Light emitting element

Abstract

This light-emitting element of the present disclosure comprises: a laminated structure 20 in which are laminated a first compound semiconductor layer 21 having a first surface 21a, and a second surface 21b opposing the first surface 21a, an active layer 23 facing the second surface 21b of the first compound semiconductor layer 21, and a second compound semiconductor layer 22 having a second surface 22a facing the active layer 23, and a second surface 22b opposing the first surface 22a; a first light reflective layer 41 formed on the first surface side of the first compound semiconductor layer 21; a second light reflective layer 42 formed on the second surface side of the second compound semiconductor layer 22; a first electrode 31 electrically connected to the first compound semiconductor layer 41; and a second electrode 42 provided between the second compound semiconductor layer 22 and the second light reflective layer 42, the second electrode 32 having at least a nano-carbon material layer or a two-dimensional material layer.

Description

[Technical field]

[0001] The present disclosure relates to light emitting devices, and more particularly to light emitting devices comprising vertical cavity surface emitting laser devices (VCSELs). [Background technology]

[0002] For example, in a light-emitting element consisting of a surface-emitting laser element disclosed in WO2018 / 083877A1, laser oscillation occurs by resonating laser light between two light reflecting layers (Distributed Bragg Reflector layer, DBR layer). In a surface-emitting laser element having a laminated structure in which an n-type compound semiconductor layer (first compound semiconductor layer), an active layer (light-emitting layer) consisting of a compound semiconductor, and a p-type compound semiconductor layer (second compound semiconductor layer) are laminated, a second electrode consisting of a transparent conductive material is formed on the p-type compound semiconductor layer, and a second light reflecting layer is formed on the second electrode. In addition, a first light reflecting layer and a first electrode are formed on the n-type compound semiconductor layer (on the exposed surface of the substrate when the n-type compound semiconductor layer is formed on a conductive substrate). In this specification, the concept of "upper" may refer to a direction away from the active layer with respect to the active layer, the concept of "lower" may refer to a direction approaching the active layer with respect to the active layer, and the concepts of "convex" and "concave" may refer to the active layer with respect to the active layer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2018 / 083877A1 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the transparent conductive material constituting the second electrode generally has a high electrical resistance, so when the area of ​​the active layer (light-emitting layer) is increased, the area of ​​the second electrode also inevitably becomes large, which may make it difficult for a current to flow uniformly through the second electrode and further through the active layer.

[0005] Therefore, an object of the present disclosure is to provide a light emitting device having a configuration and structure that allows a current to flow uniformly through an active layer. [Means for solving the problem]

[0006] In order to achieve the above object, the light-emitting device of the present disclosure comprises: a first compound semiconductor layer having a first surface and a second surface opposite to the first surface; an active layer facing the second surface of the first compound semiconductor layer; and a second compound semiconductor layer having a first surface facing the active layer and a second surface opposite to the first surface; A laminated structure in which a first light reflecting layer formed on the first surface side of the first compound semiconductor layer; a second light reflecting layer formed on the second surface side of the second compound semiconductor layer; a first electrode electrically connected to the first compound semiconductor layer; and a second electrode provided between the second compound semiconductor layer and the second light reflecting layer; Equipped with The second electrode includes at least a nanocarbon material layer or a two-dimensional material layer. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic partial end view of the light-emitting element of the first embodiment. [Diagram 2] FIG. 2 is a schematic partial end view of Modification 1 of the light-emitting device of Example 1. FIG. [Diagram 3] FIG. 3 is a schematic partial end view of Modification 2 of the light emitting device of Example 1. FIG. [Figure 4] FIG. 4 is a schematic partial end view of Modification 3 of the light emitting device of Example 1. As shown in FIG. [Diagram 5] FIG. 5 is a schematic partial end view of Modification 4 of the light emitting device of Example 1. As shown in FIG. [Figure 6] FIG. 6 is a schematic partial end view of the light emitting device of Example 3. As shown in FIG. [Figure 7] FIG. 7 is a schematic partial end view of the light emitting device of Example 4. As shown in FIG. [Figure 8] FIG. 8 is a schematic partial end view of Modification 1 of the light-emitting device of Example 4. As shown in FIG. [Figure 9] FIG. 9 is a schematic partial end view of the light-emitting element of Example 5. As shown in FIG. [Figure 10] FIG. 10 is a schematic partial end view of a light-emitting element array constituted by the light-emitting elements of the fifth embodiment. [Figure 11] FIG. 11 is a diagram illustrating an arrangement of a first light reflecting layer and a first electrode in the light emitting element of Example 5. As shown in FIG. [Figure 12] FIG. 12 is a diagram illustrating another example of the arrangement of the first light reflecting layer and the first electrode in the light emitting element of Example 5. In FIG. [Figure 13] FIG. 13 is a schematic partial end view of the light-emitting device of Example 6. As shown in FIG. [Figure 14] FIG. 14 is a schematic partial end view of a light-emitting element array constituted by light-emitting elements according to the sixth embodiment. [Figure 15] FIG. 15 is a schematic plan view showing the arrangement of the first and second portions of the base surface in a light-emitting element array constituted by light-emitting elements of Example 6. As shown in FIG. [Figure 16] FIG. 16 is a schematic plan view showing the arrangement of first light reflecting layers and first electrodes in a light emitting element array constituted by light emitting elements of Example 6. As shown in FIG. [Figure 17] FIG. 17 is a schematic plan view showing the arrangement of the first and second portions of the base surface in a light-emitting element array constituted by light-emitting elements of Example 6. FIG. [Figure 18] FIG. 18 is a schematic plan view showing the arrangement of first light reflecting layers and first electrodes in a light emitting element array constituted by light emitting elements of Example 6. As shown in FIG. [Figure 19]FIG. 19 is a schematic partial end view of a light-emitting element array constituted by the light-emitting elements of Example 7. As shown in FIG. [Figure 20] FIG. 20 is a schematic partial end view of a light-emitting element array constituted by a modified example of the light-emitting element of the seventh embodiment. [Figure 21] FIG. 21 is a schematic plan view showing the arrangement of the first portion and the like in a light-emitting element array constituted by a modified example of the light-emitting element of Example 7. As shown in FIG. [Figure 22] 22A and 22B are schematic plan views showing the arrangement of the first portion and the second portion of the base surface in the light-emitting element array of Example 8. FIG. [Figure 23] FIG. 23 is a schematic partial cross-sectional view of a light-emitting element array constituted by a plurality of light-emitting elements of Example 10. As shown in FIG. [Figure 24] FIG. 24 is a schematic partial cross-sectional view of the light-emitting device of Example 10. As shown in FIG. [Diagram 25] FIG. 25 is a schematic partial cross-sectional view of a light-emitting element array constituted by a plurality of light-emitting elements according to Modification 1 of the tenth embodiment. [Figure 26] FIG. 26 is a schematic partial cross-sectional view of Modification 1 of the light-emitting device of Example 10. As shown in FIG. [Figure 27] FIG. 27 is a schematic partial cross-sectional view of the light-emitting element array of the eleventh embodiment. [Figure 28] FIG. 28 is a schematic partial cross-sectional view of the light-emitting device of Example 11. As shown in FIG. [Figure 29] FIG. 29 is a schematic partial cross-sectional view of Modification 1 of the light-emitting device of Example 11. As shown in FIG. [Diagram 30] FIG. 30 is a schematic partial cross-sectional view of Modification 2 of the light-emitting device of Example 11. As shown in FIG. [Diagram 31] FIG. 31 is a schematic partial cross-sectional view of Modification 3 of the light-emitting device in Example 11. As shown in FIG. [Diagram 32] 32A and 32B are schematic partial end views of a laminated structure and the like for explaining a manufacturing method of the light emitting device of Example 1. FIG. [Diagram 33]FIG. 33 is a schematic partial end view of the laminated structure etc. for explaining the manufacturing method of the light emitting element of Example 1, following FIG. 32B. [Diagram 34] FIG. 34 is a schematic partial end view of the laminated structure etc. for explaining the manufacturing method of the light emitting device of Example 1, following FIG. [Diagram 35] 35A, 35B, and 35C are schematic partial end views of a first compound semiconductor layer and the like for explaining the manufacturing method of the light-emitting element of Example 1, following FIG. [Diagram 36] 36A, 36B, and 36C are schematic partial end views of a laminated structure and the like for illustrating a manufacturing method of a light-emitting element according to Example 5. FIG. [Figure 37] 37A, 37B, and 37C are schematic partial end views of a laminated structure and the like for illustrating a manufacturing method of a light-emitting element according to Example 5. FIG. [Figure 38] 38A and 38B are schematic partial end views of the laminated structure and the like for illustrating the manufacturing method of the light-emitting element of Example 5, following FIG. 36C. [Figure 39] 39A and 39B are schematic partial end views of a first compound semiconductor layer and the like for illustrating a manufacturing method of a light emitting device in Example 6. FIG. [Diagram 40] 40A and 40B are schematic partial end views of a first compound semiconductor layer etc. for explaining the manufacturing method of the light emitting device of Example 6, following FIG. 39B. [Diagram 41] 41A and 41B are schematic partial end views of a first compound semiconductor layer etc. for explaining the manufacturing method of the light emitting device of Example 6, following FIG. 40B. [Diagram 42] 42A, 42B, and 42C are schematic partial end views of a laminated structure and the like for illustrating a manufacturing method of the light-emitting device of Example 9. FIG. [Diagram 43] 43A and 43B are conceptual diagrams that typically show longitudinal modes present in a gain spectrum determined by an active layer. [Diagram 44]44A, 44B, 44C, and 44D are diagrams that show a schematic diagram of a change in the forbidden band due to a change in the Fermi level Ef in the band structure of graphene. [Diagram 45] FIG. 45 is a schematic partial cross-sectional view of the light-emitting device of Example 1, and a diagram in which two longitudinal modes, longitudinal mode A and longitudinal mode B, are superimposed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the present disclosure will be described based on examples with reference to the drawings, but the present disclosure is not limited to the examples, and various numerical values ​​and materials in the examples are merely examples. The description will be made in the following order. 1. General Description of the Light-Emitting Device of the Present Disclosure 2. Example 1 (Light-emitting device of the present disclosure) 3. Example 2 (Modification of Example 1) 4. Example 3 (Modification of Examples 1 and 2) 5. Example 4 (another modification of Examples 1 and 2) 6. Example 5 (Modification of Examples 1 to 4) 7. Example 6 (Modification of Example 5) 8. Example 7 (Modification of Examples 5 to 6) 9. Example 8 (Modification of Example 5) 10. Example 9 (Modification of Example 5, Example 4, and Example 5) 11. Example 10 (Modification of Examples 1 to 5) 12. Example 11 (Modification of Example 10) 13.Other

[0009] <General Description of Light-Emitting Element of the Present Disclosure> In the light-emitting device of the present disclosure, the nanocarbon material layer can be made of at least one material selected from the group consisting of graphene, carbon nanotube, and fullerene. The two-dimensional material layer can be made of at least one material selected from the group consisting of silicene, germanene, stanene, plumbene, boron nitride (specifically, hexagonal boron nitride), and transition metal dichalcogenide-based materials, and in this case, when the transition metal dichalcogenide (TMDC)-based material is represented by MX2, the transition metal "M" is one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Mo, W, Tc, and Re, and the chalcogen element "X" is one element selected from the group consisting of O, S, Se, and Te. Alternatively, CuS, which is a compound of Cu, a transition metal, and S, a chalcogen element, can be mentioned, as well as compounds of non-transition metals such as Ga, In, Ge, Sn, and Pb, and chalcogen elements (e.g., GaS, GaSe, GaTe, In2Se3, InSnS2, SnSe2, GeSe, SnS2, PbO), and black phosphorus can also be mentioned. Graphene is a single-atom-thick sp 2 It refers to a sheet-like material of bonded carbon atoms, and has a hexagonal lattice structure like a honeycomb made from carbon atoms and their bonds. Silicene is a graphene-like material in which the carbon atoms of graphene are replaced with silicon elements and crystallized in a honeycomb lattice, Germanene is a graphene-like material in which the carbon atoms of graphene are replaced with germanium elements and crystallized in a honeycomb lattice, Stanene is a graphene-like material in which the carbon atoms of graphene are replaced with tin elements and crystallized in a honeycomb lattice, and Plumbene is a graphene-like material in which the carbon atoms of graphene are replaced with lead elements and crystallized in a honeycomb lattice, and these materials are also called post-graphene materials. The second electrode may have a laminated structure of at least a nanocarbon material layer and a two-dimensional material layer.

[0010] In the light-emitting device of the present disclosure including the above preferred embodiment, the second electrode may have a laminated structure of at least a first layer made of a transparent conductive material or a semiconductor material, and a second layer made of a nanocarbon material layer or a two-dimensional material layer. In this case, the first layer may be in contact with the second compound semiconductor layer. Furthermore, the second layer may not be formed in the center of the second electrode, thereby making it possible to suppress emission of high-order mode light emitted from the active layer. The diameter of the region where the second layer is not formed is defined as R. CL The second electrode may have a laminated structure of, for example, a first layer made of a transparent conductive material or a semiconductor material, a second layer made of a nanocarbon material layer or a two-dimensional material layer, and a third layer made of a transparent conductive material or a semiconductor material. Hereinafter, the nanocarbon material layer and the two-dimensional material layer may be collectively referred to as "nanocarbon material layer, etc."

[0011] In the embodiment in which the second layer is not formed in the center of the second electrode, the second layer is preferably disposed at a position that does not satisfy the following formula (A). This allows the second layer (nanocarbon material layer, etc.) to function as a light absorbing material layer and absorb the high-order mode light emitted from the active layer, thereby ensuring transverse mode control of the light emitted from the active layer.

[0012] The length L of the cavity formed by the first light reflecting layer and the second light reflecting layer OR However, if the wavelength is several times longer than the wavelength of the light emitted from the light-emitting element, the nanocarbon material layer, etc., will absorb the light emitted from the light-emitting element, resulting in multiple types of longitudinal mode light that can be emitted from the light-emitting element (see conceptual diagram in Figure 43B), which may make it difficult to accurately control the oscillation wavelength of the light emitted from the light-emitting element.

[0013] Therefore, in the light-emitting device of the present disclosure including the preferred embodiment described above, the distance in the thickness direction of the laminate structure from the center of the active layer in the thickness direction to the center of the nanocarbon material layer or the two-dimensional material layer in the thickness direction is L2, the oscillation wavelength is λ0, and the equivalent refractive index of the part located from the center of the active layer in the thickness direction to the center of the nanocarbon material layer or the two-dimensional material layer in the thickness direction is n eq When 0.9×{(m+1)λ0) / (4 n eq )}≦L2≦1.1×{(m+1)λ0) / (4·n eq )} (A) Here, m is an arbitrary integer of 2 or more including 0 or 1. By adopting such a configuration, it becomes possible to position the nanocarbon material layer constituting the second electrode in the minimum amplitude portion of the light intensity distribution, so that the nanocarbon material layer constituting the second electrode is less likely to absorb the light generated in the active layer, and the light in the longitudinal mode that can be emitted from the light emitting element becomes one type (see the conceptual diagram of FIG. 43A), making it possible to accurately control the oscillation wavelength of the light in the longitudinal mode emitted from the light emitting element, improving the light emitting efficiency of the light emitting element, and the oscillation wavelength of the light emitted from the light emitting element becomes single, making it possible to accurately control the emission wavelength. Here, the equivalent refractive index n eq The thickness of each layer made of various materials that constitutes the part located from the center of the active layer in the thickness direction to the center of the nanocarbon material layer, etc. in the thickness direction is t i , and the refractive index of each is n i When n eq =Σ(t i ×n i ) / Σ(t i ) Here, i = 1, 2, 3, . . . , I, and "I" is the total number of layers made of various materials that make up the part located from the center of the active layer in the thickness direction to the center of the nanocarbon material layer in the thickness direction, etc., and "Σ" means taking the sum from i = 1 to i = I. The equivalent refractive index n eqmay be calculated based on the known refractive index and thickness of each of the constituent materials obtained by observing the cross section of the light emitting element through electron microscope observation, etc. Note that the nanocarbon material layer, etc., preferably has a band gap narrower than that of the compound semiconductor that constitutes the laminated structure, and thus the nanocarbon material layer, etc. also functions as a light absorbing material layer.

[0014] Furthermore, in the light-emitting element of the present disclosure, including the preferred embodiments described above, the thickness of the nanocarbon material layer or two-dimensional material layer constituting the second electrode is preferably, but not limited to, greater than 0 nm and less than 5 nm.

[0015] Furthermore, in the light-emitting device according to the present disclosure including the preferred embodiment described above, at least a part of the second compound semiconductor layer in the thickness direction is composed of a current injection region and a current non-injection region surrounding the current injection region, A diameter R of the current injection region at the second surface of the second compound semiconductor layer CC is, but is not limited to, 1×10 -6 m to 1×10 -2 m, preferably 2 x 10 -6 m to 1×10 -3 m. The current confinement region is defined by the current injection region. If the planar shape of the current injection region is not circular, the diameter of the circle when the circle is assumed to be equal to the area of ​​the current injection region is defined as the diameter R of the current injection region. CC Diameter R CL and diameter R CC As the relationship between 0.05R CC <R CL <0.95R CC Examples include:

[0016] Alternatively, in the light-emitting device according to the present disclosure including the preferred embodiments described above, the second compound semiconductor layer is partitioned into a first region and a second region surrounding the first region; a second electrode is provided on the first region of the second compound semiconductor layer; The second region of the second compound semiconductor layer may be configured to face the second electrode via an insulating layer.

[0017] Furthermore, in the light-emitting device of the present disclosure including the preferred embodiments and configurations described above, the second electrode may have a plurality of grooves extending in one direction (for example, a first direction) in order to control the polarization state of light emitted from the light-emitting device. Specifically, the plurality of grooves extending in the first direction are parallel to a virtual plane (XY plane described later) perpendicular to the thickness direction of the second electrode, and when the groove formation pitch P0 is significantly smaller than the wavelength λ0 of the incident light, the light vibrating in a plane parallel to the extension direction (first direction) of the grooves is selectively reflected and absorbed in the grooves. Here, the distance between the line portions of the grooves (the distance of the space portion along the second direction) is defined as the groove formation pitch P0. Then, the light (electromagnetic wave) that reaches the grooves contains a vertically polarized component and a horizontally polarized component, but the electromagnetic wave that passes through the grooves becomes linearly polarized light in which the vertically polarized component is dominant. Here, when considering the visible light wavelength band, the pitch P0 of the grooves is the effective wavelength λ of the light (electromagnetic wave) incident on the grooves. eff When the average refractive index calculated based on the material present in the space is n, the polarization component polarized in the plane parallel to the first direction is reflected or absorbed by the surface of the groove. On the other hand, when light having a polarization component polarized in the plane parallel to the second direction is incident on the groove, the electric field (light) propagating on the surface of the groove is transmitted (emitted) with the same wavelength and polarization direction as the incident wavelength from the back surface of the groove. Here, the average refractive index calculated based on the material present in the space is n ave Then, the effective wavelength λ eff is (λ0 / n ave ) is expressed by the average refractive index n ave is the sum of the product of the refractive index and the volume of the material present in the space and divided by the volume of the space. ave The smaller the value of , the greater the effective wavelength λ eff The value of n becomes larger, and therefore the value of the forming pitch P0 can be increased. ave The larger the value of , the lower the transmittance in the groove and the lower the extinction ratio.

[0018] Furthermore, in the light-emitting device of the present disclosure including the above-described preferred forms and configurations, the first light reflecting layer may have a convex shape in a direction away from the active layer, and the second light reflecting layer may have a flat shape. In this case, the radius of curvature R1 of the portion of the first light reflecting layer having a convex shape is, but is not limited to, 1×10 -5 m to 1×10 -2 m, preferably 3 x 10 -5 m to 1×10 -3 In either case, the value of R1 is the resonator length L OR is greater than the value of

[0019] Here, when the second surface of the first compound semiconductor layer is used as a reference, a first portion of the base surface (described later) on which the first light reflecting layer is formed has an upwardly convex shape. The portion of the base surface that is outside the first portion is called a second portion, and when the second surface of the first compound semiconductor layer is used as a reference, the second portion is either flat or recessed toward the second surface. The second portion of the base surface may be called a peripheral region. An extension of the first light reflecting layer may be formed on the second portion of the base surface, or the first light reflecting layer may not be formed on the second portion.

[0020] When the second portion of the base surface is recessed toward the second surface of the first compound semiconductor layer as described above, the radius of curvature R2 of the center of the second portion of the base surface is 1×10 -6 m or more, preferably 3×10 -6 m or more, preferably 5×10 -6 m or more, and when the second portion of the base surface is annular, the radius of curvature R2' of the apex of the annular convex shape of the second portion is preferably 1×10 -6 m or more, preferably 3×10 -6 m or more, preferably 5×10 -6 It is desirable that it be at least m.

[0021] When a light-emitting element array is constructed from a plurality of juxtaposed light-emitting elements, the center of the first portion of the base surface may be configured to be located on a vertex (intersection) of a square lattice, and in this case, the center of the second portion of the base surface may be configured to be located on a vertex (intersection) of the square lattice. Alternatively, the center of the first portion of the base surface may be configured to be located on a vertex (intersection) of an equilateral triangular lattice, and in this case, the center of the second portion of the base surface may be configured to be located on a vertex (intersection) of the equilateral triangular lattice.

[0022] The figure drawn by the first or second part of the base surface when the first or second part of the base surface is cut in a virtual plane (XZ plane described later) including the stacking direction of the laminated structure can be a part of a circle, a part of a parabola, a part of a sine curve, a part of an ellipse, or a part of a catenary curve. The figure may not be a part of a circle, a part of a parabola, a part of a sine curve, a part of an ellipse, or a part of a catenary curve in the strict sense. In other words, the figure may be a part of a circle, a part of a parabola, a part of a sine curve, a part of an ellipse, or a part of a catenary curve in the strict sense. The figure may be a part of a circle, a part of a parabola, a part of a sine curve, a part of an ellipse, or a part of a catenary curve in the strict sense. Some of these curves may be replaced with line segments. The figure drawn by the base surface can be obtained by measuring the shape of the base surface with a measuring instrument and analyzing the obtained data based on the least squares method.

[0023] Also, a bump may be provided on a portion of the second surface side of the second compound semiconductor layer facing the second portion of the base surface. Alternatively, a bump may be provided on a portion of the second surface side of the second compound semiconductor layer facing the center of the first portion of the base surface. Examples of the bump include a gold (Au) bump, a solder bump, and an indium (In) bump, and the bump may be provided by a known method. Specifically, the bump is provided on a second pad electrode (described later) provided on the second electrode, or on an extension of the second pad electrode.

[0024] Furthermore, in the light-emitting device of the present disclosure including the preferred embodiments and configurations described above, the cavity length L OR is, but is not limited to, 1×10 -6 m to 5×10 -4 m.

[0025] In the light-emitting device of the present disclosure including the preferred embodiments and configurations described above (hereinafter referred to as "light-emitting device of the present disclosure, etc."), the laminated structure can be made of at least one material selected from the group consisting of GaN-based compound semiconductors, InP-based compound semiconductors, and GaAs-based compound semiconductors. Specifically, the laminated structure can be made of (a) Structure made of GaN-based compound semiconductors (b) Structure made of InP-based compound semiconductors (c) Structure made of GaAs-based compound semiconductors (d) Composition consisting of GaN-based compound semiconductors and InP-based compound semiconductors (e) Composition consisting of GaN-based compound semiconductors and GaAs-based compound semiconductors (f) Composition consisting of InP-based compound semiconductors and GaAs-based compound semiconductors (g) Composition consisting of GaN-based compound semiconductors, InP-based compound semiconductors, and GaAs-based compound semiconductors Examples include:

[0026] In the light-emitting device etc. of the present disclosure, the thermal conductivity value of the laminated structure may be higher than that of the first light reflecting layer. The thermal conductivity value of the dielectric material constituting the first light reflecting layer is generally about 10 Watts / (m·K) or less. On the other hand, the thermal conductivity value of the GaN-based compound semiconductor constituting the laminated structure is about 50 Watts / (m·K) to 100 Watts / (m·K).

[0027] In the light-emitting device etc. of the present disclosure, when various compound semiconductor layers (including a compound semiconductor substrate) are present between the active layer and the first light reflecting layer, it is preferable that the materials constituting these various compound semiconductor layers (including a compound semiconductor substrate) do not have a refractive index modulation of 10% or more (there is no refractive index difference of 10% or more based on the average refractive index of the laminated structure), thereby making it possible to suppress the occurrence of disturbances in the optical field within the resonator.

[0028] The light-emitting element and the like of the present disclosure can be used to configure a surface-emitting laser element (vertical cavity laser, VCSEL) that emits laser light through a first light reflecting layer, or a surface-emitting laser element that emits laser light through a second light reflecting layer. In some cases, the substrate for manufacturing the light-emitting element (described later) may be removed.

[0029] In the light-emitting device and the like of the present disclosure, the stacked structure can be specifically configured to be made of, for example, an AlInGaN-based compound semiconductor as described above. More specifically, AlInGaN-based compound semiconductors can include GaN, AlGaN, InGaN, and AlInGaN. Furthermore, these compound semiconductors may contain boron (B) atoms, thallium (Tl) atoms, arsenic (As) atoms, phosphorus (P) atoms, and antimony (Sb) atoms as desired. The active layer desirably has a quantum well structure. Specifically, it may have a single quantum well structure (SQW structure) or a multiple quantum well structure (MQW structure). The active layer having a quantum well structure has a structure in which at least one well layer and barrier layer are stacked, and the combination of (the compound semiconductor constituting the well layer, the compound semiconductor constituting the barrier layer) is preferably (In y Ga (1-y) N,GaN), (In y Ga (1-y) N,In z Ga (1-z) N) [where y>z], (In y Ga (1-y) Examples of the semiconductor layers include GaN (GaN, AlGaN). The first compound semiconductor layer can be made of a compound semiconductor of a first conductivity type (e.g., n-type), and the second compound semiconductor layer can be made of a compound semiconductor of a second conductivity type (e.g., p-type) different from the first conductivity type. The first compound semiconductor layer and the second compound semiconductor layer are also called a first cladding layer and a second cladding layer. The first compound semiconductor layer and the second compound semiconductor layer may be layers of a single structure, layers of a multilayer structure, or layers of a superlattice structure. Furthermore, they may be layers provided with a composition gradient layer and a concentration gradient layer.

[0030] Alternatively, examples of group III atoms constituting the laminated structure include gallium (Ga), indium (In), and aluminum (Al), and examples of group V atoms constituting the laminated structure include arsenic (As), phosphorus (P), antimony (Sb), and nitrogen (N).Specific examples include AlAs, GaAs, AlGaAs, AlP, GaP, GaInP, AlInP, AlGaInP, AlAsP, GaAsP, AlGaAsP, AlInAsP, GaInAsP, AlInAs, GaInAs, AlGaInAs, AlAsSb, GaAsSb, AlGaAsSb, AlN, GaN, InN, AlGaN, GaNAs, and examples of compound semiconductors constituting the active layer include GaAs, AlGaAs, GaInAs, GaInAsP, GaInP, GaSb, GaAsSb, GaN, InN, GaInN, GaInNAs, and GaInNAsSb.

[0031] Examples of quantum well structures include a two-dimensional quantum well structure, a one-dimensional quantum well structure (quantum wire), and a zero-dimensional quantum well structure (quantum dot). Examples of materials constituting the quantum well include, but are not limited to, Si; Se; chalcopyrite compounds such as CIGS (CuInGaSe), CIS (CuInSe2), CuInS2, CuAlS2, CuAlSe2, CuGaS2, CuGaSe2, AgAlS2, AgAlSe2, AgInS2, and AgInSe2; perovskite materials; III-V compounds such as GaAs, GaP, InP, AlGaAs, InGaP, AlGaInP, InGaAsP, GaN, InAs, InGaAs, GaInNAs, GaSb, and GaAsSb; CdSe, CdSeS, CdS, CdTe, In2Se3, In2S3, Bi2Se3, Bi2S3, ZnSe, ZnTe, ZnS, HgTe, HgS, PbSe, PbS, and TiO2.

[0032] The laminated structure is formed on the second surface of the substrate for manufacturing the light-emitting element, or on the second surface of the compound semiconductor substrate. The second surface of the substrate for manufacturing the light-emitting element or the compound semiconductor substrate faces the first surface of the first compound semiconductor layer, and the first surface of the substrate for manufacturing the light-emitting element or the compound semiconductor substrate faces the second surface of the substrate for manufacturing the light-emitting element or the compound semiconductor substrate. Examples of the substrate for manufacturing the light-emitting element include a GaN substrate, a sapphire substrate, a GaAs substrate, a SiC substrate, an alumina substrate, a ZnS substrate, a ZnO substrate, an AlN substrate, a LiMgO substrate, a LiGaO2 substrate, a MgAl2O4 substrate, an InP substrate, a Si substrate, and substrates having a base layer or a buffer layer formed on the surface (main surface) of these substrates, but the use of a GaN substrate is preferable because of its low defect density. Examples of the compound semiconductor substrate include a GaN substrate, an InP substrate, and a GaAs substrate. It is known that the characteristics of a GaN substrate change between polar / non-polar / semi-polar depending on the growth surface, but any main surface (second surface) of a GaN substrate can be used to form a compound semiconductor layer. In addition, with respect to the main surface of the GaN substrate, depending on the crystal structure (e.g., cubic or hexagonal), the crystal plane orientations called the so-called A-plane, B-plane, C-plane, R-plane, M-plane, N-plane, S-plane, etc., or planes that are off in a specific direction, etc., can be used. Examples of methods for forming various compound semiconductor layers that constitute the light-emitting element include, but are not limited to, metal organic chemical vapor deposition (MOCVD, Metal Organic-Chemical Vapor Deposition, MOVPE, Metal Organic-Vapor Phase Epitaxy), molecular beam epitaxy (MBE), hydride vapor phase epitaxy (HVPE) in which halogen contributes to transport or reaction, atomic layer deposition (ALD, Atomic Layer Deposition), migration-enhanced epitaxy (MEE, Migration-Enhanced Epitaxy), and plasma-assisted physical vapor deposition (PPD).

[0033] GaAs and InP materials have the same zinc blende structure. The main surface of a compound semiconductor substrate made of these materials can be (100), (111)AB, (211)AB, (311)AB, etc., as well as a surface off in a specific direction. Note that "AB" means that the off direction is different by 90 degrees, and this off direction determines whether the main material of the surface is group III or group V. By controlling these crystal plane orientations and film formation conditions, it is possible to control the composition unevenness and dot shape. As with GaN, film formation methods such as MBE, MOCVD, MEE, and ALD are generally used, but are not limited to these methods.

[0034] Here, in forming a GaN-based compound semiconductor layer, trimethylgallium (TMG) gas or triethylgallium (TEG) gas can be used as an organic gallium source gas in the MOCVD method, and ammonia gas or hydrazine gas can be used as a nitrogen source gas. In forming a GaN-based compound semiconductor layer having an n-type conductivity, silicon (Si) can be added as an n-type impurity (n-type dopant), and in forming a GaN-based compound semiconductor layer having a p-type conductivity, magnesium (Mg) can be added as a p-type impurity (p-type dopant). When aluminum (Al) or indium (In) is included as a constituent atom of the GaN-based compound semiconductor layer, trimethylaluminum (TMA) gas can be used as an Al source, and trimethylindium (TMI) gas can be used as an In source. Furthermore, monosilane gas (SiH4 gas) may be used as the Si source, and biscyclopentadienyl magnesium gas, methylcyclopentadienyl magnesium, or biscyclopentadienyl magnesium (Cp2Mg) may be used as the Mg source. Note that examples of n-type impurities (n-type dopants) include Ge, Se, Sn, C, Te, S, O, Pd, and Po, in addition to Si, and examples of p-type impurities (p-type dopants) include Zn, Cd, Be, Ca, Ba, C, Hg, and Sr, in addition to Mg.

[0035] When the laminated structure is made of InP-based compound semiconductors or GaAs-based compound semiconductors, metalorganic raw materials such as TMGa, TEGa, TMIn, and TMAl are generally used as group III raw materials. In addition, arsine gas (AsH3 gas), phosphine gas (PH3 gas), ammonia (NH3), and the like are used as group V raw materials. In addition, metalorganic raw materials may be used as group V raw materials, such as tertiary butyl arsine (TBAs), tertiary butyl phosphine (TBP), dimethyl hydrazine (DMHy), and trimethyl antimony (TMSb). These materials decompose at low temperatures, so they are effective for low-temperature growth. As n-type dopants, monosilane (SiH4) is used as a Si source, and hydrogen selenide (H2Se) is used as a Se source. In addition, dimethyl zinc (DMZn), biscyclopentadienyl magnesium (Cp2Mg), and the like are used as p-type dopants. As dopant materials, the same materials as those of GaN are candidates.

[0036] The first surface of the first compound semiconductor layer may constitute the base surface. Alternatively, a compound semiconductor substrate (or a substrate for manufacturing a light-emitting device) may be disposed between the first surface of the first compound semiconductor layer and the first light reflecting layer, and the base surface may be constituted by the surface of the compound semiconductor substrate (or a substrate for manufacturing a light-emitting device). In this case, for example, the compound semiconductor substrate may be a GaN substrate. As the GaN substrate, any of polar substrates, semi-polar substrates, and non-polar substrates may be used. The compound semiconductor substrate may have a thickness of 5×10 -5 m to 1×10 -4 m can be exemplified, but is not limited to such a value. Alternatively, a base material is disposed between the first surface of the first compound semiconductor layer and the first light reflecting layer, or a compound semiconductor substrate and a base material are disposed between the first surface of the first compound semiconductor layer and the first light reflecting layer, and the base surface is constituted by the surface of the base material. Examples of materials constituting the base material include transparent dielectric materials such as TiO2, Ta2O5, and SiO2, silicone-based resins, and epoxy-based resins.

[0037] In the manufacture of the light-emitting element and the like of the present disclosure, the substrate for manufacturing the light-emitting element may be left as it is, or the active layer, the second compound semiconductor layer, the second electrode, and the second light reflecting layer may be formed in sequence on the first compound semiconductor layer, and then the substrate for manufacturing the light-emitting element may be removed. Specifically, the active layer, the second compound semiconductor layer, the second electrode, and the second light reflecting layer may be formed in sequence on the first compound semiconductor layer formed on the substrate for manufacturing the light-emitting element, and then the second light reflecting layer may be fixed to a support substrate, and then the substrate for manufacturing the light-emitting element may be removed to expose the first compound semiconductor layer (the first surface of the first compound semiconductor layer). The substrate for manufacturing light-emitting elements can be removed by wet etching using an alkaline aqueous solution such as a sodium hydroxide solution or a potassium hydroxide solution, an ammonia solution + hydrogen peroxide solution, a sulfuric acid solution + hydrogen peroxide solution, a hydrochloric acid solution + hydrogen peroxide solution, or a phosphoric acid solution + hydrogen peroxide solution; dry etching methods such as chemical mechanical polishing (CMP), mechanical polishing, and reactive ion etching (RIE); lift-off methods using a laser, or a combination of these.

[0038] The support substrate for fixing the second light reflecting layer may be composed of various substrates exemplified as substrates for manufacturing light emitting elements, or may be composed of an insulating substrate made of AlN or the like, a semiconductor substrate made of Si, SiC, Ge or the like, a metal substrate or an alloy substrate, but it is preferable to use a substrate having electrical conductivity, or it is preferable to use a metal substrate or an alloy substrate from the viewpoints of mechanical properties, elastic deformation, plastic deformation, heat dissipation, and the like. The thickness of the support substrate can be, for example, 0.05 mm to 1 mm. As a method for fixing the second light reflecting layer to the support substrate, known methods such as solder bonding, room temperature bonding, bonding using adhesive tape, bonding using wax bonding, and a method using an adhesive can be used, but from the viewpoint of ensuring electrical conductivity, it is preferable to adopt the solder bonding method or the room temperature bonding method. For example, when a silicon semiconductor substrate, which is a conductive substrate, is used as the support substrate, it is preferable to adopt a method that allows bonding at a low temperature of 400 ° C or less in order to suppress warping due to differences in thermal expansion coefficient. When a GaN substrate is used as the support substrate, the bonding temperature may be 400 ° C or more.

[0039] When a light-emitting element array is constructed from a plurality of light-emitting elements arranged side by side, a first electrode electrically connected to the first compound semiconductor layer may be common to the plurality of light-emitting elements, and a second electrode electrically connected to the second compound semiconductor layer may be common to the plurality of light-emitting elements, or may be provided individually for the plurality of light-emitting elements.

[0040] When the substrate for manufacturing a light-emitting element is left, the first electrode may be formed on the first surface of the substrate for manufacturing a light-emitting element, which faces the second surface of the substrate, or may be formed on the first surface of the compound semiconductor substrate, which faces the second surface of the substrate. When the substrate for manufacturing a light-emitting element is not left, the first electrode may be formed on the first surface of the first compound semiconductor layer constituting the laminated structure. In this case, since the first light reflecting layer is formed on the first surface of the first compound semiconductor layer, for example, the first electrode may be formed so as to surround the first light reflecting layer. The first electrode preferably has a single-layer or multi-layer structure containing at least one metal (including alloy) selected from the group consisting of gold (Au), silver (Ag), palladium (Pd), platinum (Pt), nickel (Ni), Ti (titanium), vanadium (V), tungsten (W), chromium (Cr), Al (aluminum), Cu (copper), Zn (zinc), tin (Sn) and indium (In). Specific examples include Ti / Au, Ti / Al, Ti / Al / Au, Ti / Pt / Au, Ni / Au, Ni / Au / Pt, Ni / Pt, Pd / Pt, and Ag / Pd. Note that the layer before the " / " in the multi-layer structure is located closer to the active layer. The same applies to the following explanation. The first electrode can be formed by a PVD method such as a vacuum deposition method or a sputtering method.

[0041] When the first electrode is formed so as to surround the first light reflecting layer, the first light reflecting layer and the first electrode may be in contact with each other. Alternatively, the first light reflecting layer and the first electrode may be spaced apart from each other. In some cases, the first electrode may be formed up to the edge of the first light reflecting layer, or the first light reflecting layer may be formed up to the edge of the first electrode.

[0042] The first layer constituting the second electrode can be made of a transparent conductive material as described above. Examples of the transparent conductive material include indium-based transparent conductive materials [specifically, for example, indium-tin oxide (ITO, indium tin oxide, Sn-doped In2O3, including crystalline ITO and amorphous ITO), indium-zinc oxide (IZO, indium zinc oxide), indium-gallium oxide (IGO), indium-doped gallium-zinc oxide (IGZO, In-GaZnO4), IFO (F-doped In2O3), ITiO (Ti-doped In2O3), InSn, InSnZnO], tin-based transparent conductive materials [specifically, for example, tin oxide (SnO X ), ATO (Sb-doped SnO2), FTO (F-doped SnO2)], zinc-based transparent conductive materials [specifically, for example, zinc oxide (including ZnO, Al-doped ZnO (AZO) and B-doped ZnO), gallium-doped zinc oxide (GZO), AlMgZnO (aluminum oxide and magnesium oxide-doped zinc oxide)], NiO, TiO X Examples of the material constituting the first layer include a transparent conductive film having a base layer of gallium oxide, titanium oxide, niobium oxide, antimony oxide, nickel oxide, etc., and a transparent conductive material such as a spinel-type oxide or an oxide having a YbFe2O4 structure. The first layer can be formed by a PVD method such as a vacuum deposition method or a sputtering method. Alternatively, a low-resistance semiconductor layer can be used as the first layer, and in this case, specifically, an n-type GaN-based compound semiconductor layer can be used. Furthermore, when the layer adjacent to the n-type GaN-based compound semiconductor layer is p-type, the electrical resistance at the interface can be reduced by joining the two via a tunnel junction.

[0043] A first pad electrode and a second pad electrode may be provided on the first electrode and the second electrode to electrically connect with an external electrode or circuit (hereinafter, sometimes referred to as "external circuit, etc."). The pad electrode preferably has a single layer structure or a multilayer structure containing at least one metal selected from the group consisting of Ti (titanium), aluminum (Al), Pt (platinum), Au (gold), Ni (nickel), and Pd (palladium). Alternatively, the pad electrode may have a multilayer structure such as a Ti / Pt / Au multilayer structure, a Ti / Au multilayer structure, a Ti / Pd / Au multilayer structure, a Ti / Pd / Au multilayer structure, a Ti / Ni / Au multilayer structure, or a Ti / Ni / Au / Cr / Au multilayer structure. When the first electrode is composed of an Ag layer or an Ag / Pd layer, it is preferable to form a cover metal layer, for example, made of Ni / TiW / Pd / TiW / Ni, on the surface of the first electrode, and to form a pad electrode, for example, made of a multilayer structure of Ti / Ni / Au or a multilayer structure of Ti / Ni / Au / Cr / Au on the cover metal layer.

[0044] The light reflecting layers (distributed Bragg reflector layers, DBR layers) constituting the first light reflecting layer and the second light reflecting layer are made of, for example, a semiconductor multilayer film or a dielectric multilayer film. Examples of the dielectric material include oxides and nitrides of Si, Mg, Al, Hf, Nb, Zr, Sc, Ta, Ga, Zn, Y, B, Ti, etc. (for example, SiN X , AlN X , AlGaN X , GaN X , B.N. X ) or fluorides. Specifically, SiO X , TiO X , NbO X , ZrO X , TaO X , ZnO X , AlO X , HfO X , SiN X , AlN XAmong these dielectric materials, two or more types of dielectric films made of dielectric materials with different refractive indices can be alternately laminated to obtain a light reflecting layer. For example, SiO X / SiN Y , SiO X / TaO X , SiO X / NbO Y , SiO X / ZrO Y , SiO X / AlN Y A multilayer film such as a SiO 2 multilayer film is preferred. In order to obtain a desired light reflectance, the material, film thickness, number of layers, and the like constituting each dielectric film may be appropriately selected. The thickness of each dielectric film can be appropriately adjusted depending on the material used, and is determined by the oscillation wavelength (light emission wavelength) λ0 and the refractive index n at the oscillation wavelength λ0 of the material used. Specifically, it is preferable to set the thickness to an odd multiple of λ0 / (4n). For example, in a light emitting device with an oscillation wavelength λ0 of 410 nm, the light reflective layer may be made of SiO X / NbO Y When the light reflecting layer is made up of, for example, a thickness of about 40 nm to 70 nm can be exemplified. The number of layers can be 2 or more, preferably about 5 to 20. The total thickness of the light reflecting layer can be, for example, about 0.6 μm to 1.7 μm. The light reflectance of the light reflecting layer is desirably 95% or more. The size and shape of the light reflecting layer are not particularly limited as long as they cover the current injection region or the element region (which will be described later).

[0045] The light reflective layer can be formed based on well-known methods, and specific examples thereof include PVD methods such as vacuum deposition, sputtering, reactive sputtering, ECR plasma sputtering, magnetron sputtering, ion beam assisted deposition, ion plating, and laser ablation; various CVD methods; coating methods such as spraying, spin coating, and dipping; methods combining two or more of these methods; and methods combining these methods with one or more of full or partial pretreatment, irradiation with inert gas (Ar, He, Xe, etc.) or plasma, irradiation with oxygen gas, ozone gas, or plasma, oxidation treatment (heat treatment), and exposure treatment.

[0046] As described above, a current injection region is provided to regulate the current injection into the active layer. Specific examples of the shape of the boundary between the current injection region and the non-current injection region and the planar shape of the opening provided in the element region and the current confinement region include a circle, an ellipse, an oval, a rectangle, and a regular polygon (equilateral triangle, square, regular hexagon, etc.). Here, the "element region" refers to a region into which a confined current is injected, or a region into which light is confined due to a refractive index difference or the like, or a region in which laser oscillation occurs within the region sandwiched between the first light reflection layer and the second light reflection layer, or a region that actually contributes to laser oscillation within the region sandwiched between the first light reflection layer and the second light reflection layer.

[0047] The nanocarbon material layer constituting the second electrode can be obtained, for example, by forming a film of these material layers on a support member, then fixing (transferring) these material layers to the second compound semiconductor layer or the first layer, and then removing the support member, or by various CVD methods, various PVD methods, liquid phase growth methods, etc., but is not limited to these methods.

[0048] Alternatively, graphene can be formed, for example, by the manufacturing method described below. That is, a film containing a graphene catalyst is formed on a support member. Then, a gas-phase carbon source is supplied to the film containing the graphene catalyst, and the gas-phase carbon source is heat-treated to generate graphene. Then, the graphene is cooled at a predetermined cooling rate, so that a film-like graphene can be formed on the film containing the graphene catalyst. Examples of the graphene catalyst include carbon compounds such as SiC, as well as at least one metal selected from Ni, Co, Fe, Pt, Au, Al, Cr, Cu, Mg, Mn, Mo, Rh, Si, Ta, Ti, W, U, V, and Zr. Examples of the gas-phase carbon source include at least one carbon source selected from carbon monoxide, methane, ethane, ethylene, ethanol, acetylene, propane, butane, butadiene, pentane, pentene, cyclopentadiene, hexane, cyclohexane, benzene, and toluene. The film-like graphene thus formed can be finally separated from the membrane containing the graphene catalyst to obtain graphene. However, the method for producing graphene is not limited thereto.

[0049] As shown in FIG. 44A, graphene is a zero-gap semiconductor in which the valence band and the conduction band have a linear dispersion relationship with respect to the Dirac point Dp, unlike ordinary semiconductors. f is at the Dirac point Dp, but it can be shifted by applying a voltage or by doping. For example, as shown in Figure 44B, the Fermi level E f For example, if you move the arrow E a As shown in the figure, 2|ΔE f Optical transitions with energies greater than | are possible. On the other hand, arrow E b As shown in the figure, 2|ΔE f Optical transitions with energies below | can be forbidden. That is, 2|ΔE f Graphene is transparent to light with energies below the Fermi level Ef By shifting the Fermi level E, it is possible to change (control) the optical transmittance for light of a desired wavelength (frequency). As shown in Figure 44C, when graphene is doped with n-type impurities, the Fermi level E f can be shifted from the Dirac point Dp to the conduction band side. On the other hand, as shown in FIG. 44D, when p-type impurities are doped into graphene, the Fermi level E f can be shifted from the Dirac point Dp to the valence band side.

[0050] In order to dope the graphene layer with n-type or p-type impurities, for example, chemical doping may be performed. To perform chemical doping, specifically, a dopant layer may be formed on the graphene layer. The dopant layer may be an electron-accepting (p-type) dopant layer, or an electron-donating (n-type) dopant layer. Materials constituting the electron-accepting (p-type) dopant layer include chlorides such as AuCl3, HAuCl4, and PtCl4; acids such as HNO3, H2SO4, HCl, and nitromethane; Group III elements such as boron and aluminum; and electron-withdrawing molecules such as oxygen. Materials constituting the electron-donating (n-type) dopant layer include Group V elements such as nitrogen and phosphorus, as well as electron-donating molecules such as pyridine-based compounds, nitrides, alkali metals, and aromatic compounds having alkyl groups.

[0051] The side surface or exposed surface of the laminated structure may be covered with a covering layer (insulating film). The covering layer (insulating film) can be formed based on a known method. The refractive index of the material constituting the covering layer (insulating film) is preferably smaller than the refractive index of the material constituting the laminated structure. The material constituting the covering layer (insulating film) is preferably SiO2-containing SiO X based materials, SiN X based materials, SiO Y N Z based materials, TaO X , ZrO X , AlN X , AlO X , GaO XExamples of the material include organic materials such as polyimide resins. Examples of the method for forming the coating layer (insulating film) include PVD methods such as vacuum deposition and sputtering, and CVD methods, and the coating layer can also be formed based on a coating method. EXAMPLES

[0052] Example 1 relates to a light-emitting device of the present disclosure. The light-emitting device of the example is composed of a surface-emitting laser element (vertical cavity laser, VCSEL) that emits laser light. A schematic partial end view of the light-emitting device of Example 1 is shown in FIG. 1. In the figure, the Z axis indicates the axis of the first light reflecting layer 41 constituting the light-emitting device (a perpendicular line passing through the center of the first light reflecting layer 41 to the laminated structure 20). The X axis is perpendicular to the Z axis, and the Y axis is perpendicular to the X axis and the Y axis.

[0053] The light emitting device 10A of Example 1 or the light emitting devices of Examples 2 to 11 described below are a first compound semiconductor layer 21 having a first surface 21a and a second surface 21b opposite to the first surface 21a; an active layer (light emitting layer) 23 facing the second surface 21b of the first compound semiconductor layer 21; and a second compound semiconductor layer 22 having a first surface 22a facing the active layer 23 and a second surface 22b opposite to the first surface 22a; A laminated structure 20 in which a first light reflecting layer 41 formed on the first surface side of the first compound semiconductor layer 21; a second light reflecting layer 42 formed on the second surface side of the second compound semiconductor layer 22; a first electrode 31 electrically connected to the first compound semiconductor layer 21; and a second electrode 32 provided between the second compound semiconductor layer 22 and the second light reflecting layer 42; Equipped with The second electrode 32 includes at least a nanocarbon material layer or a two-dimensional material layer.

[0054] The second electrode 32 specifically has a single layer of a nanocarbon material layer or a two-dimensional material layer. Alternatively, the second electrode 32 has a laminated structure of at least a first layer 32A made of a transparent conductive material or a semiconductor material (specifically, a transparent conductive material such as ITO in Example 1) and a second layer 32B made of a nanocarbon material layer or a two-dimensional material layer. In this case, the first layer 32A is in contact with the second surface 22b of the second compound semiconductor layer 22. The thickness of the nanocarbon material layer or the two-dimensional material layer constituting the second electrode 32 is not limited, but is preferably more than 0 nm and 5 nm or less. In Example 1, the nanocarbon material layer constituting the second electrode 32 specifically consists of a graphene layer.

[0055] At least a portion of the second compound semiconductor layer 22 in the thickness direction is composed of a current injection region 51 and a current non-injection region 52 surrounding the current injection region 51, The diameter R of the current injection region 51 in the second surface of the second compound semiconductor layer 22 CC is, but is not limited to, 1×10 -6 m to 1×10 -2 m, preferably 2 x 10 -6 m to 1×10 -3 m.

[0056] Furthermore, in the light emitting device 10A of Example 1, the first light reflecting layer 41 has a convex shape in a direction away from the active layer 23, and the second light reflecting layer 42 has a flat shape. The radius of curvature R1 of the portion of the first light reflecting layer 41 having a convex shape is, but is not limited to, 1×10 -5 m to 1×10 -2 m, and the cavity length L OR is, but is not limited to, 1×10 -6 m to 5×10 -4 m.

[0057] The first surface 21a of the first compound semiconductor layer 21 constitutes the base surface 90. The first light reflecting layer 41 is formed on the base surface 90. The base surface 90 has a convex shape facing away from the active layer 23. The part of the base surface 90 having the convex shape is a first portion 91, and a second portion 92 corresponding to the region between the first portion 91 and the first portion 91 is flat. Alternatively, the second portion 92 corresponding to the peripheral region of the first portion 91 is flat. The second portion 92 surrounds the first portion 91.

[0058] When the light-emitting element array is composed of a plurality of juxtaposed light-emitting elements of Example 1 or various other examples described later, the formation pitch of the light-emitting elements 10A in the light-emitting element array is desirably 3 μm or more and 50 μm or less, preferably 5 μm or more and 30 μm or less, and more preferably 8 μm or more and 25 μm or less. In addition, the radius of curvature R1 of the base surface 90 is 1×10 -4 It is preferable that the distance be equal to or larger than m. The arrangement of the light emitting elements in the light emitting element array is shown in Figs.

[0059] The laminated structure 20 may be made of at least one material selected from the group consisting of GaN-based compound semiconductors, InP-based compound semiconductors, and GaAs-based compound semiconductors.

[0060] An example of the configuration of the light emitting element 10A of the first embodiment will be described below.

[0061] The first compound semiconductor layer 21 has, for example, 2×10 16 cm -3 The active layer 23 is made of an n-GaN layer doped to a certain extent with In. 0.04 Ga 0.96 N layer (barrier layer) and In 0.16 Ga 0.84 The second compound semiconductor layer 22 has a five-layered multiple quantum well structure in which an N layer (well layer) is laminated. For example, the second compound semiconductor layer 22 has a magnesium content of 1×10 19 cm -3The first compound semiconductor layer 21 is made of a p-GaN layer doped to a certain degree. The plane orientation of the first compound semiconductor layer 21 is not limited to the {0001} plane, and may be, for example, the {20-21} plane, which is a semi-polar plane. The first electrode 31 made of Ti / Pt / Au is electrically connected to an external circuit or the like via a first pad electrode (not shown) made of, for example, Ti / Pt / Au or V / Pt / Au. On the other hand, the second electrode 32 is formed on the second compound semiconductor layer 22, and the second light reflecting layer 42 is formed on the second electrode 32. The second light reflecting layer 42 on the second electrode 32 has a flat shape. On the edge of the second electrode 32, a second pad electrode (not shown) made of, for example, Ti / Pt / Au, Ni / Pt / Au, Pd / Ti / Pt / Au, Pd / Ti / Pt / Au, Ti / Pd / Au, or Ti / Ni / Au may be formed or connected to the edge of the second electrode 32 for electrically connecting to an external circuit or the like. The first light reflecting layer 41 and the second light reflecting layer 42 are made of a laminated structure of a Ta2O5 layer and a SiO2 layer, or a laminated structure of a SiN layer and a SiO2 layer. Although the first light reflecting layer 41 and the second light reflecting layer 42 have a multi-layer structure as described above, they are shown as a single layer for the sake of simplicity of the drawings. The opening 31' provided in the first electrode 31, the first light reflecting layer 41, the second light reflecting layer 42, the opening 34A provided in the insulating layer (current confinement layer) 34, and the current injection region 51 each have a circular planar shape. The first compound semiconductor layer 21 has a first conductivity type (specifically, n-type), and the second compound semiconductor layer 22 has a second conductivity type (specifically, p-type) different from the first conductivity type.

[0062] In the laminated structure 20, a current injection region 51 and a current non-injection region 52 surrounding the current injection region 51 are formed. Here, in the example shown in FIG. 1, the current non-injection region 52 is formed in the thickness direction from the second compound semiconductor layer 22 to a part of the first compound semiconductor layer 21. However, the current non-injection region 52 may be formed in the region on the second electrode side of the second compound semiconductor layer 22 in the thickness direction, or may be formed in the entire second compound semiconductor layer 22, or may be formed in the second compound semiconductor layer 22 and the active layer 23. The current non-injection region 52 can be formed based on an ion implantation method for implanting, for example, impurities [for example, at least one type of ion (i.e., one type of ion or two or more types of ions) selected from the group consisting of boron, proton, phosphorus, arsenic, carbon, nitrogen, fluorine, oxygen, germanium, zinc, and silicon], and a current confinement region consisting of a region with reduced conductivity can be obtained.

[0063] Alternatively, as shown in FIG. 3, in order to obtain a current confinement region 52, an insulating material (e.g., SiO X and SiN X , AlO X ), and the insulating layer (current confinement layer) 34 is provided with an opening 34A for injecting a current into the second compound semiconductor layer 22. That is, the second compound semiconductor layer 22 is partitioned into a first region 22A and a second region 22B surrounding the first region 22A, a second electrode 32 is provided on the first region 22A of the second compound semiconductor layer 22, and the second region 22B of the second compound semiconductor layer 22 faces the second electrode 32 with the insulating layer 34 interposed therebetween.

[0064] Alternatively, to obtain the current confinement region, the second compound semiconductor layer 22 may be etched by the RIE method or the like to form a mesa structure, or at least a part of the laminated second compound semiconductor layer 22 may be partially oxidized laterally to form the current confinement region. Alternatively, the current confinement region may be formed by irradiating the second surface of the second compound semiconductor layer with plasma (specifically, argon, oxygen, nitrogen, or the like), or by ashing the second surface of the second compound semiconductor layer, or by reactive ion etching (RIE) processing the second surface of the second compound semiconductor layer. By irradiating the second surface of the second compound semiconductor layer with plasma, the conductivity of the second compound semiconductor layer is deteriorated, and the current non-injection region becomes in a high resistance state.

[0065] However, the second electrode 32 needs to be electrically connected to a portion of the second compound semiconductor layer 22 through which a current flows due to current confinement (current injection region).

[0066] The second electrode 32 is connected to an external circuit or the like via a second pad electrode (not shown). The first electrode 31 is also connected to an external circuit or the like via a first pad electrode (not shown). Light may be emitted to the outside via the first light reflecting layer 41, or light may be emitted to the outside via the second light reflecting layer 42.

[0067] Various specifications of the light emitting element 10A of Example 1 are shown in Tables 1, 2, 3, 4, and 5 below.

[0068] Second light reflective layer 42 SiO2 / Ta2O5 (7 pairs) Second electrode 32 Graphene (thickness: 3 atomic layers) Second compound semiconductor layer 22 p-GaN (thickness: 120 nm) Active layer 23: Multiple quantum well structure (total thickness: 30 nm) Well layer InGaN Barrier layer GaN First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Ta2O5 (15 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ0450nm Curvature radius R11mm Current injection region Formed by ion implantation of boron ions into the second compound semiconductor layer (diameter R CC :0.1mm) Substrate for manufacturing light emitting devices GaN substrate [Main surface: (0001) surface]

[0069] Second light reflective layer 42 SiO2 / Ta2O5 (7 pairs) 2nd electrode 32 Second layer: Graphene (thickness: 3 atomic layers) First layer: ITO (thickness: 5 nm) Second compound semiconductor layer 22 p-GaN (thickness: 110 nm) Active layer 23: Multiple quantum well structure (total thickness: 30 nm) Well layer InGaN Barrier layer GaN First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Ta2O5 (15 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ0450nm Curvature radius R11mm Current injection region Formed by ion implantation of boron ions into the second compound semiconductor layer (diameter R CC :0.1mm) Substrate for manufacturing light-emitting elements GaN substrate [Main surface: (20-21) surface]

[0070] Second light reflecting layer 42 SiO2 / SiN (6 pairs) 2nd electrode 32 Second layer: Boron nitride (thickness: 3 atomic layers) First layer: ITO (thickness: 5 nm) Second compound semiconductor layer 22 p-GaN (thickness: 150 nm) Active layer 23: Multiple quantum well structure (total thickness: 30 nm) Well layer InGaN Barrier layer GaN First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Ta2O5 (15 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ0525nm Curvature radius R11mm Current injection region Formed by ion implantation of boron ions into the second compound semiconductor layer (diameter R CC :0.1mm) Substrate for manufacturing light-emitting elements GaN substrate [Main surface: (20-21) surface]

[0071] Second light reflecting layer 42 SiO2 / SiN (6 pairs) 2nd electrode 32 Second layer: Molybdenum sulfide (thickness: 20 atomic layers) First layer: ITO (thickness: 5 nm) Second compound semiconductor layer 22 p-GaN (thickness: 150 nm) Active layer 23: Multiple quantum well structure (total thickness: 30 nm) Well layer InGaN Barrier layer GaN First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Nb2O5 (10 pairs) Resonator length L OR 15μm Oscillation wavelength (emission wavelength) λ0525nm Curvature radius R12mm Current injection region Formed by ion implantation of boron ions into the second compound semiconductor layer (diameter R CC :0.5mm) Substrate for manufacturing light-emitting elements GaN substrate [Main surface: (20-21) surface]

[0072] Second light reflective layer 42 SiO2 / Nb2O5 (5 pairs) Second electrode 32 Graphene (thickness: 10 atomic layers) Second compound semiconductor layer 22 p-GaN (thickness: 130 nm) Active layer 23: Multiple quantum well structure (total thickness: 15 nm) Well layer InGaN Barrier layer GaN First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / HfO2 (15 pairs) Resonator length L OR 15μm Oscillation wavelength (emission wavelength) λ0405nm Curvature radius R15mm Current injection region Formed by ion implantation of aluminum ions into the second compound semiconductor layer (diameter R CC :1mm) Substrate for manufacturing light emitting devices GaN substrate [Main surface: (0001) surface]

[0073] A method for manufacturing the light emitting device 10A of Example 1 will be outlined below.

[0074] First, after forming the stacked structure 20, the second light reflecting layer 42 is formed on the second surface side of the second compound semiconductor layer 22.

[0075] [Process-100] Specifically, on the second surface 11b of the compound semiconductor substrate 11 having a thickness of about 0.4 mm, a first compound semiconductor layer 21 having a first surface 21a and a second surface 21b opposite to the first surface 21a; an active layer (light emitting layer) 23 facing the second surface 21b of the first compound semiconductor layer 21; and a second compound semiconductor layer 22 having a first surface 22a facing the active layer 23 and a second surface 22b opposite to the first surface 22a; To form a layered structure 20 made of GaN-based compound semiconductors, a first compound semiconductor layer 21, an active layer 23, and a second compound semiconductor layer 22 are sequentially formed on the second surface 11b of the compound semiconductor substrate 11 based on an epitaxial growth method using a well-known MOCVD method, thereby obtaining the layered structure 20 (see FIG. 32A).

[0076] [Process-110] Next, a current non-injection region 52 is formed in the stacked structure 20 based on a well-known ion implantation method using boron ions (see FIG. 32B).

[0077] [Process-120] Thereafter, the second electrode 32 is formed on the second compound semiconductor layer 22. Specifically, for example, a rolled copper foil (corresponding to a support member) having a thickness of 35 μm is heated to 1000° C. in a hydrogen atmosphere (hydrogen flow rate 20 sccm) in an electric furnace, and methane gas is supplied at a flow rate of 30 sccm for 30 minutes to form a graphene layer on the copper foil. Next, an acetone diluted solution of methyl methacrylate (PMMA) is applied on the graphene layer by spin coating, and the solution is dried to form a PMMA film. Thereafter, the copper foil (support member) is removed using an aqueous iron nitrate solution, leaving the graphene layer bonded to the PMMA film. Then, the graphene layer is transferred onto the second surface 22b of the second compound semiconductor layer 22, and the PMMA film is removed using an acetone solvent. In this manner, the second electrode 32 made of the graphene layer can be obtained on the second surface 22b of the second compound semiconductor layer 22. Furthermore, if desired, a second pad electrode is formed on the second electrode 32 based on a combination of a film formation method such as a sputtering method or a vacuum deposition method and a patterning method such as a wet etching method or a dry etching method.

[0078] [Process-130] Next, the second light reflecting layer 42 is formed on the second electrode 32. Specifically, the second light reflecting layer 42 is formed from above the second electrode 32 to above the second pad electrode based on a combination of a film forming method such as a sputtering method or a vacuum deposition method and a patterning method such as a wet etching method or a dry etching method. The second light reflecting layer 42 on the second electrode 32 has a flat shape. In this manner, the structure shown in FIG. 33 is obtained.

[0079] [Process-140] Next, the second light reflecting layer 42 is fixed to a support substrate 49 via a bonding layer 48 (see FIG. 34). Specifically, the second light reflecting layer 42 is fixed to a support substrate 49 made of a sapphire substrate using a bonding layer 48 made of an adhesive.

[0080] [Process-150] Next, the compound semiconductor substrate 11 is thinned by mechanical polishing or CMP, and further, the compound semiconductor substrate 11 is removed by etching.

[0081] [Process-160] Thereafter, a sacrificial layer 81 is formed on a region of the base surface 90 (specifically, the first surface 21a of the first compound semiconductor layer 21) where the first light reflecting layer 41 is to be formed, and then the surface of the sacrificial layer 81 is made convex. Specifically, a resist material layer is formed on the first surface 21a of the first compound semiconductor layer 21, and the resist material layer is patterned so as to remain on the region of the base surface 90 where the first portion 91 is to be formed (see FIG. 35A), and then the remaining resist material layer is subjected to a heat treatment, thereby obtaining a sacrificial layer 81' having a convex surface (see FIG. 35B). Next, the sacrificial layer 81' is etched back, and further etched back from the base surface 90 toward the inside (i.e., from the first surface 21a of the first compound semiconductor layer 21 toward the inside of the first compound semiconductor layer 21), so that a convex portion can be formed in the first portion 91 of the base surface 90 when the second surface 21b of the first compound semiconductor layer 21 is used as a reference (see FIG. 35C). A second portion 92 corresponding to a region between the first portion 91 of the base surface 90 is flat. The etch back can be performed based on a dry etching method such as an RIE method, or based on a wet etching method using hydrochloric acid, nitric acid, hydrofluoric acid, phosphoric acid, a mixture thereof, or the like. Note that in FIGS. 35A, 35B, and 35C, illustrations of the active layer, the second compound semiconductor layer, the second light reflecting layer, and the like are omitted.

[0082] [Process-170] Next, the first light reflecting layer 41 is formed on the convex portion 91 of the base surface 90. Specifically, the first light reflecting layer 41 is formed on the entire surface of the base surface 90 based on a film forming method such as a sputtering method or a vacuum deposition method, and then the first light reflecting layer 41 is patterned to obtain the first light reflecting layer 41 on the convex portion 91 of the base surface 90. Then, the first electrode 31 is formed on the area of ​​the base surface 90 where the first light reflecting layer 41 is not formed. In this manner, the light emitting element 10A of the first embodiment shown in FIG. 1 can be obtained. If the first electrode 31 is made to protrude from the first light reflecting layer 41, the first light reflecting layer 41 can be protected. Then, it is sufficient to electrically connect it to an external electrode or circuit (a circuit that drives the light emitting element). Specifically, the first compound semiconductor layer 21 is connected to an external circuit or the like via the first electrode 31 and a first pad electrode (not shown), and the second compound semiconductor layer 22 is connected to an external circuit or the like via the second electrode 32 and a second pad electrode. Next, the light emitting device 10A of the first embodiment is completed by packaging and sealing.

[0083] 2 is a schematic partial end view of Modification 1 of the light-emitting element 10A of Example 1, in [Step 120], a second electrode 32 having a laminated structure of a first layer 32A made of a transparent conductive material such as ITO and a second layer 32B made of a nanocarbon material layer or the like may be formed on the second surface 22b of the second compound semiconductor layer 22. In this case, the first layer 32A is in contact with the second compound semiconductor layer 22.

[0084] In order to control the polarization state of light emitted from the light-emitting element 10A, the second electrode 32, more specifically, the second electrode 32 composed of a first layer and a second layer, may have a plurality of grooves formed in the second layer extending in one direction (e.g., a first direction, Y direction).

[0085] In addition, in order to obtain a current non-injection region 52, an insulating material (e.g., SiO X and SiN X , AlO X), and the insulating layer (current confinement layer) 34 is provided with an opening 34A for injecting a current into the second compound semiconductor layer 22. FIG. 3 shows a schematic partial end view of Modification 2 of the light-emitting element 10A having such a structure. The insulating layer 34 having the opening 34A defines a current confinement region (current non-injection region 52). That is, the opening 34A defines a current injection region 51.

[0086] In the light-emitting device of Example 1, since the second electrode has a nanocarbon material layer or the like, the resistance of the second electrode as a whole can be reduced, current can be made to flow uniformly in the active layer, and the occurrence of a non-uniform state of current flowing from the periphery to the center of the second electrode can be suppressed. Therefore, the occurrence of problems such as a shortage of current flowing in the center of the current injection region, inhibition of oscillation, and an increase in threshold current can be suppressed, and oscillation at a lower threshold current is possible. In addition, it is possible to prevent the oscillation in the transverse mode from becoming unstable. As a result of the above, the area of ​​the active layer (light-emitting layer) can be expanded, and a light-emitting device with a large light output can be provided.

[0087] In addition, in the light-emitting device of Example 1, the first light reflecting layer functions as a concave mirror, so that the light diffracts and spreads from the active layer as a starting point, and the light incident on the first light reflecting layer can be reliably reflected toward the active layer and focused on the active layer. Therefore, it is possible to avoid an increase in diffraction loss, and laser oscillation can be reliably performed, and the problem of thermal saturation can be avoided because of the long resonator. In addition, since the resonator length can be made long, the tolerance of the manufacturing process of the light-emitting device is increased, and the yield can be improved. Incidentally, the "diffraction loss" generally refers to a phenomenon in which the laser light traveling back and forth through the resonator gradually dissipates outside the resonator because the light tends to spread due to the diffraction effect.

[0088] In addition, in the manufacturing process of the light-emitting element, a GaN substrate is used, but a GaN-based compound semiconductor is not formed based on a method of lateral epitaxial growth such as the ELO method. Therefore, as the GaN substrate, not only a polar GaN substrate but also a semi-polar GaN substrate or a non-polar GaN substrate can be used. When a polar GaN substrate is used, the light-emitting efficiency tends to decrease due to the effect of the piezoelectric field in the active layer, but the use of a non-polar GaN substrate or a semi-polar GaN substrate can solve or mitigate such a problem.

[0089] As shown in FIG. 4, a schematic partial end view of the modified example-3 of the light emitting element 10A of the first embodiment is a laminated structure of the first layer 32A and the second layer 32B, and the second layer 32B is not formed in the center of the second electrode 32, which can suppress the emission of light in a higher mode from the light emitting element 10A. A transparent thin film (flattening film) 32C made of ITO may be formed in the region of the second electrode 32 where the second layer 32B is not formed in the center. The light generated in the active layer 23 and passing through the transparent thin film 32C is not absorbed in the transparent thin film 32C. On the other hand, the second layer 32B surrounding the transparent thin film 32C absorbs the light generated in the active layer 23. Specifically, in such a light emitting element 10A, the distance L2 from the center of the active layer 23 in the thickness direction of the laminated structure 20 to the center of the second layer 32B in the thickness direction does not satisfy the above-mentioned formula (A). As a result, the second layer 32B is not located in the minimum amplitude portion of the light intensity distribution, and the second layer 32B easily absorbs the light generated in the active layer 23. That is, light having a higher-order transverse mode is easily absorbed by the second layer 32B, while light having a first-order transverse mode passes through the transparent thin film 32C, making it possible to control the transverse mode laser light emitted from the light-emitting element 10A. In this way, it is possible to accurately control the oscillation wavelength of the laser light emitted from the surface-emitting laser element, and the light-emitting efficiency of the light-emitting element 10A can be improved. The diameter R of the area in the center of the second electrode 32 where the second layer 32B is not formed is CL and diameter R CC As the relationship between 0.05RCC <R CL <0.95R CC The specifications of such a light-emitting device are shown in Table 5. However, the second electrode 32 [graphene (thickness: 10 atomic layers)] is a doughnut-shaped second electrode 32 with a diameter of about 100 μm removed from the center. That is, the diameter R CL = 100 μm. Alternatively, the specifications of such a light-emitting device are shown in Table 6 (described later).

[0090] On the other hand, in any of the specifications shown in Tables 1 to 5, in the light emitting element 10A, the distance L2 from the center of the active layer 23 in the thickness direction of the laminated structure 20 to the center of the nanocarbon material layer, etc. in the thickness direction satisfies the above-mentioned formula (A). This makes it possible to position the nanocarbon material layer, etc. constituting the second electrode 32 in the minimum amplitude part of the light intensity distribution, that is, to position the nanocarbon material layer, etc. in the minimum amplitude part generated in the standing wave of light formed inside the light emitting element 10A, so that the nanocarbon material layer, etc. constituting the second electrode 32 is less likely to absorb the light generated in the active layer 23, and the light emission efficiency of the light emitting element 10A can be improved, and the oscillation wavelength of the laser light emitted from the surface emitting laser element can be accurately controlled. The optical absorption coefficient of the nanocarbon material layer is more than twice the optical absorption coefficient of the second compound semiconductor layer 22 made of a p-GaN layer, specifically, about 1×10 3 The active layer 23 is located at a maximum amplitude portion of the standing wave of light formed inside the light emitting element 10A.

[0091] When a plurality of longitudinal modes occur in the gain spectrum determined by the active layer 23, this is shown in FIG. 45. In FIG. 45, two longitudinal modes, longitudinal mode A and longitudinal mode B, are illustrated. In this case, the light absorbing material layer 26 is located in the minimum amplitude portion of the longitudinal mode A and is not located in the minimum amplitude portion of the longitudinal mode B. In this case, the mode loss of the longitudinal mode A is minimized, but the mode loss of the longitudinal mode B is large. In FIG. 45, the mode loss of the longitudinal mode B is shown by a solid line. Therefore, the longitudinal mode A is easier to oscillate than the longitudinal mode B. Therefore, by using such a structure, that is, by controlling the position of the light absorbing material layer 26, a specific longitudinal mode can be stabilized and made easier to oscillate. On the other hand, the mode loss for the undesired other longitudinal modes can be increased, so that the oscillation of the undesired other longitudinal modes can be suppressed.

[0092] Therefore, by controlling the position of the nano-carbon material layer or the like functioning as the light absorbing material layer 26 in this manner, it is possible to suppress the oscillation of laser light of an undesired longitudinal mode among the laser light of multiple longitudinal modes that can be emitted from the surface emitting laser element, and as a result, it becomes possible to accurately control the oscillation wavelength of the emitted laser light.

[0093] For example, at least two layers, preferably at least four layers, of the light absorbing material layer 26 described above may be arranged so as to satisfy formula (A) of the first compound semiconductor layer 21. That is, it is preferable that the light absorbing material layer 26 is located in a minimum amplitude portion of the standing wave of light formed inside the laminated structure 20. The thickness of the light absorbing material layer 26 is preferably λ0 / (4·n eq ) or less. The lower limit of the thickness of the light absorbing material layer 26 can be, for example, 1 nm. It is preferable that the light absorbing material layer 26 has a light absorption coefficient that is at least twice as high as the light absorption coefficient of the compound semiconductor that constitutes the stacked structure 20.

[0094] The light absorbing material layer 26 may be configured to be composed of at least one material selected from the group consisting of compound semiconductor materials, impurity-doped compound semiconductor materials, transparent conductive materials, and light reflecting layer constituent materials having light absorbing properties. Here, for example, when the compound semiconductor constituting the laminated structure 20 is GaN, an example of a compound semiconductor material having a narrower band gap than the compound semiconductor constituting the laminated structure 20 is InGaN, and for example, an impurity-doped compound semiconductor material is Si-doped n-GaN or B-doped n-GaN, and for example, a light reflecting layer constituent material having light absorbing properties is a material constituting the light reflecting layer (for example, SiO X , SiN X , TaO X The light absorbing material layers 26 may all be made of one of these materials. Alternatively, each of the light absorbing material layers 26 may be made of various materials selected from these materials, but it is preferable that one light absorbing material layer 26 is made of one material from the viewpoint of simplifying the formation of the light absorbing material layer 26. The light absorbing material layer 26 may be formed in the first compound semiconductor layer 21, may be formed in the second compound semiconductor layer 22, may be formed in the first light reflecting layer 41, may be formed in the second light reflecting layer 42, or may be any combination of these. A schematic partial end view of a light emitting device (Modification-4 of Example 1) in which one light absorbing material layer 26 is formed in the first compound semiconductor layer 21 is shown in FIG. 5.

[0095] The light emitting device of the above-mentioned Example 1 or various modifications can be applied to the light emitting devices of Examples 2 and 3. EXAMPLES

[0096] Example 2 is a modification of Example 1. In Example 1, the stacked structure 20 is made of a GaN-based compound semiconductor. On the other hand, in Example 2, the stacked structure 20 is made of an InP-based compound semiconductor. Specifically, the first compound semiconductor layer 21 is made of Se at 1×10 18 cm-3 The active layer 23 is made of an AlGaInAs layer, and the second compound semiconductor layer 22 is made of 1×10 19 cm -3 The current non-injection region 52 is formed of a stacked structure of n-AlGaInAs layer / p-AlGaInAs layer / n-InP layer, or an Fe-doped InP layer, or is formed based on an ion implantation method. The configuration of the second electrode 32 is the same as that described in the first embodiment. Furthermore, in the light-emitting device of the second embodiment, which is a modified example of the second embodiment, the first light reflection layer 41 is formed on a semi-insulating InP substrate (undoped or doped with Fe) as a substrate for manufacturing the light-emitting device. Except for the above points, the light-emitting device of the second embodiment can have the same configuration and structure as the light-emitting device of the first embodiment, so a detailed description will be omitted.

[0097] The specifications of the light-emitting device of Example 2 are shown in Table 6 below.

[0098] Second light reflective layer 42 SiO2 / Ta2O5 (7 pairs) Second electrode 32 Graphene (thickness: 3 atomic layers) Second compound semiconductor layer 22 p-InP (thickness: 200 nm) Active layer 23: Multiple quantum well structure (total thickness: 40 nm) Well layer AlGaInAs Barrier layer AlGaInAs First compound semiconductor layer 21 n-InP First light reflecting layer 41 SiO2 / Ta2O5 (15 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ01400nm Curvature radius R11mm Current injection region Formed by ion implantation of hydrogen ions into the second compound semiconductor layer (diameter R CC :0.1mm) Substrate for manufacturing light emitting devices InP substrate

[0099] Alternatively, in Example 2, the laminated structure 20 can be made of a GaAs-based compound semiconductor. The specifications of such a modified example of the light-emitting device in Example 2 are shown in Table 7 below.

[0100] Second light reflective layer 42 SiO2 / Ta2O5 (7 pairs) Second electrode 32 Graphene (thickness: 3 atomic layers) Second compound semiconductor layer 22 p-AlGaAs (thickness: 200 nm) Active layer 23: Multiple quantum well structure (total thickness: 40 nm) Well layer InGaAs Barrier layer AlGaAs First compound semiconductor layer 21 n-AlGaAs First light reflecting layer 41 SiO2 / Ta2O5 (15 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ0 approx. 900 nm Curvature radius R11mm Current injection region Formed by ion implantation of hydrogen ions into the second compound semiconductor layer (diameter R CC :0.1mm) Substrate for manufacturing light emitting devices GaAs substrate EXAMPLES

[0101] Example 3 is a modification of Examples 1 and 2. In a light-emitting device 10B of Example 3, a schematic partial end view of which is shown in Fig. 6, a compound semiconductor substrate 11 is disposed (remained) between a first surface 21a of a first compound semiconductor layer 21 and a first light reflecting layer 41, and a base surface 90 is formed of a surface (first surface 11a) of the compound semiconductor substrate 11. Note that Fig. 6 illustrates a light-emitting device based on the light-emitting device of Modification 2 of Example 1, but the present invention is not limited thereto.

[0102] In the light emitting device 10B of Example 3, the compound semiconductor substrate 11 is thinned and mirror-finished in the same process as [Step-150] of Example 1. The surface roughness Ra of the first surface 11a of the compound semiconductor substrate 11 is preferably 10 nm or less. The surface roughness Ra is specified in JIS B-610:2001, and specifically, can be measured based on observation using AFM or cross-sectional TEM. Thereafter, a sacrificial layer in [Step-160] of Example 1 is formed on the exposed surface (first surface 11a) of the compound semiconductor substrate 11, and the same processes as those after [Step-160] of Example 1 are performed, and a base surface 90 consisting of a first portion 91 and a second portion 92 is provided on the compound semiconductor substrate 11 instead of the first compound semiconductor layer 21 in Example 1, thereby completing the light emitting device. The first electrode 31 may be formed on the compound semiconductor substrate 11.

[0103] Except for the above points, the configuration and structure of the light-emitting element of Example 3 can be similar to the configurations and structures of the light-emitting elements of Examples 1 and 2, and therefore a detailed description thereof will be omitted.

[0104] Alternatively, the first light reflecting layer 41 may be formed on a sapphire substrate as a substrate for manufacturing a light emitting device. In this case, the first electrode 31 may be connected to the first compound semiconductor layer 21 in a region not shown. EXAMPLES

[0105] Example 4 is also a modification of Examples 1 and 2. In a light-emitting device 10C of Example 4, the schematic partial end view of which is shown in FIG. 7, a base material 95 is disposed between the first surface 21a of the first compound semiconductor layer 21 and the first light reflecting layer 41, and the base surface 90 is constituted by the surface of the base material 95. Alternatively, in a modification of the light-emitting device 10C of Example 4, the schematic partial end view of which is shown in FIG. 8, a compound semiconductor substrate 11 and a base material 95 are disposed between the first surface 21a of the first compound semiconductor layer 21 and the first light reflecting layer 41, and the base surface 90 is constituted by the surface of the base material 95. Examples of materials constituting the base material 95 include transparent dielectric materials such as TiO2, Ta2O5, and SiO2, silicone-based resins, and epoxy-based resins. Note that, although FIGS. 7 and 8 show a light-emitting device based on the light-emitting device of Modification-2 of Example 1, the present invention is not limited thereto.

[0106] In the light-emitting device 10C of Example 4 shown in FIG. 7, the compound semiconductor substrate 11 is removed in a step similar to [Step-150] of Example 1, and a base material 95 having a base surface 90 is formed on the first surface 21a of the first compound semiconductor layer 21. Specifically, for example, a TiO2 layer or a Ta2O5 layer is formed on the first surface 21a of the first compound semiconductor layer 21, and then a patterned resist layer is formed on the TiO2 layer or Ta2O5 layer on which the first portion 91 is to be formed, and the resist layer is heated to reflow the resist layer, thereby obtaining a resist pattern. The resist pattern is given a shape that is the same as (or a similar shape to) the shape of the first portion. Then, the resist pattern and the TiO2 layer or the Ta2O5 layer are etched back, whereby a base material 95 (made of a TiO2 layer or a Ta2O5 layer) on which the first portion 91 and the second portion 92 are provided can be obtained on the first surface 21a of the first compound semiconductor layer 21. Next, the first light reflecting layer 41 may be formed on the desired area of ​​the substrate 95 based on a known method.

[0107] Alternatively, in the light-emitting device 10C of Example 4 shown in FIG. 8, the compound semiconductor substrate 11 is thinned and mirror-finished in the same process as [Step-150] of Example 1, and then a base material 95 having a base surface 90 is formed on the exposed surface (first surface 11a) of the compound semiconductor substrate 11. Specifically, for example, a TiO2 layer or a Ta2O5 layer is formed on the exposed surface (first surface 11a) of the compound semiconductor substrate 11, and then a patterned resist layer is formed on the TiO2 layer or Ta2O5 layer on which the first portion 91 is to be formed, and the resist layer is heated to reflow the resist layer, thereby obtaining a resist pattern. The resist pattern is given the same shape (or a similar shape) as the shape of the first portion. Then, the resist pattern and the TiO2 layer or the Ta2O5 layer are etched back, whereby a base material 95 (made of a TiO2 layer or a Ta2O5 layer) on which the first portion 91 and the second portion 92 are provided can be obtained on the exposed surface (first surface 11a) of the compound semiconductor substrate 11. Next, the first light reflecting layer 41 may be formed on the desired area of ​​the substrate 95 based on a known method.

[0108] Except for the above points, the configuration and structure of the light-emitting element of Example 4 can be similar to the configurations and structures of the light-emitting elements of Examples 1 and 2, and therefore a detailed description thereof will be omitted. EXAMPLES

[0109] Incidentally, in the light-emitting elements described in Examples 1 to 4, for example, if a strong external force is applied to the rising portion of first portion 91 of flat base surface 90 for some reason, stress will be concentrated in the rising portion of first portion 91, and there is a risk of damage being caused to the first compound semiconductor layer, etc.

[0110] Example 5 is a modification of Examples 1 to 4. Fig. 9 shows a schematic partial end view of a light emitting element 10D of Example 5, and Fig. 10 shows a schematic partial end view of a light emitting element array including a plurality of light emitting elements 10D of Example 5. Also, Figs. 35A, 35B, 36A, 36B, 36C, 37A, 37B, 37C, 38A, and 38B show schematic partial end views of a first compound semiconductor layer and the like for explaining a manufacturing method of the light emitting element of Example 5.

[0111] In addition, in Figures 36A, 36B, 36C, 37A, 37B, 37C, 38A, 38B, 39A, 39B, 40A, 40B, 41A, 41B, 42A, 42B, and 42C, the active layer, the second compound semiconductor layer, the second light reflecting layer, etc. are omitted. In addition, in Figures 11, 12, 15, 16, 17, 18, 21, and 22, the first portion of the base surface is shown by a solid circle or ellipse for clarity, the center of the second portion of the base surface is shown by a solid circle for clarity, and the top portion of the annular convex shape of the second portion of the base surface is shown by a solid ring for clarity.

[0112] In the light-emitting device 10D of Example 5, the first light-reflecting layer 41 is A base surface 90 located on the first surface side of the first compound semiconductor layer 21 is composed of a first portion 91 and a second portion 92 (peripheral region 99) surrounding the first portion 91, The first light reflecting layer 41 is formed on the first portion 91, With respect to the second surface 21b of the first compound semiconductor layer 21 as a reference, the first portion 91 is convex and the second portion 92 is concave, and differentiable from the first portion 91 to the second portion 92. The light-emitting device 10D shown in Figs. 9 and 10 is a light-emitting device to which Modification 2 of Example 1 is applied.

[0113] Here, when the base surface 90 is expressed as z=f(x, y), the differential value at the base surface 90 is ∂z / ∂x=[∂f(x,y) / ∂x] y ∂z / ∂y=[∂f(x,y) / ∂y] x It can be obtained. "Smooth" is a term in analysis. For example, if a real variable function f(x) is differentiable at a < x < b and f'(x) is continuous, it can be said to be continuously differentiable in a catchphrase, and it can also be expressed as smooth. And the part where an inflection point exists on the base surface 90 extending from the first part 91 to the second part 92 is the boundary between the first part 91 and the second part 92.

[0114] As described above, when taking the second surface 21b of the first compound semiconductor layer 21 as a reference, the second part 92 of the base surface 90 occupying the peripheral region 99 has a downwardly convex shape. The light-emitting element having such a configuration is called the 'light-emitting element of the first A configuration'. And in a light-emitting element array including a plurality of light-emitting elements of the first A configuration, the central part of the first part 91 of the base surface 90 can be configured to be located on the vertex (intersection) of a square lattice, or alternatively, the central part of the first part 91 of the base surface 90 can be configured to be located on the vertex (intersection) of an equilateral triangle lattice. In the former case, the central part of the second part 92 of the base surface 90 can be configured to be located on the vertex (intersection) of a square lattice, and in the latter case, the central part of the second part 92 of the base surface 90 can be configured to be located on the vertex (intersection) of an equilateral triangle lattice.

[0115] In the light-emitting element of the first A configuration, the shape from [the peripheral part to the central part of the first part / the second part] is (A) [upwardly convex shape / downwardly convex shape] (B) [upwardly convex shape / continuing to a line segment from the downwardly convex shape] (C) [upwardly convex shape / continuing from the upwardly convex shape to the downwardly convex shape] (D) [upwardly convex shape / continuing from the upwardly convex shape to the downwardly convex shape and then to a line segment] (E) [upwardly convex shape / continuing from a line segment to the downwardly convex shape] (F) [upwardly convex shape / continuing from a line segment to the downwardly convex shape and then to a line segment] In the light-emitting element, the base surface may terminate at the center of the second portion. In the light-emitting element 10D of Example 5, the shape of [the first portion 91 / second portion 92 from the periphery to the center] specifically corresponds to the case (A).

[0116] Alternatively, when the second surface 21b of the first compound semiconductor layer 21 is used as a reference, the second portion 92 of the base surface 90 occupying the peripheral region 99 can be configured to have a downwardly convex shape toward the center of the peripheral region 99 and an upwardly convex shape extending from the downwardly convex shape. A light-emitting element having such a configuration is referred to as a "light-emitting element of configuration B." In the light-emitting element of configuration B, when the distance from the second surface 21b of the first compound semiconductor layer 21 to the center of the first portion 91 of the base surface 90 is LL1 and the distance from the second surface 21b of the first compound semiconductor layer 21 to the center of the second portion 92 of the base surface 90 is LL2, LL2>LL1 In addition, when the radius of curvature of the center of the first portion 91 of the base surface 90 (i.e., the radius of curvature of the first light reflecting layer) is R1, and the radius of curvature of the center of the second portion 92 of the base surface 90 is R2, R1>R2 The value of LL2 / LL1 is not limited to the following, but may be: 1 <LL2 / LL1≦100 The value of R1 / R2 can be, but is not limited to, 1 <R1 / R2≦100 Examples include:

[0117] In the light-emitting element of the Bth configuration, the shape of [the first portion 91 / the second portion 92 from the peripheral portion to the center portion] is (A) [Upward convex shape / downward convex shape followed by upward convex shape] (B) [Upward convex shape / upward convex shape continues to downward convex shape to upward convex shape] (C) [Upward convex shape / line segment leads to downward convex shape, then to upward convex shape] There are cases like this.

[0118] Alternatively, when the second surface 21b of the first compound semiconductor layer 21 is used as a reference, the second portion 92 of the base surface 90 occupying the peripheral region 99 can be configured to have an annular convex shape surrounding the first portion 91 of the base surface 90, and a downwardly convex shape extending from the annular convex shape toward the first portion 91 of the base surface 90. A light-emitting element having such a configuration will be referred to as a “light-emitting element of configuration C.”

[0119] In the light-emitting device of configuration C, when the distance from the second surface 21b of the first compound semiconductor layer 21 to the center of the first portion 91 of the base surface 90 is defined as LL1 and the distance from the second surface 21b of the first compound semiconductor layer 21 to the top of the annular convex shape of the second portion 92 of the base surface 90 is defined as LL2', LL2'>LL1 In addition, when the radius of curvature of the center of the first portion 91 of the base surface 90 (i.e., the radius of curvature of the first light reflecting layer) is R1, and the radius of curvature of the apex of the annular convex shape of the second portion 92 of the base surface 90 is R2', R1>R2' The value of LL2' / LL1 is not limited to the following, but may be: 1 <LL2’ / LL1≦100 Examples of the value of R1 / R2' include, but are not limited to, 1 <R1 / R2’≦100 The following can be mentioned.

[0120] In the light-emitting element of the Cth configuration, the shape of [the first portion 91 / the second portion 92 from the peripheral portion to the center portion] is (A) [From an upward convex shape / downward convex shape to an upward convex shape / downward convex shape] (B) [From an upwardly convex shape / downwardly convex shape to an upwardly convex shape, a downwardly convex shape, and a line segment] (C) [Upward convex shape / upward convex shape followed by downward convex shape, upward convex shape, downward convex shape] (D) [Upwardly convex shape / upwardly convex shape to downwardly convex shape to upwardly convex shape to downwardly convex shape, followed by a line segment] (E) [Upward convex shape / line segment leading to downward convex shape, upward convex shape, downward convex shape] (F) [Upward convex shape / line segment followed by downward convex shape, upward convex shape, downward convex shape, line segment] In addition, in the light emitting element, the base surface 90 may terminate at the center of the second portion 92.

[0121] In the light-emitting device of the B configuration or the C configuration including the preferred configuration described above, a bump may be provided on the second surface side of the second compound semiconductor layer facing the convex portion of the second portion of the base surface. Alternatively, in the light-emitting device of the A configuration including the preferred configuration described above, a bump may be provided on the second surface side of the second compound semiconductor layer facing the center of the first portion of the base surface. Examples of the bump include a gold (Au) bump, a solder bump, and an indium (In) bump, and the bump may be provided by a known method. Specifically, the bump is provided on a second pad electrode provided on the second electrode, or on an extension of the second pad electrode.

[0122] The light-emitting device 10D of Example 5 will be specifically described below.

[0123] In the light emitting device 10D of Example 5, the base surface 90 of the light emitting devices 10A, 10B, and 10C described in Examples 1 to 4 extends to the peripheral region 99, and the base surface 90 is uneven and differentiable. That is, in the light emitting device 10D of Example 5, the base surface 90 is analytically smooth. Note that, like the light emitting devices 10A, 10B, and 10C described in Examples 1 to 4, the first light reflecting layer 41 is formed on the base surface 90 located on the first surface side of the first compound semiconductor layer 21, and the second light reflecting layer 42 is formed on the second surface side of the second compound semiconductor layer 22 and has a flat shape.

[0124] When the second surface 21b of the first compound semiconductor layer 21 is taken as a reference, the first portion 91 of the base surface 90 on which the first light reflecting layer 41 is formed has an upwardly convex shape, and when the second surface 21b of the first compound semiconductor layer 21 is taken as a reference, the second portion 92 of the base surface 90 occupying the peripheral region 99 has a downwardly convex shape and surrounds the first portion 91. c are located on the vertices (intersections) of a square grid (see FIG. 11 for an arrangement state, for example), or alternatively, the central portion 91 of the first portion 91 of the base surface 90 c are located on the vertices (intersections) of a lattice of equilateral triangles (see FIG. 12 for an example of the arrangement).

[0125] The first light reflecting layer 41 is formed on a first portion 91 of the base surface 90, but an extension of the first light reflecting layer 41 may be formed on a second portion 92 of the base surface 90 occupying the peripheral region 99, or the first light reflecting layer 41 may not be formed on the second portion 92. In Example 5, the first light reflecting layer 41 is not formed on the second portion 92 of the base surface 90 occupying the peripheral region 99.

[0126] In the light-emitting element 10D of Example 5, the boundary 90 between the first portion 91 and the second portion 92 bd teeth, (1) When the first light reflecting layer 41 does not extend to the peripheral region 99, the outer periphery of the first light reflecting layer 41 (2) When the first light reflecting layer 41 extends into the peripheral region 99, a portion where an inflection point exists on the base surface 90 from the first portion 91 to the second portion 92 Here, the light-emitting element 10D of Example 5 specifically corresponds to case (1).

[0127] In the light-emitting device 10D of Example 5, the first surface 21a of the first compound semiconductor layer 21 constitutes the base surface 90. The figure drawn by the first portion 91 of the base surface 90 when the base surface 90 is cut by a virtual plane (for example, the XZ plane in the illustrated example) including the stacking direction of the stacked structure 20 is differentiable, and more specifically, it can be a part of a circle, a part of a parabola, a part of a sine curve, a part of an ellipse, or a part of a catenary curve, or a combination of these curves, and a part of these curves may be replaced with a line segment. The figure drawn by the second portion 92 is also differentiable, and more specifically, it can be a part of a circle, a part of a parabola, a part of a sine curve, a part of an ellipse, or a part of a catenary curve, or a combination of these curves, and a part of these curves may be replaced with a line segment. Furthermore, the boundary between the first portion 91 and the second portion 92 of the base surface 90 is also differentiable.

[0128] In the light-emitting element array, the formation pitch of the light-emitting elements is desirably 3 μm or more and 50 μm or less, preferably 5 μm or more and 30 μm or less, and more preferably 8 μm or more and 25 μm or less. c The radius of curvature R1 is 1×10 -4 The resonator length L OR is 1 x 10 -6 m≦L OR In the light-emitting element array of Example 5, the arrangement of which is shown in Fig. 11 and Fig. 12, the parameters of the light-emitting element 10D are shown in Table 8 below. Note that the diameter of the first light reflecting layer 41 is indicated as D1, the height of the first portion 91 is indicated as H1, and the center 92 of the second portion 92 of the base surface 90 is indicated as H2. c The radius of curvature of the first portion 91 is indicated by R2. Here, the height H1 of the first portion 91 is the distance from the second surface 21b of the first compound semiconductor layer 21 to the center 91 of the base surface 90. c LL1 is a distance from the second surface 21b of the first compound semiconductor layer 21 to the center 92 of the second portion 92 of the base surface 90. c When the distance to is LL2, H1=LL1-LL2 The specifications of the light-emitting element 10D of Example 5, the arrangement of which is shown in Fig. 11 and Fig. 12, are shown in the following Tables 9 and 10. Note that the "number of light-emitting elements" refers to the number of light-emitting elements constituting one light-emitting element array.

[0129] See the layout in Figure 11. See the layout in Figure 12. Formation pitch 25μm 20μm Radius of curvature R1100μm 200μm Diameter D120μm 15μm Height H12μm 2μm Radius of curvature R22μm 3μm

[0130] Table 9: See the layout in Figure 11. Second light reflecting layer 42 SiO2 / Ta2O5 (11.5 pairs) Second electrode 32 See Example 1 Second compound semiconductor layer 22 p-GaN Active layer 23 InGaN (multiple quantum well structure) First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Ta2O5 (14 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ0445nm Number of light emitting elements: 100 x 100

[0131] Table 10: See the layout in Figure 12 Second light reflecting layer 42 SiO2 / SiN (9 pairs) Second electrode 32 See Example 1 Second compound semiconductor layer 22 p-GaN Active layer 23 InGaN (multiple quantum well structure) First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Ta2O5 (14 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ0488nm Number of light emitting elements: 1000 x 1000

[0132] In the light-emitting element of Example 5, the base surface is uneven and differentiable, so that when a strong external force is applied to the light-emitting element for some reason, the problem of stress concentration on the rising part of the convex part can be reliably avoided, and there is no risk of damage to the first compound semiconductor layer, etc. In particular, in the light-emitting element array, bumps are used to connect and bond to an external circuit, etc., and a large load (for example, about 50 MPa) needs to be applied to the light-emitting element array during bonding. In the light-emitting element array of Example 5, even if such a large load is applied, there is no risk of damage to the light-emitting element array. In addition, because the base surface is uneven, the generation of stray light is further suppressed, and the generation of optical crosstalk between the light-emitting elements can be more reliably prevented.

[0133] When emitting elements are arranged in a light-emitting element array, the footprint diameter of the sacrificial layer described above cannot exceed the formation pitch of the light-emitting elements. Therefore, in order to narrow the formation pitch of the light-emitting element array, it is necessary to reduce the footprint diameter. Incidentally, the radius of curvature R1 of the center of the first portion 91 of the base surface 90 is positively correlated with the footprint diameter. In other words, when the footprint diameter becomes smaller with the narrow formation pitch, the radius of curvature R1 tends to become smaller as a result. For example, a radius of curvature R1 of about 30 μm for a footprint diameter of 24 μm has been reported. In addition, the radiation angle of light emitted from the light-emitting element is negatively correlated with the footprint diameter. In other words, when the footprint diameter becomes smaller with the narrow formation pitch, the radius of curvature R1 becomes smaller and the FFP (Far Field Pattern) tends to expand as a result. With a radius of curvature R1 of less than 30 μm, the radiation angle may be several degrees or more. Depending on the application field of the light-emitting element array, a narrow radiation angle of 2 to 3 degrees or less may be required for the light emitted from the light-emitting element.

[0134] In the fifth embodiment, since the first portion 91 and the second portion 92 are formed on the base surface 90, a large radius of curvature R1 can be achieved even when the light emitting elements are arranged at a narrow pitch. Therefore, it is possible to set the radiation angle of the light emitted from the light emitting element to a narrow radiation angle of 2 to 3 degrees or less, or to the narrowest possible radiation angle, and it is possible to provide a light emitting element having a narrow FFP, and to increase the light output and improve the efficiency of the light emitting element. Moreover, since the height (thickness) of the first portion 91 can be made low (thin), when the light emitting element array is connected and bonded to an external circuit or the like using bumps, cavities (voids) are unlikely to occur in the bumps, and the thermal conductivity can be improved. It goes without saying that the above description can also be applied to the light emitting elements of the first to fourth embodiments and the sixth to eleventh embodiments described later.

[0135] A method for manufacturing the light emitting device of Example 5 will be described below.

[0136] First, the same steps as [Step-100] to [Step-150] in Example 1 are performed. After that, a first sacrificial layer 81 is formed on a first portion 91 of a base surface 90 (specifically, a first surface 21a of a first compound semiconductor layer 21) on which a first light reflection layer 41 is to be formed, and then the surface of the first sacrificial layer is made convex. Specifically, a first resist material layer is formed on the first surface 21a of a first compound semiconductor layer 21, and the first resist material layer is patterned so as to leave the first resist material layer on the first portion 91, thereby obtaining the first sacrificial layer 81 shown in FIG. 35A. Then, the first sacrificial layer 81 is subjected to a heat treatment, thereby obtaining a structure shown in FIG. 35B. Next, an ashing treatment is performed on the surface of the first sacrificial layer 81' (a plasma irradiation treatment is performed) to alter the surface of the first sacrificial layer 81', and when a second sacrificial layer 82 is formed in the next step, damage, deformation, and the like are prevented from occurring in the first sacrificial layer 81'.

[0137] Next, a second sacrificial layer 82 is formed on the second portion 92 of the base surface 90 exposed between the first sacrificial layers 81' and on the first sacrificial layer 81' to make the surface of the second sacrificial layer 82 uneven (see FIG. 36A). Specifically, the second sacrificial layer 82 made of a second resist material layer having an appropriate thickness is formed on the entire surface. In the example of the arrangement shown in FIG. 11, the average film thickness of the second sacrificial layer 82 is 2 μm, and in the example of the arrangement shown in FIG. 12, the average film thickness of the second sacrificial layer 82 is 5 μm.

[0138] Alternatively, after forming a first sacrificial layer 81 on the first surface 21a of the first compound semiconductor layer 21, the surface of the first sacrificial layer 81 is made convex (see Figs. 35A and 35B), and then the first sacrificial layer 81' is etched back, and the first compound semiconductor layer 21 is further etched back from the first surface 21a toward the inside, thereby forming a convex portion 91' when the second surface 21b of the first compound semiconductor layer 21 is used as a reference. In this way, the structure shown in Fig. 37A can be obtained. Then, a second sacrificial layer 82 is formed on the entire surface (see Fig. 37B).

[0139] The material constituting the first sacrificial layer 81 and the second sacrificial layer 82 is not limited to a resist material, and may be an oxide material (e.g., SiO2, SiN, TiO2, etc.), a semiconductor material (e.g., Si, GaN, InP, GaAs, etc.), a metal material (e.g., Ni, Au, Pt, Sn, Ga, In, Al, etc.), or other material appropriate for the first compound semiconductor layer 21. In addition, by using a resist material having an appropriate viscosity as the resist material constituting the first sacrificial layer 81 and the second sacrificial layer 82, and by appropriately setting and selecting the thickness of the first sacrificial layer 81, the thickness of the second sacrificial layer 82, the diameter of the first sacrificial layer 81', etc., the value of the radius of curvature of the base surface 90 and the shape of the unevenness of the base surface 90 (e.g., the diameter D1 and the height H1) can be set to a desired value and shape.

[0140] Thereafter, the second sacrificial layer 82 and the first sacrificial layer 81' are etched back, and further etched back from the base surface 90 toward the inside (i.e., from the first surface 21a of the first compound semiconductor layer 21 toward the inside of the first compound semiconductor layer 21), thereby forming a convex portion 91A on the first portion 91 of the base surface 90 and at least a concave portion (in the fifth embodiment, a concave portion 92A) on the second portion 92 of the base surface 90, when the second surface 21b of the first compound semiconductor layer 21 is taken as a reference. In this way, the structure shown in FIG. 36B or FIG. 37C can be obtained. If it is necessary to further increase the radius of curvature R1 of the first portion 91 of the base surface 90, this process can be repeated. The etch back can be performed based on a dry etching method such as the RIE method, or based on a wet etching method using hydrochloric acid, nitric acid, hydrofluoric acid, phosphoric acid, a mixture thereof, or the like.

[0141] Next, the first light reflecting layer 41 is formed on the first portion 91 of the base surface 90. Specifically, after forming the first light reflecting layer 41 on the entire surface of the base surface 90 based on a film forming method such as a sputtering method or a vacuum deposition method (see FIG. 36C), the first light reflecting layer 41 is patterned to obtain the first light reflecting layer 41 on the first portion 91 of the base surface 90 (see FIG. 38A). Then, the first electrode 31 common to each light emitting element is formed on the second portion 92 of the base surface 90 (see FIG. 38B). In this manner, the light emitting element array or the light emitting element 10D of the fifth embodiment can be obtained. If the first electrode 31 is made to protrude from the first light reflecting layer 41, the first light reflecting layer 41 can be protected. Then, it is sufficient to electrically connect it to an external electrode or circuit (a circuit that drives the light emitting element). Specifically, the first compound semiconductor layer 21 may be connected to an external circuit or the like via the first electrode 31 and a first pad electrode (not shown), and the second compound semiconductor layer 22 may be connected to an external circuit or the like via the second electrode 32 and a second pad electrode. Next, the light-emitting device of Example 5 is completed by packaging or sealing. EXAMPLES

[0142] Example 6 is a modification of Example 5 and relates to a light-emitting element having a B-th configuration. A schematic partial end view of a light-emitting element 10E of Example 6 is shown in FIG. 13, and a schematic partial end view of a light-emitting element array including a plurality of light-emitting elements 10E of Example 6 is shown in FIG. 14. In addition, schematic plan views of the arrangement of the first and second parts of the base surface in the light-emitting element array of Example 6 are shown in FIG. 15 and FIG. 17, and schematic plan views of the arrangement of the first light reflecting layer and the first electrode in the light-emitting element array of Example 6 are shown in FIG. 16 and FIG. 18. Furthermore, schematic partial end views of the first compound semiconductor layer and the like for explaining the manufacturing method of the light-emitting element array of Example 6 are shown in FIG. 39A, FIG. 39B, FIG. 40A, FIG. 40B, FIG. 41A, and FIG. 41B.

[0143] In the light emitting device 10E of Example 6, when the second surface 21b of the first compound semiconductor layer 21 is used as a reference, the second portion 92 of the base surface 90 occupying the peripheral region 99 has a downwardly convex shape toward the center of the peripheral region 99 and an upwardly convex shape extending from the downwardly convex shape. c LL1 is a distance from the second surface 21b of the first compound semiconductor layer 21 to the center 92 of the second portion 92 of the base surface 90. c When the distance to is LL2, LL2>LL1 In addition, the central portion 91 of the first portion 91 of the base surface 90 c The radius of curvature of the first light reflecting layer 41 (i.e., the radius of curvature of the first light reflecting layer 41) is R1, and the radius of curvature of the second portion 92 of the base surface 90 is R2. c When the radius of curvature is R2, R1>R2 The value of LL2 / LL1 is not limited to the following: 1 <LL2 / LL1≦100 The value of R1 / R2 can be, but is not limited to, 1 <R1 / R2≦100 Specifically, for example, LL2 / LL1=1.05 R1 / R2=10 It is.

[0144] In the light emitting device 10E of the sixth embodiment, the central portion 91 of the first portion 91 of the base surface 90 c are located on the vertices (intersections) of a square grid (see FIG. 15 ), in this case the central portion 92 of the second portion 92 of the base surface 90. c 15) are located on the vertices (intersections) of the square grid. Alternatively, the central portion 91 of the first portion 91 of the base surface 90 c are located on the vertices (intersections) of a lattice of equilateral triangles (see FIG. 17 ), and in this case, the central portion 92 of the second portion 92 of the base surface 90 c 15 and 17, the second portion 92 of the base surface 90 occupying the peripheral region 99 has a downwardly convex shape toward the center of the peripheral region 99. b As shown in.

[0145] In the light-emitting element 10E of Example 6, the shape [from the peripheral parts to the center parts of the first portion 91 / second portion 92] corresponds to case (A) among cases (A) to (C) in the light-emitting element of the above-mentioned B configuration, specifically case (A).

[0146] In the light emitting element 10E of Example 6, a bump 35 is provided on a portion of the second compound semiconductor layer 22 on the second surface side facing the convex shaped portion of the second portion 92 of the base surface 90.

[0147] As shown in Fig. 13, the second electrode 32 is common to the light-emitting elements 10E constituting the light-emitting element array, or alternatively, as shown in Fig. 14, it is formed individually and is connected to an external circuit or the like via a second pad electrode 33 and a bump 35. The first electrode 31 is common to the light-emitting elements 10E constituting the light-emitting element array, and is connected to an external circuit or the like via a first pad electrode (not shown). The bump 35 is formed by bonding a convex portion 92 in a second portion 92 of the base surface 90 to the second pad electrode 33. c13 and 14, light may be emitted to the outside via the first light reflecting layer 41, or light may be emitted to the outside via the second light reflecting layer 42. Examples of the shape of the bump 35 include a cylindrical shape, an annular shape, and a hemispherical shape.

[0148] Also, the central portion 92 of the second portion 92 of the base surface 90 c The radius of curvature R2 is 1×10 -6 m or more, preferably 3×10 -6 m or more, preferably 5×10 -6 m or more. Specifically, Radius of curvature R2=3μm It is.

[0149] In the light-emitting element array of Example 6 shown in Figures 15 and 16, as well as Figures 17 and 18, the parameters of the light-emitting element 10E are as shown in Table 11 below. The specifications of the light-emitting element 10E of Example 6 shown in Figures 15 and 16, as well as Figures 17 and 18 are shown in Tables 12 and 13 below. Here, the height H1 of the first portion 91 is the distance from the second surface 21b of the first compound semiconductor layer 21 to the central portion 91 of the first portion 91 on the base surface 90. c LL1 is a distance from the second surface 21b of the first compound semiconductor layer 21 to the deepest recessed portion 92 of the second portion 92 of the base surface 90. b When the distance to the H1=LL1-LL2” and the center 92 of the second portion 92 c The height H2 of H2=LL2-LL2” It is expressed as:

[0150] See Figures 15 and 16. See Figures 17 and 18. Formation pitch 25μm 25μm Radius of curvature R1150μm 150μm Diameter D120μm 20μm Height H12μm 2μm Radius of curvature R22μm 2μm Height H22.5μm 2.5μm

[0151] See Figures 15 and 16 Second light reflecting layer 42 SiO2 / Ta2O5 (11.5 pairs) Second electrode 32 See Example 1 Second compound semiconductor layer 22 p-GaN Active layer 23 InGaN (multiple quantum well structure) First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Ta2O5 (14 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ0445nm Number of light emitting elements: 100 x 100

[0152] See Figures 17 and 18 Second light reflecting layer 42 SiO2 / Ta2O5 (11.5 pairs) Second electrode 32 See Example 1 Second compound semiconductor layer 22 p-GaN Active layer 23 InGaN (multiple quantum well structure) First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Ta2O5 (14 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ0445nm Number of light emitting elements: 100 x 100

[0153] 39A, 39B, 40A, 40B, 41A, and 41B are schematic partial end views of the first compound semiconductor layer and the like for explaining the manufacturing method of the light-emitting element array of Example 6. However, since the manufacturing method of the light-emitting element array of Example 6 can be substantially the same as the manufacturing method of the light-emitting element array of Example 5, detailed description will be omitted. Note that reference numeral 83 in FIG. 39A and reference numeral 83' in FIG. 39B and FIG. 40A indicate the central portion 92 of the second portion 92.c 1 shows a portion of the first sacrificial layer for forming the first sacrificial layer. Note that as the size (diameter) of the first sacrificial layer becomes smaller, the height of the first sacrificial layer after the heat treatment becomes higher.

[0154] In the light-emitting element array of Example 6 or Example 7 described later, when connecting and bonding to an external circuit or the like using the bumps 35, a large load (for example, about 50 MPa) needs to be applied to the light-emitting element array during bonding. In the light-emitting element array of Example 6, even if such a large load is applied, the bumps 35 and the convex portion 92 of the second portion 92 of the base surface 90 can be easily bonded to each other. c Since the light emitting element array is aligned in a vertical direction, it is possible to reliably prevent damage to the light emitting element array. EXAMPLES

[0155] Example 7 is a modification of Examples 5 to 6, and relates to a light-emitting element of Configuration C. Schematic partial end views of the light-emitting element array of Example 7 are shown in Fig. 19 and Fig. 20, and a schematic plan view of the arrangement of the first and second parts of the base surface in the light-emitting element array of Example 7 is shown in Fig. 21. In the example shown in Fig. 19, the second electrode 32 is formed individually for each light-emitting element, while in the example shown in Fig. 20, the second electrode 32 is formed in common for each light-emitting element.

[0156] In the light-emitting element 10F of Example 7, when the second surface 21b of the first compound semiconductor layer 21 is used as a reference, the second portion 92 of the base surface 90 occupying the peripheral region 99 has an annular convex shape 93 that surrounds the first portion 91 of the base surface 90, and a downwardly convex shape 94A that extends from the annular convex shape 93 toward the first portion 91 of the base surface 90. In the second portion 92 of the base surface 90 occupying the peripheral region 99, the region surrounded by the annular convex shape 93 is indicated by reference number 94B.

[0157] In the light emitting device 10F of Example 7, the first compound semiconductor layer 21 is formed on the second surface 21b of the first compound semiconductor layer 21. cis a distance from the second surface 21b of the first compound semiconductor layer 21 to the apex of the annular convex shape 93 of the second portion 92 of the base surface 90, LL2'>LL1 In addition, the central portion 91 of the first portion 91 of the base surface 90 c (i.e., the radius of curvature of the first light reflecting layer 41) is R1, and the radius of curvature of the apex of the annular convex shape 93 of the second portion 92 of the base surface 90 is R2′. R1>R2' The value of LL2' / LL1 is not limited to the following: 1 <LL2’ / LL1≦100 Specifically, for example, LL2' / LL1=1.1 In addition, the value of R1 / R2' is not limited to the following: 1 <R1 / R2’≦100 Specifically, for example, R1 / R2'=50 It is.

[0158] In the light-emitting element 10F of Example 7, the shape [from the peripheral parts to the center parts of the first portion 91 / second portion 92] corresponds to case (A) among cases (A) to (F) in the light-emitting element of the above-mentioned C configuration, specifically case (A).

[0159] In the light emitting device 10F of Example 7, a bump 35 is disposed on a portion of the second surface side of the second compound semiconductor layer 22 that faces the portion of the annular convex shape 93 in the second portion 92 of the base surface 90. The bump 35 is preferably in a ring shape that faces the annular convex shape 93. Examples of the shape of the bump 35 include a cylindrical shape, an annular shape, and a hemispherical shape. The bump 35 is disposed on the portion of the convex shape 92 in the second portion 92 of the base surface 90. c The second compound semiconductor layer 22 is formed in a portion on the second surface side thereof facing the first compound semiconductor layer 22.

[0160] As shown in FIG. 19, the second electrode 32 is formed individually in the light emitting element 10F constituting the light emitting element array, and is connected to an external circuit or the like via a bump 35. The first electrode 31 is common to the light emitting element 10F constituting the light emitting element array, and is connected to an external circuit or the like via a first pad electrode (not shown). Alternatively, as shown in FIG. 20, the second electrode 32 is common to the light emitting element 10F constituting the light emitting element array, and is connected to an external circuit or the like via a bump 35. The first electrode 31 is common to the light emitting element 10F constituting the light emitting element array, and is connected to an external circuit or the like via a first pad electrode (not shown). In the light emitting element 10F shown in FIG. 19 and FIG. 20, light may be emitted to the outside via the first light reflecting layer 41, or light may be emitted to the outside via the second light reflecting layer 42.

[0161] The radius of curvature R2' of the annular convex shape 93 of the second portion 92 of the base surface 90 is 1×10 -6 m or more, preferably 3×10 -6 m or more, preferably 5×10 -6 m or more. Specifically, Radius of curvature R2'=5μm It is.

[0162] In the light-emitting element array of Example 7 shown in Fig. 21, the parameters of the light-emitting element 10F are as shown in Table 14 below. The specifications of the light-emitting element 10F of Example 7 shown in Fig. 21 are shown in Table 15 below. Here, the height H1 of the first portion 91 is the distance from the second surface 21b of the first compound semiconductor layer 21 to the central portion 91 of the first portion 91 on the base surface 90. c LL1 is a distance from the second surface 21b of the first compound semiconductor layer 21 to the deepest recessed portion 92 of the second portion 92 of the base surface 90. b When the distance to the H1=LL1-LL2” and the height H2 of the annular convex shape 93 of the second portion 92 is represented by H2=LL2-LL2” In addition, the diameter D2 indicates the diameter of the annular convex shape 93.

[0163] See Figure 21 Formation pitch: 25μm Curvature radius R1150μm Diameter D115μm Height H12μm Curvature radius R23μm Diameter D219μm (inner diameter 18μm / outer diameter 20μm) Height H23μm

[0164] Table 15 See Figure 21 Second light reflective layer 42 SiO2 / Ta2O5 (7 pairs) Second electrode 32 See Example 1 Second compound semiconductor layer 22 p-GaN Active layer 23 InGaN (multiple quantum well structure) First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Ta2O5 (14 pairs) Resonator length L OR 20μm Oscillation wavelength (emission wavelength) λ0405nm Number of light emitting elements: 1000 x 1000

[0165] The manufacturing method of the light-emitting element array of the seventh embodiment can be substantially the same as the manufacturing method of the light-emitting element array of the fifth embodiment or the sixth embodiment, so a detailed description thereof will be omitted. EXAMPLES

[0166] Example 8 is a modification of Example 5. FIGS. 22A and 22B are schematic plan views showing the arrangement of the first and second parts of the base surface in the light-emitting element array of Example 8. In the example shown in FIG. 22A, the light-emitting element array has, for example, the light-emitting elements of Example 5 arranged in a row. The schematic partial end view along the arrow AA in FIG. 22A is similar to that shown in FIG. 9. In the example shown in FIG. 22B, the light-emitting element array has, for example, light-emitting elements whose planar shape is longer and thinner than the light-emitting elements of Example 5 arranged in a row. The schematic partial end view along the arrow AA in FIG. 22B is similar to that shown in FIG. 9. In the light-emitting element array of Example 8 shown in FIG. 22A, the parameters of the light-emitting elements are as shown in Table 16 below, and the specifications of the light-emitting elements are shown in Table 17 below. In addition, in the light-emitting element array of Example 8 shown in FIG. 22B, the parameters of the light-emitting elements are as shown in Table 18 below, and the specifications of the light-emitting elements are shown in Table 19 below. The shape of the base surface shown in FIG. 22B is a part of a cylindrical shape or a part of a semi-cylindrical shape.

[0167] See Figure 22A Formation pitch: 25μm Curvature radius R1100μm Diameter D120μm Height H12μm

[0168] Table 17 See Figure 22A Second light reflecting layer 42 SiO2 / Ta2O5 (11.5 pairs) Second electrode 32 See Example 1 Second compound semiconductor layer 22 p-GaN Active layer 23 InGaN (multiple quantum well structure) First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Ta2O5 (14 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ0445nm Number of light emitting elements: 1000 x 1

[0169] See Figure 22B Formation pitch: 25 μm (pitch along arrow B in FIG. 22B) Radius of curvature R1100 μm (radius of curvature in the direction of arrow B in Figure 22B) Size of the first part: length 400μm × width 20μm Height H12μm

[0170] Table 19 See Figure 22B Second light reflecting layer 42 SiO2 / Ta2O5 (11.5 pairs) Second electrode 32 See Example 1 Second compound semiconductor layer 22 p-GaN Active layer 23 InGaN (multiple quantum well structure) First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Ta2O5 (14 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ0445nm Number of light emitting elements: 512 x 1 EXAMPLES

[0171] Example 9 is a modification of Example 3, Example 4, and Examples 5 to 8. The configuration and structure of the light-emitting element of Example 9 can be substantially the same as the configuration and structure of the light-emitting element of Examples 3, 4, and Examples 5 to 8, and therefore detailed description thereof will be omitted.

[0172] In Example 9, first, the unevenness 96 for forming the base surface 90 is formed on the second surface 11b of the light-emitting element manufacturing substrate 11 (see FIG. 42A). Then, the first light reflecting layer 41 made of a multilayer film is formed on the second surface 11b of the light-emitting element manufacturing substrate 11 (see FIG. 42B), and then a planarizing film 97 is formed on the first light reflecting layer 41 and the second surface 11b, and a planarizing process is performed on the planarizing film 97 (see FIG. 42C).

[0173] Next, a stacked structure 20 is formed based on lateral growth using a method of epitaxial growth in the lateral direction, such as an ELO method, on the planarization film 97 of the substrate 11 for manufacturing light-emitting elements, including the first light reflecting layer 41. Thereafter, the substrate 11 for manufacturing light-emitting elements is removed, and the first electrode 31 is formed on the exposed planarization film 97. Alternatively, the first electrode 31 is formed on the first surface 11a of the substrate 11 for manufacturing light-emitting elements, without removing the substrate 11 for manufacturing light-emitting elements. EXAMPLES

[0174] Example 10 is a modification of Examples 1 to 9. In the light-emitting element of Example 10, partition walls 24 and 25 extending in the stacking direction of the stacked structure 20 are formed so as to surround the first light reflecting layer 41. By forming the partition walls 24 and 25, the occurrence of optical crosstalk can be prevented.

[0175] A partition extending in the stacking direction of the laminated structure 20 is formed so as to surround the first light reflecting layer 41. The orthogonal projection image of the first light reflecting layer 41 may be included in an orthogonal projection image (hereinafter, sometimes referred to as an "orthogonal projection image of the partition side") of a side surface of the partition facing the first light reflecting layer 41 (hereinafter, sometimes referred to as a "partition side surface"), or the orthogonal projection image of the partition side surface may be included in an orthogonal projection image of a portion of the first light reflecting layer 41 that does not contribute to light reflection (a non-effective region of the first light reflecting layer 41). Alternatively, the base surface 90 on which the first light reflecting layer 41 is formed may be included in an orthogonal projection image of the partition side surface. The partition side surface may be a continuous surface or a discontinuous surface with a portion cut out. The "orthogonal projection image" means an orthogonal projection image obtained when orthogonally projected onto the laminated structure 20.

[0176] The partition 24 may extend from the first surface side of the first compound semiconductor layer 21 to the middle of the thickness direction of the first compound semiconductor layer 21 in the first compound semiconductor layer 21. That is, the upper end of the partition 24 may be located at the middle of the thickness direction of the first compound semiconductor layer 21. The lower end of the partition 24 may be exposed to the first surface of the light-emitting element, or may not be exposed to the first surface of the light-emitting element. Here, the "first surface of the light-emitting element" refers to the exposed surface of the light-emitting element on the side where the first light reflecting layer 41 is provided, and the "second surface of the light-emitting element" refers to the exposed surface of the light-emitting element on the side where the second light reflecting layer is provided. In the light-emitting element array of the present disclosure, the relationship between L0, L1, and L3 is as follows: The following formula (1) is satisfied, preferably formula (1') is satisfied, or The following formula (2) is satisfied, preferably the following formula (2'): The following formula (1) and formula (2) are satisfied, or It is desirable to satisfy the following formula (1') and formula (2'). 0.01×L0≦L0-L1(1) 0.05×L0≦L0-L1(1') 0.01×L3≦L1(2) 0.05×L3≦L1(2') Where: L0: the distance from the end of the surface of the first light reflecting layer 41 facing the first surface of the first compound semiconductor layer 21 to the active layer 23 L1: distance from the active layer 23 to an end of the partition wall 24 that extends partway through the first compound semiconductor layer 21 in the thickness direction of the first compound semiconductor layer 21 (the upper end of the partition wall 24 that faces the active layer 23) L3: the distance from the axis of the first light reflecting layer 41 constituting the light emitting element to the orthogonal projection image of the partition wall 24 onto the laminated structure 20 (more specifically, the orthogonal projection image of the upper end portion of the partition wall 24) Although the upper limit of (L0-L1) is less than L0, when no short circuit occurs between the active layer 23 and the first electrode due to the partition wall 24, the upper limit of (L0-L1) may be equal to or greater than L0.

[0177] Alternatively, the partition 25 may extend from the second surface side of the second compound semiconductor layer 22 into the second compound semiconductor layer 22 and into the active layer 23, and further extend into the first compound semiconductor layer 21 to the middle of the first compound semiconductor layer 21 in the thickness direction. That is, the lower end of the partition 25 may be located halfway through the first compound semiconductor layer 21 in the thickness direction. The upper end of the partition 25 may be exposed to the second surface of the light-emitting element in some cases, or may not be exposed to the second surface of the light-emitting element in other cases. In such a case, the relationship between L0, L2, and L3' is as follows: The following formula (3) is satisfied, preferably the following formula (3'): The following formula (4) is satisfied, preferably formula (4') is satisfied, or The following formulas (3) and (4) are satisfied, or It is desirable to satisfy the following formula (3') and formula (4'). 0.01×L0≦L2(3) 0.05×L0≦L2(3') 0.01×L3'≦L2(4) 0.05×L3'≦L2(4') Where: L0: the distance from the end of the surface of the first light reflecting layer 41 facing the first surface of the first compound semiconductor layer 21 to the active layer 23 L2: distance from the active layer 23 to an end of the partition wall 25 extending partway through the first compound semiconductor layer 21 in the thickness direction of the first compound semiconductor layer 21 (the lower end of the partition wall 25, the end facing the first electrode) L3': the distance from the axis of the first light reflecting layer 41 constituting the light emitting element to the orthogonal projection image of the partition wall 25 onto the laminated structure 20 (more specifically, the orthogonal projection image of the lower end of the partition wall 25) Although the upper limit of L2 is less than L0, in the case where a short circuit does not occur between the active layer 23 and the first electrode due to the partition wall 25, the upper limit of L2 may be L0.

[0178] The partitions 24 and 25 may be made of a material that does not transmit the light generated in the active layer 23, thereby preventing the generation of stray light and optical crosstalk. Specifically, such materials include materials capable of blocking light, such as titanium (Ti), chromium (Cr), tungsten (W), tantalum (Ta), aluminum (Al), and MoSi2, and may be formed by, for example, an electron beam deposition method, a hot filament deposition method, a deposition method including a vacuum deposition method, a sputtering method, a CVD method, an ion plating method, or the like. Alternatively, a black resin film having an optical density of 1 or more containing a black colorant (specifically, for example, a black polyimide resin, an epoxy resin, or a silicone resin) may be used.

[0179] Alternatively, the partitions 24 and 25 may be made of a material that reflects the light generated in the active layer 23, which can prevent the generation of stray light and optical crosstalk, and can efficiently return the stray light to the light-emitting element itself, thereby contributing to improving the light-emitting efficiency of the light-emitting element. Specifically, the partitions 24 and 25 are made of thin-film filters that utilize the interference of thin films. The thin-film filters have a different stacking direction (alternate arrangement direction) from, for example, the light-reflecting layers 41 and 42, but have the same configuration and structure. Specifically, a recess is formed in a part of the laminated structure 20, and the inside of this recess is filled sequentially with the same material as the light-reflecting layers 41 and 42 based on, for example, a sputtering method, so that when the partitions 24 and 25 are cut in a virtual plane (XZ plane) perpendicular to the stacking direction of the laminated structure 20, a thin-film filter in which dielectric layers are alternately arranged can be obtained. Alternatively, examples of such materials include metal materials, alloy materials, and metal oxide materials. More specifically, examples of such materials include copper (Cu) and its alloys, gold (Au) and its alloys, tin (Sn) and its alloys, silver (Ag) and its silver alloys (e.g., Ag-Pd-Cu, Ag-Sm-Cu), platinum (Pt) and its alloys, palladium (Pd) and its alloys, titanium (Ti) and its alloys, aluminum (Al) and its aluminum alloys (e.g., Al-Nd and Al-Cu), an Al / Ti laminated structure, an Al-Cu / Ti laminated structure, chromium (Cr) and its alloys, and ITO. For example, the material can be formed by deposition methods including electron beam deposition, hot filament deposition, and vacuum deposition, sputtering, CVD, and ion plating; plating methods (electroplating and electroless plating); lift-off methods; laser ablation methods; sol-gel methods; plating methods, and the like.

[0180] Alternatively, when the thermal conductivity of the material constituting the first compound semiconductor layer 21 is TC1 and the thermal conductivity of the material constituting the partition walls 24 and 25 is TC0, 1×10 -1 ≦TC1 / TC0≦1×10 2 The partition walls 24 and 25 can be formed in a form that satisfies the above. Specific examples of the material for forming the partition walls 24 and 25 include metals such as silver (Ag), copper (Cu), gold (Au), tin (Sn), aluminum (Al), ruthenium (Ru), rhodium (Rh), platinum (Pt), or alloys or mixtures of these metals, ITO, etc., and can be formed by, for example, an electron beam deposition method, a hot filament deposition method, a deposition method including a vacuum deposition method, a sputtering method, a CVD method, an ion plating method, a plating method (an electroplating method or an electroless plating method), a lift-off method, a laser ablation method, a sol-gel method, a plating method, etc. In this way, by forming the partition walls 24 and 25 from a material having a high thermal conductivity, the heat generated in the laminated structure 20 can be exhausted (dissipated) to the outside through the partition walls 24 and 25. In this case, a partition extension portion may be formed on the outer surface (first surface or second surface) of the light-emitting element so that heat generated in the laminated structure 20 can be exhausted (dissipated) to the outside via the partitions 24, 25 and the partition extension portion, or the partitions 24, 25 may be connected to the first electrode 31 or the second electrode 32 or the pad electrode so that heat generated in the laminated structure 20 can be exhausted (dissipated) to the outside via the partitions 24, 25 and the first electrode 31 or the second electrode 32 or the pad electrode.

[0181] Alternatively, when the linear expansion coefficient of the material constituting the first compound semiconductor layer 21 is CTE1 and the linear expansion coefficient of the material constituting the partition walls 24 and 25 is CTE0, |CTE0-CTE1|≦1×10 -4 / K The partition walls 24, 25 can be formed to satisfy the above. Specific examples of materials for the partition walls 24, 25 include polyimide resin, silicone resin, epoxy resin, carbon material, SOG, polycrystalline GaN, and single crystal GaN. By specifying the linear expansion coefficient in this way, the thermal expansion coefficient of the entire light-emitting element can be optimized, and the thermal expansion of the light-emitting element can be controlled (suppressed). Specifically, for example, the net thermal expansion coefficient of the laminated structure 20 can be increased, and by matching it with the thermal expansion coefficient of the substrate material on which the light-emitting element is mounted, it is possible to prevent damage to the light-emitting element and suppress a decrease in the reliability of the light-emitting element due to the generation of stress. The partition walls 24, 25 made of polyimide resin can be formed, for example, based on a spin-coating method and a curing method.

[0182] Alternatively, if the partitions 24 and 25 are made of an insulating material, the occurrence of electrical crosstalk can be suppressed, that is, unnecessary current can be prevented from flowing between adjacent light emitting elements.

[0183] Alternatively, the partition 25 may be made of a solder material, and a part of the partition 25 may be exposed to the outer surface of the light-emitting element. A kind of bump may be formed by the part of the partition 25 exposed to the outer surface of the light-emitting element. Specific examples of materials that may be used to form such partition 25 include Au-Sn eutectic solder, so-called low-melting point metal (alloy) materials, solder materials, and brazing materials, and examples of such materials include In (indium: melting point 157°C); indium-gold based low-melting point alloys; Sn 80 Ag 20 (Melting point 220~370℃), Sn 95 Cu5 (melting point 227-370°C) and other tin (Sn)-based high-temperature solders; Pb 97.5 Ag 2.5 (Melting point 304°C), Pb 94.5 Ag 5.5 (Melting point 304~365℃), Pb 97.5 Ag 1.5 Sn 1.0 (melting point 309°C) etc. Lead (Pb) based high temperature solder; Zn 95 Zinc (Zn) based high temperature solder such as Al5 (melting point 380°C); Sn5Pb95 (Melting point 300~314℃), Sn2Pb 98 (melting point 316~322℃) and other standard tin-lead solders; Au 88 Ga 12 (melting point 381°C) and other brazing materials (the above subscripts all indicate atomic %).

[0184] Furthermore, the side surface of the partition 25 can be narrowed along the direction from the first surface side of the first compound semiconductor layer 21 toward the second surface side of the second compound semiconductor layer 22. That is, the shape of the side surface of the partition 25 when the light emitting element is cut in a virtual plane (XZ plane) including the stacking direction of the stacked structure 20 can be a trapezoid (an isosceles trapezoid with the second compound semiconductor layer side being the short side and the first compound semiconductor layer side being the long side). This makes it possible to more efficiently return stray light to the light emitting element itself.

[0185] Examples of the shape of the side of the partitions 24 and 25 when the light emitting element is cut in a virtual plane (XZ plane) including the stacking direction of the laminated structure 20 include a line segment, an arc, a part of a parabola, and a part of an arbitrary curve. Examples of the shape of the side of the partitions 24 and 25 when the light emitting element is cut in a virtual plane (XY plane) perpendicular to the stacking direction of the laminated structure 20 include a circle, an ellipse, an oval, a rectangle including a square and a rectangle, and a regular polygon (including a rounded regular polygon). Specific examples of the planar shapes of the first light reflecting layer 41 and the second light reflecting layer include a circle, an ellipse, an oval, a rectangle, and a regular polygon (equilateral triangle, square, regular hexagon, etc.). It is desirable that the planar shapes of the first light reflecting layer 41 and the second light reflecting layer and the shape of the side of the partitions 24 and 25 when the light emitting element is cut in a virtual plane (XY plane) perpendicular to the stacking direction of the laminated structure 20 are similar or approximate.

[0186] When the light-emitting elements are arranged in an array, the partitions 24, 25 are provided so as to surround the first light reflecting layers 41 constituting each light-emitting element, but the region outside the side surface of the partition may be occupied by the partitions 24, 25 (i.e., the space between the light-emitting elements may be occupied by the material constituting the partitions 24, 25), or may be occupied by a material (e.g., the laminated structure 20) other than the material constituting the partitions 24, 25. In the latter case, the partitions 24, 25 are formed, for example, in the shape of a continuous groove or a discontinuous groove.

[0187] The light-emitting device 10G of Example 10 will be specifically described below.

[0188] 23 and 25 show schematic partial cross-sectional views of the light-emitting element array in Example 10, and Fig. 24 and 26 show schematic partial cross-sectional views of the light-emitting element 10G. Here, Fig. 23 and Fig. 24 show an example in which the partition 24 is made of a material having no conductivity, and Fig. 3 and Fig. 4 show an example in which the partition 24 is made of a material having conductivity or an example in which the partition 24 is made of a material having no conductivity. The partition 24 is formed to extend in the stacking direction of the stacked structure 20 so as to surround the first light reflecting layer 41.

[0189] As shown in the figure, the orthogonal projection image of the first light reflecting layer 41 may be included in the orthogonal projection image of the side surface 24' of the partition 24 facing the first light reflecting layer 41, or, although not shown, the orthogonal projection image of the partition side surface 24' may be included in the orthogonal projection image of a portion of the first light reflecting layer 41 that does not contribute to light reflection (a non-effective region of the first light reflecting layer 41). The side surface 24' of the partition 24 may be a continuous surface or a discontinuous surface with a portion cut out. The same can be applied to the partition 25 of Example 11 described later.

[0190] In the light-emitting element 10G of Example 10, the partition 24 extends from the first surface side of the first compound semiconductor layer 21 through the first compound semiconductor layer 21 to the middle of the thickness direction of the first compound semiconductor layer 21. That is, the upper end portion (the end portion facing the active layer 23) 24b of the partition 24 is located halfway through the thickness direction of the first compound semiconductor layer 21. In the light-emitting element array of Example 1, the relationship between L0, L1 and L3 satisfies the relationship described above. Specifically, it is as shown in Table 23 described later.

[0191] The partition 24 is made of a material that does not transmit the light generated in the active layer 23. Alternatively, when the thermal conductivity of the material constituting the first compound semiconductor layer 21 is TC1 and the thermal conductivity of the material constituting the partition 24 is TC0, 1×10 -1 ≦TC1 / TC0≦1×10 2 Specifically, the material constituting the first compound semiconductor layer 21 is made of GaN, and the partition wall 24 is made of copper (Cu). TC0: 50 W / (m K) to 100 W / (m K) TC1: 400 W / (m K) For example, when the partition wall 24 made of a copper layer is formed by a plating method, a base layer made of an Au layer or the like having a thickness of about 0.1 μm is formed in advance as a seed layer by a sputtering method or the like, and then a copper layer is formed thereon by a plating method. By forming the partition wall 24 from a material having high thermal conductivity in this manner, heat generated in the laminated structure 20 can be effectively exhausted (dissipated) to the outside through the partition wall 24.

[0192] Alternatively, the partition 24 is made of a material that reflects the light generated in the active layer 23, such as silver (Ag).

[0193] Alternatively, when the linear expansion coefficient of the material (GaN) constituting the first compound semiconductor layer 21 is CTE1 and the linear expansion coefficient of the material (polyimide resin) constituting the partition wall 24 is CTE0, |CTE0-CTE1|≦1×10 -4 / K Specifically, CTE0:5.5×10 -6 / K CTE1:25×10 -6 / K By combining these materials, the net thermal expansion coefficient of the light emitting element 10G can be increased and matched with the thermal expansion coefficient of the substrate material on which the light emitting element 10G is mounted, thereby preventing damage to the light emitting element 10G and a decrease in reliability due to stress generation in the light emitting element 10G.

[0194] When the light emitting element 10G is cut in a virtual plane (for example, the XZ plane in the illustrated example) including the stacking direction of the stacked structure 20, the shape of the side surface 24' of the partition 24 is a line segment. When the light emitting element 10G is cut in a virtual plane (the XY plane) perpendicular to the stacking direction of the stacked structure 20, the shape of the side surface 24' of the partition 24 is a circle. Furthermore, the partition 24 is provided so as to surround the first light reflecting layer 41 constituting each light emitting element 10G, and the region outside the side surface 24' of the partition 24 is occupied by the partition 24. That is, the space between the light emitting elements 10G is occupied by the material constituting the partition 24.

[0195] As shown in FIGS. 23 and 24, when the partition wall 24 is made of a material that has no electrical conductivity, a first electrode 31 is provided on the first surface 21a of the first compound semiconductor layer 21.

[0196] As shown in Figs. 25 and 26, when the partition 24 is made of a material having electrical conductivity, or when the partition 24 is made of a material having no electrical conductivity, the first electrode 31 may be provided on the exposed surface (lower end surface 24a) of the partition 24. Specifically, the lower end (end facing the first electrode 31) 24a of the partition 24 is in contact with the first electrode 31 formed on the first surface 10a (the first surface 21a of the first compound semiconductor layer 21) of the light-emitting element 10G. The second surface 10b of the light-emitting element 10G is the exposed surface of the light-emitting element. When the partition 24 is made of a material having electrical conductivity, the partition 24 may also serve as the first electrode 31. By making the partition 24 from a material having high thermal conductivity in this way, heat generated in the laminated structure 20 can be exhausted (dissipated) to the outside through the partition 24. Specifically, heat generated in the laminated structure 20 can be effectively discharged (dissipated) to the outside via the partition wall 24 and the first electrode 31 or the first pad electrode.

[0197] However, the present invention is not limited to this, and the space between the light emitting elements 10G may be occupied by a material (e.g., the laminated structure 20) other than the material constituting the partition 24. That is, the partition 24 may be formed, for example, in the shape of a continuous groove, or may be formed in the shape of a discontinuous groove.

[0198] The first compound semiconductor layer 21 has a first conductivity type (specifically, n-type), and the second compound semiconductor layer 22 has a second conductivity type (specifically, p-type) different from the first conductivity type. In the light emitting device 10G of Example 1, the first surface 21a of the first compound semiconductor layer 21 constitutes a base surface 90. The first light reflecting layer 41 is formed on the base surface 90. The base surface 90 has a convex shape extending in a direction away from the active layer 23.

[0199] 23, 24, 25, and 26, the second electrode 32 is common to the light-emitting elements 10G constituting the light-emitting element array, and the second electrode 32 is connected to an external circuit or the like via a first pad electrode (not shown). The first electrode 31 is also common to the light-emitting elements 10G constituting the light-emitting element array, and is connected to an external circuit or the like via a first pad electrode (not shown). Then, light may be emitted to the outside via the first light reflecting layer 41, or light may be emitted to the outside via the second light reflecting layer 42.

[0200] In the light-emitting element array of Example 10, the parameters of the light-emitting element 10G are as shown in Table 20 below. The diameter of the first light reflecting layer 41 is indicated by D1, and the height of the base surface 90 is indicated by H1 (see FIG. 23). The specifications of the light-emitting element 10G of Example 10 having the same arrangement as shown in FIG. 11 and FIG. 12 are shown in Tables 21 and 22 below. Furthermore, the values ​​of P0, L0, L1, and L3 are shown in Table 23, and the values ​​of P0, L0, L2, and L3' in Example 11 described later are shown in Table 24.

[0201] See Figure 11 See Figure 12 Formation pitch 25μm 20μm Radius of curvature R1100μm 200μm Diameter D120μm 15μm Height H12μm 2μm

[0202] See Figure 11 Second light reflecting layer 42 SiO2 / Ta2O5 (11.5 pairs) Second electrode 32 See Example 1 Second compound semiconductor layer 22 p-GaN Active layer 23 InGaN (multiple quantum well structure) First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Ta2O5 (14 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ0445nm Number of light emitting elements: 100 x 100

[0203] Table 22 See Figure 12 Second light reflecting layer 42 SiO2 / SiN (9 pairs) Second electrode 32 See Example 1 Second compound semiconductor layer 22 p-GaN Active layer 23 InGaN (multiple quantum well structure) First compound semiconductor layer 21 n-GaN First light reflecting layer 41 SiO2 / Ta2O5 (14 pairs) Resonator length L OR 25μm Oscillation wavelength (emission wavelength) λ0488nm Number of light emitting elements: 1000 x 1000

[0204] Table 23 Example 10 P0: 40μm L0: 30μm L1: 28μm L3: 18μm

[0205] Table 24 Example 11 P0: 20μm L0: 17μm L2: 12μm L3': 9μm

[0206] In the light-emitting element or light-emitting element array of Example 10, the partition wall 24 extending in the stacking direction of the stacked structure 20 is formed so as to surround the first light reflecting layer 41, so that it is possible to prevent the occurrence of optical crosstalk and / or the occurrence of thermal saturation. As a result, it is possible to provide a light-emitting element and a light-emitting element array having high light-emitting efficiency and high reliability. EXAMPLES

[0207] Example 11 is a modification of Example 10. A schematic partial cross-sectional view of a light-emitting element array of Example 11 is shown in Fig. 27, and a schematic partial cross-sectional view of a light-emitting element is shown in Fig. 28.

[0208] In the light-emitting element 10H of Example 11, the partition wall 25A extends from the second surface side of the second compound semiconductor layer 22 into the second compound semiconductor layer 22 and into the active layer 23, and further extends into the first compound semiconductor layer 21 to the middle of the thickness direction of the first compound semiconductor layer 21. That is, the lower end 25a of the partition wall 25A is located in the middle of the thickness direction of the first compound semiconductor layer 21. In the light-emitting element array of Example 11, the relationship between L0, L2, and L3' satisfies the above-mentioned relationship, as shown in Table 24 above. The upper end 25b of the partition wall 25B is exposed to the second surface 10b of the light-emitting element 10H.

[0209] 29 is a schematic partial cross-sectional view of a first modified example of the light-emitting element 10H of Example 11, the upper end 25b of the partition 25B does not have to be exposed to the second surface 10b of the light-emitting element 10H. Specifically, the upper end 25b of the partition 25B is covered with the insulating layer (current confinement layer) 34 and the second electrode 32.

[0210] 30 is a schematic partial cross-sectional view of Modification 2 of the light-emitting element 10H of Example 11, in which a side surface 25' of the partition wall 25C narrows in a direction from the first surface side of the first compound semiconductor layer 21 toward the second surface side of the second compound semiconductor layer 22. That is, when the light-emitting element 10H is cut along a virtual plane (for example, the XZ plane in the illustrated example) including the stacking direction of the stacked structure 20, the shape of the side surface of the partition wall 25C is a trapezoid, specifically, an isosceles trapezoid with the short side on the second compound semiconductor layer side and the long side on the first compound semiconductor layer side.

[0211] These partitions 25A, 25B, and 25C can be made of the same material as the partition 24 described in the tenth embodiment.

[0212] 31 is a schematic partial cross-sectional view of Modification 3 of the light-emitting element 10H of Example 11, in which the partition 25D is made of a solder material, specifically, for example, Au-Sn eutectic solder, and a portion 25D' of the partition 25D is formed on the outer surface (second surface 10b) of the light-emitting element 10H. Specifically, the portion 25D' of the partition 25D exposed from the second surface 10b of the light-emitting element 10 forms a kind of bump, and the light-emitting element 10 can be connected to an external circuit or the like via the portion 25D' of the partition 25D.

[0213] Although the present disclosure has been described above based on preferred embodiments, the present disclosure is not limited to these embodiments. The configuration and structure of the light-emitting element described in the embodiments are illustrative and can be appropriately changed, and the manufacturing method of the light-emitting element can also be appropriately changed. In some cases, by appropriately selecting the bonding layer and the support substrate, a surface-emitting laser element that emits light from the second surface of the second compound semiconductor layer through the second light reflecting layer can be obtained. In some cases, a through hole leading to the first compound semiconductor layer can be formed in the region of the second compound semiconductor layer and the active layer that does not affect the light emission, and a first electrode insulated from the second compound semiconductor layer and the active layer can be formed in the through hole. The first light reflecting layer may extend to the second portion of the base surface. That is, the first light reflecting layer on the base surface may be composed of a so-called solid film. In this case, a through hole is formed in the first light reflecting layer that extends to the second portion of the base surface, and a first electrode connected to the first compound semiconductor layer is formed in the through hole. In addition, the base surface 90 can be formed by providing a sacrificial layer based on the nanoimprint method.

[0214] A wavelength conversion material layer (color conversion material layer) may be provided in the region from which the light of the light emitting element is emitted. In this case, white light may be emitted through the wavelength conversion material layer (color conversion material layer). Specifically, when the light emitted from the active layer is emitted to the outside through the first light reflecting layer, the wavelength conversion material layer (color conversion material layer) may be formed on the light emitting side of the first light reflecting layer, and when the light emitted from the active layer is emitted to the outside through the second light reflecting layer, the wavelength conversion material layer (color conversion material layer) may be formed on the light emitting side of the second light reflecting layer.

[0215] When blue light is emitted from the light emitting layer, the following configuration can be adopted to make it possible to emit white light via the wavelength converting material layer. [A] By using a wavelength converting material layer that converts the blue light emitted from the light emitting layer into yellow light, white light that is a mixture of blue and yellow light is obtained as the light emitted from the wavelength converting material layer. [B] By using a wavelength converting material layer that converts the blue light emitted from the light emitting layer into orange light, white light that is a mixture of blue and orange is obtained as the light emitted from the wavelength converting material layer. [C] By using a wavelength converting material layer that converts the blue light emitted from the light emitting layer to green light and a wavelength converting material layer that converts it to red light, white light that is a mixture of blue, green, and red is obtained as the light emitted from the wavelength converting material layer.

[0216] Alternatively, when ultraviolet light is emitted from the light emitting layer, the following configuration can be adopted to make it possible to emit white light via the wavelength converting material layer. [D] By using a wavelength converting material layer that converts the ultraviolet light emitted from the light emitting layer into blue light and a wavelength converting material layer that converts it into yellow light, white light that is a mixture of blue and yellow is obtained as the light emitted from the wavelength converting material layer. [E] By using a wavelength converting material layer that converts the ultraviolet light emitted from the light emitting layer into blue light and a wavelength converting material layer that converts it into orange light, white light that is a mixture of blue and orange is obtained as the light emitted from the wavelength converting material layer. [F] By using a wavelength converting material layer that converts the ultraviolet light emitted from the light emitting layer into blue light, a wavelength converting material layer that converts it into green light, and a wavelength converting material layer that converts it into red light, white light that is a mixture of blue, green, and red is obtained as the light emitted from the wavelength converting material layer.

[0217] Here, examples of wavelength conversion materials that are excited by blue light and emit red light include red-emitting phosphor particles, more specifically, (ME:Eu)S [wherein "ME" means at least one type of atom selected from the group consisting of Ca, Sr, and Ba, and the same applies below], (M:Sm) x (Si,Al) 12 (O,N) 16 [wherein "M" means at least one atom selected from the group consisting of Li, Mg, and Ca, and the same applies below], ME2Si5N8:Eu, (Ca:Eu)SiN2, and (Ca:Eu)AlSiN3 can be given. In addition, examples of wavelength conversion materials that are excited by blue light and emit green light include green-emitting phosphor particles, more specifically, (ME:Eu)Ga2S4, (M:RE) x (Si,Al) 12 (O,N) 16 [wherein "RE" means Tb and Yb], (M:Tb) x (Si,Al) 12 (O,N) 16 , (M:Yb) x (Si,Al) 12 (O,N) 16 , Si 6-Z Al Z O Z N 8-Z:Eu can be mentioned. Furthermore, as a wavelength conversion material that is excited by blue light and emits yellow light, specifically, yellow light emitting phosphor particles, more specifically, YAG (yttrium aluminum garnet) phosphor particles can be mentioned. The wavelength conversion material may be one type, or two or more types may be mixed and used. Furthermore, by using a mixture of two or more types of wavelength conversion materials, it is possible to configure the wavelength conversion material mixture to emit light of a color other than yellow, green, and red. Specifically, for example, it may be configured to emit cyan light, in which case green light emitting phosphor particles (for example, LaPO4:Ce,Tb,BaMgAl 10 O 17 :Eu,Mn,Zn2SiO4:Mn,MgAl 11 O 19 :Ce,Tb,Y2SiO5:Ce,Tb,MgAl 11 O 19 :CE,Tb,Mn) and blue-emitting phosphor particles (e.g., BaMgAl 10 O 17 :Eu, BaMg2Al 16 O 27 :Eu, Sr2P2O7:Eu, Sr5(PO4)3Cl:Eu, (Sr,Ca,Ba,Mg)5(PO4)3Cl:Eu, CaWO4, CaWO4:Pb) can be used.

[0218] In addition, examples of wavelength conversion materials that are excited by ultraviolet light and emit red light include red-emitting phosphor particles, more specifically, Y2O3:Eu, YVO4:Eu, Y(P,V)O4:Eu, 3.5MgO·0.5MgF2·Ge2:Mn, CaSiO3:Pb,Mn, and Mg6AsO 11 :Mn, (Sr,Mg)3(PO4)3:Sn, La2O2S:Eu, and Y2O2S:Eu. In addition, examples of wavelength conversion materials that are excited by ultraviolet light and emit green light include green light-emitting phosphor particles, more specifically, LaPO4:Ce,Tb, BaMgAl 10 O 17 :Eu,Mn,Zn2SiO4:Mn,MgAl 11 O 19:Ce,Tb,Y2SiO5:Ce,Tb,MgAl 11 O 19 : Ce, Tb, Mn, Si 6-Z Al Z O Z N 8-Z Furthermore, examples of wavelength conversion materials that are excited by ultraviolet light and emit blue light include blue light-emitting phosphor particles, more specifically BaMgAl 10 O 17 :Eu, BaMg2Al 16 O 27 :Eu, Sr2P2O7:Eu, Sr5(PO4)3Cl:Eu, (Sr,Ca,Ba,Mg)5(PO4)3Cl:Eu, CaWO4, CaWO4:Pb can be mentioned. Furthermore, as a wavelength conversion material that is excited by ultraviolet light and emits yellow light, specifically, yellow light emitting phosphor particles, more specifically, YAG phosphor particles can be mentioned. The wavelength conversion material may be one type, or two or more types may be mixed and used. Furthermore, by using a mixture of two or more types of wavelength conversion materials, it is possible to configure the wavelength conversion material mixture to emit light of a color other than yellow, green, and red. Specifically, it may be configured to emit cyan light, and in this case, a mixture of the above-mentioned green light emitting phosphor particles and blue light emitting phosphor particles may be used.

[0219] However, the wavelength conversion material (color conversion material) is not limited to phosphor particles, and examples of such materials include light-emitting particles that apply quantum well structures such as a two-dimensional quantum well structure, a one-dimensional quantum well structure (quantum wire), and a zero-dimensional quantum well structure (quantum dot) that localize the wave function of carriers and use the quantum effect in indirect transition silicon-based materials to efficiently convert carriers into light, as in the case of direct transition materials, and it is known that rare earth atoms added to semiconductor materials emit light sharply due to intrashell transitions, and examples of such light-emitting particles that apply such techniques can also be mentioned.

[0220] As described above, quantum dots can be cited as wavelength conversion materials (color conversion materials). As the size (diameter) of a quantum dot becomes smaller, the band gap energy becomes larger, and the wavelength of light emitted from the quantum dot becomes shorter. That is, the smaller the size of a quantum dot, the shorter the wavelength of light (light on the blue light side) that it emits, and the larger the size, the longer the wavelength of light (light on the red light side) that it emits. Therefore, by using the same material to compose the quantum dot and adjusting the size of the quantum dot, it is possible to obtain quantum dots that emit light with a desired wavelength (color conversion to a desired color). Specifically, it is preferable that the quantum dot has a core-shell structure. Examples of materials constituting quantum dots include, but are not limited to, Si; Se; chalcopyrite compounds such as CIGS (CuInGaSe), CIS (CuInSe2), CuInS2, CuAlS2, CuAlSe2, CuGaS2, CuGaSe2, AgAlS2, AgAlSe2, AgInS2, and AgInSe2; perovskite materials; III-V compounds such as GaAs, GaP, InP, InAs, InGaAs, AlGaAs, InGaP, AlGaInP, InGaAsP, and GaN; CdSe, CdSeS, CdS, CdTe, In2Se3, In2S3, Bi2Se3, Bi2S3, ZnSe, ZnTe, ZnS, HgTe, HgS, PbSe, PbS, and TiO2.

[0221] The present disclosure may also be configured as follows. [A01] 《Light-emitting element》 a first compound semiconductor layer having a first surface and a second surface opposite to the first surface; an active layer facing the second surface of the first compound semiconductor layer; and a second compound semiconductor layer having a first surface facing the active layer and a second surface opposite to the first surface; A laminated structure in which a first light reflecting layer formed on the first surface side of the first compound semiconductor layer; a second light reflecting layer formed on the second surface side of the second compound semiconductor layer; a first electrode electrically connected to the first compound semiconductor layer; and a second electrode provided between the second compound semiconductor layer and the second light reflecting layer; Equipped with The second electrode is a light-emitting element having at least a nanocarbon material layer or a two-dimensional material layer. [A02] The light-emitting element according to [A01], wherein the nanocarbon material layer is made of at least one material selected from the group consisting of graphene, carbon nanotubes, and fullerene. [A03] The light-emitting element according to [A01], wherein the two-dimensional material layer is made of at least one material selected from the group consisting of silicene, germanene, boron nitride, and transition metal dichalcogenide-based materials. [A04] A light-emitting element according to [A03], wherein when a transition metal dichalcogenide material is represented by MX2, the transition metal "M" is one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Mo, W, Tc and Re, and the chalcogen element "X" is one element selected from the group consisting of O, S, Se and Te. [A05] The light-emitting element according to any one of [A01] to [A04], wherein the second electrode has a laminated structure of at least a first layer made of a transparent conductive material or a semiconductor material and a second layer made of a nanocarbon material layer or a two-dimensional material layer. [A06] The light-emitting device according to [A05], wherein the first layer is in contact with the second compound semiconductor layer. [A07] The light-emitting device according to [A05] or [A06], wherein the second layer is not formed in the central portion of the second electrode. [A08] The distance from the center of the active layer in the thickness direction of the laminated structure to the center of the nanocarbon material layer or the two-dimensional material layer in the thickness direction is L2, the oscillation wavelength is λ0, and the equivalent refractive index of the part located from the center of the active layer in the thickness direction to the center of the nanocarbon material layer or the two-dimensional material layer in the thickness direction is n eq When 0.9×{(m+1)λ0) / (4 n eq )}≦L2≦1.1×{(m+1)λ0) / (4·n eq )} The light-emitting element according to any one of [A01] to [A06], which satisfies the following: Here, m is an arbitrary integer of 2 or more, including 0 or 1. [A09] The light-emitting element according to any one of [A01] to [A08], wherein the thickness of the nanocarbon material layer or the two-dimensional material layer constituting the second electrode is greater than 0 nm and is 5 nm or less. [A10] At least a portion of the second compound semiconductor layer in the thickness direction is composed of a current injection region and a current non-injection region surrounding the current injection region, The diameter of the current injection region on the second surface of the second compound semiconductor layer is 1×10 -6 m to 1×10 -2 m, preferably 2 x 10 -6 m to 1×10 -3 The light-emitting element according to any one of [A01] to [A09], [A11] The second compound semiconductor layer is partitioned into a first region and a second region surrounding the first region, a second electrode is provided on the first region of the second compound semiconductor layer; The light-emitting device according to any one of [A01] to [A09], wherein the second region of the second compound semiconductor layer faces the second electrode via an insulating layer. [A12] The light-emitting device according to any one of [A01] to [A11], wherein the second electrode has a plurality of grooves formed therein, the grooves extending in one direction. [A13] The first light reflecting layer has a convex shape extending in a direction away from the active layer, The light-emitting device according to any one of [A01] to [A12], wherein the second light reflecting layer has a flat shape. [A14] The radius of curvature of the portion of the first light-reflecting layer having a convex shape is 1×10 -5 m to 1×10 -2 The light-emitting element according to [A13], [A15] The cavity length is 1×10 -6 m to 5×10 -4 The light-emitting element according to [A13] or [A14], [B01] The light-emitting device according to any one of [A01] to [A15], wherein a partition wall extending in the stacking direction of the stacked structure is formed so as to surround the first light reflecting layer. [B02] The light-emitting device according to [B01], wherein the partition wall extends from the first surface side of the first compound semiconductor layer, within the first compound semiconductor layer, to a midpoint in a thickness direction of the first compound semiconductor layer. [B03] The light-emitting device according to [B01], wherein the partition extends from a second surface side of the second compound semiconductor layer into the second compound semiconductor layer and the active layer, and further extends into the first compound semiconductor layer to a midpoint in a thickness direction of the first compound semiconductor layer. [B04] The light-emitting device according to any one of [B01] to [B03], wherein the partition is made of a material that does not transmit light generated in the active layer. [B05] The light-emitting device according to any one of [B01] to [B04], wherein the partition is made of a material that reflects light generated in the active layer. [B06] When the thermal conductivity of the material constituting the first compound semiconductor layer is TC1 and the thermal conductivity of the material constituting the partition wall is TC0, 1×10 -1 ≦TC1 / TC0≦1×10 2 The light-emitting element according to any one of [B01] to [B05], which satisfies the following: [B07] When the linear expansion coefficient of the material constituting the first compound semiconductor layer is CTE1 and the linear expansion coefficient of the material constituting the partition wall is CTE0, |CTE0-CTE1|≦1×10 -4 / K The light-emitting element according to any one of [B01] to [B06], which satisfies the following: [B08] The partition is made of a solder material; The light-emitting element according to any one of [B01] to [B07], wherein a part of the partition is exposed to an outer surface of the light-emitting element. [B09] The light-emitting device according to any one of [B01] to [B08], wherein a side surface of the partition narrows in a direction from the first surface side of the first compound semiconductor layer toward the second surface side of the second compound semiconductor layer. [B10] The first light reflecting layer is formed on a base surface located on the first surface side of the first compound semiconductor layer, The base surface extends to a peripheral region; The light-emitting device according to any one of [B01] to [B09], wherein the base surface is uneven and differentiable. [C01] A base surface located on the first surface side of the first compound semiconductor layer is composed of a first portion and a second portion (peripheral region) surrounding the first portion, a first light reflecting layer formed on the first portion; The light-emitting element according to any one of [A01] to [B10], wherein the first portion is convex and the second portion is concave with respect to the second surface of the first compound semiconductor layer, and the light-emitting element is differentiable from the first portion to the second portion. [C02] The light-emitting element according to [C01], wherein the base surface is smooth. [C03] The light-emitting element according to [C01] or [C02], wherein a first portion of a base surface on which the first light reflecting layer is formed has an upwardly convex shape when the second surface of the first compound semiconductor layer is used as a reference. [C04] 《Light-emitting element of composition A》 The light-emitting device according to [C03], wherein the second portion of the base surface occupying the peripheral region has a downwardly convex shape when the second surface of the first compound semiconductor layer is taken as a reference. [C05] The light-emitting device according to [C04], wherein the center of the first portion of the base surface is located on an apex (intersection) of a square lattice. [C06] The light-emitting device according to [C04], wherein the center of the first portion of the base surface is located on an apex (intersection) of a lattice of equilateral triangles. [C07] 《Light-emitting element of configuration B》 The light-emitting device according to [C03], wherein, when the second surface of the first compound semiconductor layer is used as a reference, the second portion of the base surface occupying the peripheral region has a downwardly convex shape toward a center of the peripheral region, and an upwardly convex shape extending from the downwardly convex shape. [C08] When the distance from the second surface of the first compound semiconductor layer to the center of the first portion of the base surface is LL1 and the distance from the second surface of the first compound semiconductor layer to the center of the second portion of the base surface is LL2, LL2>LL1 The light-emitting element according to [C07], which satisfies the following: [C09] When the radius of curvature of the center of the first portion of the base surface (i.e., the radius of curvature of the first light-reflecting layer) is R1 and the radius of curvature of the center of the second portion of the base surface is R2, R1>R2 The light-emitting element according to [C07] or [C08], which satisfies the following: [C10] The light-emitting device according to any one of [C07] to [C09], wherein the center of the first portion of the base surface is located on an apex (intersection) of a square lattice. [C11] The light-emitting element according to [C10], wherein the center of the second portion of the base surface is located on an apex (intersection) of a square lattice. [C12] The light-emitting device according to any one of [C07] to [C09], wherein the center of the first portion of the base surface is located on an apex (intersection point) of an equilateral triangular lattice. [C13] The light-emitting device according to [C12], wherein the center of the second portion of the base surface is located on an apex (intersection) of a lattice of equilateral triangles. [C14] The radius of curvature R2 at the center of the second part of the base surface is 1×10 -6 m or more, preferably 3×10 -6 m or more, preferably 5×10 -6 The light-emitting element according to any one of [C07] to [C13], wherein m is greater than or equal to [C15]《Light-emitting element of C configuration》 The light-emitting element according to [C03], wherein, when the second surface of the first compound semiconductor layer is taken as a reference, the second portion of the base surface occupying the peripheral region has an annular convex shape surrounding the first portion of the base surface, and a downwardly convex shape extending from the annular convex shape toward the first portion of the base surface. [C16] When the distance from the second surface of the first compound semiconductor layer to the center of the first portion of the base surface is defined as LL1, and the distance from the second surface of the first compound semiconductor layer to the top of the annular convex shape of the second portion of the base surface is defined as LL2', LL2'>LL1 The light-emitting element according to [C15], which satisfies the following: [C17] When the radius of curvature of the center of the first portion of the base surface (i.e., the radius of curvature of the first light-reflecting layer) is R1 and the radius of curvature of the apex of the annular convex shape of the second portion of the base surface is R2', R1>R2' The light-emitting element according to [C15] or [C16], which satisfies the following: [C18] The radius of curvature R2' of the apex of the annular convex shape of the second part of the base surface is 1×10 -6 m or more, preferably 3×10 -6 m or more, preferably 5×10 -6 The light-emitting element according to any one of [C15] to [C17], wherein m is greater than or equal to. [C19] The light-emitting device according to any one of [C07] to [C18], wherein a bump is provided on a portion of the second surface side of the second compound semiconductor layer facing the convex-shaped portion in the second part of the base surface. [C20] The light-emitting device according to any one of [C04] to [C06], wherein a bump is provided on a portion of the second surface side of the second compound semiconductor layer facing the center of the first portion of the base surface. [C21] The light-emitting element according to any one of [C01] to [C20], wherein the formation pitch of the light-emitting elements is 3 μm or more and 50 μm or less, preferably 5 μm or more and 30 μm or less, and more preferably 8 μm or more and 25 μm or less. [C22] The radius of curvature R1 of the center of the first portion of the base surface (i.e., the radius of curvature of the first light-reflecting layer) is 1×10 -4 m or more, preferably 3×10 -4 The light-emitting element according to any one of [C01] to [C21], wherein m is greater than or equal to [C23] The light-emitting device according to any one of [A01] to [C22], wherein the laminated structure is made of at least one material selected from the group consisting of GaN-based compound semiconductors, InP-based compound semiconductors, and GaAs-based compound semiconductors. [C24] Let the cavity length be L OR Then, 1×10 -6 m≦L OR The light-emitting element according to any one of [C01] to [C23], which satisfies the following: [C25] The light-emitting element according to any one of [A01] to [C24], wherein the figure drawn by the first part of the base surface when the base surface is cut by a virtual plane including the stacking direction of the stacked structure is part of a circle or part of a parabola. [C26] The light-emitting device according to any one of [A01] to [C25], wherein the first surface of the first compound semiconductor layer constitutes a base surface. [C27] The light-emitting device according to any one of [A01] to [C25], wherein a compound semiconductor substrate is disposed between the first surface of the first compound semiconductor layer and the first light reflecting layer, and the base surface is composed of a surface of the compound semiconductor substrate. [C28] The light-emitting element according to any one of [A01] to [C25], wherein a base material is disposed between the first surface of the first compound semiconductor layer and the first light reflecting layer, or a compound semiconductor substrate and a base material are disposed between the first surface of the first compound semiconductor layer and the first light reflecting layer, and the base surface is composed of a surface of the base material. [C29] The light-emitting element according to [C28], wherein the material constituting the substrate is at least one material selected from the group consisting of transparent dielectric materials such as TiO2, Ta2O5, SiO2, silicone-based resins, and epoxy-based resins. [C30] The light-emitting device according to any one of [A01] to [C29], wherein a first light-reflecting layer is formed on a base surface. [C31] The light-emitting element according to any one of [A01] to [C30], wherein the thermal conductivity value of the laminated structure is higher than the thermal conductivity value of the first light reflecting layer. [D01] The second compound semiconductor layer is provided with a current injection region and a current non-injection region surrounding the current injection region, The shortest distance D from the center of gravity of the current injection area to the boundary between the current injection area and the non-current injection area CI The light-emitting device according to any one of [A01] to [C31], which satisfies the following formula: D CI ≧ω0 / 2 however, ω0 2 ≡(λ0 / π){L OR (R1-L OR )} 1 / 2 Where: λ0: the wavelength of the desired light mainly emitted from the light-emitting element (oscillation wavelength) L OR :cavity length R1: radius of curvature of the center of the first portion of the base surface (i.e., radius of curvature of the first light-reflecting layer) [D02] A mode loss action portion provided on the second surface of the second compound semiconductor layer and constituting a mode loss action region acting to increase or decrease the oscillation mode loss; a second electrode formed on the second surface of the second compound semiconductor layer and on the mode loss active portion; and a first electrode electrically connected to the first compound semiconductor layer; It further comprises: The second light reflective layer is formed on the second electrode, The laminated structure includes a current injection region and a non-current injection region surrounding the current injection region, The light-emitting device according to [D01], wherein an orthogonal projection image of the mode loss effect region and an orthogonal projection image of the current non-injection region overlap with each other. [D03] The radius r1 of the effective light reflecting area of ​​the first light reflecting layer is ω0≦r1≦20 ω0 The light-emitting element according to [D01] or [D02], which satisfies the following: [D04]D CI The light-emitting element according to any one of [D01] to [D03], which satisfies ≧ω0. [D05] R1≦1×10 -2 The light-emitting element according to any one of [D01] to [D04], which satisfies m. [E01] A mode loss action portion that is provided on the second surface of the second compound semiconductor layer and that constitutes a mode loss action region that acts to increase or decrease the oscillation mode loss; a second electrode formed on the second surface of the second compound semiconductor layer and on the mode loss active portion; and a first electrode electrically connected to the first compound semiconductor layer; It further comprises: The second light reflective layer is formed on the second electrode, The laminated structure includes a current injection region and a non-current injection region surrounding the current injection region, The light-emitting device according to any one of [A01] to [C31], wherein an orthogonal projection image of the mode loss effect region and an orthogonal projection image of the current non-injection region overlap with each other. [E02] The light-emitting device according to [E01], wherein the current non-injection region is located below the mode loss active region. [E03] When the area of ​​the projection image of the current injection region is S1 and the area of ​​the projection image of the current non-injection region is S2, 0.01≦S1 / (S1+S2)≦0.7 The light-emitting element according to [E01] or [E02], which satisfies the following: [E04] The light-emitting device according to any one of [E01] to [E03], wherein the current non-injection region is formed by ion implantation into the laminated structure. [E05] The light-emitting device according to [E04], wherein the ion species is at least one type of ion selected from the group consisting of boron, proton, phosphorus, arsenic, carbon, nitrogen, fluorine, oxygen, germanium, and silicon. [E06] The light-emitting element according to any one of [E01] to [E05], wherein the current non-injection region is formed by irradiating the second surface of the second compound semiconductor layer with plasma, or by performing an ashing treatment on the second surface of the second compound semiconductor layer, or by performing a reactive ion etching treatment on the second surface of the second compound semiconductor layer. [E07] The light-emitting device according to any one of [E01] to [E06], wherein the second light reflecting layer has a region that reflects or scatters light from the first light reflecting layer toward the outside of a resonator structure formed by the first light reflecting layer and the second light reflecting layer. [E08] When the optical distance from the active layer in the current injection region to the second surface of the second compound semiconductor layer is OL2, and the optical distance from the active layer in the mode loss action region to the top surface of the mode loss action portion is OL0, OL0>OL2 The light-emitting element according to any one of [E01] to [E07], which satisfies the following: [E09] The light-emitting device according to any one of [E01] to [E08], wherein the generated light having a higher mode is dissipated by a mode loss effect region toward the outside of a resonator structure formed by the first light reflecting layer and the second light reflecting layer, thereby increasing oscillation mode loss. [E10] The light-emitting device according to any one of [E01] to [E09], wherein the mode loss active portion is made of a dielectric material, a metal material, or an alloy material. [E11] The mode loss active part is made of a dielectric material, The light-emitting element according to [E10], wherein the optical thickness of the mode loss effect portion is a value outside of an integral multiple of ¼ of the wavelength of light generated in the light-emitting element array. [E12] The mode loss active part is made of a dielectric material, The light-emitting element according to [E10], wherein the optical thickness of the mode loss effect portion is an integral multiple of ¼ of the wavelength of the light generated in the light-emitting element array. [E13] A convex portion is formed on the second surface side of the second compound semiconductor layer, The light-emitting device according to any one of [E01] to [E03], wherein the mode loss effect portion is formed on a region of the second surface of the second compound semiconductor layer that surrounds the convex portion. [E14] When the optical distance from the active layer in the current injection region to the second surface of the second compound semiconductor layer is OL2, and the optical distance from the active layer in the mode loss action region to the top surface of the mode loss action portion is OL0, OL0 <OL2 The light-emitting element according to [E13], which satisfies the above. [E15] The light-emitting device according to [E13] or [E14], wherein the generated light having a higher-order mode is confined to the current injection region and the current non-injection region by the mode loss effect region, thereby reducing oscillation mode loss. [E16] The light-emitting device according to any one of [E13] to [E15], wherein the mode loss active portion is made of a dielectric material, a metal material, or an alloy material. [E17] The light-emitting element according to any one of [E01] to [E16], wherein the second electrode is made of a transparent conductive material. [F01] A second electrode formed on a second surface of the second compound semiconductor layer; a second light-reflecting layer formed on the second electrode; a mode loss effect portion that is provided on the first surface of the first compound semiconductor layer and that constitutes a mode loss effect region that acts to increase or decrease the oscillation mode loss; and a first electrode electrically connected to the first compound semiconductor layer; It further comprises: the first light reflecting layer is formed from on the first surface of the first compound semiconductor layer to on the mode loss active portion, The laminated structure includes a current injection region and a non-current injection region surrounding the current injection region, The light-emitting device according to any one of [A01] to [C31], wherein an orthogonal projection image of the mode loss effect region and an orthogonal projection image of the current non-injection region overlap with each other. [F02] When the area of ​​the projection image of the current injection region is S1 and the area of ​​the projection image of the current non-injection region is S2, 0.01≦S1' / (S1'+S2')≦0.7 The light-emitting element according to [F01], which satisfies the following: [F03] The light-emitting device according to [F01] or [F02], wherein the current non-injection region is formed by ion implantation into the laminated structure. [F04] The light-emitting device according to [F03], wherein the ion species is at least one type of ion selected from the group consisting of boron, proton, phosphorus, arsenic, carbon, nitrogen, fluorine, oxygen, germanium, and silicon. [F05] The light-emitting device according to any one of [F01] to [F04], wherein the current non-injection region is formed by irradiating the second surface of the second compound semiconductor layer with plasma, or by performing an ashing treatment on the second surface of the second compound semiconductor layer, or by performing a reactive ion etching treatment on the second surface of the second compound semiconductor layer. [F06] The light-emitting device according to any one of [F01] to [F05], wherein the second light reflecting layer has a region that reflects or scatters light from the first light reflecting layer toward the outside of a resonator structure formed by the first light reflecting layer and the second light reflecting layer. [F07] When the optical distance from the active layer in the current injection region to the first surface of the first compound semiconductor layer is OL1', and the optical distance from the active layer in the mode loss effect region to the top surface of the mode loss effect portion is OL0', OL0'>OL1' The light-emitting element according to any one of [F01] to [F06], which satisfies the following: [F08] The light-emitting device according to any one of [F01] to [F07], wherein the generated light having a higher mode is dissipated by a mode loss effect region toward the outside of a resonator structure formed by the first light reflecting layer and the second light reflecting layer, thereby increasing oscillation mode loss. [F09] The light-emitting device according to any one of [F01] to [F08], wherein the mode loss active portion is made of a dielectric material, a metal material, or an alloy material. [F10] The mode loss active part is made of a dielectric material, The light-emitting element according to [F09], wherein the optical thickness of the mode loss effect portion is a value outside of an integral multiple of ¼ of the wavelength of the light generated in the light-emitting element array. [F11] The mode loss active part is made of a dielectric material, The light-emitting element according to [F09], wherein the optical thickness of the mode loss effect portion is an integral multiple of ¼ of the wavelength of the light generated in the light-emitting element array. [F12] A convex portion is formed on the first surface side of the first compound semiconductor layer, The light-emitting device according to [F01] or [F02], wherein the mode loss effect portion is formed on a region of the first surface of the first compound semiconductor layer that surrounds the convex portion. [F13] When the optical distance from the active layer in the current injection region to the first surface of the first compound semiconductor layer is OL1', and the optical distance from the active layer in the mode loss effect region to the top surface of the mode loss effect portion is OL0', OL0' <OL1’ The light-emitting element according to [F12], which satisfies the above. [F14] A convex portion is formed on the first surface side of the first compound semiconductor layer, The light-emitting device according to [F01] or [F02], wherein the mode loss effect portion is constituted by a region of the first surface of the first compound semiconductor layer surrounding the convex portion. [F15] The light-emitting device according to any one of [F12] to [F14], wherein the generated light having a higher mode is confined to the current injection region and the current non-injection region by the mode loss effect region, thereby reducing oscillation mode loss. [F16] The light-emitting device according to any one of [F12] to [F15], wherein the mode loss active portion is made of a dielectric material, a metal material or an alloy material. [F17] The light-emitting device according to any one of [F01] to [F16], wherein the second electrode is made of a transparent conductive material. [G01] A light-emitting element according to any one of [A01] to [F17], in which at least two light-absorbing material layers are formed in a layered structure including a second electrode parallel to a virtual plane occupied by the active layer. [G02] The light-emitting device according to [G01], wherein at least four light-absorbing material layers are formed. [G03] Let the oscillation wavelength be λ0, the equivalent refractive index of the two light absorbing material layers and the laminated structure between the light absorbing material layers be n eq , the distance between the light absorbing material layers is L Abs When 0.9×{(m λ0) / (2 n eq )}≦L Abs ≦1.1×{(m λ0) / (2 n eq )} The light-emitting element according to [G01] or [G02], which satisfies the following: Here, m is 1 or any integer of 2 or more including 1. [G04] The thickness of the light-absorbing material layer is λ0 / (4·n eq The light-emitting element according to any one of [G01] to [G03], wherein: [G05] The light-emitting device according to any one of [G01] to [G04], wherein the light-absorbing material layer is located at a minimum amplitude portion occurring in a standing wave of light formed inside the laminated structure. [G06] The light-emitting device according to any one of [G01] to [G05], wherein the active layer is located in a maximum amplitude portion of a standing wave of light formed inside the laminated structure. [G07] The light-emitting element according to any one of [G01] to [G06], wherein the light-absorbing material layer has a light absorption coefficient at least twice as high as the light absorption coefficient of the compound semiconductor constituting the laminated structure. [G08] The light-emitting device according to any one of [G01] to [G07], wherein the light-absorbing material layer is composed of at least one material selected from the group consisting of a compound semiconductor material having a narrower band gap than the compound semiconductor constituting the laminated structure, a compound semiconductor material doped with impurities, a transparent conductive material, and a light-reflecting layer constituent material having light-absorbing properties. [H01] 《Method of manufacturing a light-emitting element array》 a first compound semiconductor layer having a first surface and a second surface opposite to the first surface; an active layer facing the second surface of the first compound semiconductor layer; and a second compound semiconductor layer having a first surface facing the active layer and a second surface opposite to the first surface; A laminated structure in which a first light reflecting layer formed on a base surface located on the first surface side of the first compound semiconductor layer; and a second light reflecting layer formed on the second surface side of the second compound semiconductor layer and having a flat shape; Equipped with The base surface extends to a peripheral region surrounded by the plurality of light emitting elements; A method for manufacturing a light-emitting element array including a plurality of light-emitting elements, the base surface of which is uneven and differentiable, the method comprising the steps of: After forming the laminated structure, a second light reflecting layer is formed on the second surface side of the second compound semiconductor layer, and then forming a first sacrificial layer on a first portion of the base surface on which the first light reflecting layer is to be formed, and then forming a convex surface of the first sacrificial layer; forming a second sacrificial layer on a second portion of the base surface exposed between the first sacrificial layer and on the first sacrificial layer to provide an irregular surface of the second sacrificial layer; and The second sacrificial layer and the first sacrificial layer are etched back, and further etched back inward from the base surface, thereby forming a convex portion on the first portion of the base surface and at least a concave portion on the second portion of the base surface when the second surface of the first compound semiconductor layer is used as a reference, and then forming a first light reflective layer over a first portion of the base surface; A method for manufacturing a light-emitting element array comprising each step. [H02] "Method of manufacturing a light-emitting element array" a first compound semiconductor layer having a first surface and a second surface opposite to the first surface; an active layer facing the second surface of the first compound semiconductor layer; and a second compound semiconductor layer having a first surface facing the active layer and a second surface opposite to the first surface; A laminated structure in which a first light reflecting layer formed on a base surface located on the first surface side of the first compound semiconductor layer; and a second light reflecting layer formed on the second surface side of the second compound semiconductor layer and having a flat shape; Equipped with The base surface extends to a peripheral region surrounded by the plurality of light emitting elements; A method for manufacturing a light-emitting element array including a plurality of light-emitting elements, the base surface of which is uneven and differentiable, the method comprising the steps of: After forming the laminated structure, a second light reflecting layer is formed on the second surface side of the second compound semiconductor layer, and then forming a first sacrificial layer on a first portion of the base surface on which the first light reflecting layer is to be formed, and then forming a convex surface of the first sacrificial layer; The first sacrificial layer is etched back, and then etched back from the base surface toward the inside, thereby forming a convex portion on the first portion of the base surface when the second surface of the first compound semiconductor layer is used as a reference, and then forming a second sacrificial layer on the base surface, and then etching back the second sacrificial layer, and then etching back further from the base surface toward the inside, thereby forming a convex portion on the first portion of the base surface and at least a concave portion on the second portion of the base surface when the second surface of the first compound semiconductor layer is used as a reference, and then forming a first light reflective layer over a first portion of the base surface; A method for manufacturing a light-emitting element array comprising each step. [H03] "Method of manufacturing a light-emitting element array" a first compound semiconductor layer having a first surface and a second surface opposite to the first surface; an active layer facing the second surface of the first compound semiconductor layer; and a second compound semiconductor layer having a first surface facing the active layer and a second surface opposite to the first surface; A laminated structure in which a first light reflecting layer formed on a base surface located on the first surface side of the first compound semiconductor layer; and a second light reflecting layer formed on the second surface side of the second compound semiconductor layer and having a flat shape; Equipped with The base surface extends to a peripheral region surrounded by the plurality of light emitting elements; A method for manufacturing a light-emitting element array including a plurality of light-emitting elements, the base surface of which is uneven and differentiable, the method comprising the steps of: Providing a mold having a surface complementary to the base surface; After forming the laminated structure, a second light reflecting layer is formed on the second surface side of the second compound semiconductor layer, and then A sacrificial layer is formed on a base surface on which a first light reflecting layer is to be formed, and then a shape of a surface complementary to the base surface of the mold is transferred to the sacrificial layer to form a concave-convex portion on the sacrificial layer. The sacrificial layer is etched back, and then etched back from the base surface toward the inside, so that, when the second surface of the first compound semiconductor layer is taken as a reference, a convex portion is formed on a first portion of the base surface and at least a concave portion is formed on a second portion of the base surface. forming a first light reflective layer over a first portion of the base surface; A method for manufacturing a light-emitting element array comprising each step. [Explanation of symbols]

[0222] 10A, 10A', 10B, 10C, 10D, 10E, 10F, 10G, 10H... light emitting element (surface emitting element, surface emitting laser element), 11... compound semiconductor substrate (substrate for manufacturing light emitting element array), 20... laminated structure, 21... first compound semiconductor layer, 21a... first surface of first compound semiconductor layer, 21b... second surface of first compound semiconductor layer, 22... second compound semiconductor layer, 22a... first surface of second compound semiconductor layer, 22b... second surface of second compound semiconductor layer, 23... active layer (light emitting layer), 24, 25A, 25B, 25C, 25D... partition wall, 24', 25'... side surface of partition wall, 25D '...part of partition wall, 26...light absorbing material layer, 31...first electrode, 31'...opening provided in first electrode, 32...second electrode, 33...second pad electrode, 34...insulating layer (current confinement layer), 34A...opening provided in insulating layer (current confinement layer), 35...bump, 41...first light reflective layer, 42...second light reflective layer, 48...bonding layer, 49...support substrate, 51...current injection region, 52...current non-injection region, 81, 81'...first sacrificial layer, 82...second sacrificial layer, 83, 83'...part of first sacrificial layer for forming a central portion of second portion, 90...base surface, 90 bd ...boundary between the first portion and the second portion, 91...first portion of the base surface, 91'...projection formed on the first portion of the base surface, 91A...projection formed on the first portion of the base surface, 91 c a central portion of the first portion of the base surface, 92 a second portion of the base surface, 92A a recess formed in the second portion of the base surface, c ...the center of the second portion of the base surface, 92 b 94B...region surrounded by the annular convex shape in the second portion of the base surface; 95...substrate; 96...concave-convex portion for forming the base surface; 97...planarizing film; 99...peripheral region

Claims

1. a first compound semiconductor layer having a first surface and a second surface opposite to the first surface; an active layer facing the second surface of the first compound semiconductor layer; and a second compound semiconductor layer having a first surface facing the active layer and a second surface opposite to the first surface; A laminated structure in which A first light reflecting layer formed on the first surface side of the first compound semiconductor layer; a second light reflecting layer formed on the second surface side of the second compound semiconductor layer; a first electrode electrically connected to the first compound semiconductor layer; and a second electrode provided between the second compound semiconductor layer and the second light reflecting layer; It is equipped with The second electrode is a light emitting device having at least a two-dimensional layer of material.

2. The second electrode further has a nanocarbon material layer, The light-emitting device according to claim 1 , wherein the nano-carbon material layer is made of at least one material selected from the group consisting of graphene, carbon nanotubes, and fullerene.

3. 10. The light-emitting device of claim 1, wherein the two-dimensional material layer is made of at least one material selected from the group consisting of silicene, germanene, boron nitride, and transition metal dichalcogenide-based materials.

4. Transition metal dichalcogenide materials are 2 wherein the transition metal "M" is one element selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Mo, W, Tc and Re, and the chalcogen element "X" is one element selected from the group consisting of O, S, Se and Te.

5. The light-emitting element according to claim 1 , wherein the second electrode has a laminated structure of at least a first layer made of a transparent conductive material or a semiconductor material and a second layer made of a two-dimensional material layer.

6. The light emitting device according to claim 5 , wherein the first layer is in contact with the second compound semiconductor layer.

7. The light-emitting element according to claim 5 , wherein the second layer is not formed in a central portion of the second electrode.

8. The distance from the center of the active layer in the thickness direction of the laminated structure to the center of the two-dimensional material layer in the thickness direction is L ２ , the oscillation wavelength is λ ０ , the equivalent refractive index of the part located from the center of the active layer in the thickness direction to the center of the two-dimensional material layer in the thickness direction is n ｅｑ When 0.9×{(m+1)λ ０ ) / (4・. ｅｑ )}≦L ２ ≦1.1×{(m+1)λ ０ ) / (4・. ｅｑ )} The light emitting device according to claim 1 , which satisfies the following: Here, m is an arbitrary integer of 2 or more, including 0 or 1.

9. The light-emitting device according to claim 1 , wherein the thickness of the two-dimensional material layer constituting the second electrode is greater than 0 nm and is not greater than 5 nm.

10. At least a portion of the second compound semiconductor layer in a thickness direction is composed of a current injection region and a current non-injection region surrounding the current injection region, The diameter of the current injection region in the second surface of the second compound semiconductor layer is 1×10 －６ m to 1×10 －２ The light-emitting device according to claim 1 , wherein m is a valence number of 1 to 5.

11. the second compound semiconductor layer is partitioned into a first region and a second region surrounding the first region; a second electrode is provided on the first region of the second compound semiconductor layer; The light-emitting device according to claim 1 , wherein the second region of the second compound semiconductor layer faces the second electrode via an insulating layer.

12. The light emitting element according to claim 1 , wherein the second electrode has a plurality of grooves formed therein and extending in one direction.

13. the first light reflecting layer has a convex shape extending in a direction away from the active layer, The light-emitting device according to claim 1 , wherein the second light-reflecting layer has a flat shape.

14. The radius of curvature of the portion of the first light reflecting layer having a convex shape is 1×10 -5 m to 1×10 -2 The light-emitting device according to claim 13, wherein m is a 1-methyl-1-propanediol group.

15. The cavity length is 1×10 －６ m to 5×10 －４ The light-emitting device according to claim 13, wherein m is a 1-methyl-1-propanediol group.

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