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 substrate, a semiconductor stack, an insulating layer, a first electrode layer, a first adhesive layer and a second adhesive layer; the semiconductor stack comprises a second semiconductor layer, an active layer and a first semiconductor layer which are sequentially stacked from the upper surface of the substrate; at least one recess is arranged in the semiconductor stack, the insulating layer is arranged between the substrate and the semiconductor stack and covers at least the sidewall of the recess; the first electrode layer is arranged between the substrate and the insulating layer and is arranged at least on the sidewall and the bottom wall of the recess and is electrically connected with the first semiconductor layer; the first adhesive layer is arranged between the first electrode layer and the insulating layer and is arranged at least on the sidewall of the recess; the second adhesive layer is arranged between the first electrode layer and the first adhesive layer and is arranged at least on the sidewall and the bottom wall of the recess. By arranging the first adhesive layer between the insulating layer and the first electrode layer, the proportion of black spots in the recess is reduced, and the yield 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] With the continuous progress of gallium nitride (GaN) material preparation technology, gallium nitride (GaN) based light emitting diode (LED) devices have been widely used in many fields. GaN-based LED has great potential and market value in lighting, display, communication and other fields due to its high brightness, low power consumption, long service life and other characteristics. However, in the field of high-end applications, the performance requirements of LED are becoming more and more strict, and the market demand for high luminous efficiency, low energy consumption and high reliability LED products is increasing.

[0003] In terms of improving the photoelectric conversion efficiency of LED, an important research direction is to improve the electrode design of LED chip. At present, in order to meet the market demand for high luminous efficiency LED, the N-type electrode of GaN-based LED chip with vertical structure and flip-chip structure usually uses Ag (silver) material instead of traditional Al (aluminum) material to enhance the reflection of light generated in the multi-quantum well (MQW), thereby improving the photoelectric conversion efficiency of the device.

[0004] Although the use of this design has achieved certain results in improving the performance of LED, but in the actual production process, it faces the problem of black point abnormality in the N electrode hole. These black points not only affect the appearance quality of LED chip, but also may become a potential risk point of device failure, leading to light efficiency decline and service life shortening. SUMMARY

[0005] In view of the defects and deficiencies of the prior art light emitting diode, the present application provides a light emitting diode and a light emitting device to improve the problem of black point abnormality in the N electrode hole, and improve the yield and reliability of the light emitting diode.

[0006] An embodiment of the present application provides a light emitting diode, comprising:

[0007] a substrate, the substrate having a first surface and a second surface arranged opposite to each other;

[0008] a semiconductor layer stack, the semiconductor layer stack being arranged above the first surface and comprising a second semiconductor layer, an active layer and a first semiconductor layer stacked in sequence from the first surface; at least one groove, the groove being arranged in the semiconductor layer stack and penetrating the second semiconductor layer, the active layer and at least part of the first semiconductor layer;

[0009] an insulating layer disposed between the substrate and the semiconductor layer stack and covering at least the side wall of the recess;

[0010] a first electrode layer disposed between the substrate and the insulating layer and disposed at least on the side wall and the bottom wall of the recess and electrically connected to the first semiconductor layer;

[0011] a first adhesive layer disposed between the first electrode layer and the insulating layer and disposed at least on the side wall of the recess;

[0012] a second adhesive layer disposed between the first electrode layer and the first adhesive layer and disposed at least on the side wall and the bottom wall of the recess.

[0013] According to another embodiment of the present application, a light emitting device is provided, comprising a circuit board and a plurality of light emitting units disposed on the circuit board, the light emitting units comprising the light emitting diode as described in the present application.

[0014] As described above, the light emitting diode and the light emitting device of the present application have the following beneficial effects:

[0015] The light emitting diode of the present application improves the adhesion between the first electrode layer and the insulating layer in the recess of the semiconductor stack by disposing the first adhesive layer between the first electrode layer and the insulating layer in the recess, thereby ensuring the reflectivity of the first electrode layer, reducing the proportion of black spots in the recess, and enhancing the yield and reliability of the light emitting diode. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 A top view showing black spots in the N electrode hole of a light emitting diode in the prior art.

[0017] Figure 2 A top view showing the structure of a light emitting diode in the prior art.

[0018] Figure 3 A cross-sectional view showing Figure 2 a cross-sectional view along the A-A direction.

[0019] Figure 4 A cross-sectional view showing a light emitting diode according to Embodiment One of the present application.

[0020] Figure 5 A cross-sectional view showing a light emitting diode according to Embodiment Two of the present application.

[0021] Figure 6 A cross-sectional view showing a light emitting diode according to Embodiment Three of the present application.

[0022] Figure 7 A cross-sectional structure schematic diagram of another light emitting diode provided in Embodiment Three of the present application is shown.

[0023] Figure 8 A cross-sectional structure schematic diagram of still another light emitting diode provided in Embodiment Three of the present application is shown.

[0024] Figure 9 A cross-sectional structure schematic diagram of a light emitting diode provided in Embodiment Four of the present application is shown.

[0025] Figure 10 A cross-sectional structure schematic diagram of a light emitting diode provided in Embodiment Five of the present application is shown.

[0026] Figure 11 A structure schematic diagram of a light emitting device provided in Embodiment Six of the present application is shown.

[0027] Element number explanation

[0028] 10, circuit board; 20, light emitting element; 100, substrate; 200, semiconductor stack; 201, groove; 210, first semiconductor layer; 220, active layer; 230, second semiconductor layer; 300, insulating layer; 301, first height transition region; 302, second height transition region; 310, first insulating layer; 320, second insulating layer; 410, first electrode layer; 420, second adhesive layer; 500, first adhesive layer; 600, second electrode layer; 610, transparent conductive layer; 620, reflective layer; 630, protective layer; 700, bonding layer; 800, first electrode; 900, second electrode. DETAILED DESCRIPTION

[0029] The present application is described in detail below by specific specific examples, and other advantages and effects of the present application can be easily understood by those skilled in the art from the disclosure of the present specification. The present application can also be implemented or applied by other different specific embodiments, and various modifications or changes can be made to the details in the present specification based on different views and applications without departing from the spirit of the present application.

[0030] In order to improve light reflection, the N electrode of the vertical structure chip or the flip chip can use an Ag material layer instead of an Al material layer, but after using this design, as shown in Figure 1 , black spots will appear in a certain proportion in the N electrode hole of the LED chip, which will cause yield loss and reliability concerns of the LED chip. The reasons for the appearance of black spots in the N electrode hole are analyzed in detail below, Figure 2 , and Figure 3As shown in a vertical structure chip in the prior art, the insulating layer 300 in the groove 201 functions to separate P / N current. When the first electrode layer 410 adopts an Ag material layer, since the adhesion of the insulating layer 300 and the Ag material layer is poor, a Cr material layer is usually covered in front of the Ag material layer to increase the adhesion of the Ag material layer and the insulating layer 300. According to actual research, the greater the thickness of the Cr material layer, the lower the reflectivity of the N electrode. Therefore, in the actual plating process, in order to ensure the reflectivity of the first electrode layer 410, a very thin Cr material layer is usually covered in front of the Ag material layer. When the Cr material layer is thin, for example, at positions with large height difference from the platform of the semiconductor stack 200 such as the groove 201, the Cr material layer has poor coverage on the sidewall, which will easily cause the Ag material layer of the first electrode layer 410 to directly contact the insulating layer 300 on the sidewall of the groove 201. Due to the influence of bonding temperature and pressure and other reasons in the subsequent bonding process, Ag migration and loss in the Ag material layer will occur, thereby causing the groove 201 to become black.

[0031] Based on the background art and the technical defects described above, the present application provides a light emitting diode, comprising:

[0032] a substrate having a first surface and a second surface arranged opposite to each other;

[0033] a semiconductor stack arranged above the first surface, comprising a second semiconductor layer, an active layer and a first semiconductor layer sequentially stacked from the first surface; at least one groove arranged in the semiconductor stack, and the groove penetrates through the second semiconductor layer, the active layer and at least part of the first semiconductor layer;

[0034] an insulating layer arranged between the substrate and the semiconductor stack, and covering at least the sidewall of the groove;

[0035] a first electrode layer arranged between the substrate and the insulating layer, and arranged at least on the sidewall and the bottom wall of the groove, and forming an electrical connection with the first semiconductor layer;

[0036] a first adhesion layer arranged between the first electrode layer and the insulating layer, and arranged at least on the sidewall of the groove;

[0037] a second adhesion layer arranged between the first electrode layer and the first adhesion layer, and arranged at least on the sidewall and the bottom wall of the groove.

[0038] The light emitting diode provided by the embodiment sets the first adhesive layer between the first electrode layer and the insulating layer in the groove, thereby improving the adhesion between the first electrode layer and the insulating layer in the groove, reducing the blackening phenomenon of the first electrode layer in the groove caused by Ag migration and loss, reducing the proportion of black spots in the groove, improving the stability in the production process and the consistency of the product, and enhancing the yield and reliability of the light emitting diode.

[0039] In some embodiments, the insulating layer is further arranged below the second semiconductor layer outside the groove;

[0040] The first adhesive layer is further arranged below the insulating layer outside the groove;

[0041] The second adhesive layer is further arranged below the first adhesive layer outside the groove;

[0042] The first electrode layer is further arranged below the second adhesive layer outside the groove.

[0043] The light emitting diode of the embodiment further sets the first adhesive layer and the second adhesive layer between the first electrode layer and the insulating layer in the groove and outside the groove, thereby further increasing the adhesion between the first electrode layer and the insulating layer, improving the production stability and the reliability of the light emitting diode.

[0044] In some embodiments, the insulating layer is further arranged below the second semiconductor layer outside the groove;

[0045] The first adhesive layer is further arranged below the insulating layer outside the groove;

[0046] The second adhesive layer is further arranged below part of the first adhesive layer outside the groove and below the insulating layer outside the groove which is not covered by the first adhesive layer;

[0047] The first electrode layer is further arranged below the second adhesive layer outside the groove.

[0048] The light emitting diode of the embodiment sets only part of the first adhesive layer outside the groove. On the one hand, if the material of the first adhesive layer has light absorption characteristics, the coverage range of the first adhesive layer can be reduced to achieve the purpose of brightening. On the other hand, if the material of the first adhesive layer is a metal material, the use amount of the first adhesive layer can be reduced to reduce the cost.

[0049] In some embodiments, a second electrode layer is arranged below part of the area of the second semiconductor layer corresponding to the area where the second semiconductor layer is located;

[0050] The insulating layer comprises a first insulating layer and a second insulating layer;

[0051] In the recess, the second insulating layer is arranged between the first insulating layer and the first adhesive layer;

[0052] The second insulating layer is also arranged below the second electrode layer and below the second semiconductor layer outside the recess where the second electrode layer is not arranged;

[0053] A first height transition region is formed between the lower surface of the second insulating layer arranged below the second semiconductor layer and the lower surface of the second insulating layer arranged below the second electrode layer;

[0054] The first adhesive layer is also arranged below the first height transition region.

[0055] The light-emitting diode of the embodiment can improve the adhesion between the first electrode layer and the second insulating layer in the area with a large height difference, such as the recess and the first height transition region, by arranging the first adhesive layer in the area, thereby reducing the delamination or peeling phenomenon and improving the long-term stability and reliability of the light-emitting diode.

[0056] In some embodiments, the second electrode layer comprises, from top to bottom, a transparent conductive layer, a reflective layer, and a protective layer;

[0057] The first insulating layer extends from the side wall of the recess to cover the outside below the transparent conductive layer;

[0058] The lower surface of the reflective layer is below the lower surface of the first insulating layer and extends to cover part of the lower surface of the first insulating layer;

[0059] The protective layer is between the reflective layer and the second insulating layer;

[0060] A second height transition region is formed between the lower surface of the second insulating layer below the reflective layer and the lower surface of the second insulating layer below the reflective layer outside;

[0061] The first adhesive layer is also arranged below the second height transition region.

[0062] The first adhesive layer is arranged at the position with large height difference in the groove, the first height transition region and the second height transition region, thereby further improving the adhesion between the first electrode layer and the second insulating layer, reducing the delamination or peeling of the first electrode layer, improving the production yield of the light emitting diode and improving the long-term stability and reliability of the light emitting diode.

[0063] In some embodiments, the insulating layer is further arranged under the second semiconductor layer outside the groove;

[0064] The first adhesive layer is further arranged under the insulating layer outside the groove;

[0065] The second adhesive layer extends from the groove sidewall to outside the groove and is partially arranged under the first adhesive layer outside the groove;

[0066] The first electrode layer is further arranged under the second adhesive layer outside the groove.

[0067] The light emitting diode of the embodiment can arrange the second adhesive layer and the first electrode layer only in the groove and in the partial region outside the groove. On the one hand, if the first electrode layer is arranged on the whole surface outside the groove, the first electrode layer will leak out at the edge of the light emitting diode, and the first electrode layer is prone to corrosion in the salt spray environment due to the poor stability of the first electrode layer. On the other hand, the first electrode layer is soft, and the first electrode layer will be displaced when being pressed, which will cause the problems of uneven thickness, peeling and cavities of the first electrode layer. The first electrode layer in the groove and in the partial region outside the groove can improve the uniformity of the thickness of the first electrode layer, reduce the peeling of the first electrode layer, reduce the phenomenon of cavities of the first electrode layer, and improve the performance and reliability of the light emitting diode. Meanwhile, the first adhesive layer arranged on the whole surface in the groove and outside the groove can cover the edge of the first electrode layer to prevent the active metal of the first electrode layer from overflowing.

[0068] In some embodiments, the insulating layer is further arranged under the second semiconductor layer outside the groove;

[0069] The first adhesive layer extends from the groove sidewall to outside the groove and is partially arranged under the insulating layer outside the groove;

[0070] The second adhesive layer is further arranged under part of the first adhesive layer outside the groove;

[0071] The first electrode layer is further arranged under part of the second adhesive layer outside the groove.

[0072] The light emitting diode of the embodiment sets the first adhesive layer only in the area outside the groove and in the groove, that is, the first adhesive layer covers at least the position with height difference, and the position without height difference can not be covered by the first adhesive layer. In this way, the amount and range of the first adhesive layer are controlled, the adhesion between the first electrode layer and the insulating layer is improved, the proportion of black spots in the groove is reduced, the stability in the production process and the consistency of the product are improved, and the reliability of the light emitting diode is enhanced.

[0073] In some embodiments, the thickness of the first adhesive layer ranges from 0.2 nm to 50 nm.

[0074] The light emitting diode of the embodiment controls the thickness of the first adhesive layer, so that the appropriate amount of the first adhesive layer is used while the adhesion between the first electrode layer and the insulating layer is ensured.

[0075] In some embodiments, the thickness of the second adhesive layer is not greater than 2 nm.

[0076] The light emitting diode of the embodiment controls the thickness of the second adhesive layer to be not greater than 2 nm, so that the adhesion between the first electrode layer and the insulating layer is ensured while the reflectivity of the first electrode layer is not reduced, thereby improving the luminous brightness and the reliability of the light emitting diode.

[0077] In some embodiments, the material of the first adhesive layer is selected from aluminum oxide, magnesium oxide, tantalum oxide, silicon nitride, transparent conductive oxide, aluminum, aluminum-silver alloy, titanium, titanium-tungsten alloy, chromium, or nickel.

[0078] In order to ensure the luminous brightness of the light emitting diode and reduce the production cost, when the material of the first adhesive layer is selected from non-light-absorbing or substantially non-light-absorbing materials such as aluminum oxide, magnesium oxide, tantalum oxide, and silicon nitride, the thickness of the first adhesive layer is preferably set to be below 10 nm; when the material of the first adhesive layer is selected from transparent conductive oxide, in order to avoid light absorption of the first adhesive layer, the thickness of the first adhesive layer is preferably set to be below 5 nm; when the material of the first adhesive layer is selected from metal materials such as aluminum, aluminum-silver alloy, titanium, titanium-tungsten alloy, chromium, or nickel, the thickness of the first adhesive layer is preferably set to be below 2 nm.

[0079] In some embodiments, the material of the second adhesive layer is a Cr-containing material layer.

[0080] The material of the second adhesive layer in the light emitting diode of the embodiment is a Cr-containing material layer, which can further increase the adhesion between the first electrode layer and the insulating layer, but the Cr-containing material layer needs to be set to an appropriate thickness to ensure the adhesion while avoiding reducing the reflectivity of the first electrode layer.

[0081] In some embodiments, the first electrode layer is a multi-layer metal structure, and the first electrode layer includes a layer of Ag-containing material in direct contact with the second adhesive layer.

[0082] The first electrode layer of the light emitting diode of the present embodiment employs a layer of Ag-containing material, and the first electrode layer is in direct contact with the second adhesive layer, which can improve the reflection of light generated in the active layer of the light emitting diode, and further improve the photoelectric conversion efficiency of the light emitting diode.

[0083] In some embodiments, the light emitting diode further includes a bonding layer, the bonding layer is connected with the semiconductor stack of the substrate; the bonding layer extends into the recess, and forms an electrical connection with the first semiconductor layer through the first electrode layer.

[0084] The bonding layer of the light emitting diode of the present embodiment connects the substrate and the semiconductor stack, and fills the remaining space in the recess, so as to reduce the height difference in the recess, and improve the mechanical stability and reliability of the light emitting diode.

[0085] Another embodiment of the present application provides a light emitting device, which includes a circuit board and a plurality of light emitting units arranged on the circuit board, and the light emitting units include the light emitting diode provided by the present application.

[0086] The light emitting device includes the light emitting diode described above, and thus can also reduce the proportion of black spots in the recess, improve the stability during the production process and the consistency of the product, and enhance the reliability.

[0087] The following will be described in detail through specific embodiments.

[0088] Embodiment One

[0089] The present embodiment provides a light emitting diode, as shown in the figure, which includes a substrate 100, a semiconductor stack 200, an insulating layer 300, a first electrode layer 410, a first adhesive layer 500, and a second adhesive layer 420. Figure 4 The substrate 100 has a first surface and a second surface arranged oppositely, and has the function of providing mechanical support for the structure on the first surface, and also has the function of heat dissipation. The substrate 100 can be a conductive substrate, which is used to provide electrical connection, and the material thereof can be, for example, silicon, silicon carbide, or metal, and the metal can be, for example, Ni, Au, Cu, Mo, Pd, In, W, Ta, Nb, or an alloy of the above-mentioned metal materials.

[0090] The first electrode layer 410 is arranged on the first surface of the substrate 100, and is in direct contact with the first adhesive layer 500. The first electrode layer 410 can be a multi-layer metal structure, and the material thereof can be, for example, Ag, Au, Cu, Mo, Pd, In, W, Ta, Nb, or an alloy of the above-mentioned metal materials.

[0091] A semiconductor stack 200 is disposed above the first surface of the substrate 100. The semiconductor stack 200 includes a first semiconductor layer 210, an active layer 220, and a second semiconductor layer 230. The second semiconductor layer 230 is formed above the first surface of the substrate 100, the active layer 220 is formed on the second semiconductor layer 230, and finally the first semiconductor layer 210 is formed on the active layer 220. The first semiconductor layer 210 and the second semiconductor layer 230 have opposite polarities. In this embodiment, the first semiconductor layer 210 is described as an N-type semiconductor layer and the second semiconductor layer 230 is described as a P-type semiconductor layer. In this case, the first semiconductor layer 210 provides electrons by doping with an N-type dopant, such as Si, Ge, Sn, Se, Te, etc.; the second semiconductor layer 230 provides holes by doping with a P-type dopant, such as Mg, Zn, Ca, Sr, Ba, etc. A rough structure (not shown in the figure) can be formed on the upper surface of the first semiconductor layer 210. This rough structure improves the external quantum efficiency, which is beneficial for enhancing the light emission performance of the LED. The active layer 220 is the main light-emitting region of the LED, providing radiation for electron-hole recombination. The active layer 220 can be a single quantum well structure or a multiple quantum well (MQW) structure. A MQW structure consists of alternating quantum well layers and quantum barrier layers, forming a periodic multilayer structure. The quantum barrier layer has a larger band gap than the quantum well layers. The quantum well layers and quantum barrier layers can be, for example, GaN layers, AlGaN layers, or AlGaInP layers. To improve the luminous efficiency of the active layer 220, the depth of the quantum wells, the number of paired quantum well and quantum barrier layers, the thickness, and / or other characteristics can be modified within the active layer 220.

[0092] At least one groove 201 is provided in the semiconductor stack 200, and the groove 201 penetrates the second semiconductor layer 230, the active layer 220, and at least part of the first semiconductor layer 210.

[0093] An insulating layer 300 is disposed between the substrate 100 and the semiconductor stack 200, and at least covers the sidewalls of the recess 201. The insulating layer 300 is made of an insulating material to separate the P / N currents; the insulating material may be, for example, SiO2, SiN, or SiO2. x N y At least one of TiO2, Si3N4, Al2O3, TiN, AlN, ZrO2, TiAlN, TiSiN, HfO2, TaO2, or MgF2.

[0094] The first adhesive layer 500 is in direct contact with the insulating layer 300 and is disposed at least on the insulating layer 300 located in the groove 201 to increase the adhesion between the insulating layer 300 in the groove 201 and the first electrode layer 410.

[0095] The second adhesive layer 420 and the first electrode layer 410 are used simultaneously and have the same coverage area. The second adhesive layer 420 is in direct contact with the first adhesive layer 500 and is disposed at least on the first adhesive layer 500 located in the groove 201 and on the bottom wall of the groove 201 to increase the adhesion between the insulating layer 300 and the first electrode layer 410.

[0096] The first electrode layer 410 is in direct contact with the second adhesive layer 420 and is at least disposed on the second adhesive layer 420 located in the groove 201. The second adhesive layer 420 and the first electrode layer 410 are electrically connected to the first semiconductor layer 210.

[0097] In this embodiment, the light-emitting diode has at least three layers: a first adhesion layer 500, a second adhesion layer 420, and a first electrode layer 410 disposed within the groove 201. While ensuring the reflectivity of the first electrode layer 410, this arrangement enhances the adhesion between the first electrode layer 410 and the insulating layer 300 within the groove 201, reducing blackening of the first electrode layer 410 within the groove 201 due to Ag migration and loss. This lowers the proportion of black spots within the groove 201, improves stability during production, enhances product consistency, and increases the yield and reliability of the light-emitting diode. Furthermore, since the first electrode layer 410 is only disposed within the groove 201, the uniformity of its thickness is improved, reducing peeling and void formation within the groove 201, further enhancing the performance and reliability of the light-emitting diode.

[0098] In an optional embodiment, the thickness of the first adhesion layer 500 is between 0.2 nm and 50 nm. This enhances the adhesion between the first electrode layer 410 and the insulating layer 300 without affecting other performance characteristics of the light-emitting diode. The material of the first adhesion layer 500 can be selected from alumina (Al₂O₃), magnesium oxide (MgO), tantalum oxide (Ta₂O₅), and silicon nitride (SiN₂). x The materials used include transparent conductive oxides, aluminum (Al), aluminum-silver alloy (AlAg), titanium (Ti), titanium-tungsten alloy (TiW), chromium (Cr), or nickel (Ni), where the transparent conductive oxide can be indium tin oxide (ITO), indium oxide (InO), tin oxide (SnO), zinc oxide (ZnO), indium zinc oxide (IZO), etc. When the material of the first adhesion layer 500 is selected from aluminum oxide (Al2O3), magnesium oxide (MgO), tantalum oxide (Ta2O5), silicon nitride (SiN), etc., the materials can be transparent conductive oxides, aluminum (Al), aluminum-silver alloy (AlAg), titanium (Ti), titanium-tungsten alloy (TiW), chromium (Cr), or nickel (Ni). xWhen the material of the first adhesion layer 500 is selected from materials that do not absorb light or absorb very little light, the thickness of the first adhesion layer 500 is preferably set to no more than 10 nm. When the material of the first adhesion layer 500 is selected from transparent conductive oxides, the thickness of the first adhesion layer 500 is preferably set to no more than 5 nm to avoid light absorption. When the material of the first adhesion layer 500 is selected from metals such as aluminum (Al), aluminum-silver alloy (AlAg), titanium (Ti), titanium-tungsten alloy (TiW), chromium (Cr), and nickel (Ni), the thickness of the first adhesion layer 500 is preferably set to no more than 2 nm.

[0099] In optional embodiments, such as Figure 4 As shown, a second electrode layer 600 is provided in a portion of the area below the second semiconductor layer 230, corresponding to the area where the second semiconductor layer 230 is located. The first electrode 800 disposed on the periphery of the semiconductor stack 200 is electrically connected to the second semiconductor layer 230 through the second electrode layer 600.

[0100] The insulating layer 300 includes a first insulating layer 310 and a second insulating layer 320.

[0101] Within the groove 201, the first insulating layer 310 covers the sidewall of the groove 201, and the second insulating layer 320 covers the first insulating layer 310, that is, the second insulating layer 320 is disposed between the first insulating layer 310 and the first adhesive layer 500.

[0102] Outside the groove 201, the first insulating layer 310 is disposed at least below the second semiconductor layer 230 that does not cover the second electrode layer 600. The total thickness of the second electrode layer 600 is greater than the thickness of the first insulating layer 310. Therefore, the lower surface of the second electrode layer 600 is located below the lower surface of the first insulating layer 310. The second insulating layer 320 is disposed below the second electrode layer 600 and below the first insulating layer 310 outside the groove 201 that does not cover the second electrode layer 600. Since the thickness of the second electrode layer 600 is greater than the thickness of the first insulating layer 310, and the thickness of the second insulating layer 320 is uniform, the lower surface of the second insulating layer 320 forms two height transition regions, namely the first height transition region 301 and the second height transition region 302. The first height transition region 301 is close to the sidewall of the groove 201, and the second height transition region 302 is away from the sidewall of the groove 201.

[0103] Outside the groove 201, a first adhesive layer 500 is disposed in the area between the first height transition region 301 and the sidewall of the groove 201. A second adhesive layer 420 is disposed below the first adhesive layer 500, and a first electrode layer 410 is disposed below the second adhesive layer 420. The first adhesive layer 500 is disposed in locations with significant height differences, such as within the groove 201 and the first height transition region 301. This allows for improved adhesion between the first electrode layer 410 and the insulating layer 300 while controlling the amount and extent of coverage by the first adhesive layer 500—that is, without affecting other performance characteristics of the LED.

[0104] In optional embodiments, such as Figure 4 As shown, the second adhesion layer 420 is also disposed below the first adhesion layer 500 located outside the groove 201; the first electrode layer 410 is also disposed below the second adhesion layer 420 located outside the groove 201.

[0105] In an optional embodiment, the second electrode layer 600 includes a transparent conductive layer 610, a reflective layer 620, and a protective layer 630 stacked sequentially from top to bottom.

[0106] A transparent conductive layer 610 is formed on a portion of the lower surface of the second semiconductor layer 230 located outside the groove 201. The transparent conductive layer 610 is in ohmic contact with the second semiconductor layer 230. The material of the transparent conductive layer 610 is selected from transparent conductive materials, such as indium tin oxide (ITO), indium zinc oxide (IZO), indium zinc tin oxide (IZTO), indium aluminum zinc oxide (IAZO), indium gallium zinc oxide (IGZO), indium gallium tin oxide (IGTO), aluminum zinc oxide (AZO), antimony tin oxide (ATO), gallium zinc oxide (GZO), and IrO. x RuO x RuO x / TO, Ni / IrOx / Au, Ni / IrO x At least one of / Au / ITO.

[0107] A reflective layer 620 is disposed below the lower surface of the transparent conductive layer 610 and extends to cover a portion of the lower surface of the first insulating layer 310. It reflects light radiated from the semiconductor stack 200 toward the substrate 100, causing the light to return to the semiconductor stack 200 and radiate outwards from the light-emitting side, thereby improving the light emission effect of the light-emitting diode. The reflective layer 620 can be in direct contact with the transparent conductive layer 610, or the first insulating layer 310 can be formed first on the lower surface of the transparent conductive layer 610, with multiple through-holes formed in corresponding areas of the first insulating layer 310, penetrating the first insulating layer 310. The reflective layer 620 then fills the through-holes, forming a CBL structure to improve current distribution, increase luminous efficiency, and improve heat dissipation. The reflective layer 620 is formed from at least one metal selected from Ag, Al, Ni, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, and Hf.

[0108] A protective layer 630 is disposed on the lower surface of the reflective layer 620 and encloses the sidewalls of the reflective layer 620. The protective layer 630 prevents the metal of the reflective layer 620 from diffusing to other films on the side of the protective layer 630 away from the reflective layer 620, thus preventing any impact on the reflection effect. The material of the protective layer 630 can be, for example, passivating metal materials such as Pt, Au, TiW, or Cr. A portion of the protective layer 630 extends to cover the outer side of the semiconductor stack 200, with the portion of the protective layer 630 located outside the semiconductor stack 200 exposed, and a first electrode 800 is formed on the exposed portion. The first electrode 800 can have the opposite polarity to the first electrode layer 410. When the first electrode 800 is a P-electrode, the first electrode layer 410 uses an N-electrode material. In this case, the material of the first electrode 800 can be, for example, Ti, Pt, Ni, Au, or Sn.

[0109] The second insulating layer 320 is disposed on the lower surface of the protective layer 630 and on the lower surface of the first insulating layer 310 located outside the groove 201 where the protective layer 630 is not disposed. Since the reflective layer 620 protrudes from the lower surface of the first insulating layer 310 and the thickness of the second insulating layer 320 is consistent throughout the entire area, the second insulating layer 320 forms a first height transition region 301 near the sidewall of the groove 201 and a second height transition region 302 away from the sidewall of the groove 201.

[0110] In an optional embodiment, the material of the second adhesion layer 420 is a Cr-containing material layer, and the thickness of the second adhesion layer 420 is controlled within a range of no more than 2 nm. Preferably, the thickness of the second adhesion layer 420 is no more than 1.5 nm, for example, the thickness of the second adhesion layer 420 is 0.5 nm, 0.7 nm, 1 nm, or 1.2 nm. The first electrode layer 410 is a multilayer metal structure, and the first electrode layer 410 includes an Ag-containing material layer in direct contact with the second adhesion layer 420. The first electrode layer 410 serves as a reflective electrode layer, and its material is, for example, selected from Ag or an alloy formed by Ag and at least one of the following metals: Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, Hf, W, and Ti. Since the greater the thickness of the Cr-containing material layer, the lower the reflectivity of the CrAg layer formed by the first electrode layer 410 and the second adhesion layer 420, it is necessary to control the thickness of the second adhesion layer 420 in order to ensure the reflectivity of the electrode.

[0111] In an optional embodiment, the light-emitting diode further includes a bonding layer 700. The substrate 100 and the semiconductor stack 200 are connected by the bonding layer 700. The bonding layer 700 extends into the groove 201 and forms an electrical connection with the first semiconductor layer 210 through the first electrode layer 410. The material of the bonding layer 700 is a metallic material, such as at least one of Au, Sn, Ti, Ni, Pt, and their alloys.

[0112] Example 2

[0113] This embodiment also provides a light-emitting diode, such as... Figure 5 As shown, the light-emitting diode in this embodiment also includes a substrate 100, a semiconductor stack 200, an insulating layer 300, a first electrode layer 410, a first adhesive layer 500, and a second adhesive layer 420. The difference from Embodiment 1 is that:

[0114] like Figure 5 As shown, the insulating layer 300 is also disposed below the second semiconductor layer 230 located outside the groove 201; the first adhesive layer 500 is also disposed below the insulating layer 300 located outside the groove 201 (specifically below the second insulating layer 320); the second adhesive layer 420 is also disposed below the first adhesive layer 500 located outside the groove 201; and the first electrode layer 410 is also disposed below the second adhesive layer 420 located outside the groove 201. By providing the first adhesive layer 500 and the second adhesive layer 420 both inside and outside the groove 201 between the first electrode layer 410 and the insulating layer 300, the adhesion between the first electrode layer 410 outside the groove 201 and the insulating layer 300 is increased, thereby further improving production stability and the reliability of the light-emitting diode.

[0115] Example 3

[0116] This embodiment also provides a light-emitting diode, such as... Figure 6 and Figure 7 As shown, the light-emitting diode in this embodiment also includes a substrate 100, a semiconductor stack 200, an insulating layer 300, a first electrode layer 410, a first adhesive layer 500, and a second adhesive layer 420. The difference from Embodiment 1 or Embodiment 2 is that:

[0117] The insulating layer 300 is also disposed below the second semiconductor layer 230 located outside the groove 201; the first adhesive layer 500 is also partially disposed below the insulating layer 300 located outside the groove 201; the second adhesive layer 420 is also disposed below the first adhesive layer 500 located outside the groove 201, and below the insulating layer 300 located outside the groove 201 not covered by the first adhesive layer 500; the first electrode layer 410 is also disposed below the second adhesive layer 420 located outside the groove 201. The portion of the area outside the groove 201 covered by the first adhesive layer 500 includes at least locations with significant height differences, for example, such as... Figure 5 As shown, the first adhesive layer 500 covers the groove 201 and the first height transition region 301; as Figure 6 As shown, the first adhesive layer 500 covers the groove 201, the first height transition region 301, and the second height transition region 302. Due to the significant height difference, the Cr material layer in this region often has poor coverage. Therefore, this layer can improve the adhesion between the first electrode layer 410 and the second insulating layer 320 in this region, reducing delamination or peeling and improving the long-term stability and reliability of the LED. The reason why the first adhesive layer 500 can be omitted in other locations without height differences is twofold: firstly, if the material of the first adhesive layer 500 is a light-absorbing material such as a transparent conductive oxide, reducing the coverage area of ​​the first adhesive layer 500 can achieve the purpose of brightening; secondly, if the material of the first adhesive layer 500 is a metallic material, reducing the amount of the first adhesive layer 500 used can reduce costs.

[0118] In optional embodiments, such as Figure 8As shown, the first adhesive layer 500 may not be disposed outside the groove 201, but only on the sidewall of the groove 201; while the second adhesive layer 420 extends from the sidewall of the groove 201 to cover the outside of the groove 201, and is disposed below the second insulating layer 320 outside the groove 201; the first electrode layer 410 is disposed not only on the sidewall of the groove 201, but also below the second adhesive layer 420 outside the groove 201. In this way, the first adhesive layer 500 is disposed only in the groove 201, where the height difference is very large, to enhance the adhesion between the first electrode layer 410 and the second insulating layer 320. By controlling the amount and range covered by the first adhesive layer 500, the adhesion between the first electrode layer 410 and the insulating layer 300 can be improved without affecting other performance characteristics of the light-emitting diode.

[0119] Example 4

[0120] This embodiment also provides a light-emitting diode, such as... Figure 9 As shown, the light-emitting diode in this embodiment also includes a substrate 100, a semiconductor stack 200, an insulating layer 300, a first electrode layer 410, a first adhesive layer 500, and a second adhesive layer 420. The difference from embodiments one to three is that:

[0121] like Figure 7 As shown, the insulating layer 300 is also disposed below the second semiconductor layer 230 located outside the groove 201; the first adhesive layer 500 is also disposed below the insulating layer 300 located outside the groove 201; the second adhesive layer 420 extends from the sidewall of the groove 201 to the outside of the groove 201 and is partially disposed below the first adhesive layer 500 located outside the groove 201; the first electrode layer 410 is also disposed below the second adhesive layer 420 located outside the groove 201.

[0122] The first electrode layer 410 is disposed in a portion of the area outside the groove 201. On the one hand, if the first electrode layer 410 is deposited on the entire surface, it will be exposed at the edge of the chip. The Ag material in the first electrode layer 410 has poor stability (more reactive than Al) and is prone to corrosion under smoky conditions. On the other hand, since the material of the first electrode layer 410 is relatively soft, it will shift when the bonding layer 700 compresses it, resulting in uneven film thickness, peeling, and voids in the film. By disposing of the first electrode layer 410 only inside the groove 201 and part of the outside of the groove 201, the uniformity of the thickness of the first electrode layer 410 can be improved, peeling and voids in the first electrode layer 410 can be reduced, and the performance and reliability of the light-emitting diode can be improved.

[0123] When the first adhesive layer 500 is fully covered, the first adhesive layer 500 and the bonding layer 700 wrap around the edge of the first electrode layer 410 to prevent the active metal in the first electrode layer 410 from spilling out.

[0124] Example 5

[0125] This embodiment also provides a light-emitting diode, such as... Figure 10 As shown, the light-emitting diode in this embodiment also includes a substrate 100, a semiconductor stack 200, an insulating layer 300, a first electrode layer 410, a first adhesive layer 500, and a second adhesive layer 420. The difference from embodiments one to four is that:

[0126] like Figure 10 As shown, a first electrode 800 and a second electrode 900 are provided, both facing upwards. The first electrode 800 and the second electrode 900 have opposite polarities; in this embodiment, the first electrode 800 is described as a P-electrode and the second electrode 900 as an N-electrode. The material of the first electrode 800 can be selected from Ti, Pt, Ni, Au, Sn, etc., and the material of the second electrode 900 can be selected from Al, Ag, Cr, Pt, TiW, etc. In this embodiment, the substrate 100 can be an insulating substrate, which is commonly used to isolate electrical connections and prevent short circuits; for example, it can be a ceramic substrate, a resin substrate, etc.

[0127] In this embodiment, the ranges of the first adhesion layer 500, the first electrode layer 410, and the second adhesion layer 420 can be referred to in Embodiments 1 to 4. Figure 10 The first electrode layer 410 and the second adhesive layer 420 shown can cover the entire chip surface. The first adhesive layer 500 covers the groove 201, the first height transition region 301, and the second height transition region 302.

[0128] Example 6

[0129] This embodiment provides a light-emitting device, such as... Figure 11 As shown, the device includes a circuit board 10 and multiple light-emitting units 20 disposed on the circuit board 10. Each light-emitting unit 20 includes a light-emitting diode (LED) provided in Embodiments 1 to 5. The LEDs in Embodiments 1 to 5, by providing a first adhesion layer 500 between the insulating layer 300 and the first electrode layer 410, enhance the adhesion between the first electrode layer 400 and the insulating layer 300 while maintaining the reflectivity of the first electrode layer 410, thereby reducing the proportion of black spots appearing in the groove 201 and improving the yield and reliability of the LED. The light-emitting unit 20 in this embodiment, by employing the LEDs provided in Embodiments 1 to 5, helps to improve the yield and reliability of the light-emitting device.

[0130] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A light emitting diode, characterized by, The application relates to a substrate, a semiconductor stack, an insulating layer, a first electrode layer, a first adhesive layer and a second adhesive layer. The substrate has a first surface and a second surface arranged oppositely; The semiconductor stack is arranged above the first surface and comprises a second semiconductor layer, an active layer and a first semiconductor layer arranged in sequence from the first surface; At least one groove is arranged in the semiconductor stack and penetrates the second semiconductor layer, the active layer and at least part of the first semiconductor layer; The insulating layer is arranged between the substrate and the semiconductor stack and covers at least the sidewall of the groove; The first electrode layer is arranged between the substrate and the insulating layer and arranged at least on the sidewall and the bottom wall of the groove and electrically connected with the first semiconductor layer; The first adhesive layer is arranged between the first electrode layer and the insulating layer and arranged at least on the sidewall of the groove; 2. The light emitting diode of claim 1, wherein, The second adhesive layer is arranged between the first electrode layer and the first adhesive layer and arranged at least on the sidewall and the bottom wall of the groove. The insulating layer is further arranged below the second semiconductor layer outside the groove; The first adhesive layer is further arranged below the insulating layer outside the groove; The second adhesive layer is further arranged below the first adhesive layer outside the groove and below the insulating layer not covered by the first adhesive layer outside the groove; 3. The light emitting diode of claim 1, wherein, The first electrode layer is further arranged below the second adhesive layer outside the groove. The insulating layer is further arranged below the second semiconductor layer outside the groove; The first adhesive layer is further arranged partially below the insulating layer outside the groove; The second adhesive layer is further arranged below the first adhesive layer outside the groove and below the insulating layer not covered by the first adhesive layer outside the groove; 4. The light emitting diode of claim 1, wherein, The first electrode layer is further arranged below the second adhesive layer outside the groove. A second electrode layer is arranged below part of the area of the second semiconductor layer; The insulating layer comprises a first insulating layer and a second insulating layer; In the groove, the second insulating layer is arranged between the first insulating layer and the first adhesive layer; The second insulating layer is further arranged below the second electrode layer and below the second semiconductor layer not arranged with the second electrode layer outside the groove; A first height transition area is formed between the lower surface of the second insulating layer arranged below the second semiconductor layer and the lower surface of the second insulating layer arranged below the second electrode layer; 5. The light emitting diode of claim 4, wherein, The first adhesive layer is further arranged below the first height transition area. The second electrode layer comprises a transparent conductive layer, a reflective layer and a protective layer arranged in sequence from top to bottom; The first insulating layer extends from the sidewall of the groove to the outside below the transparent conductive layer; The lower surface of the reflective layer is below the lower surface of the first insulating layer and extends to part of the lower surface of the first insulating layer; The protective layer is arranged between the reflective layer and the second insulating layer; A second height transition region is formed between a lower surface of the second insulating layer under the reflective layer and a lower surface of the second insulating layer not under the reflective layer; The first adhesive layer is further disposed under the second height transition region.

6. The light emitting diode of claim 1, wherein, The insulating layer is further disposed under the second semiconductor layer outside the recess; The first adhesive layer is further disposed under the insulating layer outside the recess; The second adhesive layer extends from the sidewall of the recess to outside the recess and is partially disposed under the first adhesive layer outside the recess; The first electrode layer is further disposed under the second adhesive layer outside the recess.

7. The light emitting diode of claim 1, wherein, The insulating layer is further disposed under the second semiconductor layer outside the recess; The first adhesive layer extends from the sidewall of the recess to outside the recess and is partially disposed under the insulating layer outside the recess; The second adhesive layer is further disposed under part of the first adhesive layer outside the recess; The first electrode layer is further disposed under part of the second adhesive layer outside the recess.

8. The light emitting diode according to any one of claims 1 to 7, wherein The thickness of the first adhesive layer ranges from 0.2 nm to 50 nm.

9. The light emitting diode according to any one of claims 1 to 7, wherein The thickness of the second adhesive layer is not greater than 2 nm.

10. The light emitting diode according to any one of claims 1 to 7, wherein The material of the first adhesive layer is selected from aluminum oxide, magnesium oxide, tantalum oxide, silicon nitride, transparent conductive oxide, aluminum, aluminum-silver alloy, titanium, titanium-tungsten alloy, chromium or nickel.

11. The light emitting diode according to any one of claims 1 to 7, wherein The material of the second adhesive layer is a Cr-containing material layer.

12. The light emitting diode according to any one of claims 1 to 7, wherein The first electrode layer is a multi-layer metal structure, and the first electrode layer includes a Ag-containing material layer in direct contact with the second adhesive layer.

13. The light emitting diode according to any one of claims 1 to 7, wherein A bonding layer is further included, the bonding layer is connected to the semiconductor stack of the substrate, the bonding layer extends into the recess and forms an electrical connection with the first semiconductor layer through the first electrode layer.

14. A light-emitting device, characterized in that, A circuit board and a plurality of light emitting units disposed on the circuit board are included, the light emitting units include the light emitting diode of any one of claims 1-13.

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