Light emitting element and image display device

Abstract

According to one embodiment of the present disclosure, a light-emitting element is provided with: a semiconductor layer, having a first surface and a second surface, and formed by a stack of a first conductive type layer, an active layer, and a second conductive type layer in sequence from the first surface side; a first dielectric layer, provided on the second surface side of the semiconductor layer and having an opening; a first electrode, electrically coupled to the first conductive type layer on the first surface side of the semiconductor layer; and a second electrode, provided on the first dielectric layer and electrically coupled to the second conductive type layer via the opening.

Description

Technical Field

[0001] The present disclosure relates to a light emitting element that emits light in a stacking direction of semiconductors and an image display device including the light emitting element. Background Art

[0002] In recent years, lighting devices or image display devices configured by collecting a plurality of light-emitting elements such as light-emitting diodes (LEDs) have become popular. Among them, LED displays using LEDs as display pixels have attracted attention as light and thin displays, and various improvements such as improving luminous efficiency have been made.

[0003] For example, Patent Document 1 discloses a light-emitting element including a configuration in which a semiconductor layer and a contact layer are stacked. The semiconductor layer has a first conductive type layer, an active layer, and a second conductive type layer. The light-emitting element improves light extraction efficiency in a forward direction by providing an insulating layer including a transparent material having a predetermined refractive index on the contact layer, the contact layer being formed on the light extraction surface side.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2016-4892 Summary of the invention

[0007] Incidentally, in a light emitting element constituting a lighting device or a display device, compatibility between connectivity with a conductive electrode and light extraction efficiency is required.

[0008] It is desirable to provide a light emitting element and an image display device that allow compatibility between connectivity with a conductive electrode and light extraction efficiency.

[0009] According to one embodiment of the present disclosure, a light-emitting element includes: a semiconductor layer having a first surface and a second surface, and including a first conductive type layer, an active layer, and a second conductive type layer stacked in sequence from the first surface side; a first dielectric layer, arranged on the second surface side of the semiconductor layer and having an opening; a first electrode, electrically coupled to the first conductive type layer on the first surface side of the semiconductor layer; and a second electrode, arranged on the first dielectric layer and electrically coupled to the second conductive type layer via the opening.

[0010] An image display device according to one embodiment of the present disclosure includes the above-described light emitting element according to one embodiment as a plurality of light emitting elements.

[0011] In a light-emitting element according to an embodiment of the present disclosure and an image display device according to an embodiment of the present disclosure, a first dielectric layer having an opening is provided on the second surface side of a semiconductor layer in which a first conductive type layer, an active layer, and a second conductive type layer are stacked, and the second conductive type layer and a second electrode provided on the first dielectric layer are electrically coupled to each other via the opening. Therefore, for example, the formation area of ​​the second electrode can be reduced while increasing the margin for positional deviation between an external wiring provided on, for example, the light-emitting element and the second electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1A A schematic cross-sectional view (A) and a schematic plan view (B) illustrating an example of a configuration of a light emitting element according to a first embodiment of the present disclosure are included.

[0013] Figure 1B is a schematic cross-sectional view showing another example of the configuration of the light emitting element according to the first embodiment of the present disclosure.

[0014] Figure 1C is a schematic cross-sectional view showing another example of the configuration of the light emitting element according to the first embodiment of the present disclosure.

[0015] Figure 2A is to show the external wiring and Figure 1A A schematic plan view of an example of coupling of light emitting elements is shown.

[0016] Figure 2B It is shown Figure 2A Schematic cross-sectional view showing the configuration of a light emitting element and external wiring.

[0017] Figure 3A is to show the external wiring and Figure 1A A schematic plan view of another example of coupling of light emitting elements is shown.

[0018] Figure 3B It is shown Figure 3A Schematic cross-sectional view showing the configuration of a light emitting element and external wiring.

[0019] Figure 4A It is shown that multiple Figure 1A A perspective view of an example of a configuration of a light emitting unit of a light emitting element is shown.

[0020] Figure 4B It is shown Figure 4A Schematic diagram of the cross-sectional configuration of the light-emitting unit shown.

[0021] Figure 5 Included are a schematic cross-sectional view (A) and a schematic plan view (B) showing an example of a configuration of a general light emitting element.

[0022] Figure 6 A schematic cross-sectional view (A) and a schematic plan view (B) illustrating an example of a configuration of a light emitting element according to a second embodiment of the present disclosure are included.

[0023] Fig. 7A is a schematic cross-sectional view showing an example of a configuration of a light emitting element according to a third embodiment of the present disclosure.

[0024] Figure 7B It is shown Fig. 7A A schematic plan view of the light-emitting element shown.

[0025] Figure 8 : is a schematic plan view showing an example of the configuration of a light emitting element according to a modification example of the present disclosure.

[0026] Fig. 9 As an application example, a configuration is shown. Figure 1A A perspective view of an example of a configuration of a display device of a light emitting element shown in FIG.

[0027] Fig.10 It is shown Fig. 9 A schematic diagram of an example of a layout of a display device is shown.

[0028] Fig.11A 1 is a plan view showing an example of a lighting device as an application example.

[0029] Fig. 11B It is shown Fig.11A A perspective view of the lighting device shown.

[0030] Fig. 12A is a plan view showing another example of the lighting device as an application example.

[0031] Fig. 12B It is shown Fig. 12A A perspective view of the lighting device shown.

[0032] Fig.13A is a plan view showing another example of the lighting device as an application example.

[0033] Fig. 13B It is shown Fig.13A A perspective view of the lighting device shown. DETAILED DESCRIPTION

[0034] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The following description is a specific example of the present disclosure, but the present disclosure is not limited to the following embodiments. In addition, the present disclosure is not limited to the arrangement, size, size ratio, etc. of the constituent elements shown in the accompanying drawings. It should be noted that the description is given in the following order.

[0035] 1. First Embodiment (Example in which a dielectric layer is provided on a second conductive type layer and the second conductive type layer and a second electrode are electrically coupled to each other through an opening provided on the dielectric layer)

[0036] 1-1. Arrangement of light-emitting elements

[0037] 1-2. Configuration of light-emitting units

[0038] 1-3. Work and Effect

[0039] 2. Second Embodiment (Example in which the Second Electrode Has a Single-Layer Structure)

[0040] 3. Third Embodiment (Example in which the Concavo-convex Structure is Provided Around the Second Electrode)

[0041] 4. Modification (Example in which the second electrode is arranged on a diagonal line of the light extraction surface)

[0042] 5. Application examples

[0043] <1. First Embodiment>

[0044] Figure 1A (A) schematically shows a cross-sectional configuration of a light emitting element (light emitting element 10) according to a first embodiment of the present disclosure, and Figure 1A (B) schematically shows Figure 1A The planar configuration of the light emitting element 10 shown in (A) is shown. Note that Figure 1A (A) indicates along Figure 1A The light emitting element 10 is an LED chip and is suitable for use as an image display device (eg, a display device 2 (see FIG. 1 )) called a so-called LED display. Fig. 9 ))'s display pixels.

[0045] The light emitting element 10 has a semiconductor layer 11 (semiconductor layer) in which a first conductive type layer 12, an active layer 13, and two layers including, for example, a second conductive type layer 14 and a second conductive type layer 15 are stacked in this order. The lower surface of the first conductive type layer 12 is the back surface (surface S1; first surface) of the semiconductor layer 11, and the upper surface of the second conductive type layer 15 is the light extraction surface (surface S2; second surface) of the semiconductor layer 11. Figure 1AAs shown in (A), the side surface (surface S3) of the light-emitting element 10 has an inclined surface that intersects with the stacking direction (Y-axis direction) of each layer. Specifically, the cross-section of the light-emitting element 10 is an inverted trapezoidal shape. The light-emitting element 10 has a first electrode 21 on the surface S1 side of the semiconductor layer 11, and a second electrode 22 on the surface S2 side of the semiconductor layer 11. In the light-emitting element 10 of the present embodiment, the dielectric layer 19 (first dielectric layer) is disposed on the second conductive type layer 15 of the semiconductor layer 11, and the second conductive type layer 15 and the second electrode 22 are electrically coupled to each other through an opening 19H disposed on the dielectric layer 19. On the side surface (surface S3) of the semiconductor layer 11 and the lower surface (surface S1) of the semiconductor layer 11, a laminated film stacked with a dielectric layer 16, a metal layer 17, and a dielectric layer 18 is disposed. The first electrode 21 is electrically coupled to the first conductive type layer 12 via an opening 16H disposed on the laminated film.

[0046] (1-1. Arrangement of Light Emitting Elements)

[0047] The light emitting element 10 is a solid-state light emitting element that emits light of a predetermined waveform from an upper surface (light extraction surface; surface S2). Specifically, the light emitting element 10 is an LED (light emitting diode) chip. The LED chip refers to a state in which the LED chip is cut out from a wafer for crystal growth, rather than a package type covered with a molding resin or the like. The size of the LED chip is, for example, greater than 5 μm and less than 100 μm, and is a so-called micro-LED. The planar shape of the LED chip is, for example, substantially square. The LED chip is in the form of a sheet. In order to prevent light from being absorbed, the aspect ratio (height / width) of the LED chip is, for example, preferably 0.1 or greater and less than 1.

[0048] Hereinafter, respective members constituting the light emitting element 10 will be described.

[0049] According to the light of the desired wavelength band, the materials of the first conductive type layer 12, the active layer 13, and the second conductive type layer 14 and the second conductive type layer 15 constituting the semiconductor layer are appropriately selected. Specifically, in the case of obtaining light of the red wavelength band, it is preferable to use, for example, an AlGaInP-based semiconductor material. Specifically, in the case of obtaining light of the blue wavelength band or the green wavelength band, it is preferable to use, for example, an AlGaInN-based semiconductor material.

[0050] The first conductive type layer 12 is electrically coupled to the first electrode 21 and includes, for example, n-type AlGaInP. The active layer 13 has, for example, a multi-quantum well structure including a well layer and a barrier layer, each of which is configured by semiconductors having different compositions from each other and configured to emit light of a predetermined wavelength. The active layer 13 according to the present embodiment is capable of emitting, for example, red light having an emission wavelength of 500 nm or more and 700 nm or less. The active layer 13 includes, for example, about 3 to 20 layers of well layers containing GaInP and about 2 to 19 layers of barrier layers containing AlGaInP, and the well layers and the barrier layers are stacked on each other. For example, for blue and green light emission, the first conductive type layer 12 preferably includes n-type AlGaInN, and the active layer 13 preferably includes, for example, about 1 to 20 layers of well layers containing GaInN and about 0 to 19 layers of barrier layers containing GaInN. Light having an emission wavelength of, for example, 400 nm or more and 600 nm or less can be emitted.

[0051] The second conductive type layer 14 is formed on the active layer 13 and includes, for example, p-type AlGaInP. The second conductive type layer 15 is disposed on the second conductive type layer 14 and is electrically coupled to the second electrode 22. In a plan view, the second conductive type layer 15 is disposed on the entire light extraction surface (surface S2) of the semiconductor layer 11, and the area where the second electrode 22 is not formed constitutes the light extraction area of ​​the light emitting element 10. The second conductive type layer 15 preferably includes a material capable of ohmic contact with the second electrode 22, and includes, for example, p-type GaP. For example, in the case of blue and green light emission, the second conductive type layer 14 preferably uses a layer containing n-type AlGaInN, and the second conductive type layer 15 preferably uses a layer containing p-type GaInN.

[0052] The dielectric layer 16 is used to electrically insulate the metal layer 17 from the semiconductor layer 11. The dielectric layer 16 is provided on the entire side surface (surface S3) of the semiconductor layer 11, and is further provided to cover the peripheral portion of the surface of the contact portion 21A constituting the first electrode 21. As the material of the dielectric layer 16, a material capable of transmitting light emitted from the active layer 13 is preferably used. For example, silicon oxide (SiO x ), Silicon Nitride (SiN x ), aluminum oxide (AlO x ), titanium oxide (TiO x ), titanium nitride (TiN), etc. The thickness of the dielectric layer 16 is, for example, about 0.1 μm to 1 μm, and is substantially uniform according to the film forming direction. Note that the thickness of the dielectric layer 16 may have non-uniformity caused by manufacturing errors. In addition, since the film of the semiconductor wafer is generally formed from the upper side or the lower side, the dielectric layer 16 formed on the side surface (surface S3) of the semiconductor layer 11 tends to have a thin film thickness.

[0053] The metal layer 17 is used to shield or reflect the light emitted from the active layer 13. The metal layer 17 is formed to contact the surface of the dielectric layer 16. For example, the end of the metal layer 17 on the light extraction surface S2 side is formed on the same surface as the light extraction surface S2 side of the second conductive type layer 15. At the same time, the end of the metal layer 17 on the second electrode 22 side is formed, for example, near the end of the first electrode 21, with the dielectric layer 16 interposed therebetween. That is, the metal layer 17, the semiconductor layer 11, the second electrode 22 and the first electrode 21 are insulated and separated (electrically separated) by the dielectric layer 16. As the material of the metal layer 17, it is preferable to use a material that shields or reflects the light emitted from the active layer 13. For example, titanium (Ti), aluminum (Al), copper (Cu), gold (Au), silver (Ag) or nickel (Ni) or an alloy thereof can be used. The thickness of the metal layer 17 is, for example, about 0.1 μm to 1 μm, and is substantially uniform according to the film formation direction. Note that the thickness of the metal layer 17 may have unevenness caused by manufacturing errors. Furthermore, since a semiconductor wafer is generally formed from the upper side or the lower side, the metal layer 17 formed on the side surface (surface S3) of the semiconductor layer 11 tends to have the same film thickness as that of the dielectric layer 16. In addition, depending on different manufacturing methods, the metal layer 17 may have a thickness such as Figure 1A The structure surrounded by dielectric layer 19, dielectric layer 16 and dielectric layer 18 is shown, and is located at the junction of dielectric layer 19, dielectric layer 16 and dielectric layer 18 (the intersection of surface S2 and surface S3), but according to different manufacturing methods, a part of it can be exposed.

[0054] The dielectric layer 18 is intended to be used when the light emitting element 10 is mounted on a circuit board for mounting (for example, a wiring substrate 52 (see Figure 2B )) prevents the conductive material (for example, solder, plated or sputtered metal) and the metal layer 17 from short-circuiting each other. The conductive material joins the pad portion 21B constituting the first electrode 21 and the substrate for mounting to each other. The dielectric layer 18 is formed to contact the surface of the metal layer 17 and the surface of the dielectric layer 16 covering the periphery of the contact portion 21A of the first electrode 21. The dielectric layer 18 is formed on the entire surface of the metal layer 17 and is formed on all or part of the dielectric layer 16. As a material for the dielectric layer 18, a material similar to that of the dielectric layer 16 can be used. For example, silicon oxide (SiO x ), Silicon Nitride (SiN x ), aluminum oxide (AlO x ), titanium oxide (TiO x), titanium nitride (TiN), etc. In addition, the dielectric layer 18 may include a plurality of the above materials. The thickness of the dielectric layer 18 is, for example, about 0.1 μm to 1 μm, and is substantially uniform according to the film forming direction. Note that the thickness of the dielectric layer 18 may have non-uniformity caused by manufacturing errors. In addition, since the semiconductor wafer is generally formed from the upper side or the lower side, the dielectric layer 18 formed on the side surface (surface S3) of the semiconductor layer 11 tends to have the same film thickness as that of the dielectric layer 16 and the metal layer 17.

[0055] The dielectric layer 19 is provided on the second conductive type layer 15 for protecting the semiconductor layer 11 (specifically, the surface of the second conductive type layer 15) and for improving the light emission intensity in the forward direction of the light emitting element 10. As will be described in detail later, the dielectric layer 19 has an opening 19H so as to expose a contact portion 22A constituting, for example, a second electrode 22 provided directly on the second conductive type layer 15. A portion near the opening 19H is formed on the contact portion 22A to cover the periphery of the contact portion 22A.

[0056] As the material of the dielectric layer 19, it is preferable to have a light-transmitting property and a refractive index difference of 0.3 or more from the second conductive type layer 15, more preferably 1.0 or more and smaller than the refractive index of the second conductive type layer 15. Examples of such materials include aluminum oxide (Al x O y ), silicon oxide (SiO x ) and silicon nitride (Si x N y ). The dielectric layer 19 is configured as a single layer film or a laminated film including the above materials. Alternatively, titanium oxide (TiO x ), titanium nitride (TiN), etc. can be used as the dielectric layer 19. Therefore, the luminous intensity in the forward direction can be improved while ensuring the insulation of the light extraction surface (surface S1) of the light emitting element 10. The thickness of the dielectric layer 19 is preferably 100 μm or more and 800 μm or less, more preferably 400 μm or more and 600 μm or less, and is substantially uniform. Note that the thickness of the dielectric layer 19 may have non-uniformity caused by manufacturing errors.

[0057] The first electrode 21 is electrically coupled to the lower surface (surface S1) of the semiconductor layer 11 (i.e., electrically coupled to the first conductive type layer 12). That is, the first electrode 21 is in ohmic contact with the first conductive type layer 12, and is formed as an n-electrode, for example. The first electrode 21 is configured by, for example, a contact portion 21A directly provided on the first conductive type layer 12 and a pad portion 21B provided on the dielectric layer 16 and the dielectric layer 18. The pad portion 21B is electrically coupled to the contact portion 21A through the opening 16H provided on the dielectric layer 16.

[0058] The first electrode 21 is a metal electrode and is configured as a multilayer electrode of titanium (Ti) / platinum (Pt) / gold (Au) or an alloy of gold and germanium (AuGe) / Ni (nickel) / Au, for example. In addition, the first electrode 21 may include a highly reflective metal material such as silver (Ag) or aluminum (Al). The contact portion 21A and the pad portion 21B constituting the first electrode 21 may include the same material as each other, but from the perspective of making ohmic contact with GaAs constituting the first conductive type layer 12, the contact portion 21A preferably uses, for example, AuGeNi / Au. From the perspective of subsequent wiring connection, the pad portion 21B preferably includes, for example, TiPtAu.

[0059] In addition, for example, Figure 1B As shown, the contact portion 21A can be formed as a laminated film including a contact layer 21A1 and a metal layer 21A2. As the contact layer 21A1, it is preferred to use a material that allows ohmic contact with the first conductive type layer 12. For example, an n-type GaAs material or the like can be used. For the metal layer 21A2, gold (Au), germanium (Ge) and nickel (Ni) are preferably used. In this way, a laminated film of the contact layer 21A1 and the metal layer 21A2 is used as the contact portion 21A, so that it is possible to avoid light absorption by a semiconductor material such as n-type GaAs constituting the contact layer 21A1 while allowing ohmic contact with the first conductive type layer 12.

[0060] The second electrode 22 is provided on the light extraction surface (surface S1) side. The second electrode 22 is in contact with the second conductive type layer 15 and is electrically coupled to the second conductive type layer 15. That is, the second electrode 22 is in ohmic contact with the second conductive type layer 15 and is formed as a p-electrode, for example. Figure 1A As shown in (B), the second electrode 22 has, for example, a planar shape that is longer in the horizontal direction, the aspect ratio of which is 1 or greater, more preferably 2 or greater, and has a long side direction and a short side direction. Here, the long side direction is the X-axis direction, and the short side direction is the Z-axis direction. Specifically, the second electrode 22 has a substantially symmetrical structure, which includes: a connecting portion 22X, which is, for example, substantially circular at a position corresponding to the opening 19H; and an extension portion 22Y, which extends in directions opposite to each other, and the connecting portion 22X is located therebetween, and the width of the extension portion 22Y is smaller than the diameter of the connecting portion 22X. In addition, the second electrode 22 of the present embodiment is configured by, for example, a contact portion 22A directly disposed on the second conductive type layer 15 and a pad portion 22B disposed on the dielectric layer 19.

[0061] The contact portion 22A is formed in a substantially circular shape, for example, just above the second conductive type layer 15. Figure 1AAs shown, for example, in the case where the first conductive type layer 12 and the contact portion 21A do not absorb the light emitted from the active layer 13, the size (a1) of the contact portion 22A in the uniaxial direction (e.g., the X-axis direction) is preferably equal to or smaller than the size (b1) of the contact portion 21A of the first electrode 21 in the uniaxial direction (e.g., the X-axis direction) (a1≤b1). In addition, for example, in the case where one or both of the first conductive type layer 12 and the contact portion 21A absorb the light emitted from the active layer 13, for example, as Figure 1C As shown, in the uniaxial direction (for example, the X-axis direction) of the contact portion 21A of the above-mentioned first electrode 21, it is preferred that the dimension (a1) is equal to or greater than the dimension (b1) (a1≥b1). In this case, absorption refers to the absorption of energy whose band gap of the semiconductor is less than the emission wavelength, and does not include the absorption of free carriers or dopants. The pad portion 22B is electrically coupled to the contact portion 22A through the opening 19H provided on the dielectric layer 19. The pad portion 22B constitutes the planar shape of the above-mentioned second electrode 22. In a plan view, the pad portion 22B has a shape that is longer in the horizontal direction, and the aspect ratio of the shape is, for example, 1 or greater, more preferably 2 or greater, wherein the X-axis direction is the long side direction thereof, and the Z-axis direction is the short side direction thereof. The pad portion 22B has a connecting portion 22X in its middle portion and an extension portion 22Y at both ends thereof. That is, the pad portion 22B has a substantially symmetrical structure with the opening 19H interposed therebetween. The connection portion 22X covers the opening 19H of the dielectric layer 19 and is coupled to the contact portion 22A. The extension portion 22Y is used to ensure that the second electrode 22 is electrically coupled to the wiring 51 described later (for example, refer to Figure 2A ). In addition, the minimum diameter of the pad portion 22B ( Figure 1A The width in the Z-axis direction) is preferably smaller than the minimum diameter of the pad portion 21B of the first electrode 21 (eg, the width in the Z-axis direction).

[0062] The second electrode 22 is a metal electrode. The second electrode 22 includes, for example, titanium (Ti), platinum (Pt), aluminum (Al), gold (Au), rhodium (Ph) and copper (Cu), or is configured as a multilayer thereof. The contact portion 22A and the pad portion 22B constituting the second electrode 22 can be formed using the same material as each other. However, from the viewpoint of semiconductor connection, the contact portion 22A is preferably formed using, for example, titanium (Ti), platinum (Pt), aluminum (Al) and gold (Au), and from the viewpoint of wiring connection and light reflection, the pad portion 22B is preferably formed using, for example, titanium (Ti), platinum (Pt), aluminum (Al), gold (Au), rhodium (Ph) and copper (Cu).

[0063] Figure 2AThe connection example between the light emitting element 10 of this embodiment and the external wiring (wiring 51) is schematically shown in a plan view. For example, the external wiring is used to control the driving of a plurality of light emitting elements 10 arranged in the display device 2 described later. Figure 2B Schematically shows Figure 2A Cross-sectional configuration. Figure 3A Another example of connection between the light emitting element 10 of this embodiment and external wiring (wiring 51) is schematically shown in a plan view. For example, the external wiring is used to control driving of a plurality of light emitting elements 10 arranged in a display device 2 described later. Figure 3B Schematically shows Figure 3A In this embodiment, by extending the wiring 51 ( Figure 2A By arranging the light emitting element 10 in the Z-axis direction (for example, the X-axis direction) so that the long side direction (for example, the X-axis direction) of the pad portion 22B constituting the second electrode 22 intersects with the extending direction of the wiring 51, the margin for positional deviation between the second electrode 22 and the wiring 51 can be increased. Figure 2B As shown, the first electrode 21 is joined to the wiring substrate 52 for n-electrode connection by, for example, plating or soldering.

[0064] (1-2. Configuration of light-emitting unit)

[0065] Figure 4A is a perspective view of an example of a schematic configuration of the light emitting unit 1 . Figure 4B Shown along Figure 4A An example of a cross-sectional configuration of the light emitting unit 1 taken along line II-II in FIG. The light emitting unit 1 is suitably used as a display pixel of a display device 2 described later, for example, and is a micro package of a plurality of light emitting elements 10 covered with a thin thickness of resin.

[0066] In the light emitting unit 1, the light emitting element 10 is arranged in a row with another light emitting element 10 and has a predetermined gap therebetween. The light emitting unit 1 has, for example, an elongated structure extending in the arrangement direction of the light emitting elements 10. The gap between two light emitting elements 10 adjacent to each other is, for example, equal to or greater than the size of each light emitting element 10. In some cases, the gap may be narrower than the size of each light emitting element 10.

[0067] Each light emitting element 10 emits light of different wavelength bands. Figure 4AAs shown, the three light emitting elements 10 are configured by a light emitting element 10G emitting light in the green band, a light emitting element 10R emitting light in the red band, and a light emitting element 10B emitting light in the blue band. For example, in the case where the light emitting unit 1 has an elongated shape extending in the arrangement direction of the light emitting elements 10, the light emitting element 10G is arranged near the short side of the light emitting unit 1, and the light emitting element 10B is arranged, for example, near the short side of the light emitting unit 1, which is different from the short side near which the light emitting element 10G is located. The light emitting element 10R is arranged, for example, between the light emitting element 10G and the light emitting element 10B. Note that although each position of the light emitting element 10R, the light emitting element 10G, and the light emitting element 10B is not limited to the above position, in the following, sometimes the positional relationship of other components may be described on the premise that the light emitting element 10R, the light emitting element 10G, and the light emitting element 10B are arranged in the respective positions exemplified above.

[0068] like Figure 4A and Figure 4B As shown, the light emitting unit 1 further includes a chip-type insulator 40 covering each light emitting element 10, and terminal electrodes 31 and 32 electrically coupled to each light emitting element 10. The terminal electrodes 31 and 32 are provided at the bottom surface side of the insulator 40.

[0069] The insulator 40 holds and surrounds each light emitting element 10 from at least the side surface of each light emitting element 10 to a portion of its upper surface, and has an opening 40H1 on each light emitting element 10. The insulator 40 includes, for example, a resin material such as silicon, acryl or epoxy. The insulator 40 may partially include another material such as polyimide. The insulator 40 has an elongated shape (for example, a rectangular shape) extending in the arrangement direction of each light emitting element 10. The height of the insulator 40 is greater than the height of each light emitting element 10, and the lateral width (width in the short side direction) of the insulator 40 is greater than the width of each light emitting element. The insulator 40 itself has, for example, a size of 1 mm or less. The insulator 40 is in the form of a thin sheet. The aspect ratio (maximum height / maximum lateral width) of the insulator 40 is small enough so that the light emitting unit 1 does not lie down when the light emitting unit 1 is transferred. For example, the aspect ratio (maximum height / maximum lateral width) is 1 / 5 or less.

[0070] For example, Figure 4B As shown, the insulator 40 has openings 40H2 at positions corresponding to positions directly below each light emitting element 10. At least the above-mentioned pad portion 21B ( Figure 4BThe pad portion 21B is coupled to the terminal electrode 31 via, for example, a predetermined conductive member (e.g., solder, plated metal). The bump 33 is a columnar conductive member embedded in the insulator 40. For example, the connection portion 34 is a strip-shaped conductive member formed on the surface of the insulator 40 and is connected to the terminal electrode 31 via, for example, a predetermined conductive member (e.g., solder, plated metal). Figure 2A and Figure 2B The illustrated wiring 51 corresponds. The terminal electrodes 31 and 32 mainly include titanium (Ti) and copper (Cu), for example. Portions of the surfaces of the terminal electrodes 31 and 32 may be coated with a material that is difficult to oxidize, such as Au (gold).

[0071] (1-3. Work and Effect)

[0072] Next, the operation and effects of the light emitting element 10 according to the present embodiment will be described.

[0073] As described above, LED displays using LEDs as display pixels have attracted attention as light and thin displays, and various improvements such as improving luminous efficiency have been made. As a method of improving luminous efficiency, for example, in a configuration of a semiconductor layer stacked with a first conductive type layer, an active layer, a second conductive type layer, and a contact layer, an insulating layer including a transparent material having a predetermined refractive index is provided on a contact layer serving as a light extraction surface, thereby improving light extraction efficiency in the forward direction. Therefore, the luminous intensity in the forward direction can be increased and the luminous efficiency can be improved.

[0074] Figure 5 (A) schematically shows a cross-sectional configuration of a typical light emitting element 1000 , and Figure 5 (B) schematically shows Figure 5 (A) shows a planar configuration of the light emitting element 1000. Note that Figure 5 (A) shows along Figure 5 1014. A cross section taken along line III-III shown in (B) of FIG. 1015. In a conventional light emitting element 1000, a p-electrode 1022 is provided on a contact layer 1015 stacked on a semiconductor layer 1011, the semiconductor layer 1011 including a first conductive type layer 1012, an active layer 1013, and a second conductive type layer 1014, and an n-electrode 1021 is provided on a lower surface of the semiconductor layer 1011. Note that a laminated film in which a dielectric layer 1016, a metal layer 1017, and a dielectric layer 1018 are stacked in this order is formed on the side surfaces of the semiconductor layer 1011 and the contact layer 1015 and on the lower surface of the semiconductor layer 1011.

[0075] In the light emitting element 1000, the dielectric layer 1019 is provided outside the formation region of the p-electrode 1022 on the contact layer 1015, and a portion of the dielectric layer 1019 is provided to cover the periphery of the contact layer 1015. Therefore, in an LED display in which a plurality of light emitting elements 1000 are arranged, when an external wiring for controlling the driving of the light emitting elements 1000 arranged in each display pixel is coupled to the p-electrode 1022, the external wiring crosses over a stacked portion including the p-electrode 1022 and the dielectric layer 1019. Therefore, the p-electrode 1022 needs to be formed large to ensure coupling with the external wiring, which may result in shielding and absorption of light and thus reduce light extraction efficiency.

[0076] In contrast, according to the present embodiment, the second electrode 22 electrically coupled to the second conductive type layer 15 on the light extraction surface (surface S2) side of the semiconductor layer 11 is configured by a contact portion 22A directly provided on the second conductive type layer 15 and a pad portion 22B provided on the dielectric layer 19 on the second conductive type layer 15. The contact portion 22A and the pad portion 22B are coupled via an opening 19H provided on the dielectric layer 19 corresponding to the contact portion 22A. Therefore, the formation area of ​​the second electrode 22 formed on the second conductive type layer 15 (specifically, the formation area of ​​the contact portion 22A directly formed on the second conductive type layer 15) can be reduced, and the reflection area derived from the dielectric layer 19 can be increased.

[0077] As described above, the light emitting element 10 according to the present embodiment includes the dielectric layer 19 having the opening 19H at a predetermined position on the second conductive type layer 15 constituting the light extraction surface (surface S2) of the semiconductor layer 11, and the second electrode 22 electrically coupled to the second conductive type layer 15 via the opening 19H is provided on the dielectric layer 19. Specifically, as the second electrode 22, the contact portion 22A which ensures electrical coupling with the second conductive type layer 15 is provided on the second conductive type layer 15, and the pad portion 22B electrically coupled to the contact portion 22A via the opening 19H provided on the contact portion 22A is provided on the dielectric layer 19. Therefore, the formation area where the second electrode 22 (specifically, the contact portion 22A) is directly formed on the second conductive type layer 15 can be reduced, and the reflection area derived from the dielectric layer 19 can be increased. That is, the light extraction efficiency can be improved while ensuring connectivity with the conductive electrode (wiring 51).

[0078] In addition, in the present embodiment, the second electrode 22 is composed of two members including a contact portion 22A and a pad portion 22B. Therefore, for example, the contact portion 22A for forming an ohmic contact can be used, and the pad portion 22B for coupling wiring can be used, and materials suitable for the respective functions of the contact portion 22A and the pad portion can be selected.

[0079] Furthermore, as described above, in the light emitting element 10 according to the present embodiment, the pad portion 22B is provided on the dielectric layer 19, and is electrically coupled to the contact portion 22A formed on the second conductive type layer 15 via the opening 19H provided on the dielectric layer 19. Therefore, in the case of an LED display (display device 2) described later in which a plurality of light emitting elements 10 are arranged on respective display pixels, it is possible to allow the wiring 51 (e.g., the connection portion 34) for controlling the driving of the light emitting elements 10 arranged on the respective display pixels to be directly coupled to the second electrode 22, rather than crossing the stacked portion of the p-electrode 1022 and the dielectric layer 1019 as in the above-described light emitting element 1000. Therefore, the margin for positional deviation between the wiring 51 and the second electrode 22 can be increased, and the manufacturing yield and reliability can be improved.

[0080] In addition, in the present embodiment, for example, in the case where the first conductive type layer 12 and the contact portion 21A do not absorb light emitted from the active layer 13, as shown in FIG. Figure 1A As shown, the dimension (a1) of the contact portion 22A of the second electrode 22, for example, in the X-axis direction, is set to be equal to or smaller than the dimension (b1) of the contact portion 21A of the first electrode 21, for example, in the X-axis direction. In addition, for example, in the case where one or both of the first conductive type layer 12 and the contact portion 21A absorbs light emitted from the active layer 13, the dimension in the X-axis direction of the contact portion 21A of the first electrode 21 is, for example, set to be equal to or smaller than the dimension in the X-axis direction of the contact portion 22A of the second electrode 22. In addition, the minimum diameter (width in the Z-axis direction) of the pad portion 22B is made smaller than the minimum diameter (for example, similarly, the width in the Z-axis direction) of the pad portion 21B of the first electrode 21. This improves light extraction efficiency and helps support the light emitting element 10.

[0081] Next, the second embodiment and the third embodiment and modified examples will be described. Components corresponding to the light emitting element 10 according to the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

[0082] <2. Second Embodiment>

[0083] Figure 6 (A) schematically shows a cross-sectional configuration of a light emitting element (light emitting element 60) according to a second embodiment of the present disclosure, and Figure 6 (B) schematically shows Figure 6 (A) shows a planar configuration of the light emitting element 60. Note that Figure 6 (A) shows along Figure 6 FIG. 6 is a cross section taken along line IV-IV shown in FIG. 6A and FIG. 6B . As in the first embodiment described above, the light emitting element 60 is suitable for use as a display pixel of an image display device (eg, the display device 2 ) such as a so-called LED display.

[0084] The light emitting element 60 has a semiconductor layer 11 (semiconductor layer) in which a first conductive type layer 12, an active layer 13, and two layers including, for example, a second conductive type layer 14 and a second conductive type layer 15 are sequentially stacked. Figure 6 As shown in (A), the side surface (surface S3) of the light-emitting element 60 has an inclined surface that intersects with the stacking direction (Y-axis direction) of each layer. Specifically, the side surface has an inclined surface so that the cross-section of the light-emitting element 60 has an inverted trapezoidal shape. The light-emitting element 60 has a first electrode 21 on the surface S1 side of the semiconductor layer 11, and a second electrode 62 on the surface S2 side of the semiconductor layer 11. On the side surface and the lower surface of the semiconductor layer 11, a laminated film of a dielectric layer 16, a metal layer 17, and a dielectric layer 18 is stacked in sequence from the side surface (surface S3). The first electrode 21 is electrically coupled to the first conductive type layer 12 through the laminated film. The light-emitting element 60 of this embodiment differs from the light-emitting element of the first embodiment in that the second electrode 62 is provided on the dielectric layer 19 as a continuous layer of a solid film, which is formed together and has no re-formed boundary, and the second electrode 62 is electrically coupled to the second conductive type layer 15 through an opening 19H provided on the dielectric layer 19.

[0085] As described above, in the light emitting element 60 according to the present embodiment, a metal layer having a solid film structure is formed as the second electrode 62 on the dielectric layer 19, which is provided on the second conductive type layer 15 constituting the light extraction surface (surface S2) of the semiconductor layer 11. Therefore, in the present embodiment, the connection portion between the second conductive type layer 15 and the second electrode 62 is flatter than the connection portion of the light emitting element 10 of the first embodiment described above. Therefore, in addition to the effects according to the first embodiment described above, an effect is achieved that the second electrode 62 can be more easily electrically coupled to an external wiring (e.g., wiring 51). In addition, since the formation process is eliminated compared to the light emitting element 10 according to the first embodiment described above, the cost can be reduced.

[0086] <3. Third Embodiment>

[0087] Fig. 7A A cross-sectional configuration of a light emitting element (light emitting element 70 ) according to a third embodiment of the present disclosure is schematically shown, and Figure 7B Schematically showing Fig. 7A The planar configuration of the light emitting element 70 is shown. Note that Fig. 7A Shown along Figure 7B For example, as in the first embodiment described above, the light emitting element 70 is an LED chip and is suitable for use as a display pixel of an image display device (eg, the display device 2) called a so-called LED display.

[0088] The light emitting element 70 has a semiconductor layer 11 (semiconductor layer) in which a first conductive type layer 12, an active layer 13, and two layers including, for example, a second conductive type layer 14 and a second conductive type layer 15 are sequentially stacked. Fig. 7A As shown, the side surface (surface S3) of the light emitting element 70 has an inclined surface that intersects with the stacking direction (Y-axis direction) of each layer. Specifically, the side surface has an inclined surface so that the cross-section of the light emitting element 70 has an inverted trapezoidal shape. The light emitting element 70 has a first electrode 21 on the surface S1 side of the semiconductor layer 11, and has a second electrode 22 on the surface S2 side of the semiconductor layer 11. On the side surface and the lower surface of the semiconductor layer 11, a laminated film of a dielectric layer 16, a metal layer 17, and a dielectric layer 18 is stacked in sequence from the side surface (surface S3) side. The first electrode 21 is electrically coupled to the first conductive type layer 12 through the laminated film. The light emitting element 70 of the present embodiment is different from the light emitting elements of the first and second embodiments in that, for example, a concave-convex structure (for example, a concave portion X) is provided on the outer side of the formation area of ​​the second electrode 22 in the light extraction surface (surface S2) of the semiconductor layer 11. Note that in forming the concave portion as shown in FIG. Fig. 7A In the case of the concavo-convex structure shown, preferably, the second conductive type layer 15 or both the second conductive type layer 14 and the second conductive type layer 15 are processed until the active layer 13 is processed.

[0089] As described above, in the light emitting element 70 according to the present embodiment, a plurality of recesses X are provided in the light extraction surface (surface S2) of the semiconductor layer 11. Therefore, the light extraction efficiency can be greatly improved. In addition, the emitted light extracted from the light extraction surface (surface S2) can be adjusted to have a desired emission angle. Therefore, for example, a Lambertian light distribution can be obtained.

[0090] <4. Modifications>

[0091] Figure 8 is a planar configuration showing a light emitting element (light emitting element 80) according to a modification of the present disclosure. For example, as in the first embodiment described above, the light emitting element 80 is an LED chip and is suitable for use as a display pixel of an image display device (e.g., display device 2) such as a so-called LED display. The light emitting element 80 according to this modification is different from the first, second, and third embodiments in that the long side direction of the first electrode is arranged in the diagonal direction of the light emitting element 80 having a substantially rectangular shape.

[0092] Thus, the first electrode is arranged so that its long side direction is substantially parallel to the diagonal direction of the substantially rectangular light emitting element 80. Therefore, a larger extension can be formed in the long side direction. Therefore, the margin for positional deviation between the wiring 51 and the first electrode can be further increased.

[0093] <5. Application Examples>

[0094] Hereinafter, an application example of any one of the light emitting element 10, the light emitting element 60, the light emitting element 70, and the light emitting element 80 described in the first to third embodiments and the modified examples will be described. Any one of the light emitting element 10, the light emitting element 60, the light emitting element 70, and the light emitting element 80 according to the first to third embodiments can be applied to, for example, an image display device having a light emitting unit (for example, the light emitting unit 1) using a plurality of light emitting elements as display pixels, or a lighting device having a light emitting element used alone or as a light emitting unit.

[0095] An example thereof will be described below.

[0096] (Application Example 1)

[0097] Fig. 9 2 is a perspective view of an example of a schematic configuration of an image display device (display device 2). The display device 2 is a so-called LED display in which LEDs are used as display pixels. For example, Fig. 9 As shown, the display device 2 includes a display panel 210 and a driving circuit (not shown) for driving the display panel 210 .

[0098] The display panel 210 includes a mounting substrate 220 and a transparent substrate 230 stacked on each other. The surface of the transparent substrate 230 serves as an image display surface and has a display area 2A in the middle and a frame area 2B as a non-display area around the middle.

[0099] Fig.10 An example of the layout of the area corresponding to the display area 2A on the surface of the mounting substrate 220 on the transparent substrate 230 side is shown. Fig.10 As shown, for example, in a region corresponding to the display region 2A on the surface of the mounting substrate 220, a plurality of data wirings 221 are formed to extend in a predetermined direction and are arranged in parallel at a predetermined pitch. In a region corresponding to the display region 2A on the surface of the mounting substrate 220, for example, a plurality of scan wirings 222 are further formed to extend in a direction intersecting (for example, perpendicular) the data wirings 221 and are arranged in parallel at a predetermined pitch. The data wirings 221 and the scan wirings 222 include, for example, a conductive material such as Cu.

[0100] The scanning wiring 222 is formed, for example, on the outermost layer, for example, on an insulating layer (not shown) formed on the surface of the substrate. The substrate of the mounting substrate 220 is formed of, for example, a glass substrate, a resin substrate, etc., and the insulating layer on the substrate includes, for example, SiN x 、SiO x or Al x O y . Meanwhile, the data wiring 221 is formed in a layer different from the outermost layer including the scanning wiring 222 (for example, a layer lower than the outermost layer), and is formed, for example, inside the insulating layer on the substrate. On the surface of the insulating layer, in addition to the scanning wiring 222, for example, black is required to be provided when necessary. Black is used to enhance contrast and includes a light absorbing material. For example, black is formed in at least an area where the pad electrode 221B and the pad electrode 222B described later are not formed on the surface of the insulating layer. Note that black can be omitted when necessary.

[0101] Near the intersection of the data wiring 221 and the scanning wiring 222 is a display pixel 223, and a plurality of display pixels 223 are arranged in a matrix form in the display area. A light emitting unit 1 including a plurality of light emitting elements 10 is installed at each display pixel 223. Note that Fig.10 The case where three light emitting elements 10R, 10G, and 10B constitute one display pixel 223 is illustrated, and in this display pixel 223, red light from the light emitting element 10R, green light from the light emitting element 10G, and blue light from the light emitting element 10B can be output.

[0102] The light emitting unit 1 has, for example, a pair of terminal electrodes 31 and 32 for each of the light emitting element 10R, the light emitting element 10G, and the light emitting element 10B. In addition, one terminal electrode 31 is electrically coupled to the data wiring 221, and the other terminal electrode 32 is electrically coupled to the scanning wiring 222. For example, the terminal electrode 31 is electrically coupled to the pad electrode 221B at the end of the branch 221A provided at the data wiring 221. In addition, for example, the terminal electrode 32 is electrically coupled to the pad electrode 222B at the end of the branch 222A provided at the scanning wiring 222.

[0103] like Fig.10 As shown, each of the pad electrode 221B and the pad electrode 222B is formed on the outermost layer, for example, and is provided at a position where each light emitting unit 1 is mounted. Here, the pad electrode 221B and the pad electrode 222B include, for example, a conductive material such as Au (gold).

[0104] The mounting substrate 220 is also provided with a plurality of pillars (not shown) which, for example, adjust the interval between the mounting substrate 220 and the transparent substrate 230. The pillars may be provided in a region facing the display region, or may be provided in a region facing the frame region.

[0105] The transparent substrate 230 is configured by, for example, a glass substrate or a resin substrate. In the transparent substrate 230, the surface on the light emitting unit 1 side may be flat, but is preferably a rough surface. The rough surface may be provided on the entire area facing the display area 2A, or may be provided only in the area facing the display pixel 223. The rough surface has fine unevenness, and light emitted from the light emitting element 10R, the light emitting element 10G, and the light emitting element 10B enters the rough surface. The unevenness of the rough surface may be generated, for example, by sandblasting, dry etching, or the like.

[0106] The driving circuit drives each display pixel 223 (each light emitting unit 1) based on the image signal. The driving circuit includes, for example, a data driver for driving the data wiring 221 coupled to the display pixel 223 and a scan driver for driving the scan wiring 222 coupled to the display pixel 223. The driving circuit may be mounted on the mounting substrate 220, or may be provided independently of the display panel 210 and may be coupled to the mounting substrate 220 via wiring (not shown).

[0107] (Application Example 2)

[0108] Fig.11A and Fig. 11B The planar configuration of the lighting device 200A is shown ( Fig.11A ) and perspective configuration ( Fig. 11B ), the lighting device 200A is an example of a lighting device using the light emitting element 10 (or the light emitting element 60, the light emitting element 70 or the light emitting element 80). Fig.11A and Fig. 11B As shown, the light emitting elements 10 are arranged such that, for example, four light emitting elements 10 are arranged point-symmetrically on a circular mounting table (mounting substrate). Of course, the method of arranging the light emitting elements 10 may be a method other than the point-symmetrical method.

[0109] Fig. 12A and Fig. 12B The planar configuration of the lighting device 200B is shown ( Fig. 12A ) and perspective configuration ( Fig. 12B ), the lighting device 200B is another example of a lighting device using the light emitting element 10. Fig. 12A and Fig. 12B As shown, the light emitting elements 10 are arranged such that, for example, eight light emitting elements 10 are dotted on a ring-shaped mounting table (mounting substrate).

[0110] Fig.13A and Fig. 13B The planar configuration of the lighting device 200C is shown ( Fig.13A ) and perspective configuration ( Fig. 13B), the lighting device 200C is another example of a lighting device using a light emitting element. Fig.13A and Fig. 13B As shown, for example, nine light emitting elements 10 are arranged on a mounting table having a rectangular shape. The lighting device 200C may include a sealed lamp housing.

[0111] Although the present disclosure has been described above with reference to the first to third embodiments and the modified examples, the present disclosure is not limited to the above embodiments, etc., and various modifications may be made. For example, in the first embodiment, etc., although the second conductive type layer is illustrated as a laminated structure including the second conductive type layer 14 and the second conductive type layer 15, the second conductive type layer does not necessarily have a laminated structure, and may have a single-layer structure.

[0112] Note that the present disclosure may also be configured as follows. According to the present technology having the following configuration, a first conductive type layer, an active layer, and a second conductive type layer are stacked in this order. In addition, a first dielectric layer and a second electrode are sequentially arranged on the second surface side of the semiconductor layer, the first surface of the semiconductor layer faces the first conductive type layer side, and the second surface faces the second conductive type layer side. In addition, the second conductive type layer and the second electrode are electrically coupled to each other via an opening arranged on the first dielectric layer. Therefore, for example, the margin for positional deviation between an external wiring arranged on, for example, a light-emitting element and the second electrode can be increased, and the formation area of ​​the second electrode can be reduced. Therefore, the light extraction efficiency can be improved while ensuring connectivity with the conductive electrode. Note that the effects described herein are not necessarily restrictive and may be any effect described in the present disclosure.

[0113] (1) A light emitting element comprising:

[0114] A semiconductor layer having a first surface and a second surface, and including a first conductive type layer, an active layer, and a second conductive type layer stacked in sequence from the first surface side;

[0115] a first dielectric layer disposed on the second surface side of the semiconductor layer and having an opening;

[0116] a first electrode electrically coupled to the first conductive type layer on the first surface side of the semiconductor layer; and

[0117] The second electrode is disposed on the first dielectric layer and is electrically coupled to the second conductive type layer via the opening.

[0118] (2) The light emitting element according to (1) above, wherein the second electrode has a planar shape having a long side direction and a short side direction and having an aspect ratio greater than 1.

[0119] (3) The light emitting element according to (1) or (2) above, wherein the second electrode has a substantially symmetrical structure with the opening interposed therebetween.

[0120] (4) The light-emitting element according to any one of 1 to 3 above, wherein the second electrode comprises:

[0121] a connecting portion covering the opening and electrically coupled to the second conductive type layer; and

[0122] The extending parts extend in directions opposite to each other, and the connecting part is between the extending parts.

[0123] (5) The light emitting element according to (4) above, wherein:

[0124] The connecting portion has a substantially circular shape, and

[0125] The extension portions each extend with a width smaller than a diameter of the connection portion.

[0126] (6) The light-emitting element according to any one of (1) to (5) above, wherein the second electrode comprises:

[0127] a contact portion disposed on the second conductivity type layer and having a perimeter, at least a portion of which is covered by the first dielectric layer; and

[0128] The pad portion is disposed on the first dielectric layer, extends into the interior of the opening and is coupled to the contact portion.

[0129] (7) The light emitting element according to any one of (1) to (6) above, wherein the semiconductor layer has a concavo-convex structure outside a region where the second electrode is formed.

[0130] (8) The light emitting element according to any one of (1) to (7) above, wherein the metal layer is provided from a side surface of the semiconductor layer toward the first surface of the semiconductor layer.

[0131] (9) A light emitting element according to (8) above, wherein:

[0132] The metal layer forms a laminate film together with the second dielectric layer, and

[0133] A metal layer is disposed from a side surface of the semiconductor layer toward the first surface of the semiconductor layer via the second dielectric layer.

[0134] (10) The light emitting element according to any one of (1) to (9) above, wherein an external wiring is coupled to the second electrode.

[0135] (11) A light emitting element according to (10) above, wherein:

[0136] The second electrode has a planar shape having a long side direction and a short side direction, and

[0137] The external wiring is arranged to intersect with the long side direction of the second electrode.

[0138] (12) The light-emitting element according to any one of (6) to (11) above, wherein the first electrode comprises:

[0139] a contact portion disposed on the first conductive type layer and having a perimeter, at least a portion of which is covered by a second dielectric layer, the second dielectric layer being disposed from a side surface of the semiconductor layer toward a first surface of the semiconductor layer; and

[0140] a pad portion extending to the inside of the opening provided on the second dielectric layer and coupled to the contact portion, and

[0141] Wherein, when the contact portion between the first conductive type layer and the first electrode does not absorb light emitted from the active layer, the size of the contact portion of the second electrode in the uniaxial direction is equal to or smaller than the size of the contact portion of the first electrode in the uniaxial direction.

[0142] (13) The light-emitting element according to any one of (6) to (11) above, wherein the first electrode comprises:

[0143] a contact portion disposed on the first conductive type layer and having a perimeter, at least a portion of which is covered by a second dielectric layer, the second dielectric layer being disposed from a side surface of the semiconductor layer toward a first surface of the semiconductor layer; and

[0144] a pad portion extending to the inside of the opening provided on the second dielectric layer and coupled to the contact portion, and

[0145] In which, when one or both of the first conductive type layer and the contact portion of the first electrode absorbs light emitted from the active layer, the size of the contact portion of the second electrode in the uniaxial direction is equal to or greater than the size of the contact portion of the first electrode in the uniaxial direction.

[0146] (14) The light-emitting element according to any one of (6) to (13) above, wherein the first electrode comprises:

[0147] a contact portion disposed on the first conductive type layer and having a periphery, at least a portion of the periphery being covered by a second dielectric layer disposed from a side surface of the semiconductor layer toward a first surface of the semiconductor layer; and

[0148] a pad portion extending to the inside of the opening provided on the second dielectric layer and coupled to the contact portion, and

[0149] The minimum diameter of the pad portion of the second electrode is smaller than the minimum diameter of the pad portion of the first electrode.

[0150] (15) The light emitting element according to any one of (1) to (14) above, wherein the first electrode is electrically coupled to a structure having a wiring electrode.

[0151] (16) The light emitting element according to any one of (1) to (15) above, wherein the first conductivity type layer includes an n-type semiconductor layer, and the second conductivity type layer includes a p-type semiconductor layer, and

[0152] The first electrode includes an n-electrode, and the second electrode includes a p-electrode.

[0153] (17) An image display device having a plurality of light-emitting elements, the plurality of light-emitting elements comprising:

[0154] A semiconductor layer having a first surface and a second surface, and including a first conductive type layer, an active layer, and a second conductive type layer stacked in sequence from the first surface side;

[0155] a first dielectric layer disposed on the second surface side of the semiconductor layer and having an opening;

[0156] a first electrode electrically coupled to the first conductive type layer on the first surface side of the semiconductor layer; and

[0157] The second electrode is disposed on the first dielectric layer and is electrically coupled to the second conductive type layer via the opening.

[0158] This application claims the benefit of Japanese Priority Patent Application JP 2018-197374 filed in the Japan Patent Office on October 19, 2018, the entire contents of which are incorporated herein by reference.

[0159] It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may occur depending on design requirements and other factors as long as they are within the scope of the appended claims or the equivalents thereof.

Claims

1. A light emitting element, comprising: A semiconductor layer having a first surface and a second surface, and including a first conductive type layer, an active layer, and a second conductive type layer stacked in sequence from the first surface side; a first dielectric layer disposed on the second surface side of the semiconductor layer and having an opening; a first electrode electrically coupled to the first conductive type layer on the first surface side of the semiconductor layer; as well as a second electrode disposed on the first dielectric layer and electrically coupled to the second conductive type layer via the opening, Wherein, the second electrode comprises: a second contact portion disposed on the second conductive type layer and having a perimeter, at least a portion of which is covered by the first dielectric layer; and a second pad portion, which is disposed on the first dielectric layer, extends to the inside of the opening and is coupled to the second contact portion, wherein a wiring for controlling the driving of the light emitting element is directly coupled to the second pad portion of the second electrode, Wherein, the first electrode comprises: a first contact portion, disposed on the first conductive type layer and having a periphery, at least a portion of the periphery being covered by a second dielectric layer, the second dielectric layer being disposed from a side surface of the semiconductor layer toward the first surface of the semiconductor layer; and a first pad portion extending into the interior of the opening disposed on the second dielectric layer and coupled to the first contact portion, and Wherein, when the first conductive type layer and the first contact portion of the first electrode do not absorb light emitted from the active layer, the size of the second contact portion of the second electrode in a uniaxial direction is equal to or smaller than the size of the first contact portion of the first electrode in a uniaxial direction, wherein the second pad portion of the second electrode has a planar shape having a long side direction and a short side direction, wherein the uniaxial direction is the long side direction, and wherein the wiring is arranged to intersect with the long side direction of the second pad portion.

2. The light-emitting element according to claim 1, wherein The planar shape has an aspect ratio greater than 1.

3. The light-emitting element according to claim 1, wherein The second electrode has a symmetrical structure, and the opening of the first dielectric layer is between the symmetrical structures.

4. The light-emitting element according to claim 1, wherein The second pad portion includes: a connecting portion covering the opening of the first dielectric layer and electrically coupled to the second conductive type layer; and The extension parts extend on two opposite sides of the connecting part.

5. The light emitting element according to claim 4, wherein The connecting portion is circular, and The extending portions at both sides of the connecting portion each extend with a width smaller than a diameter of the connecting portion.

6. The light-emitting element according to claim 1, wherein The semiconductor layer has a concavo-convex structure, and the concavo-convex structure is located outside a region where the second electrode is formed.

7. The light-emitting element according to claim 1, wherein A metal layer is provided from a side surface of the semiconductor layer toward the first surface of the semiconductor layer.

8. The light-emitting element according to claim 7, wherein The metal layer forms a laminate film together with the second dielectric layer, and The metal layer is provided from the side surface of the semiconductor layer toward the first surface of the semiconductor layer via the second dielectric layer.

9. The light-emitting element according to claim 1, wherein When at least one of the first conductive type layer and the first contact portion of the first electrode absorbs light emitted from the active layer, a size of the second contact portion of the second electrode in a uniaxial direction is equal to or greater than a size of the first contact portion of the first electrode in a uniaxial direction.

10. The light emitting element according to claim 1, wherein A minimum diameter of the second pad portion of the second electrode is smaller than a minimum diameter of the first pad portion of the first electrode.

11. The light emitting element according to claim 1, wherein The first electrode is electrically coupled to a structure having a terminal electrode.

12. The light emitting element according to claim 1, wherein The first conductive type layer includes an n-type semiconductor layer, and the second conductive type layer includes a p-type semiconductor layer, and The first electrode includes an n-electrode, and the second electrode includes a p-electrode.

13. An image display device having a plurality of light-emitting elements, each of the plurality of light-emitting elements comprising: A semiconductor layer having a first surface and a second surface, and including a first conductive type layer, an active layer, and a second conductive type layer stacked in sequence from the first surface side; a first dielectric layer disposed on the second surface side of the semiconductor layer and having an opening; a first electrode electrically coupled to the first conductive type layer on the first surface side of the semiconductor layer; as well as a second electrode disposed on the first dielectric layer and electrically coupled to the second conductive type layer via the opening, Wherein, the second electrode comprises: a second contact portion disposed on the second conductive type layer and having a perimeter, at least a portion of which is covered by the first dielectric layer; and a second pad portion, which is disposed on the first dielectric layer, extends to the inside of the opening and is coupled to the second contact portion, wherein a wiring for controlling the driving of the light emitting element is directly coupled to the second pad portion of the second electrode, Wherein, the first electrode comprises: a first contact portion, disposed on the first conductive type layer and having a periphery, at least a portion of the periphery being covered by a second dielectric layer, the second dielectric layer being disposed from a side surface of the semiconductor layer toward the first surface of the semiconductor layer; and a first pad portion extending into the interior of the opening disposed on the second dielectric layer and coupled to the first contact portion, and Wherein, when the first conductive type layer and the first contact portion of the first electrode do not absorb light emitted from the active layer, the size of the second contact portion of the second electrode in a uniaxial direction is equal to or smaller than the size of the first contact portion of the first electrode in a uniaxial direction, wherein the second pad portion of the second electrode has a planar shape having a long side direction and a short side direction, wherein the uniaxial direction is the long side direction, and wherein the wiring is arranged to intersect with the long side direction of the second pad portion.

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