Light emitting diode and light emitting device

Abstract

The application provides a light emitting diode and a light emitting device. The light emitting diode comprises a semiconductor stack, at least one conductive hole arranged in the semiconductor stack, and an insulating layer and a first bonding layer arranged on the inner side wall of the conductive hole in sequence, and the semiconductor stack is bonded to a substrate through the first bonding layer and a second bonding layer. Corresponding to the lower area of the conductive hole, the first bonding layer has a hole, and a repair layer is arranged in the hole. The porosity in the first bonding layer is effectively improved, the reliability of the light emitting diode is improved, the thermal conductivity of the repair layer is greater than that of the first bonding layer, the efficiency of heat conduction from the first bonding layer to the surrounding environment is improved, the risk of local hot spots is effectively reduced, the performance of the light emitting diode is improved, the hardness of the repair layer is greater than that of the first bonding layer, the mechanical strength of the first bonding layer is improved, and the durability and reliability of the light emitting diode are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor devices, in particular to a light emitting diode and a light emitting device. BACKGROUND

[0002] A light emitting diode (LED) is a semiconductor optoelectronic device that directly converts electrical energy into light energy when current passes through it, and works on the principle of electroluminescence. LEDs are widely used in general lighting, backlight display, traffic signal lights, automotive lighting, medical equipment, plant growth lamps, etc.

[0003] One of the design forms of LEDs is vertical structure chips, which make the direction of electrical connection and / or light emission perpendicular to the substrate surface. This structure allows more efficient heat management, current path and light output, and is suitable for high-power and high-brightness applications.

[0004] Vertical structure chips usually contain P-type and N-type layers, which form a mesa structure through specific process steps to achieve vertical conduction path of the device. However, due to inherent differences in material growth, etching process and subsequent metallization steps, there is often a significant height difference between the N-type mesa (especially the area containing the metallized via) and the P-type mesa. This height difference becomes a key factor affecting the quality of bonding during the subsequent silicon (Si) substrate or other material bonding process.

[0005] The bonding process in the prior art often has difficulty in ensuring the uniformity and continuity of the metal layer on the entire interface when dealing with this height difference. The height difference between the metal at the N-type hole and the P-type mesa will cause holes to form during the bonding process. These holes not only destroy the integrity of the metal layer, but also become a hidden danger for heat management during the subsequent operation of the device.

[0006] During the long-term operation of the device, especially during the high-temperature and high-current density aging test, the air in these holes will accumulate heat due to the thermal resistance effect of the metal layer. With the continuous accumulation of heat, the temperature of the metal layer around the hole rises sharply, eventually leading to peeling or electrical leakage of the metal layer, seriously affecting the performance and reliability of the device.

[0007] In order to improve the performance and reliability of the device, the present application provides a light emitting diode and a light emitting device. SUMMARY

[0008] In view of the defects and deficiencies of the prior art, the present application provides a light emitting diode and a light emitting device. The light emitting diode is provided with a repair layer in the hole, which effectively improves the porosity in the first bonding layer and improves the reliability of the light emitting diode. The thermal conductivity of the repair layer is greater than that of the first bonding layer, which improves the efficiency of heat conduction from the first bonding layer to the surrounding environment, reduces the risk of local hot spots, and improves the performance of the light emitting diode. The hardness of the repair layer is greater than that of the first bonding layer, which effectively improves the mechanical strength of the first bonding layer and improves the durability and reliability of the light emitting diode.

[0009] An embodiment of the present application provides a light emitting diode, comprising:

[0010] A semiconductor stack comprising, from top to bottom, a first semiconductor layer, an active layer, and a second semiconductor layer stacked in sequence;

[0011] At least one conductive hole is provided in the semiconductor stack, the conductive hole penetrates the second semiconductor layer, the active layer, and at least part of the first semiconductor layer, and the inner side wall of the conductive hole is provided with an insulating layer and a first bonding layer in sequence, and the first bonding layer is electrically connected with the first semiconductor layer through the conductive hole;

[0012] A substrate is bonded with the first bonding layer through a second bonding layer;

[0013] Corresponding to the lower region of the conductive hole, the first bonding layer has a hole, and a repair layer is provided in the hole, the thermal conductivity of the repair layer is greater than that of the first bonding layer, and the hardness of the repair layer is greater than that of the first bonding layer.

[0014] According to another embodiment of the present application, a light emitting device is provided, comprising a circuit board and a plurality of light emitting elements provided on the circuit board, the light emitting elements comprising the light emitting diode described above or comprising the light emitting diode prepared by the preparation method described above.

[0015] As described above, the light emitting diode and the light emitting device of the present application have the following beneficial effects:

[0016] The light emitting diode of the present application repairs the defects of the first bonding layer by providing a repair layer in the hole of the first bonding layer, reduces the porosity in the first bonding layer, improves the reliability of the light emitting diode, and sets the thermal conductivity of the repair layer to be greater than that of the first bonding layer, which improves the efficiency of heat conduction from the first bonding layer to the surrounding environment, reduces the risk of local hot spots, and improves the performance of the light emitting diode. The hardness of the repair layer is greater than that of the first bonding layer, which effectively improves the mechanical strength of the first bonding layer and improves the durability and reliability of the light emitting diode. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 A top view of a light emitting diode is shown.

[0018] Figure 2 A cross-sectional view of the light emitting diode is shown. Figure 1 A cross-sectional view of the light emitting diode is shown.

[0019] Figure 3 A cross-sectional view of the light emitting diode is shown.

[0020] Figures 4 to 10 A cross-sectional view of the light emitting diode is shown.

[0021] Figure 11 A cross-sectional view of the light emitting diode is shown.

[0022] Element Number Description

[0023] 10, circuit board; 20, light emitting element; 100, semiconductor stack; 101, conductive hole; 110, first semiconductor layer; 120, active layer; 130, second semiconductor layer; 200, insulating layer; 201, transparent conductive layer; 202, metal reflective layer; 203, metal protective layer; 210, first insulating layer; 211, through hole; 220, second insulating layer; 300, first bonding layer; 301, hole; 302, repair layer; 400, second bonding layer; 500, substrate; 510, first region; 520, second region; 600, metal layer; 700, electrode; 800, passivation layer; 900, substrate. DETAILED DESCRIPTION

[0024] The present application is herein described, by way of example only, with reference to certain embodiments thereof. It is to be understood that there is no intention to limit the application to the specific embodiments, but on the contrary, the intent is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the application as defined by the appended claims.

[0025] The present application provides a light emitting diode, comprising:

[0026] a semiconductor stack comprising, from top to bottom, a first semiconductor layer, an active layer, and a second semiconductor layer stacked in sequence;

[0027] The conductive hole is arranged in the semiconductor stack, and the conductive hole penetrates the second semiconductor layer, the active layer and at least part of the first semiconductor layer, and the inner side wall of the conductive hole is sequentially provided with an insulating layer and a first bonding layer, and the first bonding layer is electrically connected with the first semiconductor layer through the conductive hole;

[0028] The substrate is bonded with the first bonding layer through a second bonding layer.

[0029] The first bonding layer has a hole corresponding to the lower area of the conductive hole, and the hole is provided with a repair layer, the thermal conductivity of the repair layer is greater than that of the first bonding layer, and the hardness of the repair layer is greater than that of the first bonding layer.

[0030] The light emitting diode provided by the embodiment effectively improves the porosity of the first bonding layer by arranging the repair layer in the hole, avoids the accumulation of air in the hole in the first bonding layer, improves the reliability of the light emitting diode, and improves the performance of the light emitting diode by improving the efficiency of heat conduction from the first bonding layer to the surrounding environment and reducing the risk of local hot spots.

[0031] In some embodiments, the repair layer has insulation.

[0032] The repair layer in the light emitting diode of the embodiment has insulation, so that the light emitting diode current does not directly penetrate from the conductive hole when conducting heat, and the current diffusion can be effectively realized, and the heat accumulation is further reduced.

[0033] In some embodiments, the hole is a regularly shaped or irregularly shaped hole naturally formed after the first bonding layer fills the conductive hole.

[0034] When the first bonding layer fills the conductive hole, the height difference between the conductive hole and the second semiconductor layer causes the first bonding layer to have a height difference. When bonded with the second bonding layer, the first bonding layer in the area below the conductive hole will have a hole. Since the hole is naturally formed, its shape may be regular or irregular. After the first bonding layer and the second bonding layer are bonded, the hole will be filled with air. Since the air will accumulate heat in the first bonding layer, the heat cannot be transferred out, which may cause the first bonding layer to peel off or cause the first bonding layer to melt and leak.

[0035] In some embodiments, the surface of the repair layer close to the second bonding layer is flush with the surface of the first bonding layer close to the second bonding layer.

[0036] The light emitting diode of the embodiment can improve the problem of uneven surface of the first bonding layer and reduce the void rate in the first bonding layer by setting the surface of the repair layer and the surface of the first bonding layer to be flush.

[0037] In some embodiments, the absolute value of the height difference between the surface of the repair layer close to the surface of the second bonding layer and the surface of the first bonding layer close to the surface of the second bonding layer is less than 0.1 μm. Due to the difference in material between the repair layer and the first bonding layer, the height difference between the two may be certain, but the absolute value of the height difference should be less than 0.1 μm to improve the problem of uneven surface of the first bonding layer.

[0038] In some embodiments, the diameter of the conductive hole gradually increases from the first semiconductor layer to the second semiconductor layer, and the vertical projection area of the first bonding layer on the second bonding layer is greater than the vertical projection area of the repair layer on the second bonding layer in the area below the maximum diameter of the conductive hole.

[0039] In the light emitting diode of the embodiment, the size of the first bonding layer and the repair layer is limited corresponding to the conductive hole to ensure current conduction and improve the performance of the light emitting diode.

[0040] In some embodiments, the width of the repair layer and twice the width of the first bonding layer are equal to the maximum diameter of the conductive hole in the area below the maximum diameter of the conductive hole.

[0041] In some embodiments, the distance between the centers of two adjacent conductive holes is less than or equal to 200 μm. By limiting the distance between the centers of two adjacent conductive holes, the current distribution is uniform, the light emitting efficiency and brightness of the light emitting diode are improved, the heat is dissipated to the outside from the light emitting area, the working temperature of the light emitting diode is reduced, the reliability of the light emitting diode is improved, and the service life of the light emitting diode is prolonged.

[0042] In some embodiments, the distance between the edges of two adjacent repair layers is less than or equal to 180 μm. By limiting the distance between the edges of two adjacent repair layers, heat can be more effectively transferred to the outside through the repair layer, which helps to improve the heat conduction efficiency of the light emitting diode and reduce the local temperature. At the same time, the repair layer has high hardness, which can provide additional mechanical support for the light emitting diode and enhance the overall stability and durability of the light emitting diode.

[0043] In some embodiments, the thermal conductivity of the repair layer is between 500 W / m·K and 2200 W / m·K, and the Vickers hardness is between 20 GPa and 200 Gpa.

[0044] The thermal conductivity of the repair layer of the light emitting diode is greater than that of the first bonding layer, the thermal conductivity of the substrate can be increased, and heat can be transferred to the surrounding environment; the hardness of the repair layer is greater than that of the first bonding layer, the mechanical strength of the first bonding layer can be improved, and the reliability of the light emitting diode can be improved.

[0045] In some embodiments, the material of the repair layer is diamond or diamond-like.

[0046] The material of the repair layer of the light emitting diode is diamond or diamond-like, the specific heat of diamond or diamond-like is small, which will not cause heat accumulation, and can withstand thermal shock of sudden cooling and heat accumulation, and is a good heat sink material.

[0047] In some embodiments, the inner side wall of the conductive hole is further provided with a metal layer, the metal layer is arranged between the insulating layer and the first bonding layer, and the metal layer is electrically connected with the first semiconductor layer through the conductive hole.

[0048] In some embodiments, the surface of the substrate close to the second bonding layer includes a first region and a second region, and the second region surrounds the first region.

[0049] Corresponding to the first region, the semiconductor stack is arranged above the substrate;

[0050] From top to bottom, the semiconductor stack and the substrate are sequentially stacked with the insulating layer, the first bonding layer and the second bonding layer; the second bonding layer, the first bonding layer and the insulating layer all cover from the first region to the second region.

[0051] In some embodiments, the surface of the second semiconductor layer away from the active layer is provided with a transparent conductive layer, and the transparent conductive layer is arranged between the second semiconductor layer and the insulating layer.

[0052] From top to bottom, the insulating layer includes a first insulating layer and a second insulating layer; corresponding to the region covered by the second semiconductor layer, the first insulating layer is provided with a through hole, a metal reflection layer is arranged between the first insulating layer and the second insulating layer, the metal reflection layer covers the first insulating layer and fills the through hole to be electrically connected with the transparent conductive layer; a metal protection layer is arranged between the metal reflection layer and the second insulating layer, the metal protection layer covers from the first region to the second region, and the second insulating layer wraps the side wall of the metal protection layer.

[0053] In some embodiments, corresponding to the second region, the first insulating layer has an interrupted region, the interrupted region is provided with an electrode, and the electrode is electrically connected with the metal protection layer.

[0054] Another embodiment of the present application provides a light emitting device, comprising a circuit board and a plurality of light emitting elements disposed on the circuit board, the light emitting elements comprising the light emitting diode described above or comprising the light emitting diode prepared by the preparation method described above.

[0055] The light emitting elements in the light emitting device of the present embodiment adopt the light emitting diode provided by the present application or the light emitting diode prepared by the preparation method provided by the present application. Since the light emitting diode provided by the present application repairs the defects of the first bonding layer by disposing a repair layer in the hole of the first bonding layer, the void rate of the first bonding layer can be reduced, the reliability of the light emitting diode can be improved, and the reliability of the light emitting device can be improved. The thermal conductivity of the repair layer is greater than that of the first bonding layer, which improves the efficiency of the first bonding layer in conducting to the surrounding environment, reduces the risk of local hot spots, improves the performance of the light emitting diode, and further improves the performance of the light emitting device. The hardness of the repair layer is greater than that of the first bonding layer, which effectively improves the mechanical strength of the first bonding layer, improves the durability and reliability of the light emitting diode, and further improves the durability and reliability of the light emitting device.

[0056] The light emitting diode in the prior art, one design form is vertical structure chip, as shown in Figure 1 and Figure 2 , usually comprises a first semiconductor layer 110 and a second semiconductor layer 130, which form a mesa structure through specific process steps to realize the vertical conduction path of the light emitting diode. However, due to the inherent differences in material growth, etching process and subsequent metallization steps, after the first bonding layer 300 is filled into the conductive hole 101 and formed below the second semiconductor layer 130, there is a height difference between the first bonding layer 300 at the conductive hole 101 and the first bonding layer 300 below the second semiconductor layer 130. In the process of bonding the first bonding layer 300 to the substrate 500 through the second bonding layer 400, due to the height difference of the first bonding layer 300, the first bonding layer 300 corresponding to the conductive hole 101 region will form holes 301 in the bonding process. These holes 301 not only damage the integrity of the first bonding layer 300, but also become a hidden danger for heat management in the subsequent operation of the light emitting diode. It can be understood that, Figure 2 The shape of the hole 301 in the above is only an example, and the shape of the hole 301 is likely to be irregular, unlike the example shown in the figure. In the long-term working process of the light emitting diode, especially during the aging test of high temperature and high current density, the air in these holes 301 will accumulate heat due to the thermal resistance effect of the metal of the first bonding layer 300. With the continuous accumulation of heat, the temperature of the metal around the hole 301 rises sharply, eventually leading to the peeling of the first bonding layer 300 or the leakage due to the melting of the first bonding layer 300, which not only seriously affects the reliability of the light emitting diode, but also can cause the failure of the light emitting diode.

[0057] To address the above-mentioned deficiencies, this application provides a light-emitting diode and a light-emitting device. The following embodiments will provide a detailed description.

[0058] Example 1

[0059] This embodiment provides a light-emitting diode, such as Figure 3 As shown, the light-emitting diode includes a substrate 500 and a semiconductor stack 100 disposed above the substrate 500. The semiconductor stack 100 includes a first semiconductor layer 110, an active layer 120, and a second semiconductor layer 130 stacked sequentially from top to bottom. At least one conductive via 101 is disposed within the semiconductor stack 100, penetrating the second semiconductor layer 130, the active layer 120, and at least a portion of the first semiconductor layer 110. An insulating layer 200 and a first bonding layer 300 are sequentially disposed from the outside to the inside of the inner sidewall of the conductive via 101. The first bonding layer 300 passes through the conductive via 101 and is electrically connected to the first semiconductor layer 110. The insulating layer 200 is disposed below the second semiconductor layer 130, and the first bonding layer 300 is disposed below the insulating layer 200. The substrate 500 is bonded to the first bonding layer 300 via a second bonding layer 400. In the region below the conductive via 101, the first bonding layer 300 has a cavity 301, and a repair layer 302 is disposed within the cavity 301. By filling the cavity 301 with the repair layer 302, the void ratio within the first bonding layer 300 can be effectively improved, thereby enhancing the reliability of the light-emitting diode (LED). The thermal conductivity of the repair layer 302 is greater than that of the first bonding layer 300, which improves the efficiency of heat conduction from the first bonding layer 300 to the surrounding environment, effectively reducing the risk of localized hot spots and improving the performance of the LED. The hardness of the repair layer 302 is greater than that of the first bonding layer 300, which improves the mechanical strength of the first bonding layer 300, thereby enhancing the durability and reliability of the LED.

[0060] The hole 301 is a regular or irregular shape formed naturally by the height difference of the first bonding layer 300 after the conductive hole 101 is filled by the first bonding layer 300. The height difference of the first bonding layer 300 is formed by the height difference between the second semiconductor layer 130 and the conductive hole 101, and the hole 301 is formed in the first bonding layer 300 in the region below the conductive hole 101.

[0061] The first semiconductor layer 110 is an N-type semiconductor layer that provides electrons by N-type doping, and the N-type semiconductor layer can be formed by doping a semiconductor with, for example, Si, Ge, Sn, Se, Te, or the like. The second semiconductor layer 130 is a P-type semiconductor layer that provides holes by P-type doping, and the P-type semiconductor layer can be formed by doping a semiconductor with, for example, Mg, Zn, Ca, Sr, Ba, or the like. The active layer 120 can be a single quantum well structure or a multiple quantum well (MQWs) structure formed by alternately stacking quantum well layers and quantum barrier layers, and the quantum barrier layers can be GaN layers, AlGaN layers, or AlGaInP. Alternatively, the active layer 120 can include a GaN / AlGaN, InAlGaN / InAlGaN, InGaN / AlGaN, GaInP / AlGaInP, GaInP / AlInP, or InGaAs / AlInGaAs multiple quantum well structure. In order to improve the light emission efficiency of the active layer 120, the depth of the quantum well, the number of layers, the thickness, and / or other characteristics of the pairs of quantum well and quantum well barrier in the active layer 120 can be changed.

[0062] The substrate 500 provides mechanical support for the light emitting diode, and the substrate 500 can be a conductive substrate. The material of the conductive substrate can be, for example, silicon, silicon carbide, or a metal.

[0063] The material of the insulating layer 200 can be, for example, one of SiO2, SiN, SiO x N y , TiO2, Si3N4, Al2O3, TiN, AlN, ZrO2, TiAlN, TiSiN, HfO2, TaO2, or MgF2, or a Bragg reflector (DBR) formed by repeatedly stacking two or more of the aforementioned materials.

[0064] The first bonding layer 300 and the second bonding layer 400 adhere the semiconductor stack 100 to the substrate 500 on one side, and the first bonding layer 300 and the second bonding layer 400 are typically made of a metal such as gold, tin, titanium, nickel, platinum, or the like, and the first bonding layer 300 and the second bonding layer 400 can also be a combination of multiple layers of materials.

[0065] In an optional embodiment, the repair layer 302 is insulating, so that the repair layer 302 can block the current from directly penetrating downward from the conductive hole 101, reduce the current density in the area below the conductive hole 101 and its surroundings, alleviate the current crowding effect near the conductive hole 101, make the current more diffuse to other areas below the conductive hole 101, reduce the heat generation of the light emitting diode, and improve the reliability, thermal stability, and lifespan of the light emitting diode.

[0066] In an optional embodiment, the surface of the repair layer 302 close to the second bonding layer 400 is flush with the surface of the first bonding layer 300 close to the second bonding layer 400, that is, the lower surface of the repair layer 302 is flush with the lower surface of the first bonding layer 300, which can improve the flatness of the surface of the first bonding layer 300 bonded to the second bonding layer 400, reduce the void rate in the first bonding layer 300, and improve the reliability of the light emitting diode.

[0067] In an optional embodiment, the absolute value of the height difference between the surface of the repair layer 302 close to the second bonding layer 400 and the surface of the first bonding layer 300 close to the second bonding layer 400 is less than 0.1 μm. The height difference between the lower surface of the repair layer 302 and the lower surface of the first bonding layer 300 is between -0.1 μm and 0.1 μm. Since the material of the repair layer 302 is different from the material of the first bonding layer 300, the height difference between them may be certain, but the height difference should be within the above range to improve the problem of uneven height of the lower surface of the first bonding layer 300. Further, the height difference between the lower surface of the repair layer 302 and the lower surface of the first bonding layer 300 is between -0.05 μm and 0.05 μm, which further improves the problem of uneven height of the lower surface of the first bonding layer 300.

[0068] In an optional embodiment, the aperture of the conductive hole 101 gradually increases from the first semiconductor layer 110 to the second semiconductor layer 130, that is, the aperture of the conductive hole 101 gradually increases from top to bottom, the minimum aperture of the conductive hole 101 is R1, and the maximum aperture of the conductive hole 101 is R2. The positions of R1 and R2 marked in the figure are only for illustration to explain the change of the aperture of the conductive hole 101. Corresponding to the area below the maximum aperture R2 of the conductive hole 101, the vertical projection area of the first bonding layer 300 on the second bonding layer 400 is greater than the vertical projection area of the repair layer 302 on the second bonding layer 400, as shown in FIG. 3B, that is, corresponding to the area below the conductive hole 101, the width of the first bonding layer 300 below the conductive hole 101 is greater than the width of the repair layer 302. In this way, when the repair layer 302 has insulation, the current can be conducted from the conductive hole 101 to the first bonding layer 300 and to the second bonding layer 400, that is, the conductivity of the first bonding layer 300 is ensured, and the current is conducted in the direction of the substrate 500, and the current crowding effect near the conductive hole 101 is also alleviated. Figure 3 In an optional embodiment, as shown in FIG. 3B, corresponding to the area below the maximum aperture R2 of the conductive hole 101, the width T1 of the repair layer 302 and twice the width T2 of the first bonding layer 300 are equal to the maximum aperture R2 of the conductive hole 101. More specifically, in the area below the conductive hole 101 and where the repair layer 302 is located, R2 = T1 + 2T2. Figure 3

[0069] In an optional embodiment, as shown in FIG. 3B, corresponding to the area below the maximum aperture R2 of the conductive hole 101, the width T1 of the repair layer 302 and twice the width T2 of the first bonding layer 300 are equal to the maximum aperture R2 of the conductive hole 101. More specifically, in the area below the conductive hole 101 and where the repair layer 302 is located, R2 = T1 + 2T2.​

[0070] In an optional embodiment, the distance L1 between the centers of two adjacent conductive holes 101 is less than or equal to 200 μm. Since the walls of the conductive holes 101 can have a certain degree of inclination, but the conductive holes 101 have a central axis and the centers are located on the central axis, the distance L1 between the centers of two adjacent conductive holes 101 is limited to improve the uniformity of current distribution, thereby improving the light-emitting efficiency and brightness of the light-emitting diode; at the same time, it is helpful to dissipate heat from the light-emitting region to the outside, thereby reducing the operating temperature of the light-emitting diode and improving the reliability and life of the light-emitting diode.

[0071] In an optional embodiment, the distance L2 between the edges of two adjacent repair layers 302 is less than or equal to 180 μm. Since the thermal conductivity of the repair layer 302 is greater than that of the first bonding layer 300, by limiting the distance between the edges of two adjacent repair layers 302, heat can be transferred to the outside more quickly through the repair layer 302, which helps to reduce the local temperature and improve the heat conduction efficiency of the light-emitting diode; at the same time, since the repair layer 302 has high hardness, the adjacent repair layers together provide additional mechanical support for the light-emitting diode, enhancing the overall stability and durability of the light-emitting diode.

[0072] In an optional embodiment, the thermal conductivity of the repair layer 302 is between 500 W / m·K and 2200 W / m·K, and the Vickers hardness is between 20 GPa and 200 Gpa. Specifically, the thermal conductivity of the repair layer 302 can be, for example, 500 W / m·K, 800 W / m·K, 1000 W / m·K, 1300 W / m·K, 1600 W / m·K, 1900 W / m·K, 2200 W / m·K, etc. The thermal conductivity of the repair layer 302 is greater than that of the first bonding layer 300, which can increase the thermal conductivity of the substrate 500. The hardness of the repair layer 302 can be, for example, 20 GPa, 50 GPa, 100 GPa, 150 GPa, 200 GPa, etc. The hardness of the repair layer 302 is greater than that of the first bonding layer 300, which can improve the mechanical strength of the first bonding layer 300 and improve the reliability of the light-emitting diode.

[0073] In an optional embodiment, the material of the repair layer 302 is diamond or diamond-like. The repair layer 302 uses diamond or diamond-like as raw material, which can improve the unevenness of the surface of the first bonding layer 300 and the second bonding layer 400, and reduce the void rate in the first bonding layer 300. The thermal conductivity of diamond or diamond-like is greater than that of the first bonding layer 300, which can increase the thermal conductivity of the first bonding layer 300, and facilitate the first bonding layer 300 to transfer heat to the surrounding environment. The specific heat of diamond or diamond-like is small, and it cannot accumulate heat energy, and it can withstand thermal shock when it is suddenly cooled or heated. It is a good heat sink material. The thermal expansion coefficient of diamond or diamond-like is close to that of silicon. When the substrate 500 is made of silicon material, the repair layer 302 uses diamond or diamond-like, which can further adapt to the stress of the substrate 500. Diamond or diamond-like has insulation, and when the repair layer 302 uses diamond or diamond-like, the current will not directly pass through the conductive hole 101 when conducting, which can achieve the purpose of current diffusion, further reduce heat accumulation, and improve the performance and reliability of the light-emitting diode.

[0074] In an optional embodiment, as shown in Figure 3 , the inner side wall of the conductive hole 101 is further provided with a metal layer 600 between the insulating layer 200 and the first bonding layer 300. The metal layer 600 is electrically connected with the first semiconductor layer 110 through the conductive hole 101. The metal layer 600 can be an N-type metal layer, and its material can be Al, Ag, Cr, Pt, TiW, for example.

[0075] In an optional embodiment, as shown in Figure 1 and Figure 3As shown, the surface of the substrate 500 close to the second bonding layer 400 (i.e. the upper surface of the substrate 500) comprises a first region 510 and a second region 520 surrounding the first region 510. It can be understood that the first region 510 and the second region 520 are both three-dimensional regions, which can extend in a direction perpendicular to the upper surface of the substrate 500. Corresponding to the first region 510, the semiconductor stack 100 is arranged above the substrate 500. From top to bottom, the semiconductor stack 100 and the substrate 500 are sequentially stacked with the insulating layer 200, the first bonding layer 300 and the second bonding layer 400, and the insulating layer 200, the first bonding layer 300 and the second bonding layer 400 all extend from the first region 510 to the second region 520. The inner side wall of the conductive hole 101 is sequentially provided with the insulating layer 200, the metal layer 600 and the first bonding layer 300 from outside to inside, and the metal layer 600 is also arranged at the contact position of the conductive hole 101 and the first semiconductor layer 110, so as to realize the electrical connection between the metal layer 600 and the first semiconductor layer 110. After the insulating layer 200 and the metal layer 600 are arranged on the side wall of the conductive hole 101 and the metal layer 600 is arranged at the contact position of the conductive hole 101 and the first semiconductor layer 110, the first bonding layer 300 is filled in the remaining space of the conductive hole 101, and the first bonding layer 300 is electrically connected to the first semiconductor layer 110 through the metal layer 600.

[0076] In an optional embodiment, as shown in Figure 3 As shown, the surface of the substrate 500 close to the second bonding layer 400 (i.e. the upper surface of the substrate 500) comprises a first region 510 and a second region 520 surrounding the first region 510. It can be understood that the first region 510 and the second region 520 are both three-dimensional regions, which can extend in a direction perpendicular to the upper surface of the substrate 500. Corresponding to the first region 510, the semiconductor stack 100 is arranged above the substrate 500. From top to bottom, the semiconductor stack 100 and the substrate 500 are sequentially stacked with the insulating layer 200, the first bonding layer 300 and the second bonding layer 400, and the insulating layer 200, the first bonding layer 300 and the second bonding layer 400 all extend from the first region 510 to the second region 520. The inner side wall of the conductive hole 101 is sequentially provided with the insulating layer 200, the metal layer 600 and the first bonding layer 300 from outside to inside, and the metal layer 600 is also arranged at the contact position of the conductive hole 101 and the first semiconductor layer 110, so as to realize the electrical connection between the metal layer 600 and the first semiconductor layer 110. After the insulating layer 200 and the metal layer 600 are arranged on the side wall of the conductive hole 101 and the metal layer 600 is arranged at the contact position of the conductive hole 101 and the first semiconductor layer 110, the first bonding layer 300 is filled in the remaining space of the conductive hole 101, and the first bonding layer 300 is electrically connected to the first semiconductor layer 110 through the metal layer 600.

[0077] In an optional embodiment, as shown in Figure 3As shown, the insulating layer 200 arranged between the transparent conductive layer 201 and the metal layer 600 includes a first insulating layer 210 and a second insulating layer 220, the first insulating layer 210 is arranged close to the transparent conductive layer 201, and the second insulating layer 220 is arranged between the first insulating layer 210 and the metal layer 600, that is, from top to bottom, the insulating layer 200 includes the first insulating layer 210 and the second insulating layer 220 which are sequentially stacked. Corresponding to the region of the semiconductor stack 100 except the conductive hole 101, the first insulating layer 210 is provided with a through hole 211 penetrating the first insulating layer 210, and a metal reflection layer 202 is arranged between the first insulating layer 210 and the second insulating layer 220, the metal reflection layer 202 covers the first insulating layer 210 and fills the through hole 211 to be electrically connected with the transparent conductive layer 201. By arranging the through hole 211 in the first insulating layer 210 and filling the metal reflection layer 202 in the through hole 211, the reflectivity of light in the light-emitting diode can be improved, and the luminous brightness of the light-emitting diode can be improved. The metal reflection layer 202 can be formed by at least one metal including Ag, Al, Ni, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au and Hf, the metal reflection layer 202 reflects the light radiated by the semiconductor stack 100 towards the side of the metal reflection layer 202 back to the semiconductor stack 100, and radiates out from the light-emitting side of the semiconductor stack 100, thereby improving the luminous brightness of the light-emitting diode.

[0078] In an optional embodiment, as shown in Figure 3 The metal reflection layer 202 and the second insulating layer 220 are provided with a metal protection layer 203, the metal protection layer 203 covers from the first region 510 to the second region 520, and the material of the metal protection layer 203 can be Pt, Au, TiW, Cr and other passivation metal materials. The second insulating layer 220 wraps the sidewall of the metal protection layer 203 to protect the metal protection layer 203.

[0079] In an optional embodiment, as shown in Figure 3 Corresponding to the second region 520, the first insulating layer 210 has an interrupted region, and the interrupted region is provided with an electrode 700, and the electrode 700 is electrically connected with the metal protection layer 203. The electrode 700 can be a P electrode, and the material of the P electrode can be Ti, Pt, Ni, Au, Sn and the like.

[0080] In an optional embodiment, as shown in Figure 3 The surface of the first semiconductor layer 110 away from the active layer 120 is a rough surface, which is beneficial to the light-emitting effect of the light-emitting diode.

[0081] In an optional embodiment, as shown in Figure 3As shown, a passivation layer 800 is provided on the sidewall of the electrode 700 and the sidewall of the semiconductor stack 100, and the passivation layer 800 provides insulation protection for the light-emitting diode.

[0082] Example 2

[0083] This embodiment provides a method for fabricating a light-emitting diode, referring to... Figures 4 to 10 The method for fabricating a light-emitting diode in this embodiment includes the following steps:

[0084] S1, such as Figure 4 As shown, a substrate 900 is provided.

[0085] The substrate 900 is a substrate 900 for growing the semiconductor stack 100, and can be a sapphire substrate, silicon nitride substrate, silicon substrate, gallium nitride substrate or aluminum nitride substrate, etc.

[0086] S2, such as Figure 4 As shown, a first semiconductor layer 110, an active layer 120, and a second semiconductor layer 130 are sequentially grown on the upper surface of the substrate 900.

[0087] The first semiconductor layer 110 can be an N-type semiconductor layer, the active layer 120 can be a quantum well layer, and the second semiconductor layer 130 can be a P-type semiconductor layer.

[0088] S3, such as Figure 4 As shown, along a direction perpendicular to the substrate 900, the second semiconductor layer 130, the active layer 120, and at least a portion of the first semiconductor layer 110 are etched to form at least one conductive hole 101.

[0089] In an optional embodiment, step S3 further includes the following steps:

[0090] like Figure 5 As shown, a transparent conductive layer 201 is formed on the second semiconductor layer 130 surrounding the conductive hole 101. The region where the transparent conductive layer 201 and the conductive hole 101 are located is defined as the first region 510, and the region surrounding the transparent conductive layer 201 is defined as the second region 520. Figure 5 The second region 520 marked in the text is only a part of the second region and is not fully marked.

[0091] S4. Corresponding to the first region 510 and the second region 520, an insulating layer 200 and a first bonding layer 300 are sequentially formed on the second semiconductor layer 130, and an insulating layer 200 and a first bonding layer 300 are sequentially formed from the outside to the inside on the inner sidewall of the conductive hole 101. The first bonding layer 300 passes through the conductive hole 101 and is electrically connected to the first semiconductor layer 110.

[0092] In an optional embodiment, step S4 specifically includes the following steps:

[0093] S410, such as Figure 5 As shown, a first insulating layer 210 is formed on the sidewall of the conductive hole 101, above the transparent conductive layer 201, and above the second semiconductor layer 130 of the second region 520; the portion of the first insulating layer 210 in the first region 510 other than the conductive hole 101 is etched to expose the transparent conductive layer 201, forming at least one through hole 211.

[0094] S420, such as Figure 6 As shown, corresponding to the first region 510, a metal reflective layer 202 is formed on the first insulating layer 210 surrounding the conductive hole 101. The metal reflective layer 202 simultaneously fills the through hole 211 and is electrically connected to the transparent conductive layer 201.

[0095] S430, such as Figure 6 As shown, a metal protective layer 203 is formed above the metal reflective layer 202, and the metal protective layer 203 extends into a portion of the second region 520.

[0096] S440, such as Figure 7 As shown, the second insulating layer 220 covers the first insulating layer 210 on the sidewall of the conductive hole 101 and is formed above the metal protective layer 203 and above the first insulating layer 210 formed in the second region 520.

[0097] S450, such as Figure 7 As shown, the metal layer 600 is formed above the second insulating layer 220, and the metal layer 600 covers the second insulating layer 220 on the sidewall of the conductive hole 101 and is formed at the bottom of the conductive hole 101, so as to realize the electrical connection between the metal layer 600 and the first semiconductor layer 110.

[0098] S460, such as Figure 7 As shown, the first bonding layer 300 is formed above the metal layer 600, and the first bonding layer 300 covers the metal layer 600 of the conductive hole 101 and fills the conductive hole 101.

[0099] S5, such as Figure 7 As shown, corresponding to the conductive via 101 region, the first bonding layer 300 has a hole 301; as Figure 8 As shown, a repair layer 302 is formed on the upper surface of the first bonding layer 300 from the first region 510 to the second region 520.

[0100] S6, such as Figure 9 As shown, a repair layer 302 is etched except for the corresponding conductive hole 101. The thermal conductivity of the repair layer 302 is greater than that of the first bonding layer 300, and the hardness of the repair layer 302 is greater than that of the first bonding layer 300.

[0101] Optionally, the upper surface of the repair layer 302 is flush with the upper surface of the first bonding layer 300.

[0102] Optionally, the material of the repair layer 302 is diamond, and the repair layer 302 is formed by electron cyclotron resonance-chemical vapor deposition.

[0103] Optionally, the material of the repair layer 302 is diamond-like carbon, and the repair layer 302 is formed by sputtering.

[0104] S7, as shown in the figure, a substrate 500 is provided, and the substrate 500 is bonded to the first bonding layer 300 through the second bonding layer 400. Figure 10

[0105] Optionally, after step S7, the following steps are further included:

[0106] S8, the substrate 900 is removed to expose the first semiconductor layer 110.

[0107] S9, corresponding to the second region, the first semiconductor layer 110, the active layer 120, and the second semiconductor layer 130 are etched to stop at the surface of the first insulating layer 210, and the unetched first semiconductor layer 110, the active layer 120, and the second semiconductor layer 130 form a semiconductor stack 100 corresponding to the first region 510.

[0108] S10, roughen the surface of the first semiconductor layer 110 of the semiconductor stack 100 away from the active layer 120.

[0109] S11, etch part of the first insulating layer 210 in the second region 520 to expose the metal protection layer 203, form an interruption region, and form an electrode 700 in the interruption region, and the electrode 700 is electrically connected to the metal protection layer 203.

[0110] S12, form a passivation layer 800 on the sidewall of the semiconductor stack 100, the sidewall of the electrode 700, and the surface of the first insulating layer 210 in the second region 520 except the interruption region.

[0111] Embodiment three

[0112] The embodiment provides a light emitting device, as shown in the figure. Figure 11 ​As shown, the light emitting device includes a circuit board 10 and a plurality of light emitting elements 20 disposed on the circuit board 10, the light emitting elements 20 including the light emitting diode of embodiment one or the light emitting diode prepared by the preparation method of embodiment two. The light emitting diode of embodiment one or the light emitting diode prepared by the preparation method of embodiment two includes a repair layer disposed in the hole 301 of the first bonding layer 300 corresponding to the area of the conductive hole 101, effectively improving the porosity in the first bonding layer 300, improving the reliability of the light emitting diode; at the same time, the thermal conductivity of the repair layer 302 is greater than that of the first bonding layer 300, improving the efficiency of heat conduction from the first bonding layer 300 to the surrounding environment, effectively reducing the risk of local hot spots, and improving the performance of the light emitting diode; the hardness of the repair layer 302 is greater than that of the first bonding layer 300, improving the mechanical strength of the first bonding layer 300, and improving the durability and reliability of the light emitting diode.

[0113] The above-mentioned light emitting device can be used for lighting of vehicles, handheld devices, stage lights, etc., and can improve the reliability, stability and durability of the above-mentioned devices.

[0114] The above-mentioned embodiments only exemplarily illustrate the principles and effects of the present application, and are not used to limit the present application. Any person skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical idea of the present application should be covered by the claims of the present application.

Claims

1. A light emitting diode, characterized by, The application relates to a semiconductor stack, a conductive hole, a substrate and a repair layer. The semiconductor stack comprises, from top to bottom, a first semiconductor layer, an active layer and a second semiconductor layer which are sequentially stacked; At least one conductive hole is arranged in the semiconductor stack, the conductive hole penetrates the second semiconductor layer, the active layer and at least part of the first semiconductor layer, and the inner side wall of the conductive hole is sequentially provided with an insulating layer and a first bonding layer, the first bonding layer is electrically connected with the first semiconductor layer through the conductive hole; The substrate is bonded with the first bonding layer through a second bonding layer; Corresponding to the lower area of the conductive hole, the first bonding layer has a hole, and the repair layer is arranged in the hole, the thermal conductivity of the repair layer is greater than that of the first bonding layer, and the hardness of the repair layer is greater than that of the first bonding layer.

2. The light emitting diode of claim 1, wherein, The repair layer has insulation.

3. The light emitting diode of claim 1, wherein, The hole is a regular or irregular hole naturally formed due to the height difference after the first bonding layer fills the conductive hole.

4. The light emitting diode according to claim 1 or 2, wherein The surface of the repair layer close to the second bonding layer is flush with the surface of the first bonding layer close to the second bonding layer.

5. The light emitting diode according to claim 1 or 2, wherein The absolute value of the height difference between the surface of the repair layer close to the second bonding layer and the surface of the first bonding layer close to the second bonding layer is less than 0.1 mu m.

6. The light emitting diode of claim 1, wherein, The aperture of the conductive hole gradually increases from the first semiconductor layer to the second semiconductor layer, corresponding to the lower area of the maximum aperture of the conductive hole, the vertical projection area of the first bonding layer on the second bonding layer is greater than the vertical projection area of the repair layer on the second bonding layer.

7. The light emitting diode of claim 6, wherein, Corresponding to the lower area of the maximum aperture of the conductive hole, the width of the repair layer is equal to the sum of twice the width of the first bonding layer and the maximum aperture of the conductive hole.

8. The light emitting diode of claim 1, wherein, The distance between the centers of two adjacent conductive holes is less than or equal to 200 mu m.

9. The light emitting diode of claim 1, wherein, The distance between the edges of two adjacent repair layers is less than or equal to 180 mu m.

10. The light emitting diode of claim 1, wherein, The thermal conductivity of the repair layer is between 500 W / m.K and 2200 W / m.K, and the Vickers hardness is between 20 Gpa and 200 Gpa. The material of the repair layer is diamond or diamond-like carbon.

11. The light emitting diode of claim 1 or 2, wherein, The inner side wall of the conductive hole is further provided with a metal layer, the metal layer is arranged between the insulating layer and the first bonding layer, and the metal layer is electrically connected with the first semiconductor layer through the conductive hole.

12. The light emitting diode of claim 1, wherein, The surface of the substrate close to the second bonding layer comprises a first area and a second area, and the second area surrounds the first area; 13. The light emitting diode of claim 12, wherein, Corresponding to the first area, the semiconductor stack is arranged above the substrate; From top to bottom, the semiconductor stack and the substrate are sequentially stacked with the insulating layer, the first bonding layer and the second bonding layer; the second bonding layer, the first bonding layer and the insulating layer all cover from the first area to the second area. The surface of the second semiconductor layer away from the active layer is provided with a transparent conductive layer, and the transparent conductive layer is arranged between the second semiconductor layer and the insulating layer.

14. The light emitting diode of claim 13, wherein, ​ From top to bottom, the insulating layer comprises a first insulating layer and a second insulating layer; corresponding to the area covered by the second semiconductor layer, the first insulating layer is provided with a through hole, a metal reflecting layer is arranged between the first insulating layer and the second insulating layer, the metal reflecting layer covers the first insulating layer and fills the through hole to be electrically connected with the transparent conductive layer; a metal protective layer is arranged between the metal reflecting layer and the second insulating layer, the metal protective layer covers from the first area to the second area, and the second insulating layer wraps the sidewall of the metal protective layer.

15. The light emitting diode of claim 14, wherein, Corresponding to the second area, the first insulating layer has an interrupted area, the interrupted area is provided with an electrode, and the electrode is electrically connected with the metal protective layer.

16. A light emitting device comprising: The application relates to a circuit board and a plurality of light emitting elements arranged on the circuit board, the light emitting elements comprising the light emitting diode of any one of claims 1-15.

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