Light emitting diode and light emitting device

Abstract

The invention provides a light emitting diode and a light emitting device. The light-emitting diode comprises a substrate, a semiconductor laminated layer, an insulating layer, a first electrode layer, a first adhesion layer and a second adhesion layer, the semiconductor laminated layer comprises a second semiconductor layer, an active layer and a first semiconductor layer which are sequentially laminated from the upper surface of the substrate; at least one groove is formed in the semiconductor lamination layer, and the insulating layer is arranged between the substrate and the semiconductor lamination layer and at least covers the side wall of the groove; the first electrode layer is arranged between the substrate and the insulating layer, is at least arranged on the side wall and the bottom wall of the groove, and is electrically connected with the first semiconductor layer; the first adhesion layer is arranged between the first electrode layer and the insulating layer and is at least arranged on the side wall of the groove; the second adhesion layer is arranged between the first electrode layer and the first adhesion layer and is at least arranged on the side wall and the bottom wall of the groove. The first adhesion layer is arranged between the insulating layer and the first electrode layer, so that the occurrence proportion of black spots in the groove is reduced, and the yield and reliability of the light emitting diode are improved.

Description

Technical Field

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

[0002] With the continuous advancement of gallium nitride (GaN) material preparation technology, GaN-based light-emitting diode (LED) devices have been widely used in many fields. GaN-based LEDs have shown great potential and market value in many fields such as lighting, display, and communication due to their high brightness, low power consumption, and long life. However, in high-end application fields, the performance requirements for LEDs are becoming increasingly stringent, and the market demand for LED products with high light efficiency, low energy consumption, and high reliability is growing.

[0003] In terms of improving the photoelectric conversion efficiency of LEDs, an important research direction is to improve the electrode design of LED chips. At present, in order to meet the market demand for high-efficiency LEDs, the N-type electrodes of vertical and flip-chip GaN-based LED chips usually use Ag (silver) materials instead of traditional Al (aluminum) materials 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 LED performance, in the actual production process, it faces the problem of abnormal black spots in the N electrode hole. These black spots not only affect the appearance quality of the LED chip, but also may become a potential risk point for device failure, resulting in reduced light efficiency and shortened life. Summary of the invention

[0005] In view of the defects and shortcomings of light-emitting diodes in the prior art, the present application provides a light-emitting diode and a light-emitting device to improve the problem of abnormal black spots in N-electrode holes and improve the yield and reliability of light-emitting diodes.

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

[0007] A substrate having a first surface and a second surface disposed opposite to each other;

[0008] A semiconductor stack, the semiconductor stack is arranged above the first surface, and includes 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 is arranged in the semiconductor stack, and the groove passes through the second semiconductor layer, the active layer and at least a portion of the first semiconductor layer;

[0009] An insulating layer, the insulating layer is disposed between the substrate and the semiconductor layer stack and at least covers the sidewall of the groove;

[0010] A first electrode layer, wherein the first electrode layer is disposed between the substrate and the insulating layer and is at least disposed on the sidewall and the bottom wall of the groove and is electrically connected to the first semiconductor layer;

[0011] a first adhesion layer, wherein the first adhesion layer is disposed between the first electrode layer and the insulating layer and is at least disposed on a sidewall of the groove;

[0012] A second adhesion layer is disposed between the first electrode layer and the first adhesion layer and is at least disposed on a side wall and a bottom wall of the groove.

[0013] According to another embodiment of the present application, a light-emitting device is provided, including a circuit board and a plurality of light-emitting units arranged on the circuit board, wherein the light-emitting units include the light-emitting diodes 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 provides a first adhesion layer between at least the first electrode layer and the insulating layer in the groove of the semiconductor stack, thereby ensuring the reflectivity of the first electrode layer while improving the adhesion between the first electrode layer and the insulating layer in the groove, reducing the proportion of black spots in the groove, and enhancing the yield and reliability of the light-emitting diode. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The figure shows a top view of a light emitting diode in the prior art in which a black spot appears in the N-electrode hole.

[0017] Figure 2 The diagram shows a schematic top view of a light emitting diode in the prior art.

[0018] Figure 3 Display as Figure 2 Schematic diagram of the cross-sectional structure along the AA direction.

[0019] Figure 4 Shown is a schematic cross-sectional structure diagram of a light emitting diode provided in Example 1 of the present application.

[0020] Figure 5 Shown is a schematic cross-sectional structure diagram of a light emitting diode provided in the second embodiment of the present application.

[0021] Figure 6 Shown is a schematic diagram of the cross-sectional structure of a light emitting diode provided in Example 3 of the present application.

[0022] Figure 7 Shown is a schematic cross-sectional structure diagram of another light emitting diode provided in the third embodiment of the present application.

[0023] Figure 8 Shown is a schematic cross-sectional structure diagram of yet another light emitting diode provided in the third embodiment of the present application.

[0024] Fig. 9 Shown is a schematic diagram of the cross-sectional structure of a light emitting diode provided in Example 4 of the present application.

[0025] Fig.10 Shown is a schematic diagram of the cross-sectional structure of a light emitting diode provided in Example 5 of the present application.

[0026] Fig.11 Shown is a schematic diagram of the structure of the light-emitting device provided in Example 6 of the present application.

[0027] Component number description

[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 turning region; 302, second height turning region; 310, first insulating layer; 320, second insulating layer; 410, first electrode layer; 420, second adhesion layer; 500, first adhesion 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 following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0030] In order to improve the reflection of light, the N electrode of the vertical structure chip or flip-chip structure chip can use the Ag material layer instead of the Al material layer. However, after using this design, Figure 1 As shown in the figure, a certain proportion of black spots will appear in the N electrode hole of the LED chip, which will cause the LED chip to have yield loss and reliability concerns. The following is a specific analysis of the reasons for the appearance of black spots in the N electrode hole. Figure 2 and Figure 3The figure shows a vertical structure chip in the prior art, wherein the insulating layer 300 in the groove 201 serves to separate the P / N currents. When the first electrode layer 410 is made of an Ag material layer, since the adhesion between the insulating layer 300 and the Ag material layer is very poor, a Cr material layer is usually covered in front of the Ag material layer to increase its adhesion with 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 coating process, in order to ensure the reflectivity of the first electrode layer 410, only a very thin Cr material layer can be covered in front of the Ag material layer. When the Cr material layer is thin, for example, at a position where the height difference with the semiconductor stack 200 platform is large, such as the groove 201, the Cr material layer has poor coverage on the side wall, which will easily cause the first electrode layer 410 on the side wall of the groove 201 to directly contact the insulating layer 300. In the subsequent bonding process, affected by factors such as bonding temperature and pressure, Ag migration and loss occur in the Ag material layer, thereby causing the groove 201 to turn black.

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

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

[0033] A semiconductor stack, the semiconductor stack is arranged above the first surface, and includes 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 is arranged in the semiconductor stack, and the groove passes through the second semiconductor layer, the active layer and at least a portion of the first semiconductor layer;

[0034] An insulating layer, the insulating layer is disposed between the substrate and the semiconductor stack and at least covers a sidewall of the groove;

[0035] A first electrode layer, the first electrode layer is disposed between the substrate and the insulating layer and is at least disposed on the sidewall and the bottom wall of the groove to form an electrical connection with the first semiconductor layer;

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

[0037] The second adhesion layer is disposed between the first electrode layer and the first adhesion layer and is at least disposed on the side wall and the bottom wall of the groove.

[0038] The light-emitting diode provided in this embodiment provides a first adhesion layer at least between the first electrode layer and the insulating layer in the groove, thereby ensuring the reflectivity of the first electrode layer and improving the adhesion between the first electrode layer and the insulating layer in the groove, reducing the blackening phenomenon in the groove caused by Ag migration and loss of the first electrode layer, reducing the proportion of black spots in the groove, improving the stability of 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 disposed below the second semiconductor layer outside the groove;

[0040] The first adhesion layer is also disposed below the insulating layer outside the groove;

[0041] The second adhesive layer is also disposed below the first adhesive layer outside the groove;

[0042] The first electrode layer is also disposed below the second adhesion layer outside the groove.

[0043] The light-emitting diode of this embodiment is provided with a first adhesion layer and a second adhesion layer between the first electrode layer and the insulating layer both inside and outside the groove, thereby further increasing the adhesion between the first electrode layer and the insulating layer, thereby improving production stability and reliability of the light-emitting diode.

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

[0045] The first adhesion layer is also partially disposed below the insulating layer outside the groove;

[0046] The second adhesive layer is also disposed below a portion of the first adhesive layer outside the groove and below a portion of the insulating layer outside the groove that is not covered by the first adhesive layer;

[0047] The first electrode layer is also disposed below the second adhesion layer outside the groove.

[0048] The light-emitting diode of this embodiment has only a portion of the first adhesion layer disposed outside the groove. On the one hand, if the material of the first adhesion layer used has light-absorbing properties, the coverage of the first adhesion layer can be reduced, thereby achieving the purpose of brightening. On the other hand, if the material of the first adhesion layer used is a metal material, the amount of the first adhesion layer used can be reduced, thereby reducing costs.

[0049] In some embodiments, a second electrode layer is disposed in a partial area below 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 groove, the second insulating layer is disposed between the first insulating layer and the first adhesion layer;

[0052] The second insulating layer is further disposed below the second electrode layer and below the second semiconductor layer outside the groove where the second electrode layer is not disposed;

[0053] A first height turning area is formed between a lower surface of the second insulating layer disposed below the second semiconductor layer and a lower surface of the second insulating layer disposed below the second electrode layer;

[0054] The first adhesion layer is also disposed below the first height turning area.

[0055] The light-emitting diode of this embodiment sets the first adhesion layer in the place with relatively large height difference in the first electrode layer coverage area, for example: in the groove and the first height turning area. Due to the large height difference, the Cr material layer in this area often has poor coverage. Therefore, the adhesion between the first electrode layer and the second insulating layer in this area can be improved, the delamination or peeling phenomenon can be reduced, and the long-term stability and reliability of the light-emitting diode can be improved.

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

[0057] The first insulating layer extends from the sidewall of the groove to cover the outer side below the transparent conductive layer;

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

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

[0060] A second height turning area is formed between the lower surface of the second insulating layer located below the reflective layer and the lower surface of the second insulating layer located outside the reflective layer and not below the reflective layer;

[0061] The first adhesion layer is also disposed below the second height turning area.

[0062] In this embodiment, the first adhesion layer is set in the groove, the first height turning area, and the second height turning area, which are locations with large height differences in the areas covered by the first electrode layer, to further improve the adhesion between the first electrode layer and the second insulating layer, reduce the delamination or peeling of the first electrode layer, improve the production yield of the light-emitting diode, and improve the long-term stability and reliability of the light-emitting diode.

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

[0064] The first adhesion layer is also disposed below the insulating layer outside the groove;

[0065] The second adhesive layer extends from the sidewall of the groove to outside the groove, and is partially disposed below the first adhesive layer outside the groove;

[0066] The first electrode layer is also disposed below the second adhesion layer outside the groove.

[0067] The light-emitting diode of this embodiment can be provided with a second adhesion layer and a first electrode layer only in a partial area outside the groove and in the groove. On the one hand, if the first electrode layer is provided on the entire surface outside the groove, the first electrode layer will leak out at the edge of the light-emitting diode. At the same time, due to the relatively poor stability of the first electrode layer, it is easy to be corroded under salt spray environment conditions; on the other hand, since the material of the first electrode layer is relatively soft, when the first electrode layer is squeezed, the first electrode layer will be displaced, resulting in problems such as uneven film thickness, film peeling and film voids in the first electrode layer. The first electrode layer in the partial area inside and 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 voids in the first electrode layer, and improve the performance and reliability of the light-emitting diode; at the same time, by providing the first adhesion layer in the entire area inside and outside the groove, the edge of the first electrode layer can be coated to prevent the active metal of the first electrode layer from overflowing.

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

[0069] The first adhesion layer extends from the sidewall of the groove to outside the groove, and is partially disposed below the insulating layer outside the groove;

[0070] The second adhesive layer is also disposed below a portion of the first adhesive layer located outside the groove;

[0071] The first electrode layer is also disposed below a portion of the second adhesion layer outside the groove.

[0072] The light-emitting diode of this embodiment is provided with the first adhesion layer only in a partial area outside the groove and in the groove, that is, the first adhesion layer at least covers the position with the height difference, and other positions without the height difference may not be covered by the first adhesion layer. In this way, the adhesion force between the first electrode layer and the insulating layer is improved while controlling the amount and range of coverage of the first adhesion layer, 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 reliability of the light-emitting diode.

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

[0074] The light emitting diode of this embodiment controls the thickness of the first adhesion layer, thereby ensuring the adhesion between the first electrode layer and the insulating layer while using an appropriate amount of the first adhesion layer.

[0075] In some embodiments, the thickness of the second adhesion layer is no greater than 2 nm.

[0076] The light-emitting diode of this embodiment controls the thickness of the second adhesion layer to be no more than 2 nm, which can ensure the adhesion between the first electrode layer and the insulating layer while avoiding reducing the reflectivity of the first electrode layer, thereby improving the light-emitting brightness and reliability of the light-emitting diode.

[0077] In some embodiments, the material of the first adhesion 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 brightness of the light-emitting diode and reduce the production cost, in this embodiment, when the material of the first adhesion layer is selected from materials that do not absorb light or basically do not absorb light, such as aluminum oxide, magnesium oxide, tantalum oxide, silicon nitride, etc., the thickness of the first adhesion layer is preferably set to less than 10nm; when the material of the first adhesion layer is selected from transparent conductive oxides, in order to avoid the first adhesion layer absorbing light, the thickness of the first adhesion layer is preferably set to less than 5nm; when the material of the first adhesion layer is selected from metal materials such as aluminum, aluminum-silver alloy, titanium, titanium-tungsten alloy, chromium or nickel, the thickness of the first adhesion layer is preferably set to less than 2nm.

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

[0080] The material of the second adhesion layer in the light-emitting diode of this embodiment is a Cr-containing material layer, which can further increase the adhesion between the first electrode layer and the insulating layer. However, the Cr material layer needs to be set to a suitable thickness to ensure 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 Ag-containing material layer in direct contact with the second adhesion layer.

[0082] The first electrode layer of the light emitting diode of this embodiment adopts a silver-containing material layer, and the first electrode layer is in direct contact with the second adhesion layer, which can improve the reflection of light generated in the active layer of the light emitting diode, thereby improving the photoelectric conversion efficiency of the light emitting diode.

[0083] In some embodiments, the light emitting diode further includes a bonding layer, and the bonding layer of the substrate is connected to the semiconductor stack; the bonding layer extends into the groove 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 bonds the substrate and the semiconductor layer stack, and fills the remaining space in the groove to reduce the height difference in the groove, thereby improving the mechanical stability and reliability of the light-emitting diode.

[0085] Another embodiment of the present application provides a light-emitting device, including a circuit board and a plurality of light-emitting units arranged on the circuit board, wherein the light-emitting units include the light-emitting diodes provided in the present application.

[0086] The light emitting device includes the light emitting diode, and thus also has the advantages of 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 reliability.

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

[0088] Embodiment 1

[0089] This embodiment provides a light emitting diode, such as Figure 4 As shown, the light emitting diode includes a substrate 100 , a semiconductor stack 200 , an insulating layer 300 , a first electrode layer 410 , a first adhesion layer 500 and a second adhesion layer 420 .

[0090] The substrate 100 has a first surface and a second surface that are arranged opposite to each other, and has the function of providing mechanical support for the structure on the first surface thereof, and also has the function of heat dissipation. The substrate 100 may be a conductive substrate, and the conductive substrate is used to provide electrical connection, and its material may be, for example, silicon, silicon carbide, or metal, and the metal may be, for example, Ni, Au, Cu, Mo, Pd, In, W, Ta, Nb, or alloys of the aforementioned 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, and the active layer 220 is continuously 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 an N-type semiconductor layer and the second semiconductor layer 230 is a P-type semiconductor layer. At this time, the first semiconductor layer 210 provides electrons by doping with an N-type dopant, and the N-type dopant may be, for example, Si, Ge, Sn, Se, Te, etc.; the second semiconductor layer 230 provides holes by doping with a P-type dopant, and the P-type dopant may be, for example, Mg, Zn, Ca, Sr, Ba, etc. A rough structure (not shown in the figure) may be formed on the upper surface of the first semiconductor layer 210. The rough structure may improve the external quantum efficiency and help improve the light emitting effect of the light emitting diode. The active layer 220 is the main region where the light emitting diode emits light, and provides radiation for the recombination of electrons and holes. The active layer 220 may be a single quantum well structure or a multiple quantum well (MQWs) structure. The multiple quantum well structure is formed by alternating stacking of quantum well layers and quantum barrier layers to form a periodic multilayer structure. The quantum barrier layer has a larger band gap than the quantum well layer. The quantum well layer and the quantum barrier layer may be, for example, a GaN layer, an AlGaN layer, or an AlGaInP layer. In order to improve the luminous efficiency of the active layer 220, it may be achieved by changing the depth of the quantum well, the number of layers of the paired quantum well layers and quantum barrier layers, the thickness, and / or other features in the active layer 220.

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

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

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

[0095] The second adhesion layer 420 and the first electrode layer 410 are used simultaneously and have the same coverage. The second adhesion layer 420 is in direct contact with the first adhesion layer 500 and is at least arranged on the first adhesion layer 500 in the groove 201 and on the bottom wall in 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 adhesion layer 420 and is at least disposed on the second adhesion layer 420 in the groove 201 . The second adhesion layer 420 and the first electrode layer 410 are electrically connected to the first semiconductor layer 210 .

[0097] The light emitting diode of this embodiment has the first adhesive layer 500, the second adhesive layer 420 and the first electrode layer 410 at least arranged in the groove 201, and while ensuring the reflectivity of the first electrode layer 410, it can enhance the adhesion between the first electrode layer 410 and the insulating layer 300 in the groove 201, reduce the blackening phenomenon in the groove 201 caused by the migration and loss of Ag in the first electrode layer 410, reduce the proportion of black spots in the groove 201, improve the stability in the production process and the consistency of the product, and improve the yield and reliability of the light emitting diode. At the same time, since the first electrode layer 410 is only arranged in the groove 201, it can improve the uniformity of the thickness of the first electrode layer 410, reduce the peeling of the first electrode layer 410, reduce the phenomenon of voids in the groove 201, and further improve 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, thereby enhancing the adhesion between the first electrode layer 410 and the insulating layer 300 without affecting other properties of the light-emitting diode. The material of the first adhesion layer 500 can be selected from aluminum oxide (Al2O3), magnesium oxide (MgO), tantalum oxide (Ta2O5), silicon nitride (SiN x ), transparent conductive oxide, aluminum (Al), aluminum silver alloy (AlAg), titanium (Ti), titanium tungsten alloy (TiW), chromium (Cr) or nickel (Ni), etc., wherein 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 x), the thickness of the first adhesion layer 500 is preferably set to be no greater than 10 nm. When the material of the first adhesion layer 500 is selected from a transparent conductive oxide, in order to prevent the first adhesion layer 500 from absorbing light, the thickness of the first adhesion layer 500 is preferably set to be no greater than 5 nm. When the material of the first adhesion layer 500 is selected from a metal material such as aluminum (Al), aluminum-silver alloy (AlAg), titanium (Ti), titanium-tungsten alloy (TiW), chromium (Cr), nickel (Ni), etc., the thickness of the first adhesion layer 500 is preferably set to be no greater than 2 nm.

[0099] In an optional embodiment, if Figure 4 As shown, corresponding to the area where the second semiconductor layer 230 is located, a second electrode layer 600 is disposed in a partial area below the second semiconductor layer 230 , and a 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] In 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 at least arranged below the second semiconductor layer 230 that does not cover the second electrode layer 600, and the total thickness of the second electrode layer 600 is greater than the thickness of the first insulating layer 310, so 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 arranged below the second electrode layer 600 and below the first insulating layer 310 that does not cover the second electrode layer 600 outside the groove 201; since the thickness of the second electrode layer 600 is greater than the thickness of the first insulating layer 310, the thickness of the second insulating layer 320 is uniform, so two height turning regions are formed on the lower surface of the second insulating layer 320, namely the first height turning region 301 and the second height turning region 302, the first height turning region 301 is close to the side wall of the groove 201, and the second height turning region 302 is far away from the side wall of the groove 201.

[0103] Outside the groove 201, the first adhesive layer 500 is disposed in the area between the first height turning area 301 and the sidewall of the groove 201, the second adhesive layer 420 is disposed below the first adhesive layer 500, and the first electrode layer 410 is disposed below the second adhesive layer 420. The first adhesive layer 500 is disposed in the groove 201 and the first height turning area 301, which are locations with a large height difference. In this way, the adhesion between the first electrode layer 410 and the insulating layer 300 is improved while controlling the amount and range covered by the first adhesive layer 500, that is, without affecting other properties of the light-emitting diode.

[0104] In an optional embodiment, if Figure 4 As shown, the second adhesion layer 420 is also disposed below the first adhesion layer 500 outside the groove 201 ; the first electrode layer 410 is also disposed below the second adhesion layer 420 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 in sequence 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 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, for example, 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), IrO x 、RuO x 、RuO x / TO, Ni / IrOx / Au, Ni / IrO x At least one of / Au / ITO.

[0107] The 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 has the function of reflecting the light radiated from the semiconductor stack 200 toward the side of the substrate 100, so that the light returns to the semiconductor stack 200 and radiates out from the light emitting side, thereby improving the light emitting 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 on the lower surface of the transparent conductive layer 610, and a plurality of through holes can be formed on the first insulating layer 310 in the corresponding area, the through holes penetrate the first insulating layer 310, and then the reflective layer 620 is formed on the lower surface of the first insulating layer 310 in the corresponding area. The reflective layer 620 is also filled in the through holes to form a CBL structure to improve the current distribution, improve the luminous efficiency, and improve the heat dissipation performance. The material of the reflective layer 620 is selected from at least one metal selected from Ag, Al, Ni, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au and Hf.

[0108] The protective layer 630 is disposed on the lower surface of the reflective layer 620 and wraps the side wall of the reflective layer 620. The protective layer 630 has the function of preventing the metal of the reflective layer 620 from diffusing to other film layers on the side of the protective layer 630 away from the reflective layer 620, thereby preventing the reflection effect from being affected. The material of the protective layer 630 may be, for example, a passivation metal material such as Pt, Au, TiW, Cr, etc. Part of the protective layer 630 extends to cover the outside of the semiconductor stack 200, and the part of the protective layer 630 located outside the semiconductor stack 200 is exposed, and a first electrode 800 is formed on the exposed part. The first electrode 800 may have a polarity opposite to that of the first electrode layer 410. When the first electrode 800 is a P electrode, the first electrode layer 410 uses an N electrode material. At this time, the material of the first electrode 800 may be, for example, Ti, Pt, Ni, Au, Sn, etc.

[0109] The second insulating layer 320 is arranged 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 arranged. Since the reflective layer 620 is arranged to protrude from the lower surface of the first insulating layer 310, and the thickness of the second insulating layer 320 is consistent in the entire area, the second insulating layer 320 forms a first height turning area 301 close to the side wall of the groove 201 and a second height turning area 302 away from the side wall 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 not more than 2 nm. Preferably, the thickness range of the second adhesion layer 420 is not more than 1.5 nm, for example, the thickness of the second adhesion layer 420 is 0.5 nm, 0.7 nm, 1 nm, 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 directly in contact with the second adhesion layer 420. The first electrode layer 410 is used as a reflective electrode layer, and its material is, for example, selected from Ag or an alloy formed by Ag and at least one metal material of 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, in order to ensure the reflectivity of the electrode, it is necessary to control the thickness of the second adhesion layer 420.

[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 via the bonding layer 700, the bonding layer 700 extends into the groove 201, and is electrically connected to the first semiconductor layer 210 via the first electrode layer 410. The material of the bonding layer 700 is a metal material, for example, may include at least one of Au, Sn, Ti, Ni, Pt and alloys thereof.

[0112] Embodiment 2

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

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

[0115] Embodiment 3

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

[0117] The insulating layer 300 is also disposed below the second semiconductor layer 230 outside the groove 201; the first adhesive layer 500 is also partially disposed below the insulating layer 300 outside the groove 201; the second adhesive layer 420 is also disposed below the first adhesive layer 500 outside the groove 201, and below the insulating layer 300 outside the groove 201 that is not covered by the first adhesive layer 500; the first electrode layer 410 is also disposed below the second adhesive layer 420 outside the groove 201. The partial area outside the groove 201 covered by the first adhesive layer 500 at least includes a position with a relatively large height difference, for example, Figure 5 As shown, the first adhesive layer 500 covers the groove 201 and the first height turning area 301; Figure 6 As shown, the first adhesion layer 500 covers the groove 201, the first height turning area 301, and the second height turning area 302. Due to the large height difference, the Cr material layer in this area often has poor coverage, so the adhesion between the first electrode layer 410 and the second insulating layer 320 in this area can be improved, the delamination or peeling phenomenon can be reduced, and the long-term stability and reliability of the light-emitting diode can be improved. The reason why the first adhesion layer 500 can be left uncovered at other locations without height differences is: on the one hand, if the material of the first adhesion layer 500 used is a light-absorbing material such as a transparent conductive oxide, reducing the coverage of the first adhesion layer 500 can achieve the purpose of brightening; on the other hand, if the material of the first adhesion layer 500 used is a metal material, reducing the amount of the first adhesion layer 500 used can reduce costs.

[0118] In an optional embodiment, if Figure 8As shown, the first adhesive layer 500 may not be arranged outside the groove 201, but only on the side wall of the groove 201; the second adhesive layer 420 extends from the side wall of the groove 201 to cover the outside of the groove 201, and is arranged below the second insulating layer 320 outside the groove 201; the first electrode layer 410 is arranged below the second adhesive layer 420 outside the groove 201 in addition to being arranged on the side wall of the groove 201. In this way, the first adhesive layer 500 is only arranged at such a place in the groove 201 where the height difference is very large, so as to enhance the adhesion between the first electrode layer 410 and the second insulating layer 320. In this way, the amount and range covered by the first adhesive layer 500 are controlled to improve the adhesion between the first electrode layer 410 and the insulating layer 300 without affecting other properties of the light-emitting diode.

[0119] Embodiment 4

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

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

[0122] The first electrode layer 410 is disposed in a partial area outside the groove 201. On the one hand, if the first electrode layer 410 is plated on the entire surface, the first electrode layer 410 will leak out at the edge of the chip, and the Ag material in the first electrode layer 410 has poor stability (more active than Al), and is prone to corrosion in a smoky environment. On the other hand, since the material of the first electrode layer 410 is relatively soft, when the bonding layer 700 squeezes the first electrode layer 410, the first electrode layer 410 will be displaced, resulting in uneven film thickness, film peeling, and voids in the first electrode layer 410. Disposing the first electrode layer 410 only in the groove 201 and partially outside the groove 201 can improve the uniformity of the thickness of the first electrode layer 410, reduce the peeling of the first electrode layer 410, reduce the phenomenon of voids in the first electrode layer 410, and improve the performance and reliability of the light-emitting diode.

[0123] When the entire surface is covered with the first adhesive layer 500 , the first adhesive layer 500 and the bonding layer 700 wrap the edge of the first electrode layer 410 to prevent the active metal in the first electrode layer 410 from overflowing.

[0124] Embodiment 5

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

[0126] like Fig.10 As shown, a first electrode 800 and a second electrode 900 are provided, and the first electrode 800 and the second electrode 900 are both facing upward. The first electrode 800 and the second electrode 900 have opposite polarities. In this embodiment, the first electrode 800 is a P electrode and the second electrode 900 is an N electrode for illustration. 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. The substrate 100 in this embodiment can be an insulating substrate, which is often 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 range of the first adhesion layer 500, the first electrode layer 410 and the second adhesion layer 420 can refer to the first to fourth embodiments. Fig.10 The first electrode layer 410 and the second adhesion layer 420 shown may cover the entire chip, and the first adhesion layer 500 covers the groove 201 , the first height turning area 301 , and the second height turning area 302 .

[0128] Embodiment 6

[0129] This embodiment provides a light emitting device, such as Fig.11 As shown, it includes a circuit board 10 and a plurality of light-emitting units 20 arranged on the circuit board 10, and the light-emitting units 20 include the light-emitting diodes provided in embodiments 1 to 5. The light-emitting diodes in embodiments 1 to 5 are provided with a first adhesion layer 500 between the insulating layer 300 and the first electrode layer 410, and the adhesion between the first electrode layer 400 and the insulating layer 300 is enhanced while ensuring the reflectivity of the first electrode layer 410, thereby reducing the proportion of black spots in the groove 201 and improving the yield and reliability of the light-emitting diodes. The light-emitting unit 20 of this embodiment is beneficial to improving the yield and reliability of the light-emitting device by adopting the light-emitting diodes provided in embodiments 1 to 5.

[0130] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may 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 a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A light emitting diode, characterized in that: include: A substrate having a first surface and a second surface disposed opposite to each other; A semiconductor stack, the semiconductor stack is arranged above the first surface, and includes 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 is arranged in the semiconductor stack, and the groove passes through the second semiconductor layer, the active layer and at least a portion of the first semiconductor layer; An insulating layer, the insulating layer is disposed between the substrate and the semiconductor stack and at least covers a sidewall of the groove; A first electrode layer, the first electrode layer is disposed between the substrate and the insulating layer and is at least disposed on the sidewall and the bottom wall of the groove to form an electrical connection with the first semiconductor layer; a first adhesion layer, wherein the first adhesion layer is disposed between the first electrode layer and the insulating layer and is at least disposed on a sidewall of the groove; The second adhesion layer is disposed between the first electrode layer and the first adhesion layer and is at least disposed on the side wall and the bottom wall of the groove.

2. The light emitting diode according to claim 1, characterized in that: The insulating layer is also disposed below the second semiconductor layer outside the groove; The first adhesion layer is also disposed below the insulating layer outside the groove; The second adhesive layer is also disposed below the first adhesive layer outside the groove; The first electrode layer is also disposed below the second adhesion layer outside the groove.

3. The light emitting diode according to claim 1, characterized in that: The insulating layer is also disposed below the second semiconductor layer outside the groove; The first adhesion layer is also partially disposed below the insulating layer outside the groove; The second adhesive layer is also disposed below the first adhesive layer outside the groove and below the insulating layer outside the groove that is not covered by the first adhesive layer; The first electrode layer is also disposed below the second adhesion layer outside the groove.

4. The light emitting diode according to claim 1, characterized in that: A second electrode layer is disposed in a partial area below the second semiconductor layer corresponding to the area where the second semiconductor layer is located; The insulating layer comprises a first insulating layer and a second insulating layer; In the groove, the second insulating layer is disposed between the first insulating layer and the first adhesion layer; The second insulating layer is further disposed below the second electrode layer and below the second semiconductor layer outside the groove where the second electrode layer is not disposed; A first height turning area is formed between a lower surface of the second insulating layer disposed below the second semiconductor layer and a lower surface of the second insulating layer disposed below the second electrode layer; The first adhesion layer is also disposed below the first height turning area.

5. The light emitting diode according to claim 4, characterized in that: The second electrode layer includes a transparent conductive layer, a reflective layer, and a protective layer stacked in sequence from top to bottom; The first insulating layer extends from the sidewall of the groove to cover the outer side below the transparent conductive layer; The lower surface of the reflective layer is located below the lower surface of the first insulating layer and extends to cover a portion of the lower surface of the first insulating layer; The protective layer is located between the reflective layer and the second insulating layer; A second height turning area is formed between the lower surface of the second insulating layer below the reflective layer and the lower surface of the second insulating layer not below the reflective layer; The first adhesion layer is also disposed below the second height turning area.

6. The light emitting diode according to claim 1, characterized in that: The insulating layer is also disposed below the second semiconductor layer outside the groove; The first adhesion layer is also disposed below the insulating layer outside the groove; The second adhesive layer extends from the sidewall of the groove to outside the groove, and is partially disposed below the first adhesive layer outside the groove; The first electrode layer is also disposed below the second adhesion layer outside the groove.

7. The light emitting diode according to claim 1, characterized in that: The insulating layer is also disposed below the second semiconductor layer outside the groove; The first adhesion layer extends from the sidewall of the groove to outside the groove, and is partially disposed below the insulating layer outside the groove; The second adhesive layer is also disposed below a portion of the first adhesive layer located outside the groove; The first electrode layer is also disposed below a portion of the second adhesion layer outside the groove.

8. The light emitting diode according to any one of claims 1 to 7, characterized in that: The thickness of the first adhesion layer is in the range of 0.2 nm to 50 nm.

9. The light emitting diode according to any one of claims 1 to 7, characterized in that: The thickness of the second adhesion layer is no greater than 2 nm.

10. The light emitting diode according to any one of claims 1 to 7, characterized in that: The material of the first adhesion 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, characterized in that: The material of the second adhesion layer is a Cr-containing material layer.

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

13. The light emitting diode according to any one of claims 1 to 7, characterized in that: The substrate also includes a bonding layer, wherein the bonding layer is connected to the semiconductor stack; the bonding layer extends into the groove and forms an electrical connection with the first semiconductor layer through the first electrode layer.

14. A light emitting device, characterized in that: It comprises a circuit board and a plurality of light-emitting units arranged on the circuit board, wherein the light-emitting units comprise the light-emitting diodes according to any one of claims 1 to 13.

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