiring layer that is electrically connected to the first electrode and has a light-shielding property for light generated in the light-emitting layer, wherein a first opening portion is provided in the wiring layer for light emitted from the stacked body to pass through, and the first opening portion is located on the inner side of the outer edge of the first electrode when viewed from above.

Description

Technical Field

[0001] The invention relates to a light emitting device, a projector and a display. Background Art

[0002] Semiconductor lasers are expected to be the next generation of high-brightness light sources. In particular, semiconductor lasers using nanorods are expected to achieve high-output light emission at a narrow radiation angle due to the photonic crystal effect brought about by the nanorods.

[0003] For example, Patent Document 1 describes a semiconductor optical element array having a plurality of nanocolumns, which are composed of fine columnar crystals including an n-type cladding layer such as n-type AlGaN, an active layer, and a p-type semiconductor layer including a p-type cladding layer such as p-type AlGaN. P-side electrodes are provided on the plurality of nanocolumns.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2013-239718

[0005] In a semiconductor optical device array having a plurality of nanocolumns, there are nanocolumns that overlap with the outer edge of the p-side electrode in a plan view. Such nanocolumns may be cut by overetching when forming the p-side electrode, for example. Summary of the invention

[0006] One embodiment of the light-emitting device of the present invention comprises: a substrate; a stacked body, which is arranged on the substrate and has a light-emitting layer; a first electrode, which is in contact with the stacked body on the side of the stacked body opposite to the substrate and injects current into the light-emitting layer; and a wiring layer, which is electrically connected to the first electrode and has a light-shielding property for light generated in the light-emitting layer, and a first opening portion for passing light emitted from the stacked body is provided in the wiring layer, and the first opening portion is located on the inner side of the outer edge of the first electrode when viewed from above.

[0007] One aspect of a projector according to the present invention includes one aspect of the above-mentioned light emitting device.

[0008] One embodiment of a display according to the present invention includes one embodiment of the above-mentioned light-emitting device. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a cross-sectional view schematically showing the light emitting device of this embodiment.

[0010] Figure 2 It is a top view schematically showing the light emitting device of this embodiment.

[0011] Figure 3 It is a cross-sectional view schematically showing the light emitting device of this embodiment.

[0012] Figure 4It is a cross-sectional view schematically showing the manufacturing process of the light emitting device of this embodiment.

[0013] Figure 5 It is a cross-sectional view schematically showing the manufacturing process of the light emitting device of this embodiment.

[0014] Figure 6 It is a cross-sectional view schematically showing the manufacturing process of the light emitting device of this embodiment.

[0015] Figure 7 It is a cross-sectional view schematically showing a light emitting device according to a modified example of the present embodiment.

[0016] Figure 8 It is a plan view schematically showing a light emitting device according to a modification example of the present embodiment.

[0017] Fig. 9 It is a diagram schematically showing a projector according to this embodiment.

[0018] Fig.10 It is a top view schematically showing the display according to this embodiment.

[0019] Fig.11 It is a cross-sectional view schematically showing the display according to this embodiment.

[0020] Description of symbols

[0021] 10: substrate; 20: laminate; 22: buffer layer; 30: columnar portion; 30a: first columnar portion; 32: first semiconductor layer; 34: light emitting layer; 36: second semiconductor layer; 40: insulating layer; 42: second opening; 44: side; 50: first electrode; 52: side; 54: outer edge; 60: second electrode; 70: third electrode; 80: wiring layer; 82: first opening; 84: side; 86: annular portion; 88: extension portion; 90: resist layer; 100: light emitting device; 100R: red light source; 100G: green light source; 100B: blue light Source; 200: light emitting device; 800: projector; 802R: first optical element; 802G: second optical element; 802B: third optical element; 804R: first light modulating device; 804G: second light modulating device; 804B: third light modulating device; 806: cross-color separation prism; 808: projection device; 810: screen; 900: display; 910: circuit substrate; 912: display area; 914: data line driving circuit; 916: scanning line driving circuit; 918: control circuit; 920: lens array; 922: lens; 930: heat sink. DETAILED DESCRIPTION

[0022] Hereinafter, preferred embodiments of the present invention will be described in detail using the accompanying drawings. In addition, the embodiments described below do not unduly limit the contents of the present invention described in the claims. In addition, all structures described below are not necessarily essential structural elements of the present invention.

[0023] 1. Light-emitting device

[0024] 1.1. Overall structure

[0025] First, a light emitting device according to this embodiment will be described with reference to the drawings. Figure 1 2 is a cross-sectional view schematically showing the light emitting device 100 according to the present embodiment. Figure 2 is a top view schematically showing the light emitting device 100 of this embodiment. Figure 1 yes Figure 2 Line II cross-sectional view.

[0026] like Figure 1 and Figure 2 As shown, the light emitting device 100 includes, for example, a substrate 10, a laminate 20, an insulating layer 40, a first electrode 50, a second electrode 60, a third electrode 70, and a wiring layer 80. Figure 2 The second electrode 60 is omitted in the figure. The light emitting device 100 is, for example, a semiconductor laser.

[0027] The substrate 10 is, for example, a Si substrate, a GaN substrate, a sapphire substrate, a SiC substrate, or the like.

[0028] The laminate 20 is provided on the substrate 10. Figure 1 In the example shown, the laminated body 20 is provided on the substrate 10. The laminated body 20 has a buffer layer 22 and a columnar portion 30, for example.

[0029] In this specification, in the stacking direction of the stacked body 20 (hereinafter, also referred to as the "stacking direction"), the direction from the light emitting layer 34 toward the second semiconductor layer 36 is set as "upward" and the direction from the light emitting layer 34 toward the first semiconductor layer 32 is set as "downward" for description. In addition, the direction orthogonal to the stacking direction is also referred to as the "in-plane direction". In addition, the "stacking direction of the stacked body 20" refers to the stacking direction of the first semiconductor layer 32 and the light emitting layer 34 of the columnar portion 30. In addition, "when viewed from above" refers to the case of observing from the stacking direction.

[0030] The buffer layer 22 is provided on the substrate 10. The buffer layer 22 is a semiconductor layer of the first conductivity type. The buffer layer 22 is, for example, an n-type GaN layer doped with Si. Although not shown, a mask layer for forming the columnar portion 30 is provided on the buffer layer 22. The mask layer is, for example, a silicon oxide layer, a titanium layer, a titanium oxide layer, an aluminum oxide layer, etc.

[0031] The columnar portion 30 is provided on the buffer layer 22. The columnar portion 30 has a columnar shape protruding upward from the buffer layer 22. In other words, the columnar portion 30 protrudes upward from the substrate 10 via the buffer layer 22. The columnar portion 30 is also called, for example, a nanocolumn, a nanowire, a nanorod, or a nanopillar. The planar shape of the columnar portion 30 is, for example, a polygon or a circle.

[0032] The diameter of the columnar portion 30 is, for example, not less than 50 nm and not more than 500 nm. By setting the diameter of the columnar portion 30 to not more than 500 nm, a high-quality crystalline light-emitting layer 34 can be obtained, and the strain inside the light-emitting layer 34 can be reduced. Thus, the light generated in the light-emitting layer 34 can be efficiently amplified.

[0033] In addition, the “diameter of the columnar portion” refers to the diameter when the planar shape of the columnar portion 30 is a circle, and refers to the diameter of the smallest circle when the planar shape of the columnar portion 30 is a non-circular shape. For example, when the planar shape of the columnar portion 30 is a polygon, the diameter of the columnar portion 30 is the diameter of the smallest circle that includes the polygon inside, and when the planar shape of the columnar portion 30 is an ellipse, the diameter of the columnar portion 30 is the diameter of the smallest circle that includes the ellipse inside.

[0034] A plurality of columnar portions 30 are provided. The interval between adjacent columnar portions 30 is, for example, greater than 1 nm and less than 500 nm. The plurality of columnar portions 30 are arranged at a predetermined pitch in a predetermined direction when viewed from above. The plurality of columnar portions 30 are, for example, arranged in a triangular lattice or a square lattice. The plurality of columnar portions 30 can exhibit the effect of a photonic crystal.

[0035] In addition, the "pitch between columnar portions" refers to the distance between the centers of the columnar portions 30 adjacent to each other in a predetermined direction. The "center of the columnar portion" is the center of the circle when the planar shape of the columnar portion 30 is a circle, and is the center of the smallest circle when the planar shape of the columnar portion 30 is a non-circular shape. For example, when the planar shape of the columnar portion 30 is a polygon, the center of the columnar portion 30 is the center of the smallest circle that includes the polygon inside, and when the planar shape of the columnar portion 30 is an ellipse, the center of the columnar portion 30 is the center of the smallest circle that includes the ellipse inside.

[0036] The columnar portion 30 includes a first semiconductor layer 32 , a light emitting layer 34 , and a second semiconductor layer 36 .

[0037] The first semiconductor layer 32 is disposed on the buffer layer 22. The first semiconductor layer 32 is disposed between the substrate 10 and the light emitting layer 34. The first semiconductor layer 32 is a semiconductor layer of the first conductivity type. The first semiconductor layer 32 is, for example, an n-type GaN layer doped with Si.

[0038] The light emitting layer 34 is disposed on the first semiconductor layer 32. The light emitting layer 34 is disposed between the first semiconductor layer 32 and the second semiconductor layer 36. The light emitting layer 34 generates light by injecting current. The light emitting layer 34 has, for example, a well layer and a barrier layer. The well layer and the barrier layer are i-type semiconductor layers that are not intentionally doped with impurities. The well layer is, for example, an InGaN layer. The barrier layer is, for example, a GaN layer. The light emitting layer 34 has an MQW (Multiple Quantum Well: multiple quantum well) structure consisting of a well layer and a barrier layer.

[0039] It should be noted that there is no particular limitation on the number of well layers and barrier layers constituting the light emitting layer 34. For example, only one well layer may be provided, in which case the light emitting layer 34 has an SQW (Single Quantum Well) structure.

[0040] The second semiconductor layer 36 is provided on the light emitting layer 34. The second semiconductor layer 36 is a semiconductor layer of a second conductivity type different from the first conductivity type. The second semiconductor layer 36 is, for example, a p-type GaN layer doped with Mg. The first semiconductor layer 32 and the second semiconductor layer 36 are cladding layers having a function of confining light in the light emitting layer 34.

[0041] Although not shown in the figure, an OCL (Optical Confinement Layer) composed of an i-type InGaN layer and a GaN layer may be provided at least one between the first semiconductor layer 32 and the light emitting layer 34, and between the light emitting layer 34 and the second semiconductor layer 36. In addition, the second semiconductor layer 36 may also have an EBL (Electron Blocking Layer) composed of a p-type AlGaN layer.

[0042] In the light emitting device 100, a pin diode is formed by the p-type second semiconductor layer 36, the i-type light emitting layer 34, and the n-type first semiconductor layer 32. In the light emitting device 100, if a forward bias voltage of the pin diode is applied between the first electrode 50 and the third electrode 70, current is injected into the light emitting layer 34, and recombination of electrons and holes occurs in the light emitting layer 34. Light emission is generated by this recombination. The light generated by the light emitting layer 34 propagates in the in-plane direction, forms a standing wave by the effect of the photonic crystal generated by the plurality of columnar portions 30, and receives gain in the light emitting layer 34 to perform laser oscillation. Then, the light emitting device 100 emits the +1st order diffracted light and the -1st order diffracted light as laser light in the stacking direction.

[0043] In addition, although not shown, a reflective layer may be provided between the substrate 10 and the buffer layer 22, or below the substrate 10. The reflective layer is, for example, a DBR (Distributed Bragg Reflector) layer. The reflective layer can reflect the light generated in the light-emitting layer 34, and the light-emitting device 100 can emit light only from the first electrode 50 side.

[0044] The insulating layer 40 covers the laminate 20. In the example shown in the figure, the insulating layer 40 covers a portion of the buffer layer 22, a portion of the plurality of columnar portions 30, and a portion of the first electrode 50. The thickness of the insulating layer 40 is, for example, 1 μm or more. The insulating layer 40 is, for example, a polyimide layer, a silicon oxide layer, or the like.

[0045] The first electrode 50 is disposed on the second semiconductor layer 36. The first electrode 50 is electrically connected to the second semiconductor layer 36. The second semiconductor layer 36 may be in ohmic contact with the first electrode 50.

[0046] The second electrode 60 is provided on the first electrode 50 and the insulating layer 40. The first electrode 50 and the second electrode 60 are electrodes for injecting current into the light emitting layer 34. The first electrode 50 and the second electrode 60 will be described in detail later.

[0047] The third electrode 70 is provided on the buffer layer 22. The buffer layer 22 may also be in ohmic contact with the third electrode 70. The third electrode 70 is electrically connected to the first semiconductor layer 32. In the example shown in the figure, the third electrode 70 is electrically connected to the first semiconductor layer 32 via the buffer layer 22. The third electrode 70 is another electrode for injecting current into the light emitting layer 34. The third electrode 70 is, for example, a laminated body in which a Cr layer and a Ni layer are laminated from the buffer layer 22 side.

[0048] The wiring layer 80 is provided on the second electrode 60 and the insulating layer 40. The wiring layer 80 is electrically connected to the first electrode 50 via the second electrode 60. The wiring layer 80 will be described in detail later.

[0049] In the above description, the light emitting layer 34 of the InGaN system is described, but various material systems that can emit light by injecting current according to the wavelength of the emitted light can be used as the light emitting layer 34. For example, semiconductor materials such as AlGaN system, AlGaAs system, InGaAs system, InGaAsP system, InP system, GaP system, and AlGaP system can be used.

[0050] In the above description, a gap is provided between adjacent columnar portions 30, but the stacked body 20 may include a light propagation layer for propagating light generated in the light emitting layer 34 between adjacent columnar portions 30. The light propagation layer is, for example, a silicon oxide layer, an aluminum oxide layer, or a titanium oxide layer.

[0051] In the above description, an example in which the stacked body 20 has a plurality of columnar portions 30 is described. However, the stacked body 20 may not have a plurality of columnar portions 30 but may be composed of a film-like first semiconductor layer 32 , a film-like light-emitting layer 34 , and a film-like second semiconductor layer 36 .

[0052] In addition, the light emitting device 100 is not limited to a laser, and may be an LED (Light Emitting Diode).

[0053] 1.2. Wiring layer and electrodes, etc.

[0054] The wiring layer 80 is provided with a first opening 82. Figure 2 In the example shown, the shape of the first opening 82 is a circle. The first opening 82 is defined by the side surface 84 of the wiring layer 80. The first opening 82 passes through the wiring layer 80. The first opening 82 is an opening for light emitted from the laminate 20 to pass through. In the example shown in the figure, the wiring layer 80 has a ring-shaped ring portion 86 and an extension portion 88 extending outward from the ring portion 86. Although not shown in the figure, the extension portion 88 is connected to, for example, wire bonding or FPC (Flexible printed circuits).

[0055] The wiring layer 80 has a light shielding property for light generated in the light emitting layer 34. Therefore, the wiring layer 80 shields light emitted from the stacked body 20. The wiring layer 80 does not transmit light emitted from the stacked body 20. The transmittance of the wiring layer 80 for light generated in the light emitting layer 34 is lower than the transmittance of the first electrode 50 for light generated in the light emitting layer 34.

[0056] The resistivity of the wiring layer 80 is lower than the resistivity of the second electrode 60. The wiring layer 80 is a metal wiring layer. The wiring layer 80 is, for example, a laminated body in which a Cr layer, a Ni layer, and an Au layer are laminated from the insulating layer 40 side. The thickness of the Cr layer is, for example, 20 nm. The thickness of the Ni layer is, for example, 30 nm. The thickness of the Au layer is, for example, 200 nm. If the thickness of the wiring layer 80 is 200 nm or more, light emitted from the laminated body 20 can be more reliably shielded.

[0057] The insulating layer 40 is provided with a second opening 42. Figure 2In the example shown, the second opening 42 is in the shape of a circle. The second opening 42 passes through the insulating layer 40. The second opening 42 is defined by the side surface 44 of the insulating layer 40. Moreover, the bottom surface of the second opening 42 is defined by the upper surface of the first electrode 50. The second electrode 60 is provided on the side surface 44. In the example shown, the wiring layer 80 is not provided in the second opening 42. When viewed from above, the area of ​​the second opening 42 is smaller than the area of ​​the first opening 82, and the second opening 42 completely overlaps with the first opening 82.

[0058] The first electrode 50 is provided on the side of the laminate 20 opposite to the substrate 10. The first electrode 50 is in contact with the laminate 20. The first electrode 50 is provided between the laminate 20 and the second electrode 60.

[0059] Here, Figure 3 Schematically shows a cross-sectional view of the side surface 52 of the first electrode 50. Figure 3 In FIG. 5 , the components other than the columnar portion 30 and the first electrode 50 are omitted. Figure 3 As shown, the first columnar portion 30a among the plurality of columnar portions 30 has a portion covered by the first electrode 50 and a portion not covered by the first electrode 50. The first columnar portion 30a is disposed below the side surface 52 of the first electrode 50. The first columnar portion 30a overlaps with the outer edge 54 of the first electrode 50 when viewed from above. The entire first columnar portion 30a overlaps with the wiring layer 80 when viewed from above. Figure 2 As shown, the first opening 82 and the second opening 42 are located inside the outer edge 54 in a plan view. The outer edge 54 overlaps with the wiring layer 80 in a plan view. In the example shown in the figure, the entire outer edge 54 overlaps with the wiring layer 80 in a plan view. The side surface 52 of the first electrode 50 constitutes the outer edge 54, for example.

[0060] The resistivity of the first electrode 50 is lower than the resistivity of the second electrode 60. The first electrode 50 transmits light emitted from the stacked body 20. The thickness of the first electrode 50 is, for example, 5 nm or more and 50 nm or less, preferably 10 nm or more and 30 nm or less. If the thickness of the first electrode 50 is 5 nm or more, the resistance can be reduced. If the thickness of the first electrode 50 is 50 nm or less, the transmittance of light generated in the light emitting layer 34 can be increased.

[0061] The first electrode 50 is, for example, a stack of a Pd layer, a Pt layer, and an Au layer stacked from the second semiconductor layer 36 side. The thickness of the Pd layer is, for example, 5 nm. The thickness of the Pt layer is, for example, 5 nm. The thickness of the Au layer is, for example, 10 nm. Alternatively, the first electrode 50 may be a stack of a Ni layer and an Au layer stacked from the second semiconductor layer 36 side.

[0062] The second electrode 60 is in contact with the first electrode 50. The second electrode 60 is not in contact with the laminate 20. The second electrode 60 is provided in the second opening 42. In the example shown in the figure, the second electrode 60 is provided on the upper surface of the insulating layer 40, the side surface 44 of the insulating layer 40 defining the second opening 42, and the upper surface of the first electrode 50. The second electrode 60 is connected to the first electrode 50 exposed through the second opening 42. The planar shape of the second electrode 60 is, for example, a circle.

[0063] The transmittance of the second electrode 60 to the light generated in the light-emitting layer 34 is higher than the transmittance of the first electrode 50 to the light generated in the light-emitting layer 34. The second electrode 60 is transparent to the light generated in the light-emitting layer 34, for example. The thickness of the second electrode 60 is, for example, not less than 100 nm and not more than 500 nm, preferably not less than 250 nm and not more than 350 nm. If the thickness of the second electrode 60 is not less than 100 nm, the resistance can be reduced. If the thickness of the second electrode 60 is not more than 500 nm, the transmittance to the light generated in the light-emitting layer 34 can be increased. The material of the second electrode 60 is, for example, ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide).

[0064] 1.3. Effects

[0065] The light emitting device 100 includes: a laminate 20 provided on a substrate 10 and having a light emitting layer 34; a first electrode 50 in contact with the laminate 20 on the side of the laminate 20 opposite to the substrate 10 and injecting current into the light emitting layer 34; and a wiring layer 80 electrically connected to the first electrode 50 and having a light shielding property for light generated in the light emitting layer. The wiring layer 80 is provided with a first opening 82 through which light emitted from the laminate 20 passes, and the first opening 82 is located inside the outer edge 54 of the first electrode 50 in a plan view.

[0066] Therefore, in the light emitting device 100, the wiring layer 80 can block the light emitted from the portion (in the example shown in the figure, the first columnar portion 30a) overlapping with the outer edge 54 when the stack 20 is viewed from above. The portion of the stack 20 that overlaps with the outer edge 54 when viewed from above may be reduced, for example, due to overetching when the first electrode 50 is formed. Therefore, the light emitted from the portion that overlaps with the outer edge 54 when the stack 20 is viewed from above may have a wavelength shift or a reduction in the light emission intensity. In the light emitting device 100, by blocking such light with the wiring layer 80, the light emitted from the light emitting device 100 can be regulated by the first opening 82, thereby reducing the possibility of wavelength deviation and reduction in light emission intensity.

[0067] In the light emitting device 100, the stacked body 20 has a plurality of columnar portions 30, each of which has a first semiconductor layer 32 of a first conductivity type, a second semiconductor layer 36 of a second conductivity type different from the first conductivity type, and a light emitting layer 34 provided between the first semiconductor layer 32 and the second semiconductor layer 36. Therefore, in the light emitting device 100, the strain inside the light emitting layer 34 can be reduced compared with a case where the stacked body has a film-shaped light emitting layer instead of a plurality of columnar portions.

[0068] In the light emitting device 100, the first columnar portion 30a among the plurality of columnar portions 30 overlaps with the outer edge 54 of the first electrode 50 in a plan view. In the light emitting device 100, for example, even if the first columnar portion 30a is reduced due to overetching when the first electrode 50 is formed, the wiring layer 80 can block light emitted from the first columnar portion 30a.

[0069] In the light emitting device 100, the second electrode 60 is provided on the first electrode 50, the wiring layer 80 is electrically connected to the first electrode 50 via the second electrode 60, the resistivity of the first electrode 50 is lower than the resistivity of the second electrode 60, and the transmittance of the second electrode 60 to the light generated in the light emitting layer 34 is higher than the transmittance of the first electrode 50 to the light generated in the light emitting layer 34. Therefore, in the light emitting device 100, the contact resistance between the electrode structure composed of the first electrode 50 and the second electrode 60 and the laminate 20 can be reduced, and the transmittance of the electrode structure to the light generated in the light emitting layer 34 can be improved.

[0070] 2. Method for manufacturing a light-emitting device

[0071] Next, a method for manufacturing the light emitting device 100 according to the present embodiment will be described with reference to the drawings. Figures 4 to 6 It is a cross-sectional view schematically showing the manufacturing process of the light emitting device 100 of this embodiment.

[0072] like Figure 4 As shown, the buffer layer 22 is epitaxially grown on the substrate 10. Examples of epitaxial growth methods include MOCVD (Metal Organic Chemical Vapor Deposition) and MBE (Molecular Beam Epitaxy).

[0073] Next, a mask layer (not shown) is formed on the buffer layer 22. The mask layer is formed by, for example, electron beam deposition or sputtering.

[0074] Next, using the mask layer as a mask, the first semiconductor layer 32, the light emitting layer 34, and the second semiconductor layer 36 are epitaxially grown in sequence on the buffer layer 22. Examples of epitaxial growth methods include MOCVD and MBE. Through this process, a stacked body 20 having a plurality of columnar portions 30 can be formed.

[0075] like Figure 5 As shown, a first electrode 50 is formed on the stacked body 20. The first electrode 50 is formed, for example, by a CVD (Chemical Vapor Deposition) method or a sputtering method. Next, a resist layer 90 of a predetermined shape is formed on the first electrode 50. The resist layer 90 is formed by a photolithography method. Next, the first electrode 50 not covered by the resist layer 90 is etched using the resist layer 90 as a mask. The etching in this process is, for example, dry etching. In this process, in order to completely remove the first electrode 50 not covered by the resist layer 90, over-etching is performed. Therefore, a portion of the columnar portion 30 not covered by the resist layer 90 is etched.

[0076] like Figure 6 As shown, after removing the resist layer 90, the insulating layer 40 is formed to cover the laminate 20 and the first electrode 50. The insulating layer 40 is formed by, for example, CVD or spin coating. Next, the insulating layer 40 is patterned to form the second opening 42. The patterning is performed by, for example, photolithography and etching.

[0077] like Figure 1 As shown, the second electrode 60 is formed on the first electrode 50 and the insulating layer 40. The second electrode 60 is formed by, for example, a CVD method or a sputtering method.

[0078] Next, a wiring layer 80 is formed on the second electrode 60 and the insulating layer 40. The wiring layer 80 is formed by, for example, CVD or sputtering. Next, the wiring layer 80 is patterned to form the first opening 82. The patterning is performed by, for example, photolithography and etching.

[0079] Next, the third electrode 70 is formed on the buffer layer 22. The third electrode 70 is formed by, for example, CVD or sputtering. The order of forming the second electrode 60 and the third electrode 70 is not particularly limited. The order of forming the third electrode 70 and the wiring layer 80 is not particularly limited.

[0080] Through the above steps, the light emitting device 100 can be manufactured.

[0081] In addition, in the above, an example of forming the first electrode 50 by photolithography and etching is described, but the first electrode 50 may also be formed by a lift-off method. When the first electrode 50 is formed by the lift-off method, there is a possibility that the thickness near the outer edge 54 of the first electrode 50 becomes smaller. Therefore, even in the case where the first electrode 50 is formed by the lift-off method, light emitted from the portion overlapping the outer edge 54 when viewed from above of the stacked body 20 is preferably blocked by the wiring layer 80.

[0082] 3. Modifications of Light Emitting Device

[0083] Next, a light emitting device according to a modified example of the present embodiment will be described with reference to the drawings. Figure 7 2 is a cross-sectional view schematically showing a light emitting device 200 according to a modification of the present embodiment. Figure 8 2 is a top view schematically showing a light emitting device 200 according to a modified example of the present embodiment. Figure 7 yes Figure 8 In addition, for convenience, Figure 8 The second electrode 60 is omitted in the figure.

[0084] Hereinafter, in the light emitting device 200 according to the modification of the present embodiment, components having the same functions as those of the components of the light emitting device 100 according to the present embodiment described above are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0085] In the above-mentioned light emitting device 100, Figure 1 As shown in FIG. 4 , the wiring layer 80 is not provided in the second opening 42. In contrast, in the light emitting device 200, as shown in FIG. Figure 7 As shown, the wiring layer 80 is disposed in the second opening 42 .

[0086] In the light emitting device 200, the wiring layer 80 is provided on the side surface 44 of the insulating layer 40 via the second electrode 60. Figure 8 As shown, in a plan view, the area of ​​the first opening 82 is smaller than the area of ​​the second opening 42 , and the first opening 82 completely overlaps with the second opening 42 .

[0087] The light emitting device 200 includes an insulating layer 40 covering the laminate 20, a second opening 42 is provided in the insulating layer 40, the second opening 42 is provided inside the outer edge 54 of the first electrode 50 in a plan view, the second electrode 60 is provided on the side surface 44 of the insulating layer 40 defining the second opening 42, and the wiring layer 80 is provided on the side surface 44 via the second electrode 60, and the resistivity of the wiring layer 80 is lower than the resistivity of the second electrode 60. Therefore, in the light emitting device 200, the distance between the wiring layer 80 having a low resistivity and the first electrode 50 can be reduced compared to the case where the wiring layer is not provided on the side surface of the insulating layer via the second electrode. As a result, current can be efficiently injected into the light emitting layer 34.

[0088] 4. Projector

[0089] Next, a projector according to the present embodiment will be described with reference to the drawings. Fig. 9 1 is a diagram schematically showing a projector 800 according to this embodiment.

[0090] The projector 800 includes, for example, a light emitting device 100 as a light source.

[0091] The projector 800 includes a housing (not shown) and a red light source 100R, a green light source 100G, and a blue light source 100B, which are provided in the housing and emit red light, green light, and blue light, respectively. Fig. 9 In FIG. 1 , the red light source 100R, the green light source 100G, and the blue light source 100B are simplified.

[0092] The projector 800 further includes a first optical element 802R, a second optical element 802G, a third optical element 802B, a first light modulator 804R, a second light modulator 804G, a third light modulator 804B, and a projection device 808 in a housing. The first light modulator 804R, the second light modulator 804G, and the third light modulator 804B are, for example, transmissive liquid crystal light valves. The projection device 808 is, for example, a projection lens.

[0093] The light emitted from the red light source 100R enters the first optical element 802R. The light emitted from the red light source 100R is condensed by the first optical element 802R. The first optical element 802R may also have functions other than condensing light. The same is true for the second optical element 802G and the third optical element 802B described later.

[0094] The light focused by the first optical element 802R is incident on the first light modulator 804R. The first light modulator 804R modulates the incident light according to the image information. Then, the projection device 808 magnifies the image formed by the first light modulator 804R and projects it onto the screen 810.

[0095] The light emitted from the green light source 100G enters the second optical element 802G. The light emitted from the green light source 100G is condensed by the second optical element 802G.

[0096] The light focused by the second optical element 802G is incident on the second light modulator 804G. The second light modulator 804G modulates the incident light according to the image information. Then, the projection device 808 magnifies the image formed by the second light modulator 804G and projects it onto the screen 810.

[0097] The light emitted from the blue light source 100B enters the third optical element 802B. The light emitted from the blue light source 100B is condensed by the third optical element 802B.

[0098] The light focused by the third optical element 802B is incident on the third light modulator 804B. The third light modulator 804B modulates the incident light according to the image information. Then, the projection device 808 magnifies the image formed by the third light modulator 804B and projects it onto the screen 810.

[0099] Furthermore, the projector 800 can include a cross dichroic prism 806 that combines the light emitted from the first light modulator 804R, the second light modulator 804G, and the third light modulator 804B and guides the combined light to the projection device 808 .

[0100] The three color lights modulated by the first light modulator 804R, the second light modulator 804G, and the third light modulator 804B are incident on the cross dichroic prism 806. The cross dichroic prism 806 is formed by bonding four right-angle prisms, and a dielectric multilayer film reflecting red light and a dielectric multilayer film reflecting blue light are arranged on its inner surface. The three color lights are synthesized by these dielectric multilayer films to form light showing a color image. Then, the synthesized light is projected onto the screen 810 by the projection device 808 to display the enlarged image.

[0101] In addition, the red light source 100R, the green light source 100G, and the blue light source 100B can also directly form an image without using the first light modulator 804R, the second light modulator 804G, and the third light modulator 804B by using the light emitting device 100 as a pixel of the image and controlling it according to the image information. Furthermore, the projection device 808 can also enlarge the image formed by the red light source 100R, the green light source 100G, and the blue light source 100B and project it onto the screen 810.

[0102] In the above example, a transmissive liquid crystal light valve is used as the light modulator, but a light valve other than liquid crystal may be used, and a reflective light valve may be used. Examples of such light valves include reflective liquid crystal light valves and digital micro mirror devices. The structure of the projection device may be appropriately changed according to the type of light valve used.

[0103] In addition, the light source can also be applied to a light source device of a scanning type image display device, which has a scanning unit that is an image forming device that displays an image of a desired size on a display surface by scanning light from a light source on a screen.

[0104] 5. Display

[0105] Next, a display according to the present embodiment will be described with reference to the drawings. Fig.10 It is a plan view schematically showing a display 900 according to this embodiment. Fig.11 is a cross-sectional view schematically showing a display 900 according to this embodiment. Fig.10 In FIG. 1 , for convenience, an X-axis and a Y-axis are illustrated as two axes that are orthogonal to each other.

[0106] The display 900 has, for example, a light emitting device 100 as a light source.

[0107] The display 900 is a display device for displaying images. The images include images that display only text information. The display 900 is a self-luminous display. Fig.10 as well as Fig.11 As shown, the display 900 has a circuit substrate 910 , a lens array 920 , and a heat sink 930 .

[0108] A driving circuit for driving the light emitting device 100 is mounted on the circuit substrate 910. The driving circuit is, for example, a circuit including a CMOS (Complementary Metal Oxide Semiconductor). The driving circuit drives the light emitting device 100 based on input image information, for example. Although not shown in the figure, a substrate for protecting the light transmittance of the circuit substrate 910 is arranged on the circuit substrate 910.

[0109] The circuit substrate 910 includes a display area 912 , a data line driving circuit 914 , a scanning line driving circuit 916 , and a control circuit 918 .

[0110] The display area 912 is composed of a plurality of pixels P. In the example shown in the figure, the pixels P are arranged along the X-axis and the Y-axis.

[0111] Although not shown, a plurality of scan lines and a plurality of data lines are provided on the circuit substrate 910. For example, the scan lines extend along the X axis, and the data lines extend along the Y axis. The scan lines are connected to the scan line driving circuit 916. The data lines are connected to the data line driving circuit 914. Pixels P are provided corresponding to the intersections of the scan lines and the data lines.

[0112] One pixel P has, for example, one light emitting device 100, one lens 922, and a pixel circuit (not shown). The pixel circuit includes a switching transistor that functions as a switch of the pixel P. The switching transistor has a gate connected to a scanning line and one of a source or a drain connected to a data line.

[0113] The data line driving circuit 914 and the scanning line driving circuit 916 are circuits for controlling driving of the light emitting device 100 constituting the pixel P. The control circuit 918 controls display of an image.

[0114] The image data is supplied from the upper circuit to the control circuit 918. The control circuit 918 supplies various signals based on the image data to the data line driving circuit 914 and the scanning line driving circuit 916.

[0115] When the scan line driving circuit 916 selects a scan line by activating a scan signal, the switch transistor of the selected pixel P is turned on. At this time, the data line driving circuit 914 supplies a data signal from the data line to the selected pixel P, whereby the light emitting device 100 of the selected pixel P emits light according to the data signal.

[0116] The lens array 920 includes a plurality of lenses 922 . For example, one lens 922 is provided for one light emitting device 100 . Light emitted from the light emitting device 100 enters one lens 922 .

[0117] The heat sink 930 is in contact with the circuit board 910 . The heat sink 930 is made of metal such as copper or aluminum. The heat sink 930 dissipates heat generated by the light emitting device 100 .

[0118] The light emitting device according to the above-mentioned embodiment can also be used for purposes other than projectors and displays, such as indoor and outdoor lighting, laser printers, scanners, vehicle lights, light-using sensor equipment, communication equipment, and the like.

[0119] The above-mentioned embodiment and modification examples are merely examples, and the present invention is not limited thereto. For example, the embodiments and modification examples may be appropriately combined.

[0120] The present invention includes structures that are substantially the same as the structures described in the embodiments, such as structures with the same functions, methods and results, or structures with the same purposes and effects. In addition, the present invention includes structures that replace non-essential parts of the structures described in the embodiments. In addition, the present invention includes structures that can play the same role and effect as the structures described in the embodiments or structures that achieve the same purpose. In addition, the present invention includes structures that add known technologies to the structures described in the embodiments.

[0121] The following contents are derived from the above-mentioned embodiment and modification examples.

[0122] One mode of a light-emitting device comprises: a substrate; a stacked body, which is arranged on the substrate and has a light-emitting layer; a first electrode, which is in contact with the stacked body on the side of the stacked body opposite to the substrate and injects current into the light-emitting layer; a wiring layer, which is electrically connected to the first electrode and has a light-shielding property for light generated in the light-emitting layer, and a first opening portion is provided in the wiring layer for light emitted from the stacked body to pass through, and the first opening portion is located on the inner side of the outer edge of the first electrode when viewed from above.

[0123] According to this light emitting device, it is possible to block light emitted from a portion of the stacked body that overlaps with the outer edge of the first electrode in a plan view.

[0124] In one embodiment of the light-emitting device, the stack may have a plurality of columnar portions, each of the plurality of columnar portions having a first semiconductor layer of a first conductivity type, a second semiconductor layer of a second conductivity type different from the first conductivity type, and the light-emitting layer arranged between the first semiconductor layer and the second semiconductor layer.

[0125] According to this light-emitting device, the strain inside the light-emitting layer can be reduced.

[0126] In one aspect of the light emitting device, a first columnar portion among the plurality of columnar portions may overlap with the outer edge of the first electrode in a plan view.

[0127] According to this light emitting device, light emitted from the first columnar portion can be shielded by the wiring layer.

[0128] In one embodiment of the light-emitting device, there may be a second electrode arranged on the first electrode, the wiring layer is electrically connected to the first electrode via the second electrode, the resistivity of the first electrode is lower than the resistivity of the second electrode, and the transmittance of the second electrode to the light generated in the light-emitting layer is higher than the transmittance of the first electrode to the light generated in the light-emitting layer.

[0129] According to this light-emitting device, the contact resistance between the electrode structure including the first electrode and the second electrode and the stacked body can be reduced, and the transmittance of the electrode structure to light generated in the light-emitting layer can be increased.

[0130] In one embodiment of the light-emitting device, an insulating layer covering the stacked body may be provided, a second opening portion is provided in the insulating layer, the second opening portion is provided on the inner side of the outer edge of the first electrode when viewed from above, the second electrode is provided on the side surface of the insulating layer that specifies the second opening portion, the wiring layer is provided on the side surface via the second electrode, and the resistivity of the wiring layer is lower than the resistivity of the second electrode.

[0131] According to this light-emitting device, the distance between the wiring layer and the first electrode can be reduced, thereby enabling current to be efficiently injected into the light-emitting layer.

[0132] One embodiment of a projector includes one embodiment of the light emitting device.

[0133] One embodiment of a display includes one embodiment of the light emitting device.

Claims

1. A light emitting device, comprising: substrate; A laminated body, which is disposed on the substrate and has a light-emitting layer; A first electrode, which contacts the stacked body on a side of the stacked body opposite to the substrate and injects current into the light-emitting layer; as well as a wiring layer electrically connected to the first electrode and having a light shielding property for light generated in the light emitting layer, The wiring layer is provided with a first opening portion through which light emitted from the laminate passes. The first opening is located inside the outer edge of the first electrode in a plan view. The light emitting device comprises a second electrode disposed on the first electrode, The wiring layer is electrically connected to the first electrode via the second electrode, The resistivity of the first electrode is lower than the resistivity of the second electrode, The second electrode has a higher transmittance to light generated in the light-emitting layer than the first electrode has a transmittance to light generated in the light-emitting layer.

2. The light emitting device according to claim 1, wherein: The stacked body has a plurality of columnar portions, Each of the plurality of columnar portions has: a first semiconductor layer of a first conductivity type; a second semiconductor layer of a second conductivity type different from the first conductivity type; as well as The light emitting layer is disposed between the first semiconductor layer and the second semiconductor layer.

3. The light emitting device according to claim 2, wherein: A first columnar portion among the plurality of columnar portions overlaps with the outer edge of the first electrode in a plan view.

4. The light emitting device according to claim 1, wherein: The light emitting device includes an insulating layer covering the laminated body. A second opening is provided in the insulating layer, The second opening is provided inside the outer edge of the first electrode in a plan view, The second electrode is provided on a side surface of the insulating layer defining the second opening. The wiring layer is provided on the side surface via the second electrode. The wiring layer has a resistivity lower than that of the second electrode. 5 . A projector comprising the light emitting device according to claim 1 . 6 . A display comprising the light-emitting device according to claim 1 .

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