Light-emitting device and image display device

Abstract

A light-emitting device according to an embodiment of the present disclosure comprises a first electroconductive layer, a second electroconductive layer, a light-emitting layer provided between the first electroconductive layer and the second electroconductive layer, and a light constricting structure formed on at least one of the first electroconductive layer and the second electroconductive layer.

Description

Light-emitting device and image display device

[0001] The present disclosure relates to a light-emitting device and an image display device including the same.

[0002] For example, Patent Document 1 discloses a light-emitting device in which one or more light-collecting structures are provided on the light-emitting surface of the second compound semiconductor layer, and a current-confining structure is provided in the first compound semiconductor layer or the second compound semiconductor layer, thereby improving the light extraction efficiency.

[0003] International Publication No. 2023 / 032300

[0004] Meanwhile, in micro-sized displays, there is a demand for improved external quantum efficiency.

[0005] It is desirable to provide a light emitting device and an image display device that can improve the external quantum efficiency.

[0006] A light-emitting device according to one embodiment of the present disclosure includes a first conductive type layer, a second conductive type layer, a light-emitting layer provided between the first conductive type layer and the second conductive type layer, and a light confinement structure formed in at least one of the first conductive type layer and the second conductive type layer.

[0007] An image display device according to an embodiment of the present disclosure includes the light-emitting device according to the embodiment of the present disclosure as a light-emitting device.

[0008] In a light-emitting device and an image display device according to an embodiment of the present disclosure, a first conductivity-type layer, a light-emitting layer, and a second conductivity-type layer are stacked in this order, and at least one of the first conductivity-type layer and the second conductivity-type layer is provided with a light constriction structure, thereby reducing the spread of light in an in-plane direction perpendicular to the stacking direction of the layers without obstructing the optical path of light emitted from the light-emitting layer.

[0009] FIG. 1 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device according to a first embodiment of the present disclosure. FIG. 2 is a schematic diagram illustrating an example of a planar configuration of the light-emitting device shown in FIG. 1. FIG. 3 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device corresponding to line II-II' shown in FIG. 2. FIG. 4 is an exploded perspective view of the light-emitting device shown in FIG. 1. FIG. 5A is a schematic cross-sectional view illustrating a method for manufacturing the light-emitting device shown in FIG. 1. FIG. 5B is a schematic cross-sectional view illustrating a step subsequent to FIG. 5A. FIG. 5C is a schematic cross-sectional view illustrating a step subsequent to FIG. 5B. FIG. 5D is a schematic cross-sectional view illustrating a step subsequent to FIG. 5C. FIG. 5E is a schematic cross-sectional view illustrating a step subsequent to FIG. 5D. FIG. 5F is a schematic cross-sectional view illustrating a step subsequent to FIG. 5E. FIG. 5G is a schematic cross-sectional view illustrating a step subsequent to FIG. 5F. FIG. 6 is a schematic cross-sectional view illustrating an example of a cross-sectional configuration of a light-emitting device according to a first modification of the present disclosure. FIG. 7 is a schematic cross-sectional view illustrating an example of a planar configuration of the light-emitting device shown in FIG. 6. FIG. 8 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device corresponding to line IV-IV′ shown in FIG. 7 . FIG. 9 is a schematic cross-sectional view illustrating an example of a configuration of a light-emitting device according to Modification 2 of the present disclosure. FIG. 10 is a schematic cross-sectional view illustrating an example of a planar configuration of the light-emitting device shown in FIG. 9 . FIG. 11 is a schematic cross-sectional view illustrating an example of a configuration of a light-emitting device according to Modification 3 of the present disclosure. FIG. 12 is a schematic cross-sectional view illustrating an example of a configuration of a light-emitting device according to Modification 4 of the present disclosure. FIG. 13 is a schematic cross-sectional view illustrating an example of a planar configuration of the light-emitting device shown in FIG. 12 . FIG. 14 is a schematic cross-sectional view illustrating an example of a configuration of a light-emitting device according to Modification 5 of the present disclosure. FIG. 15 is a schematic cross-sectional view illustrating an example of a configuration of a light-emitting device according to Modification 6 of the present disclosure. FIG. 16 is a schematic cross-sectional view illustrating an example of a configuration of a light-emitting device according to Modification 7 of the present disclosure. FIG. 17 is a schematic cross-sectional view illustrating an example of a configuration of a light-emitting device according to Modification 8 of the present disclosure. FIG. 18 is a schematic cross-sectional view illustrating another example of the configuration of a light-emitting device according to Modification 8 of the present disclosure. Fig. 19 is a cross-sectional view schematically illustrating another example of the configuration of a light-emitting device according to Modification 8 of the present disclosure. Fig. 20 is a cross-sectional view schematically illustrating another example of the configuration of a light-emitting device according to Modification 8 of the present disclosure. Fig. 21 is a cross-sectional view schematically illustrating another example of the configuration of a light-emitting device according to Modification 8 of the present disclosure. Fig. 22 is a cross-sectional view schematically illustrating another example of the configuration of a light-emitting device according to Modification 8 of the present disclosure.FIG. 23 is a cross-sectional schematic diagram illustrating another example of the configuration of a light-emitting device according to Modification 8 of the present disclosure. FIG. 24 is a cross-sectional schematic diagram illustrating an example of the configuration of a light-emitting device according to Modification 9 of the present disclosure. FIG. 25 is a plan view schematic diagram illustrating an example of the layout of the light-emitting regions of each light-emitting unit shown in FIG. 24. FIG. 26 is a cross-sectional schematic diagram illustrating another example of the configuration of a light-emitting device according to Modification 9 of the present disclosure. FIG. 27A is a plan view schematic diagram illustrating an example of the layout of the light-emitting regions of each light-emitting unit shown in FIG. 26. FIG. 27B is a plan view schematic diagram illustrating another example of the layout of the light-emitting regions of each light-emitting unit shown in FIG. 26. FIG. 28 is a cross-sectional schematic diagram illustrating another example of the configuration of a light-emitting device according to Modification 9 of the present disclosure. FIG. 29 is a cross-sectional schematic diagram illustrating another example of the configuration of a light-emitting device according to Modification 9 of the present disclosure. FIG. 30 is a cross-sectional schematic diagram illustrating an example of the configuration of a light-emitting device according to Modification 10 of the present disclosure. FIG. 31A is a front view illustrating an example of the appearance of a digital still camera as an application example of the present disclosure. FIG. 31B is a rear view illustrating an example of the appearance of the digital still camera shown in FIG. 31A. FIG. 32A is a perspective view illustrating the appearance of an example of a head-mounted display as an application example of the present disclosure. FIG. 32B is a perspective view illustrating the appearance of another example of a head-mounted display as an application example of the present disclosure. FIG. 33 is a perspective view illustrating an example of the appearance of a television set as an application example of the present disclosure. FIG. 34 is a schematic view illustrating an example of a cross-sectional configuration of a light-emitting device according to a second embodiment of the present disclosure. FIG. 35A is a schematic view illustrating an example of a planar configuration of the light-emitting device shown in FIG. 34. FIG. 35B is a schematic view illustrating another example of the planar configuration of the light-emitting device shown in FIG. 34. FIG. 36A is a schematic cross-sectional view illustrating another example of the shape of the microlens shown in FIG. 34. FIG. 36B is a schematic cross-sectional view illustrating another example of the shape of the microlens shown in FIG. 34. FIG. 36C is a schematic cross-sectional view illustrating another example of the shape of the microlens shown in FIG. 34. FIG. 36D is a schematic cross-sectional view illustrating another example of the shape of the microlens shown in FIG. 34. FIG. 36E is a schematic cross-sectional view illustrating another example of the shape of the microlens shown in FIG. 34. FIG. 37A is a schematic cross-sectional view illustrating a method for manufacturing the light-emitting device shown in FIG. 1. Fig. 37B is a schematic cross-sectional view showing a step subsequent to Fig. 37A. Fig. 37C is a schematic cross-sectional view showing a step subsequent to Fig. 37B.FIG. 37D is a schematic cross-sectional view showing a step subsequent to FIG. 37C. FIG. 37E is a schematic cross-sectional view showing a step subsequent to FIG. 37D. FIG. 37F is a schematic cross-sectional view showing a step subsequent to FIG. 37E. FIG. 37G is a schematic cross-sectional view showing a step subsequent to FIG. 37F. FIG. 37H is a schematic cross-sectional view showing a step subsequent to FIG. 37G. FIG. 37I is a schematic cross-sectional view showing a step subsequent to FIG. 37H. FIG. 38 is a schematic view showing an example of a cross-sectional configuration of a light-emitting device according to Modification 11 of the present disclosure. FIG. 39 is a schematic view showing an example of a cross-sectional configuration of a light-emitting device according to Modification 12 of the present disclosure. FIG. 40 is a schematic view showing an example of a cross-sectional configuration of a light-emitting device according to Modification 13 of the present disclosure. FIG. 41 is a schematic view showing an example of a cross-sectional configuration of a light-emitting device according to Modification 14 of the present disclosure.

[0010] Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the drawings. The following description is a specific example of the present disclosure, and the present disclosure is not limited to the following aspect. Furthermore, the present disclosure is not limited to the arrangement, dimensions, dimensional ratios, etc. of each component shown in each drawing. The description will be given in the following order. 1. First embodiment (example of a light emitting device in which a light confinement structure is provided in the second cladding layer on the light extraction surface side) 2. Modifications 2-1. Modification 1 (another example of the configuration of a light emitting device) 2-2. Modification 2 (another example of the configuration of a light emitting device) 2-3. Modification 3 (another example of the configuration of a light emitting device) 2-4. Modification 4 (another example of the configuration of a light emitting device) 2-5. Modification 5 (another example of the configuration of a light emitting device) 2-6. Modification 6 (another example of the configuration of a light emitting device) 2-7. Modification 7 (another example of the configuration of a light emitting device) 2-8. Modification 8 (another example of the configuration of a light emitting device) 2-9. Modification 9 (another example of the configuration of a light emitting device) 2-10. Modification 10 (another example of the configuration of the light-emitting device) 3. Second embodiment (an example of a light-emitting device having a condenser lens layer made of an inorganic material on the light extraction surface side, and in which the center of the groove provided between pixels in the condenser lens layer coincides with the center of the light confinement structure) 4. Modifications 4-1. Modification 11 (another example of the configuration of the light-emitting device) 4-2. Modification 12 (another example of the configuration of the light-emitting device) 4-3. Modification 13 (another example of the configuration of the light-emitting device) 4-4. Modification 14 (another example of the configuration of the light-emitting device) 4-5. Other modifications 5. Application examples

[0011] 1. First Embodiment FIG. 1 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device (light-emitting device 1) according to a first embodiment of the present disclosure. FIG. 2 is a schematic diagram illustrating an example of a planar configuration of the light-emitting device 1 illustrated in FIG. 1. FIG. 1 illustrates a cross section corresponding to line II' illustrated in FIG. 2. FIG. 3 is a schematic diagram illustrating an example of a cross-sectional configuration of the light-emitting device 1 corresponding to line II-II' illustrated in FIG. 2. The light-emitting device 1 is suitably applicable to image display devices known as LED displays (for example, the electronic viewfinder 1124 of a digital still camera 1120, see FIG. 32B ).

[0012] The light emitting device 1 is formed by laminating, in this order, a first cladding layer 11, a light emitting layer 12, and a second cladding layer 13. The second cladding layer 13 has a light constriction structure 130 formed therein.

[0013] Here, the first cladding layer corresponds to a specific example of a "first conductivity type layer" in an embodiment of the present disclosure. The light emitting layer 12 corresponds to a specific example of a "light emitting layer" in an embodiment of the present disclosure. The second cladding layer 13 corresponds to a specific example of a "second conductivity type layer" in an embodiment of the present disclosure. The light constriction structure 130 corresponds to a specific example of a "light constriction structure" in an embodiment of the present disclosure.

[0014] [Configuration of the Light-Emitting Device] The light-emitting device 1 includes a first cladding layer 11, a light-emitting layer 12, and a second cladding layer 13 stacked in this order. The light-emitting device 1 includes a drive substrate 20 disposed on the first cladding layer 11 side, and a light-extraction side S1 on the second cladding layer 13 side. The first cladding layer 11 has a pair of opposing surfaces (surfaces 11S1 and 11S2), with surface 11S1 facing the light-emitting layer 12. The second cladding layer 13 has a pair of opposing surfaces (surfaces 13S1 and 13S2), with surface 13S1 facing the light-emitting layer 12 and surface 13S2 serving as a light-extraction surface. As described above, the second cladding layer 13 includes a light-confining structure 130. A first electrode 14 and a second electrode 15 are electrically connected to the first cladding layer 11 and the second cladding layer 13, respectively. The first electrode 14 is provided on the surface 11S2 side of the first cladding layer 11 and is electrically connected to the first cladding layer 11. An opening 16 is formed in the first cladding layer 11, penetrating the first cladding layer 11 and the light-emitting layer 12 to reach the second cladding layer 13. The second electrode 15 is electrically connected to the second cladding layer 13 from the first cladding layer 11 side through the opening 16. An interlayer insulating layer 21 is provided between the first cladding layer 11 and the drive substrate 20. The interlayer insulating layer 21 fills the opening 16 and includes the first electrode 14, the second electrode 15, and a wiring layer 17 within the layer. A plurality of contacts 22 are further embedded within the interlayer insulating layer 21, and the first cladding layer 11 and the second cladding layer 13 are electrically connected to the drive substrate 20 via the contacts 22.

[0015] The first cladding layer 11 is for supplying active carriers to the light emitting layer 12 by doping or the like. The first cladding layer 11 is formed of, for example, a p-type GaN-based compound semiconductor material, and supplies holes as active carriers to the light emitting layer 12. The first cladding layer 11 may also be formed of, for example, a phosphorus (P)-based compound semiconductor material such as p-type AlGaInP or GaInP, or p-type AlGaAs.

[0016] The light-emitting layer 12 emits and amplifies spontaneously emitted light, and generates stimulated emission light through luminescent recombination of holes and electrons injected from the first electrode 14 and the second electrode 15. The light-emitting layer 12 has a multiple quantum well (MQW) structure in which multiple well layers 121 and barrier layers 122 are alternately stacked, as shown in FIG.

[0017] The well layer 121 is a double heterojunction layer sandwiched between barrier layers 122, and by confining carriers within the layer, highly efficient radiative recombination is achieved. The barrier layer 122 is a heterojunction layer formed to confine carriers in the well layer 121, and is a layer with quantum barrier properties. The barrier layer 122 is formed to be thicker than the well layer 121. The light-emitting layer 12 (specifically, the well layer 121) has a light-emitting region 12X within the layer. The well layer 121 is formed of, for example, InGaN, and the barrier layer 122 is formed of, for example, GaN. Alternatively, the well layer 121 may be formed of, for example, GaInP or GaAs, and the barrier layer 122 is formed of, for example, a phosphorus (P)-based compound semiconductor material such as AlGaInP or GaInP, or AlGaAs.

[0018] Similar to the first cladding layer 11, the second cladding layer 13 is intended to supply active carriers to the light emitting layer 12 by doping or the like. The second cladding layer 13 is formed of, for example, an n-type GaN-based compound semiconductor material, and supplies electrons as active carriers to the light emitting layer 12. The second cladding layer 13 may also be formed of, for example, a phosphorus (P)-based compound semiconductor material such as n-type AlGaInP or GaInP, or n-type AlGaAs.

[0019] The light confining structure 130 provides a confining effect to the current injected from the second electrode 15 without interfering with the optical path of the light emitted from the light-emitting layer 12. The light confining structure 130 is formed on the outer periphery of the light-emitting device 1 so as to surround the light-emitting region 12X, as shown in FIG. 2, for example. The light confining structure 130 has light-absorbing and insulating properties, and can be formed, for example, by ion-implanting impurities from the surface (e.g., surface 13S2) side of the second cladding layer 13. Alternatively, the light confining structure 130 may be formed by embedding a black matrix or the like in the second cladding layer 13.

[0020] 1 , the light constriction structure 130 may be formed from the second cladding layer 13 to a part of the light emitting layer 12. Alternatively, the light constriction structure 130 may be formed to penetrate the second cladding layer 13 and the light emitting layer 12 to the first cladding layer 11.

[0021] The first electrode 14 is in contact with the first cladding layer 11 and is electrically connected to the first cladding layer 11. In other words, the first electrode 14 is in ohmic contact with the first cladding layer 11. The first electrode 14 is, for example, a metal electrode, and is configured as, for example, a multilayer film (Ni / Au) of nickel (Ni) and gold (Au). Alternatively, the first electrode 14 may be formed using a transparent conductive material such as indium tin oxide (ITO).

[0022] The second electrode 15 is in contact with the second cladding layer 13 through an opening 16 that penetrates the first cladding layer 11 and the light-emitting layer 12 and reaches the second cladding layer 13, and is electrically connected to the second cladding layer 13. In other words, the second electrode 15 is in ohmic contact with the second cladding layer 13. Like the first electrode 14, the second electrode 15 is formed as a multilayer film (Ni / Au) of nickel (Ni) and gold (Au), for example. Alternatively, the first electrode 14 may be formed using a transparent conductive material such as indium tin oxide (ITO).

[0023] [Method of Manufacturing Light-Emitting Device] The light-emitting device 1 can be manufactured, for example, as follows: Figures 5A to 5G show an example of a manufacturing process for the light-emitting device 1.

[0024] 5A , the second cladding layer 13, the light-emitting layer 12, and the first cladding layer 11 are laminated in this order on a support substrate 30. The first cladding layer 11, the light-emitting layer 12, and the second cladding layer 13 can be formed by epitaxial crystal growth using a method such as metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE).

[0025] 5B , an opening 16 is formed that penetrates the first cladding layer 11 and the light-emitting layer 12 and reaches the second cladding layer 13. Subsequently, as shown in FIG. 5B , an insulating layer (interlayer insulating layer 21) is formed on the first cladding layer 11 and on the side and bottom surfaces of the opening 16, and then the interlayer insulating layer 21 formed on the bottom surface of the opening 16 is etched back to expose the second cladding layer 13.

[0026] 5C , an opening is formed at a predetermined position in interlayer insulating layer 21, and a conductive film is formed on interlayer insulating layer 21 and on the side and bottom surfaces of opening 16H, and then the conductive film is processed by, for example, photolithography, thereby forming first electrode 14, second electrode 15, wiring layer 17, and plug 18 connecting second electrode 15 and wiring layer 17.

[0027] 5D, an interlayer insulating layer 21 is further formed to fill the opening 16, and the drive substrate 20 is attached via the contact 22. Next, as shown in FIG. 5E, the support substrate 30 is peeled off.

[0028] Next, as shown in Fig. 5F, a resist film 201 is formed in a predetermined pattern on the surface 13S2 of the second cladding layer 13. Next, as shown in Fig. 5F, the impurity concentration of the second cladding layer 13 exposed from the resist film 201 is controlled by, for example, ion implantation to form the light confinement structure 130. Thereafter, as shown in Fig. 5G, the resist film 201 is removed, and the surface of the second cladding layer 13 is planarized by, for example, chemical mechanical polishing (CMP). This completes the light-emitting device 1 shown in Figs. 1 and 3.

[0029] [Functions and Effects] The light emitting device 1 of the present embodiment has a configuration in which the first cladding layer 11, the light emitting layer 12, and the second cladding layer 13 are stacked in this order, and the second cladding layer 13, which serves as the light extraction surface, is provided with a light constriction structure 130. This reduces the spread of light in an in-plane direction perpendicular to the stacking direction of the layers 11, 12, and 13, without interfering with the optical path of light emitted from the light emitting layer 12. This is described below.

[0030] 2. Description of the Related Art In recent years, high-definition image display devices using light-emitting devices having micro-sized light-emitting diodes (hereinafter referred to as micro-LEDs) using gallium nitride (GaN) as light sources have become widespread.

[0031] Micro-LEDs have the problem of rapidly decreasing external quantum efficiency as the device size decreases. This is because carriers are trapped in recombination centers that form at the end faces of the device when it is isolated by mesa processing, and many of the carriers are consumed as non-radiative recombinations and do not contribute to light emission. Therefore, in recent years, a method has been used to improve internal quantum efficiency by selectively placing electrodes directly below the active layer to concentrate current (current confinement) within the active layer and concentrate carriers in a specific region to emit light. Another method is to confine the current by implanting ions into the conductive layer to form a high-resistance region (current confinement region).

[0032] Ion implantation is a common technique in electronic devices, and it allows for highly precise and selective formation of current confinement regions using semiconductor processes. However, in micro-LEDs with current confinement regions, even though the active layer is not damaged, the external quantum efficiency still exhibits a device size dependency, and a shift in peak current density has been reported. Furthermore, it has been found that significant variations in light emission occur when the device size is around 1 μm.

[0033] This variation in light emission is thought to be due to the light absorption of the current confinement region. During ion implantation, accelerated ions injected into the conductive layer collide with atoms in the crystal, forming vacancies (crystal defects) and compounds with the ions. Because crystal defects hinder carrier movement, the ion-implanted region becomes highly resistive. At the same time, an intermediate potential due to the crystal defects and compounds with the ions is formed within the band gap. As a result, light emitted from the active layer is absorbed. Considering this light absorption, the decrease in external quantum efficiency in micro-LEDs with current confinement regions in the conductive layers sandwiching the active layer is justified.

[0034] In contrast to this, in the present embodiment, in the configuration in which the first cladding layer 11, the light-emitting layer 12, and the second cladding layer 13 are laminated in this order as described above, the light constriction structure 130 is provided in the second cladding layer 13, which serves as the light extraction surface, at a position that does not obstruct the optical path of light emitted from the light-emitting layer 12. This makes it possible to reduce the spread of light in the in-plane direction perpendicular to the lamination direction of the above layers 11, 12, and 13, without obstructing the optical path of the light emitted from the light-emitting layer 12.

[0035] As a result, the light emitting device 1 of this embodiment can improve the external quantum efficiency.

[0036] Next, a second embodiment of the present disclosure, modified examples 1 to 14, and application examples will be described. Note that components corresponding to those in the light emitting device 1 of the first embodiment are given the same reference numerals, and descriptions thereof will be omitted.

[0037] <2. Modifications> (2-1. Modification 1) FIG. 6 is a schematic diagram showing an example of a cross-sectional configuration of a light-emitting device (light-emitting device 1A) according to Modification 1 of the present disclosure. FIG. 7 is a schematic diagram showing an example of a planar configuration of the light-emitting device 1A shown in FIG. 6. FIG. 6 shows a cross section corresponding to line III-III' shown in FIG. 7. FIG. 8 is a schematic diagram showing an example of a cross-sectional configuration of the light-emitting device 1A corresponding to line IV-IV' shown in FIG. 7. As with the first embodiment, the light-emitting device 1A is suitably applicable to image display devices known as LED displays (for example, the electronic viewfinder 1124 of a digital still camera 1120).

[0038] In the first embodiment described above, an example was shown in which the light confining structure 130 is continuously formed to surround the light emitting region 12X, and an opening 16 is formed inside the light confining structure 130, through which the second cladding layer 13 and the second electrode 15 are electrically connected. However, this is not limiting. In the light emitting device 1A of this modification, a portion of the light confining structure 130 surrounding the light emitting region 12X is divided, and an opening 16 is formed at the position where the light confining structure 130 is divided. Except for this point, the light emitting device 1A has substantially the same configuration as the light emitting device 1 of the first embodiment described above.

[0039] Even with this configuration, the light emitting device 1A of this modification can achieve the same effects as the light emitting device 1 of the first embodiment.

[0040] (2-2. Modification 2) Fig. 9 is a schematic representation of an example of a cross-sectional configuration of a light-emitting device (light-emitting device 1B) according to Modification 2 of the present disclosure. Fig. 10 is a schematic representation of an example of a planar configuration of light-emitting device 1B shown in Fig. 9. Fig. 9 shows a cross section corresponding to line VV' shown in Fig. 10. Similar to the first embodiment described above, light-emitting device 1B is suitably applicable to image display devices known as LED displays (for example, electronic viewfinder 1124 of digital still camera 1120, etc.).

[0041] In the first embodiment, an example in which only one light-emitting region 12X is formed within the surface of the light-emitting layer 12 has been described, but the present invention is not limited to this. In the light-emitting device 1B of this modification, a plurality of light-emitting regions 12X are arranged within the surface of the light-emitting layer 12, for example, in a two-dimensional array. Except for this point, the light-emitting device 1B has substantially the same configuration as the light-emitting device 1 of the first embodiment.

[0042] The light emitting device 1B has a plurality of light emitting regions 12X arranged in a two-dimensional array, and each light emitting region 12X constitutes a display pixel P in the light emitting device 1B. In the light emitting device 1B, a light confining structure 130 is formed to surround each of the light emitting regions 12X in a planar view. In other words, for example, in the light emitting device 1B in which the light emitting regions 12X are arranged in a matrix, the light confining structure 130 is formed in a lattice shape to surround each of the light emitting regions 12X in a planar view. In the light emitting device 1B, a first electrode 14 is provided for each of the light emitting regions 12X. Furthermore, in the light emitting device 1B, an opening 16 that penetrates the first cladding layer 11 and the light emitting layer 12 and reaches the second cladding layer 13 is formed for each of the light emitting regions 12X individually surrounded by the light confining structure 130. In other words, the second cladding layer 13 and the second electrode 15 are electrically connected for each display pixel P.

[0043] As described above, in the light emitting device 1B of this modification, a plurality of light emitting regions 12X are arranged in a two-dimensional array within the surface of the light emitting layer 12, and a light confinement structure 130 is formed to surround each of the plurality of light emitting regions 12X. Furthermore, an opening 16 is formed for each of the light emitting regions 12X individually surrounded by the light confinement structure 130, and the second cladding layer 13 and the second electrode 15 are electrically connected for each display pixel P. Even with this configuration, the light emitting device 1B of this modification can achieve the same effects as the light emitting device 1 of the first embodiment.

[0044] Additionally, in the light emitting device 1B in this modified example in which a plurality of light emitting regions 12X are arranged within the surface of the light emitting layer 12, for example, in a two-dimensional array, if a section including each light emitting region 12X separated by the light constriction structure 130 is regarded as a single element, stray light can be prevented from reaching adjacent elements, thereby enabling the contrast to be improved in an image display device including such a light emitting device 1B.

[0045] 11 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device (light-emitting device 1C) according to Modification 3 of the present disclosure. Similar to the first embodiment, light-emitting device 1C is suitable for use in image display devices known as LED displays (for example, electronic viewfinder 1124 of digital still camera 1120).

[0046] In the above-described second modification, an example was shown in which a plurality of light-emitting regions 12X arranged in a two-dimensional array are each individually surrounded by a light constriction structure 130 that extends from the surface 13S2 of the second cladding layer 13 to a part of the light-emitting layer 12, but the present invention is not limited to this. In the light-emitting device 1C of this modification, a plurality of light-emitting regions 12X arranged in a two-dimensional array are each individually surrounded by a light constriction structure 130A that extends from the surface 13S2 of the second cladding layer 13 toward the surface 13S2 and has a bottom within the second cladding layer 13. Except for this point, the light-emitting device 1C has substantially the same configuration as the light-emitting device 1 of the first embodiment.

[0047] In this way, in light emitting device 1C of this modification, a plurality of light emitting regions 12X arranged in a two-dimensional array are individually surrounded by light confining structures 130A that extend from surface 13S2 toward surface 13S2 of second cladding layer 13 and have their bottoms within second cladding layer 13. Even with this configuration, light emitting device 1C of this modification can achieve the same effects as light emitting device 1 of the first embodiment and light emitting device 1B of modification 2.

[0048] (2-4. Modification 4) Fig. 12 is a schematic diagram showing an example of a cross-sectional configuration of a light-emitting device (light-emitting device 1D) according to Modification 4 of the present disclosure. Fig. 13 is a schematic diagram showing an example of a planar configuration of light-emitting device 1D shown in Fig. 2. Fig. 12 shows a cross section corresponding to line VI-VI' shown in Fig. 13. As with the first embodiment, light-emitting device 1D is suitably applicable to image display devices known as LED displays (for example, electronic viewfinder 1124 of digital still camera 1120).

[0049] In the above-described second modification, the light-emitting regions 12X arranged in a two-dimensional array are each individually surrounded by a light confining structure 130, an opening 16 is formed for each light-emitting region 12X individually surrounded by the light confining structure 130, and the second cladding layer 13 and the second electrode 15 are electrically connected for each display pixel P. However, this is not limiting. The light-emitting device 1D of this modification has a pixel array section 100A in which a plurality of display pixels P, each including a light-emitting region 12X, are arranged in a two-dimensional array, and a peripheral section 100B provided on the periphery of the pixel array section 100A. In the light-emitting device 1D, the light-confining structures 130 individually surrounding the plurality of light-emitting regions 12X arranged in a two-dimensional array are divided at the intersections of adjacent display pixels P in the X-axis direction and the Y-axis direction. For example, one opening 16 is formed in the peripheral section 100B, penetrating the first cladding layer 11 and the light-emitting layer 12 to reach the second cladding layer 13. That is, in the light emitting device 1D, the second electrode 15 is provided, for example, in the outer peripheral portion 100B as a common electrode for a plurality of display pixels P. Except for this point, the light emitting device 1D has substantially the same configuration as the light emitting device 1 of the first embodiment described above.

[0050] Even with this configuration, the light emitting device 1D of this modified example can achieve the same effects as the light emitting device 1 of the first embodiment and the light emitting device 1B of the modified example 2.

[0051] In the above-described modified example 2, an opening 16 is formed in each light-emitting region 12X individually surrounded by the light constriction structure 130. In addition, in the above-described modified example 4, an example is shown in which the light constriction structure 130 is divided at the intersections of adjacent display pixels P in the X-axis direction and the Y-axis direction, openings 16 are formed in the outer periphery 100B, and second electrodes 15 are provided as common electrodes for the plurality of display pixels P, but the present invention is not limited to this. For example, modified examples 2 and 4 may be combined, and openings 16 may be formed at each divided position of the light constriction structure 130 divided at the intersections of adjacent display pixels P in the X-axis direction and the Y-axis direction, and second electrodes 15 may be provided in each opening 16.

[0052] 14 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device (light-emitting device 1E) according to Modification 5 of the present disclosure. Similar to the first embodiment, light-emitting device 1E is suitable for use in image display devices known as LED displays (for example, electronic viewfinder 1124 of digital still camera 1120).

[0053] The light confining structure 130 of the above-described modification 4 may be the light confining structure 130A that extends from the surface 13S2 of the second cladding layer 13 toward the surface 13S2 of the second cladding layer 13 and has a bottom portion within the second cladding layer 13, as in the above-described modification 3. Except for this point, the light emitting device 1E has substantially the same configuration as the light emitting device 1 of the above-described first embodiment.

[0054] Even with this configuration, the light emitting device 1E of this modified example can achieve the same effects as the light emitting device 1 of the first embodiment and the light emitting device 1B of the modified example 2.

[0055] In addition, when there is a gap between the light constriction structure 130A and the light-emitting layer 12, as in the light constriction structure 130A of this modified example, the second clad layer 13 of each display pixel P is connected by this gap, so the light constriction structure 130A does not necessarily have to be divided at the intersection of adjacent display pixels P in the X-axis direction and the Y-axis direction.

[0056] 15 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device (light-emitting device 1F) according to Modification 6 of the present disclosure. Similar to the first embodiment, the light-emitting device 1F is suitably applicable to image display devices known as LED displays (for example, the electronic viewfinder 1124 of a digital still camera 1120).

[0057] In the first embodiment described above, an example was shown in which second cladding layer 13 and second electrode 15 were electrically connected via opening 16 that penetrates first cladding layer 11 and light-emitting layer 12 and reaches second cladding layer 13, but this is not limiting. In light-emitting device 1E of this modification, second electrode 15A is provided on surface 13S2, which serves as the light extraction surface of second cladding layer 13. Except for this point, light-emitting device 1F has substantially the same configuration as light-emitting device 1 of the first embodiment described above.

[0058] The second electrode 15A is in contact with the second cladding layer 13 from the surface 13S2 side, which is the light extraction surface, and is electrically connected to the second cladding layer 13. In other words, the second electrode 15A is in ohmic contact with the second cladding layer 13. The second electrode 15A is formed using a transparent conductive material such as ITO.

[0059] 15 , the second electrode 15A is provided on a surface 13S2 serving as a light extraction surface of the second cladding layer 13, and extends through the pixel array section 100A as a common layer for a plurality of display pixels P. Furthermore, the second electrode 15A is extended to, for example, the outer peripheral section 100B, and is electrically connected to the electrode 15B provided in the opening 16 through an opening 13H formed in the outer peripheral section 100B and penetrating the second cladding layer 13.

[0060] In this way, in the light emitting device 1F of this modified example, the second electrode 15A is provided on the surface 13S2, which serves as the light extraction surface, of the second cladding layer 13. Even with this configuration, the light emitting device 1F of this modified example can achieve the same effects as the light emitting device 1 of the first embodiment and the light emitting device 1B of the modified example 2.

[0061] 16 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device (light-emitting device 1G) according to Modification 7 of the present disclosure. Similar to the first embodiment, the light-emitting device 1G is suitable for use in image display devices known as LED displays (for example, the electronic viewfinder 1124 of a digital still camera 1120).

[0062] The light emitting device 1G of this modification has a light collection structure formed on the surface 13S2, which serves as the light extraction surface, of the second cladding layer 13. The light collection structure is, for example, a convex lens 13L. Except for this point, the light emitting device 1G has substantially the same configuration as the light emitting device 1 of the first embodiment.

[0063] The lens 13L is disposed, for example, above the light-emitting device to increase the proportion of light incident at the capture angle of a lens (not shown) that captures light emitted from the light-emitting device. The lens 13L may have, for example, an outer diameter that is approximately the same as or smaller than the outer diameter of the display pixel. The lens 13L is made of the same material as the second cladding layer 13 and can be formed, for example, by etching the second cladding layer 13.

[0064] The light-condensing structure is not limited to the convex lens 13L, but may be any structure that has the effect of bending light, such as a surface relief, an inclined surface, or a nano-periodic structure.

[0065] In this way, in the light emitting device 1G of this modification, a light collection structure (e.g., lens 13L) is formed on the surface 13S2, which serves as the light extraction surface of the second cladding layer 13. This increases the proportion of light incident on the capture angle of the lens, which is disposed above the light emitting device and captures light emitted from the light emitting device. Therefore, in addition to the effects of the first embodiment and modification 2, it is possible to improve the light extraction efficiency.

[0066] (2-8. Modification 8) Fig. 17 is a schematic representation of an example cross-sectional configuration of a light-emitting device according to Modification 8 of the present disclosure (light-emitting device 1H). Figs. 18 to 23 are schematic representations of other examples of cross-sectional configurations of light-emitting devices according to Modification 8 of the present disclosure (light-emitting devices 1I to 1N). Similar to the first embodiment described above, light-emitting devices 1H to 1N are suitably applicable to image display devices known as LED displays (for example, electronic viewfinder 1124 of digital still camera 1120).

[0067] In the first embodiment, an example was shown in which the light confining structure 130 was provided only on the second cladding layer 13 side arranged on the light extraction side S1, but this is not limited to this. The light emitting device 1H of this modification is the light emitting device 1 of the first embodiment, except that a light confining structure 110 is further provided in the first cladding layer 11. The light emitting device 1I of this modification is the light emitting device 1B of Modification 2, except that a light confining structure 110 is provided in the first cladding layer 11. The light emitting device 1J of this modification is the light emitting device 1C of Modification 3, except that a light confining structure 110 is provided in the first cladding layer 11. The light emitting device 1K of this modification is the light emitting device 1D of Modification 4, except that a light confining structure 110 is provided in the first cladding layer 11. The light emitting device 1L of this modification is the light emitting device 1E of Modification 5, except that a light confining structure 110 is provided in the first cladding layer 11. The light emitting device 1M of this modification is obtained by providing an optical constriction structure 110 in the first cladding layer 11 of the light emitting device 1F of the above-described modification 6. The light emitting device 1N of this modification is obtained by providing an optical constriction structure 110 in the first cladding layer 11 of the light emitting device 1G of the above-described modification 7. Except for these points, the light emitting devices 1H, 1I to 1N have substantially the same configuration as the light emitting devices 1 of the above-described first embodiment and modifications 2 to 7.

[0068] The light confining structure 110 provides a confining effect to the current injected from the first electrode 14. Like the light confining structure 130, the light confining structure 110 is formed to surround the light emitting region 12X. Like the light confining structure 130, the light confining structure 110 has light absorption and insulating properties, and can be formed, for example, by ion-implanting impurities from the surface (e.g., surface 11S2) side of the first cladding layer 11. Alternatively, the light confining structure 110 may be formed by embedding a black matrix or the like in the first cladding layer 11.

[0069] In the light-emitting devices 1H to 1N of the present modified examples, the width W2 of the light constriction structure 130 is formed to be smaller than the width W1 of the light constriction structure 110. This is because, as described above, the light constriction structure 130 does not obstruct the optical path of the light emitted from the light-emitting layer 12. Specifically, in a configuration in which a plurality of display pixels P are arranged in a two-dimensional array, the light constriction structure 130 is preferably formed selectively at the boundary portion between adjacent display pixels P. This makes it possible to improve contrast without obstructing the optical path of the light emitted from the light-emitting layer 12.

[0070] As described above, in the light emitting devices 1H to 1N of the present modified examples, the light confinement structure 130 is provided in the second cladding layer 13 arranged on the light extraction side S1, and the light confinement structure 110 is provided in the first cladding layer 11 arranged on the opposite side from the light extraction side S1. This improves the efficiency of current injection from the first electrode 14 side to the light emitting layer 12. Therefore, it is possible to further improve the external quantum efficiency compared to the light emitting device 1 of the first embodiment described above.

[0071] (2-9. Modification 9) FIG. 24 is a schematic diagram showing an example of a cross-sectional configuration of a light-emitting device (light-emitting device 1O) according to Modification 9 of the present disclosure. FIG. 25 is a schematic diagram showing an example of a planar layout of the light-emitting regions of the light-emitting units 10R, 10G, and 10B of the light-emitting device 1O shown in FIG. 24. FIGS. 26, 28, and 29 are schematic diagrams showing other examples of cross-sectional configurations of light-emitting devices (light-emitting devices 1P to 9C) according to Modification 9 of the present disclosure. FIGS. 27A and 27B are schematic diagrams showing an example of a planar layout of the light-emitting regions of the light-emitting units 10R, 10G, and 10B of the light-emitting device 1P shown in FIG. 26. The light-emitting devices 1O, 9A to 9C, like the first embodiment, are suitable for use in image display devices known as LED displays (e.g., the electronic viewfinder 1124 of a digital still camera 1120).

[0072] The light emitting device 1O of this modification includes, for example, a light emitting unit 10R including a light emitting layer 12R in which a plurality of light emitting regions 12X that emit red light are arranged in a two-dimensional array, a light emitting unit 10G including a light emitting layer 12G in which a plurality of light emitting regions 12X that emit green light are arranged in a two-dimensional array, and a light emitting unit 10B including a light emitting layer 12B in which a plurality of light emitting regions 12X that emit blue light are arranged in a two-dimensional array, stacked in this order, for example, from the side of the drive substrate 20. Each of the light emitting units 10R, 10G, 10B is formed by stacking a first cladding layer 11, a light emitting layer 12 (12R, 12G, 12B), and a second cladding layer 13 in the same order as in the light emitting device 1 of the first embodiment.

[0073] In this modification, the light-emitting region (light-emitting area) of each light-emitting portion 10R, 10G, 10B is determined by the size of the first electrode 14 provided in each light-emitting portion 10R, 10G, 10B. In each light-emitting portion 10R, 10G, 10B, the first electrode 14 is provided on the surface 11S2 side of the first cladding layer 11 for each element separated by the light confinement structure 130. The areas Dr, Dg, and Db of the first electrodes 14 provided in each light-emitting portion 10R, 10G, 10B have a relationship of, for example, Dr > Dg > Db, as shown in FIG. 24 . In this case, each element of each light-emitting portion 10R, 10G, 10B of the light-emitting device 10 has light-emitting regions 12Xr, 12Xg, and 12Xb as shown in FIG. 25 . As in the fifth modification, the second electrode 15 is provided as a common electrode for each element on the surface 13S2, which serves as the light extraction surface of the second cladding layer 13. Except for this point, the light emitting device 1O has substantially the same configuration as the light emitting device 1 of the first embodiment.

[0074] In the light emitting device 1P of this modification, the formation position of the first electrode 14 of each of the light emitting units 10R, 10G, and 10B is shifted in the in-plane direction. By shifting the formation position of the first electrode 14 in the in-plane direction, for example, the positions of the light emitting regions 12Xg and 12Xb of the light emitting unit 10G and the light emitting unit 10B are formed in different positions from each other in a planar view, as shown in Figures 27A and 27B. Except for this point, the light emitting device 1P has substantially the same configuration as the light emitting device 1O of the above modification 9.

[0075] In the light emitting device 1Q of this modification, the width of the light confining structure 130 is changed for each of the light emitting portions 10R, 10G, and 10B, and the widths Wr, Wg, and W2 of the light confining structure 130 for each of the light emitting portions 10R, 10G, and 10B have a relationship of Wr>Wg>Wb, for example, as shown in Fig. 28. Except for this point, the light emitting device 1Q has substantially the same configuration as the light emitting device 1O of the above modification 9.

[0076] 29, the light emitting device 1R of this modification has a light collecting structure (lens 13L) formed on the surface 13S2 of the second cladding layer 13, which serves as the light extraction surface, of the uppermost layer 10B. Except for this point, the light emitting device 1R has substantially the same configuration as the light emitting device 1O of the above modification 9.

[0077] 30 is a schematic diagram showing an example of a cross-sectional configuration of a light emitting device (light emitting device 1S) according to Modification 10 of the present disclosure. Similar to the first embodiment, the light emitting device 1S is suitably applicable to image display devices known as LED displays (for example, the electronic viewfinder 1124 of a digital still camera 1120).

[0078] In the above-described embodiments, examples have been shown in which pixels are isolated by the light confinement structure 130, by both the light confinement structure 110 and the light confinement structure 130, or by forming electrodes, but this is not limiting. In the light emitting device 1S of this modification, pixels are isolated by forming a mesa portion 10M for each element using a groove 19 that penetrates the first cladding layer 11 and the light emitting layer 12 from the surface 11S2 side of the first cladding layer 11 and reaches the second cladding layer 13. Except for this point, the light emitting device 1S has substantially the same configuration as the light emitting device 1 of the first embodiment.

[0079] In this way, in the light emitting device 1A of this modification, the grooves 19 are formed so as to penetrate the first cladding layer 11 and the light emitting layer 12 from the surface 11S2 side of the first cladding layer 11 and reach the second cladding layer 13, thereby mechanically separating the pixels. Even with this configuration, the light emitting device 1S of this modification can achieve the same effects as the light emitting device 1 of the first embodiment.

[0080] 3. Second Embodiment Fig. 34 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device (light-emitting device 2) according to a second embodiment of the present disclosure. Fig. 35 is a schematic diagram illustrating an example of a planar configuration of the light-emitting device 2 illustrated in Fig. 34. Fig. 36 is a schematic diagram illustrating another example of a planar configuration of the light-emitting device 2 illustrated in Fig. 34. Similar to the light-emitting device 1 of the first embodiment, the light-emitting device 2 is suitably applicable to image display devices known as LED displays (e.g., the electronic viewfinder 1124 of a digital still camera 1120, see Fig. 32B).

[0081] The light-emitting device 2 has a first cladding layer 11, a light-emitting layer 12, and a second cladding layer 13 laminated in this order. A light-confining structure 130 is formed in the second cladding layer 13. The light-emitting device 2 further has a condenser lens layer 40 made of an inorganic material on the second cladding layer 13. The condenser lens layer 40 has a plurality of microlenses 40L on its light extraction side S1, and these microlenses 40L are provided for each display pixel P. The condenser lens layer 40 also has grooves 41 between adjacent microlenses 40L. In the light-emitting device 2 of this embodiment, the grooves 41 are formed so that the center of the width direction of each groove 41 substantially coincides with the center of the width direction of the light-confining structure 130.

[0082] Here, the condenser lens layer 40 corresponds to a specific example of a "condenser lens layer" in an embodiment of the present disclosure. The plurality of microlenses 40L corresponds to a specific example of a "plurality of microlenses" in an embodiment of the present disclosure. The groove 41 corresponds to a specific example of a "groove" in an embodiment of the present disclosure.

[0083] [Configuration of Light-Emitting Device] The light-emitting device 2 is formed by laminating a first cladding layer 11, a light-emitting layer 12, and a second cladding layer 13 in this order. In the light-emitting device 2, a drive substrate 20 is disposed on the first cladding layer 11 side, and the second cladding layer 13 side is the light extraction side S1. The first cladding layer 11 has a pair of opposing surfaces (surfaces 11S1 and 11S2), with surface 11S1 facing the light-emitting layer 12. The second cladding layer 13 has a pair of opposing surfaces (surfaces 13S1 and 13S2), with surface 13S1 facing the light-emitting layer 12 and surface 13S2 being the light extraction surface. As described above, the second cladding layer 13 has a light constriction structure 130 formed therein. Similar to the above-described modification 10, the light-emitting device 2 includes a groove 19 extending from the surface 11S2 of the first cladding layer 11 through the first cladding layer 11 and the light-emitting layer 12 to the second cladding layer 13, thereby forming a mesa portion 10M for each element and isolating pixels. A first electrode 14 and a second electrode 15 are electrically connected to the first cladding layer 11 and the second cladding layer 13, respectively. The first electrode 14 is provided on the surface 11S2 side of the first cladding layer 11 and is electrically connected to the first cladding layer 11. An interlayer insulating layer 21 is provided between the first cladding layer 11 and the drive substrate 20. The interlayer insulating layer 21 fills the groove 19 and includes the first electrode 14, the second electrode 15, and a wiring layer 17 within the layer, as well as plugs 18 that connect the second electrode 15 and the wiring layer 17. A plurality of contacts 22 are further embedded within the interlayer insulating layer 21 , and the first cladding layer 11 and the second cladding layer 13 are electrically connected to the drive substrate 20 via the contacts 22 .

[0084] As described above, the light emitting device 2 has the condenser lens layer 40 on the second cladding layer 13 .

[0085] The condenser lens layer 40 is made of an inorganic material and has a plurality of microlenses 40L on its surface (surface 40S1). The plurality of microlenses 40L is provided for each display pixel P, which has a substantially square or substantially regular hexagonal shape and is arranged in a two-dimensional array, as shown in Figures 36A and 36B. The condenser lens layer 40 further has grooves 41 between adjacent microlenses 40L.

[0086] The grooves 41 are provided so as to penetrate the condenser lens layer 40 in its thickness direction (for example, the Z-axis direction). In other words, as shown in Figures 36A and 36B, the grooves 41 are provided between adjacent display pixels P so as to separate the multiple microlenses provided on the surface of the condenser lens layer 40 for each display pixel P.

[0087] In the light emitting device 2, the center C4 of the width W4 of the groove 41 and the center C3 of the width W3 of the light constriction structure 130 are formed so as to approximately coincide with each other, as shown in Fig. 34, for example, although details will be described later. Note that Fig. 34 shows an example in which the width W3 of the light constriction structure 130 and the width W4 of the groove 41 are the same width, but as long as the center C3 of the width W3 of the light constriction structure 130 coincides with each other, as described above, this is not limited to this. For example, the width W3 of the light constriction structure 130 may be formed wider than the width W4 of the groove 41.

[0088] In the light emitting device 2, the light confinement structure 130 is formed by ion implantation of impurities, and an impurity region 42 is formed on the side of the groove 41, into which the same impurities as those constituting the light confinement structure 130 have been implanted.

[0089] 36A to 36E are schematic diagrams showing examples of the cross-sectional shape of the microlenses 40L. The multiple microlenses 40L on the surface of the condensing lens layer 40 may have a trapezoidal shape, as shown in FIG. 36A, in addition to the convex shape shown in FIG. 34. The multiple microlenses 40L on the surface of the condensing lens layer 40 may also have a polygonal shape, as shown in FIG. 36B, or a concave shape, as shown in FIG. 36C. The multiple microlenses 40L on the surface of the condensing lens layer 40 may also be a Fresnel lens, as shown in FIG. 36D, or a metalens in which multiple fine structures 43 are arranged in a predetermined pattern, as shown in FIG. 36E.

[0090] [Method of Manufacturing Light-Emitting Device] The light-emitting device 2 can be manufactured, for example, as follows: Figures 37A to 37I show an example of a manufacturing process for the light-emitting device 2.

[0091] First, as shown in Fig. 37A , in the same manner as in the first embodiment, the second cladding layer 13, the light-emitting layer 12, and the first cladding layer 11 are laminated in this order on the support substrate 30. Next, as shown in Fig. 37A , a groove 19 is formed by, for example, photolithography, to reach the second cladding layer 13, thereby forming the mesa portion 10M. Subsequently, as shown in Fig. 37A , an insulating layer 21A is formed over the surface 13S1 of the second cladding layer 13 exposed at the bottom of the groove 19 and over the side and top surfaces of the mesa portion 10M.

[0092] Next, as shown in Figure 37B, a first electrode 14 connected to the surface 11S2 of the first cladding layer 11, a second electrode 15 connected to the surface 13S1 of the second cladding layer 13, and a wiring layer 17 are formed, for example, by photolithography technology.

[0093] 37C, an insulating layer is further formed to fill the grooves 19 to form an interlayer insulating layer 21, and then plugs 18 are formed by, for example, photolithography. Thereafter, as shown in FIG. 37C, a drive substrate 20 is bonded onto the interlayer insulating layer 21.

[0094] Next, as shown in FIG. 37D, the support substrate 30 is peeled off.

[0095] 37E, a silicon oxide film is formed as the condenser lens layer 40 on the surface 13S2 of the second cladding layer 13. Next, as shown in Fig. 37E, a resist film 202 is patterned on the condenser lens layer 40, and then a groove 41 is formed by, for example, photolithography, penetrating between the opposing surfaces 41S1 and 41S2 of the condenser lens layer 40.

[0096] 37F , the impurity concentration of the second cladding layer 13 exposed at the bottom of the groove 41 is controlled by ion implantation to form the light constriction structure 130. At this time, impurities are also implanted into the condenser lens layer 40 on the side surface of the groove 41 to form impurity regions 42. In this way, the light constriction structure 130 is formed via the groove 41 formed in the condenser lens layer 40, and therefore the center of the light constriction structure 130 in the width direction substantially coincides with the center of the groove 41 in the width direction.

[0097] Next, as shown in FIG. 37G, the resist film 202 is removed by surface etch-back to expose the condenser lens layer 40 .

[0098] Subsequently, as shown in FIG. 37H, a resist film 203 for lenses is patterned on the exposed condenser lens layer 40.

[0099] 37I, the surface of the condenser lens layer 40 is processed by, for example, etching to form a plurality of microlenses 40L. In this way, the light emitting device 2 shown in FIG.

[0100] The above-described manufacturing method is merely an example, and other manufacturing methods may be adopted.

[0101] For example, in the above-described manufacturing method, an example has been shown in which the light constriction structure 130 is formed and then the surface of the condenser lens layer 40 is processed to form the plurality of microlenses 40L, but the present invention is not limited to this. For example, the grooves 41 may be formed in advance and the surface of the condenser lens layer 40 may be processed to form the plurality of microlenses 40L, and then ion implantation may be performed using the condenser lens layer 40 with the processed surface as a mask to form the light constriction structure 130.

[0102] [Actions and Effects] The light-emitting device 2 of the present embodiment has a configuration in which a first cladding layer 11, a light-emitting layer 12, and a second cladding layer 13 are laminated in this order, and a light constriction structure 130 is provided in the second cladding layer 13, which serves as a light extraction surface, and a condenser lens layer 40 made of an inorganic material is provided on the second cladding layer 13. The condenser lens layer 40 has a plurality of microlenses 40L on its light extraction side S1 for each display pixel P, and has grooves 41 between adjacent microlenses 40L. The centers of the grooves 41 in the width direction and the centers of the light constriction structure 130 in the width direction are formed to approximately coincide with each other.

[0103] In other words, the light emitting device 2 of this embodiment is configured so that there is no misalignment between the microlens 40L formed for each display pixel P and the light confinement structure 130 provided between the display pixels P. This makes it possible to improve the light utilization efficiency in the light emitting device 2 of this embodiment. In addition, the light emitting device 2 of this embodiment reduces variations in the light distribution. Therefore, in an image display device including this light emitting device 2, in addition to the effects of the first embodiment described above, it is possible to minimize unevenness in brightness and color on the screen.

[0104] Furthermore, in the light emitting device 2 of this embodiment, compared to the light emitting device 1G of Modification 7 in which a light collection structure is formed on the surface 13S2 serving as the light extraction surface of the second cladding layer 13, the microlens 40L can be formed with high precision for each display pixel P. In other words, in the light emitting device 2 of this embodiment, the yield can be improved, and therefore the manufacturing cost can be reduced.

[0105] 38 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device (light-emitting device 2A) according to Modification 11 of the present disclosure. Similar to the first embodiment, light-emitting device 2A is suitable for use in image display devices known as LED displays (for example, electronic viewfinder 1124 of digital still camera 1120).

[0106] In the light emitting device 2A of this modification, a light-shielding film 44 is embedded in the grooves 41 provided between the adjacent microlenses 40L. Except for this point, the light emitting device 2A has substantially the same configuration as the light emitting device 2 of the second embodiment.

[0107] The light-shielding film 44 corresponds to a specific example of a "light-shielding film" according to an embodiment of the present disclosure, and is intended to prevent color mixing with adjacent display pixels P. The light-shielding film 44 can be formed using, for example, a black matrix, a light-absorbing material, a light-reflecting material, or the like. Examples of light-absorbing materials include carbon (C). Examples of light-reflecting materials include metal materials such as aluminum (Al), silver (Ag), chromium (Cr), and nickel (Ni). The light-shielding film 44 can be a single-layer film made of any of the above materials, or a laminated film made by selecting multiple types of the above materials and stacking them at a predetermined interval.

[0108] In this way, in the light emitting device 2A of this modified example, the grooves 41 provided between the adjacent microlenses 40L are filled with the light-shielding film 44. This makes it possible to prevent color mixing with adjacent display pixels P in addition to the effect of the second embodiment.

[0109] 39 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device (light-emitting device 2B) according to Modification 12 of the present disclosure. Similar to the first embodiment, light-emitting device 2B is suitable for use in image display devices known as LED displays (for example, electronic viewfinder 1124 of digital still camera 1120).

[0110] In the light emitting device 2B of this modification, the side surfaces 41S of the grooves 41 provided between adjacent microlenses 40L are inclined surfaces whose width gradually narrows from the light extraction side S1 toward the second cladding layer 13. Except for this point, the light emitting device 2B has substantially the same configuration as the light emitting device 2 of the second embodiment and the light emitting device 2A of modification 11.

[0111] Even with this configuration, the light emitting device 2B of this modification can achieve the same effects as the light emitting device 2 of the second embodiment and the light emitting device 2A of the eleventh modification.

[0112] 40 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device (light-emitting device 2C) according to Modification 13 of the present disclosure. Similar to the first embodiment, light-emitting device 2C is suitable for use in image display devices known as LED displays (for example, electronic viewfinder 1124 of digital still camera 1120).

[0113] In the second embodiment, an example in which a mesa portion 10M is formed for each display pixel P is shown, but the present invention is not limited to this. Similar to the light emitting device 1 of the first embodiment and the light emitting device 1D of the fourth modification, the light emitting device 2C of this modification has the first cladding layer 11 and the light emitting layer 12 extended into the pixel array portion 100A as common layers for a plurality of display pixels P. Except for this point, the light emitting device 2C has substantially the same configuration as the light emitting device 2 of the second embodiment.

[0114] Even with this configuration, the light emitting device 2C of this modified example can achieve the same effects as the light emitting device 2 of the second embodiment.

[0115] 41 is a schematic diagram illustrating an example of a cross-sectional configuration of a light-emitting device (light-emitting device 2D) according to Modification 14 of the present disclosure. Similar to the first embodiment, light-emitting device 2D is suitable for use in image display devices known as LED displays (for example, electronic viewfinder 1124 of digital still camera 1120).

[0116] In the second embodiment, pixel separation is performed by forming a mesa portion 10M for each display pixel P, but this is not limiting. Similar to the above-described modification 13, the light emitting device 2D of this modification is configured such that the first cladding layer 11 extending to the pixel array portion 100A as a common layer for a plurality of display pixels P is provided with a light confinement structure 110, as in the light emitting device 1H of modification 8. Except for this point, the light emitting device 2D has substantially the same configuration as the light emitting device 2 of the above-described second embodiment.

[0117] Even with this configuration, the light emitting device 2D of this modified example can achieve the same effects as the light emitting device 2 of the second embodiment.

[0118] (4-5. Other Modifications) The techniques described in the light emitting devices 1, 1A to 1S, 2, and 2A to 2D shown in the first and second embodiments and modifications 1 to 14 can be combined as appropriate.

[0119] For example, by combining the light emitting device 2A shown in Modification 1 with the light emitting device 2C shown in Modification 3, the grooves 41 of the light emitting device 2C may be formed with a light-shielding film 44. Furthermore, by combining the light emitting device 2B shown in Modification 2, the grooves 41 of the light emitting device 2C may be formed with a side surface 41S of the grooves 41 having a tapered angle. Similarly, by combining the light emitting device 2A shown in Modification 1 with the light emitting device 2D shown in Modification 4, the grooves 41 of the light emitting device 2D may be formed with a light-confining structure 110 in the first cladding layer 11 as a common layer for the plurality of display pixels P. Furthermore, by combining the light emitting device 2B shown in Modification 2, the grooves 41 of the light emitting device 2D may be formed with a light-shielding film 44. Furthermore, by combining the light emitting device 2B shown in Modification 2, the grooves 41 of the light emitting device 2D may be formed with a side surface 41S of the grooves 41 having a tapered angle.

[0120] 5. Application Examples Application Example 1 Fig. 31A is a front view showing an example of the appearance of a digital still camera (electronic device) 1120. Fig. 31B is a rear view showing an example of the appearance of the digital still camera 1120. The digital still camera 1120 is an interchangeable lens single-lens reflex camera. The digital still camera 1120 has an interchangeable taking lens unit (interchangeable lens) 1121 located approximately in the center of the front of a camera main body (camera body) 1122, and a grip portion 1123 for the photographer to hold on the left side of the front.

[0121] A monitor 1126 is provided at a position shifted to the left from the center of the back of the camera body 1122. An electronic viewfinder (eyepiece window) 1124 is provided above the monitor 1126. By looking through the electronic viewfinder 1124, the photographer can visually confirm the optical image of the subject guided by the photographing lens unit 1121 and determine the composition. The electronic viewfinder 1124 is equipped with a light-emitting device 1.

[0122] (Application Example 2) The light-emitting device (e.g., the light-emitting device 1) of the present disclosure can also be applied to a head-mounted display (hereinafter referred to as an HMD). The head-mounted display 1130A can be used for virtual reality (VR), augmented reality (AR), mixed reality (MR), substitutional reality (SR), or the like.

[0123] 32A is a perspective view showing the appearance of a head-mounted display (electronic device) 1130A. The head-mounted display 1130A has, for example, ear hooks 1131 on both sides of a glasses-shaped display unit 1132 for wearing on the user's head. The display unit 1132 is equipped with a light-emitting device 1.

[0124] FIG. 32B is a perspective view showing the appearance of another head-mounted display (electronic device). The head-mounted display is smart glasses 1130B that display various information on glasses 1133. The smart glasses 1130B include a main body, an arm 1135, and a lens barrel 1136. The main body 1134 is connected to the arm 1135. The main body 1134 is detachable from the glasses 1133. The main body 1134 incorporates a control board and a display unit for controlling the operation of the smart glasses 1130B. The main body 1134 and the lens barrel 1136 are connected to each other via the arm 1135. The lens barrel 1136 emits image light emitted from the main body 1134 via the arm 1135 toward the lenses 1137 of the glasses 1133. This image light enters the human eye through the lens 1137. 32B, a wearer of the smart glasses 1130B can visually recognize not only the surrounding situation but also various pieces of information emitted from the lens barrel 1136, as with normal glasses. The main body 1134 includes the light-emitting device 1.

[0125] 33 is a perspective view showing an example of the appearance of a television device (electronic device) 1140. This television device 1140 has, for example, an image display screen unit 1141 including a front panel 1142 and a filter glass 1143. The image display screen unit 1141 is equipped with the light-emitting device 1.

[0126] Although the present disclosure has been described above using the first and second embodiments, Modifications 1 to 14, and application examples, the present disclosure is not limited to the above-described embodiments, etc., and various modifications are possible. For example, two or more of Modifications 1 to 8 may be combined.

[0127] The effects described in this specification are merely examples and are not limited to those described, and other effects may also be obtained.

[0128] The present technology can also be configured as follows. According to the present technology configured as follows, it is possible to reduce the spread of light in an in-plane direction perpendicular to the stacking direction of each layer without obstructing the optical path of light emitted from the light-emitting layer. This makes it possible to improve external quantum efficiency. (1) A light-emitting device comprising: a first conductivity-type layer; a second conductivity-type layer; a light-emitting layer provided between the first conductivity-type layer and the second conductivity-type layer; and a light-confining structure formed in at least one of the first conductivity-type layer and the second conductivity-type layer. (2) The light-emitting device according to (1), wherein the second conductivity-type layer has a first surface facing the light-emitting layer and a second surface opposite to the first surface, the second surface serving as a light extraction surface, and the light-confining structure is formed in the second conductivity-type layer. (3) The light-emitting device according to (2), wherein the light-confining structure penetrates between the first surface and the second surface of the second conductivity-type layer. (4) The light-emitting device according to (2), wherein the light confinement structure is formed in the second conductive type layer from the second surface toward the first surface and has a bottom within the layer. (5) The light-emitting device according to any one of (2) to (4), wherein the light-emitting layer has one or more light-emitting regions within the layer, and the light confinement structure is formed to surround each of the plurality of light-emitting regions individually in a planar view. (6) The light-emitting device according to (5), wherein the light confinement structure that surrounds each of the one or more light-emitting regions individually is partially separated in a planar view. (7) The light-emitting device according to (5) or (6), further comprising: a first electrode electrically connected to the first conductive type layer; a second electrode electrically connected to the second conductive type layer; and an opening that penetrates the first conductive type layer and the light-emitting layer to reach the second conductive type layer, and the second electrode is electrically connected to the second conductive type layer from the first conductive type layer side through the opening. (8) The light emitting device according to (7), wherein the second electrode and the opening are provided for each of the one or more light emitting regions individually surrounded by the light confinement structure. (9) The light emitting device according to (7) or (8), wherein the plurality of light emitting regions are arranged in an array within the light emitting layer, and the second electrode and the opening are provided on the periphery of the plurality of light emitting regions arranged in the array.(10) The light-emitting device according to any one of (7) to (9), wherein the first conductivity type layer has a third surface facing the light-emitting layer and a fourth surface opposite to the third surface, and the first electrode is provided on the fourth surface of the first conductivity type layer for each of the one or more light-emitting regions individually surrounded by the light confinement structure. (11) The light-emitting device according to any one of (5) to (10), further comprising: a first electrode electrically connected to the first conductivity type layer; and a second electrode electrically connected to the second conductivity type layer, and the second electrode is provided on the second surface as a common electrode for the multiple light-emitting regions. (12) The light-emitting device according to any one of (5) to (11), wherein the second conductivity type layer has a light-collecting structure for each of the one or more light-emitting regions. (13) The light-emitting device according to any one of (2) to (12), wherein the light-emitting layer has one or more light-emitting regions therein, and the first conductive type layer and the light-emitting layer are separated into one or more light-emitting regions by grooves that penetrate the first conductive type layer and the light-emitting layer and reach the second conductive type layer. (14) The light-emitting device according to any one of (1) to (13), wherein the light-confining structure is formed in the first conductive type layer. (15) The light-emitting device according to any one of (1) to (14), wherein the light-confining structure includes a first light-confining structure formed in the first conductive type layer and a second light-confining structure formed in the second conductive type layer. (16) The light-emitting device according to (15), wherein the width of the second light-confining structure is narrower than the width of the first light-confining structure. (17) The light-emitting device according to (16), wherein the light-confining structure is formed by an impurity region. (18) The light-emitting device according to any one of (2) to (17), further comprising a condensing lens layer made of an inorganic material on the second surface of the second conductive type layer, wherein the condensing lens layer has a plurality of microlenses arranged in an array and grooves between adjacent microlenses, and the center of the groove in the width direction substantially coincides with the center of the light constriction structure in the width direction.(19) The light-emitting device according to (18), wherein the light confining structure is formed of an impurity region, and the condensing lens layer contains the impurity contained in the light confining structure on a side surface of the groove. (20) The light-emitting device according to (18) or (19), wherein the groove is filled with a black matrix or a light-shielding film containing a light-absorbing material or a light-reflecting material. (21) The light-emitting device according to any one of (18) to (20), wherein the condensing lens layer has a fifth surface facing the second surface of the second conductivity type layer and a sixth surface on which the plurality of microlenses are formed on the opposite side to the fifth surface, and the side surface of the groove has a tapered angle whose width gradually narrows from the sixth surface toward the fifth surface. (22) An image display device comprising a light-emitting device having: a first conductivity type layer, a second conductivity type layer, a light-emitting layer provided between the first conductivity type layer and the second conductivity type layer, and a light constriction structure formed in at least one of the first conductivity type layer and the second conductivity type layer. (23) A method for manufacturing a light-emitting device, comprising: depositing an inorganic material layer on a side of the second conductive layer of a semiconductor laminate in which a first conductivity type layer, a light-emitting layer, and a second conductivity type layer are laminated in order; forming grooves in the inorganic material layer that have a predetermined pattern and that penetrate the inorganic material layer; injecting impurities into the second conductivity type layer through the grooves to form the light constriction structure; and processing a surface of the inorganic material layer to form a plurality of microlenses.

[0129] This application claims priority based on Japanese Patent Application No. 2024-058023, filed on March 29, 2024, in the Japan Patent Office, the entire contents of which are incorporated herein by reference.

[0130] Those skilled in the art will recognize that various modifications, combinations, subcombinations, and variations may occur depending on design requirements and other factors, and are intended to be within the scope of the appended claims and their equivalents.

Claims

1. A light-emitting device comprising: a first conductive type layer; a second conductive type layer; a light-emitting layer provided between the first conductive type layer and the second conductive type layer; and a light-confining structure formed in at least one of the first conductive type layer and the second conductive type layer.

2. The light-emitting device described in claim 1, wherein the second conductive type layer has a first surface facing the light-emitting layer and a second surface opposite the first surface that serves as a light extraction surface, and the light confinement structure is formed in the second conductive type layer.

3. The light emitting device according to claim 2, wherein the light confinement structure penetrates between the first surface and the second surface of the second conductive type layer.

4. The light emitting device according to claim 2, wherein the light confining structure is formed in the second conductive type layer from the second surface toward the first surface and has a bottom within the layer.

5. The light emitting device according to claim 2, wherein the light emitting layer has one or more light emitting regions therein, and the light confinement structure is formed so as to surround each of the plurality of light emitting regions individually in a plan view.

6. The light emitting device according to claim 5, wherein the light confining structures individually surrounding the one or more light emitting regions are partially separated in plan view.

7. A light-emitting device as described in claim 5, further comprising: a first electrode electrically connected to the first conductivity type layer; a second electrode electrically connected to the second conductivity type layer; and an opening that passes through the first conductivity type layer and the light-emitting layer and reaches the second conductivity type layer, wherein the second electrode is electrically connected to the second conductivity type layer from the first conductivity type layer side through the opening.

8. The light emitting device according to claim 7, wherein the second electrode and the opening are provided for each of the one or more light emitting regions individually surrounded by the light confinement structure.

9. The light-emitting device according to claim 7, wherein the plurality of light-emitting regions are arranged in an array within the light-emitting layer, and the second electrode and the opening are provided on the periphery of the plurality of light-emitting regions arranged in the array.

10. The light-emitting device described in claim 7, wherein the first conductive type layer has a third surface facing the light-emitting layer and a fourth surface opposite the third surface, and the first electrode is provided on the fourth surface of the first conductive type layer for each of the one or more light-emitting regions individually surrounded by the light confinement structure.

11. The light-emitting device according to claim 5, further comprising: a first electrode electrically connected to the first conductivity type layer; and a second electrode electrically connected to the second conductivity type layer, wherein the second electrode is provided on the second surface as a common electrode for the plurality of light-emitting regions.

12. The light-emitting device according to claim 5, wherein the second conductive type layer has a light-collecting structure for each of the one or more light-emitting regions.

13. The light-emitting device according to claim 2, wherein the light-emitting layer has one or more light-emitting regions therein, and the first conductive type layer and the light-emitting layer are separated into each of the one or more light-emitting regions by grooves that penetrate the first conductive type layer and the light-emitting layer and reach the second conductive type layer.

14. The light emitting device according to claim 1, wherein the light confinement structure is formed in the first conductivity type layer.

15. The light emitting device according to claim 1, wherein the light confinement structure comprises a first light confinement structure formed in the first conductive type layer and a second light confinement structure formed in the second conductive type layer.

16. The light emitting device according to claim 15, wherein the width of the second light confining structure is narrower than the width of the first light confining structure.

17. The light emitting device according to claim 16, wherein the light confinement structure is formed by an impurity region.

18. A light-emitting device as described in claim 2, further comprising a focusing lens layer made of an inorganic material on the second surface of the second conductive type layer, the focusing lens layer having a plurality of microlenses arranged in an array with grooves between adjacent microlenses, and the center of the groove in the width direction substantially coincides with the center of the light constriction structure in the width direction.

19. The light emitting device according to claim 18, wherein the light confinement structure is formed by an impurity region, and the condenser lens layer contains the impurity contained in the light confinement structure on the side surface of the groove.

20. An image display device comprising a light-emitting device, the light-emitting device having: a first conductive type layer; a second conductive type layer; a light-emitting layer provided between the first conductive type layer and the second conductive type layer; and a light-confining structure formed in at least one of the first conductive type layer and the second conductive type layer.

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