High-power light-emitting diodes based on diamond patterned substrates and their fabrication methods

Abstract

This invention discloses a high-power nitride light-emitting diode (LED) based on a diamond-based patterned substrate, primarily addressing the problems of poor lattice quality, low light extraction efficiency, insufficient heat dissipation, and complex fabrication processes in existing epitaxial nitride semiconductor LEDs on diamond substrates. From bottom to top, the structure consists of a patterned diamond substrate layer, a boron nitride insertion layer, a nitride material nucleation layer, a nitride buffer layer, and an n-type group III nitride material layer. The upper left portion of this n-type group III nitride material layer contains a group III nitride material quantum well layer, a p-type group III nitride material layer, a transparent conductive layer, and a metal electrode layer; the upper right portion contains the metal electrode layer. This invention utilizes a patterned diamond substrate, improving the substrate's thermal conductivity, light extraction efficiency, and material crystal quality. The addition of a boron nitride insertion layer on the substrate avoids bonding processes, simplifying the device fabrication process. It can be used for high-power lighting, displays, and backlighting.

Description

Technical Field

[0001] This invention belongs to the field of microelectronics technology, and in particular relates to a high-power light-emitting diode that can be used for lighting, display and backlighting. Background Technology

[0002] As the fourth generation of lighting source, nitride light-emitting diodes (LEDs) have advantages such as high efficiency, long lifespan, energy saving, and environmental friendliness. Therefore, the LED industry has become a strategic emerging industry that is of great importance to development both domestically and internationally.

[0003] Group III nitrides, represented by GaN, are an important class of wide-bandgap semiconductor materials. They possess advantages such as high chemical stability, good conductivity, high breakdown voltage, and direct bandgap, making them ideal materials for fabricating semiconductor light-emitting diodes (LEDs). Currently, material preparation processes such as metal-organic chemical vapor deposition (MOCVD) and hydride vapor phase epitaxy (HVA) are relatively mature, enabling the epitaxial growth of nitride materials on substrates with different materials.

[0004] As lighting power continues to increase, the heat generated by LEDs will rise sharply. If this heat is not dissipated in time, the internal heat generated by the LEDs will seriously affect their lifespan and lighting performance. However, sapphire has a low thermal conductivity of only 45 W / mK, which makes it difficult for heat to be transferred quickly, leading to heat accumulation, which greatly affects the performance and lifespan of the device.

[0005] In diamond crystals, each carbon atom forms covalent bonds with four other carbon atoms via sp3 hybrid orbitals, creating a tetrahedron with a bond angle of 109°28' and a bond length of 154 pm. Due to its extremely small bond length, diamond exhibits excellent thermal conductivity, reaching up to 2300 W / mK. Furthermore, because diamond substrates possess extremely high thermal conductivity, this invention utilizes diamond material as a substrate to significantly improve the heat dissipation capacity of the device, solving the problem of insufficient heat dissipation leading to reduced lifespan and performance degradation in high-power light source applications.

[0006] In industrial applications, patterned sapphire substrates are commonly used for nitride light-emitting diodes (LEDs). Due to the significant lattice and thermal mismatch between sapphire and nitride materials, the epitaxial nitride material exhibits high stress and a high density of dislocations. Patterned substrate technology can promote dislocation annihilation and improve light emission efficiency. Correspondingly, fabricating nitride LEDs on patterned diamond substrates can yield semiconductor LEDs with better crystal quality.

[0007] Patent application document CN101692474 discloses "An LED Epitaxial Structure", such as Figure 1As shown, from bottom to top, it includes "a substrate layer 1, a diamond substrate layer 2, a low-temperature GaN buffer layer 3, an N-GaN layer 4, an lnGaN / GaN light-emitting layer 5, a P-GaN layer 6, and a Si / Ni / Be / Au transparent conductive layer 7", among which "diamond substrate layer 2" has a planar structure. LEDs on such planar diamond substrates typically have a high dislocation density, resulting in poor LED luminous performance. Furthermore, such planar diamond substrates are more prone to light leakage, thereby reducing the device's luminous efficiency and increasing energy consumption.

[0008] Patent application document CN105826434B, authorized by the patent office, discloses "A method for fabricating a diamond heat sink GaN-based LED," such as... Figure 2 As shown, the device, from bottom to top, consists of "diamond layer 8, adhesive layer 7, and the remaining GaN-based LED epitaxial material." Its fabrication method involves first epitaxially growing the material on a sapphire substrate, then using a bonding process to transfer the material from the "adhesive layer 7" onto the diamond substrate, thus completing the fabrication of the diamond-based light-emitting diode. This fabrication method is cumbersome, costly, and almost impossible to mass-produce. Summary of the Invention

[0009] The purpose of this invention is to address the shortcomings of traditional high-power light-emitting diodes by proposing a high-power light-emitting diode based on a diamond patterned substrate and its fabrication method, so as to improve the heat dissipation capacity, light extraction efficiency and crystal quality of epitaxial materials, thereby improving the luminous efficiency of the device and reducing the manufacturing cost.

[0010] To achieve the above objectives, the technical solution of the present invention is as follows:

[0011] 1. A high-power nitride light-emitting diode based on a diamond-based patterned substrate, comprising, from bottom to top: a diamond substrate layer 1, a boron nitride insertion layer 2, a nitride material nucleation layer 3, a nitride buffer layer 4, an n-type group III nitride material layer 5, wherein the upper left portion of the n-type group III nitride material layer 5 comprises a group III nitride material quantum well layer 6, a p-type group III nitride material layer 7, a transparent conductive layer 8, and a metal electrode layer 9, and the upper right portion comprises the metal electrode layer 9, characterized in that:

[0012] The diamond substrate 1 has a patterned structure, which is used to improve the crystal quality of subsequent epitaxial materials and the light extraction efficiency of the device.

[0013] A boron nitride insertion layer 2 is added between the nitride material nucleation layer 3 and the diamond substrate layer 1 to eliminate the bonding process in the device fabrication process.

[0014] Furthermore, the patterned structure of the diamond substrate can be any one of a hemispherical, conical, or groove shape.

[0015] Furthermore, the thickness of the boron nitride insertion layer is 1-3 nm; the thickness of the nitride material nucleation layer is 10-50 nm; the thickness of the nitride material buffer layer is 1000-3000 nm; the thickness of the n-type group III nitride material layer is 500-2000 nm; and the thickness of the p-type group III nitride material layer is 50-300 nm.

[0016] Furthermore, the group III nitride material quantum well layer is an ordered structure composed of two alternating group III nitride materials, with a total thickness of 18-180 nm, enabling emission of any specific wavelength from red light to ultraviolet light.

[0017] 2. A method for fabricating a high-power nitride light-emitting diode based on a diamond-based patterned substrate, characterized by comprising the following steps:

[0018] 1) Perform patterning preprocessing on the substrate layer;

[0019] 2) Transfer a layer of boron nitride with a thickness of 1-3 nm onto the pretreated substrate;

[0020] 3) A nitride nucleation layer of 10-50 nm was prepared on a diamond substrate with transferred boron nitride using MOCVD process;

[0021] 4) A 1-3 μm nitride material buffer layer is grown on the nitride material nucleation layer using MOCVD process;

[0022] 5) An n-type nitride material layer of 500-2000 nm was grown on the nitride material buffer layer using MOCVD process.

[0023] 6) Grow 1-10 cycles of group III nitride material quantum well layers on an n-type nitride material layer using MOCVD process, wherein the thickness of each cycle of group III nitride material is 10-18 nm;

[0024] 7) A 50-300 nm p-type nitride material layer was grown on a group III nitride material quantum well layer using MOCVD process;

[0025] 8) A transparent conductive layer is prepared on a p-type nitride material layer by magnetron sputtering;

[0026] 9) Using magnetron sputtering, n-type electrodes were fabricated on n-type nitride materials and p-type electrodes were fabricated on p-type nitride materials to complete the device fabrication.

[0027] Furthermore, step 1) involves patterning the substrate layer as follows:

[0028] 1a) Coat the diamond substrate with photoresist and spread the photoresist evenly on the surface using a spin coater;

[0029] 1b) The diamond substrate uniformly coated with photoresist in 1a) is placed on a high-temperature hot plate for hard film treatment;

[0030] 1c) The substrate that has undergone hard film treatment is placed in a photolithography machine to form a pattern on the photoresist;

[0031] 1d) The photolithographically etched diamond substrate is placed into an etching machine to form a pattern on the diamond substrate;

[0032] 1e) Place the etched diamond substrate in an organic solvent to remove the coated photoresist and complete the substrate patterning preprocessing.

[0033] Furthermore, the boron nitride transfer process in step 2) is implemented as follows:

[0034] 2a) Transferring boron nitride already grown on the surface of a metal catalyst to the surface of an auxiliary organic material;

[0035] 2b) The boron nitride on the surface of the auxiliary organic material is adhered to the diamond substrate;

[0036] 2c) Use organic solvents to dissolve the auxiliary organic materials.

[0037] Compared with the prior art, the present invention has the following advantages:

[0038] First, the present invention uses a patterned diamond substrate, which not only helps to reduce the dislocation density of the material and improve the crystal quality of the device, but also improves the light extraction efficiency of the device, ultimately improving the luminous efficiency of the device, while greatly improving the heat dissipation capacity and ensuring the stability of the device.

[0039] Secondly, by adding a boron nitride insertion layer between the diamond substrate layer and the nitride material buffer layer, the present invention avoids the bonding process required by the prior art, and allows for the direct epitaxy of group III nitride materials on the boron nitride insertion layer, simplifying the manufacturing process and reducing costs. Attached Figure Description

[0040] Figure 1 This is a diagram of an LED epitaxial structure published in the existing patent document CN101692474;

[0041] Figure 2 It is an LED structure diagram disclosed in the existing authorized publication document CN105826434B;

[0042] Figure 3This is a structural diagram of the high-power light-emitting diode based on a diamond patterned substrate according to the present invention;

[0043] Figure 4 This is a flowchart illustrating the fabrication process of a high-power light-emitting diode on a hemispherical diamond patterned substrate.

[0044] Figure 5 This is a flowchart of the fabrication process for a high-power light-emitting diode on a tapered diamond patterned substrate.

[0045] Figure 6 This is a flowchart illustrating the fabrication process of a high-power light-emitting diode (LED) device with a grooved diamond patterned substrate. Detailed Implementation

[0046] The embodiments and effects of the present invention will be further described in detail below with reference to the accompanying drawings:

[0047] Reference Figure 3 The high-power light-emitting diode of the present invention includes a diamond substrate layer 1, a boron nitride insertion layer 2, a nitride material nucleation layer 3, a nitride material buffer layer 4, an n-type group III nitride material layer 5, a group III nitride material quantum well layer 6, a p-type group III nitride material layer 7, a transparent conductive layer 8, and a metal electrode layer 9. Wherein:

[0048] The diamond substrate layer 1 has an unlimited thickness and its surface is patterned, with patterns including but not limited to hemispherical, conical, and grooved shapes. This diamond material has high thermal conductivity, which can improve the heat dissipation capacity of the device. For high-power light-emitting diodes (LEDs), which are characterized by large heat generation, the use of diamond substrate material is beneficial for temperature control, and the device can operate under optimal temperature conditions, thereby increasing its stability and reliability. Since the nitride material system uses heteroepitaxial growth, the mismatch between materials generates a large number of dislocations. The high dislocation density in the top region leads to a decrease in the luminous efficiency of the LED. The pattern fabricated on the substrate surface by photolithography and etching in this invention helps to reduce the dislocation density and improve the crystal quality of the device. That is, the pattern on the substrate can induce the bending of dislocations through the merging process of nucleation islands during epitaxy, thereby preventing dislocations from continuing to extend to the top, reducing the impact of dislocations on the light-emitting area, and improving the luminous efficiency of the device. At the same time, it increases the probability of dislocations merging into rings and annihilating when they meet.

[0049] The boron nitride insertion layer 2 is located on the diamond substrate 1 and has a thickness of 1-3 nm. Since the mismatch between the diamond substrate and the group III nitride material system is extremely large, in order to alleviate this mismatch, the present invention inserts boron nitride between the diamond and the group III nitride material nucleation layer, that is, a boron nitride insertion layer 2 is provided on the upper surface of the diamond substrate 1, which can alleviate this mismatch and facilitate operation.

[0050] The nitride material nucleation layer 3, located above the boron nitride insertion layer 2, has a thickness of 10-50 nm. Its function is to provide nucleation sites for material growth, facilitating the adsorption of atoms and the growth of thin films.

[0051] The nitride material buffer layer 4 is located above the nitride material nucleation layer 3, and its thickness is 1000-3000nm. Its function is to improve the crystal quality of the epitaxial layer and further reduce the dislocation density.

[0052] The n-type group III nitride material layer 5, located above the nitride material buffer layer 4, has a thickness of 500-2000 nm and is used to provide electrons for radiative recombination of the light-emitting diode.

[0053] The group III nitride material quantum well layer 6 is located to the upper left of the n-type group III nitride material layer 5. It is an ordered structure composed of two alternating group III nitride materials with a total thickness of 18-180 nm. It is used for radiative recombination of electrons and holes and is the main light-emitting part of the light-emitting diode.

[0054] The p-type group III nitride material layer 7, located above the group III nitride material quantum well layer 6, has a thickness of 50-300 nm and is used to provide holes for radiative recombination of the light-emitting diode.

[0055] The transparent conductive layer 8 is located on top of the p-type group III nitride material layer 7, and its thickness is unlimited. Its function is to expand the current at the electrode and reduce the current congestion effect.

[0056] The metal electrode layer 9 is configured as two parts, which are located above the transparent conductive layer 8 and to the upper right of the n-type group III nitride material layer 5, respectively, and are used to realize the current exchange between the device and the external circuit.

[0057] This invention provides three embodiments for fabricating high-power light-emitting diodes based on diamond patterned substrates.

[0058] Implementation 1: Fabrication of a high-power InGaN / GaN light-emitting diode based on a hemispherical diamond patterned substrate with a boron nitride thickness of 1 nm.

[0059] Reference Figure 4 The implementation steps for this example are as follows:

[0060] Step one involves photolithography and etching of the diamond substrate to create a hemispherical pattern, such as... Figure 4 a and Figure 4 As shown in b.

[0061] 1.1) Coat the diamond substrate surface with SF6 photoresist and set the spin coater to 4000 rpm to make the photoresist spread evenly on the substrate surface.

[0062] 1.2) A diamond substrate uniformly coated with photoresist is placed on a hot plate at 180°C for hardening treatment, and the hardened substrate is placed in a photolithography machine to form a spherical pattern on the photoresist.

[0063] 1.3) Place the photolithographically etched diamond substrate into an etching machine and form a hemispherical pattern on the diamond substrate by etching;

[0064] 1.4) The etched diamond substrate is placed in an organic solvent to remove the coated photoresist, thus completing the substrate patterning process and obtaining a diamond patterned substrate with a hemispherical pattern on the surface.

[0065] Step two, prepare a boron nitride insertion layer on a diamond substrate, such as... Figure 4 As shown in c.

[0066] 2.1) Transferring boron nitride, which has already been grown on the surface of a metal catalyst, to the surface of polymethyl methacrylate;

[0067] 2.2) Boron nitride on the surface of polymethyl methacrylate is adhered to the diamond substrate;

[0068] 2.3) Use acetone to dissolve polymethyl methacrylate to complete the transfer of boron nitride with a thickness of 1 nm.

[0069] Step 3: Grow a nucleation layer of group III nitride material on the boron nitride insertion layer, such as... Figure 4 As shown in d.

[0070] Ammonia and trimethylaluminum were introduced, and a nitride nucleation layer with a thickness of 30 nm was grown on a hemispherical diamond substrate with a pre-transferred 1 nm thick boron nitride material by MOCVD under process conditions of 1200 °C and 400 Torr in the reaction chamber.

[0071] Step four: Grow a nitride material buffer layer on the nitride material nucleation layer, such as... Figure 4 As shown in e.

[0072] Ammonia and trimethylgallium were introduced, and a nitride material buffer layer with a thickness of 2000 nm was grown on the nitride material nucleation layer by MOCVD under the process conditions of reaction chamber temperature of 1400℃ and pressure of 50 Torr.

[0073] Step 5: Grow an n-type group III nitride material layer on the nitride material buffer layer, such as... Figure 4 As shown in f.

[0074] Ammonia, trimethylgallium, and silane were introduced into the reaction chamber. Under process conditions of 1400℃ and 50 Torr, an n-type nitride material layer with a thickness of 1500 nm was grown on the nitride material buffer layer by MOCVD.

[0075] Step six: Grow a group III nitride quantum well layer on the n-type group III nitride material layer, such as... Figure 4 As shown in g.

[0076] Ammonia, trimethylgallium, and trimethylindium were introduced into the reaction chamber, and a group III nitride quantum well layer with a thickness of 90 nm was grown on an n-type nitride material layer by MOCVD under process conditions of 1000 °C and 40 Torr.

[0077] Step 7: Grow a p-type group III nitride material layer on the group III nitride material quantum well layer, such as... Figure 4 As shown in h.

[0078] Ammonia, trimethylgallium, and magnesium pyrocene were introduced into the reaction chamber. Under process conditions of 950°C and 30 Torr, a 200 nm thick p-type GaN layer was grown on a group III nitride quantum well layer by MOCVD.

[0079] Step 8: Prepare a transparent conductive layer on the p-type group III nitride material layer, such as... Figure 4 As shown in i.

[0080] The reaction pressure was set to 8.9 × 10⁻⁶. -6 Torr uses indium tin oxide as a target and prepares a transparent conductive layer of indium tin oxide on a p-type group III nitride material layer by magnetron sputtering.

[0081] Step nine: Fabricate a metal electrode layer on the transparent conductive layer and the n-type group III nitride material layer, such as... Figure 4 As shown in j.

[0082] First, etching is performed to a depth of 320 nm, followed by a reaction pressure of 8.9 × 10⁻⁶. -6 Torr uses titanium, aluminum, nickel, and gold as targets in sequence, and prepares titanium / aluminum / nickel / gold metal electrode layers on transparent conductive layers and n-type group III nitride material layers by magnetron sputtering.

[0083] Step 10: Anneal the prepared device at 800℃ for 10 minutes to obtain a high-power InGaN / GaN light-emitting diode with a boron nitride thickness of 1 nm based on a hemispherical diamond patterned substrate.

[0084] Implementation 2: Fabrication of a high-power InGaN / GaN light-emitting diode based on a tapered diamond patterned substrate with a boron nitride thickness of 2 nm.

[0085] Reference Figure 5 The implementation steps for this example are as follows:

[0086] Step 1: Perform photolithography and etching on the diamond substrate to generate a cone-shaped pattern, such as... Figure 5 a and Figure 5 As shown in b.

[0087] SF6 photoresist was coated onto the surface of a diamond substrate, and the spin coater was set to 4000 rpm to ensure the photoresist was evenly spread on the substrate surface. The diamond substrate with the uniformly coated photoresist was then placed on a hot plate at 180°C for hardening treatment. After hardening treatment, the substrate was placed in a photolithography machine to form a cone-shaped pattern on the photoresist. The diamond substrate with the photolithography completed was then placed in an etching machine to form a cone-shaped pattern on the diamond substrate through etching. Finally, the diamond substrate with the etching completed was placed in an organic solvent to remove the coated photoresist, completing the substrate patterning process and obtaining a diamond patterned substrate with a cone-shaped pattern on its surface.

[0088] Step 2: Prepare a boron nitride insertion layer on a diamond substrate, such as... Figure 5 As shown in c.

[0089] Boron nitride that has already grown on the surface of a metal catalyst is first transferred to the surface of polymethyl methacrylate (PMMA), and the boron nitride on the PMMA surface is then attached to the diamond substrate. Acetone is then used to dissolve the PMMA, causing the boron nitride to transfer and forming a 2 nm thick boron nitride insertion layer on the diamond substrate.

[0090] Step 3: Grow a nucleation layer of group III nitride material on the boron nitride insertion layer, such as... Figure 5 As shown in d.

[0091] With the reaction chamber temperature set at 1050℃, pressure at 380 Torr, and the introduced gases being ammonia and trimethylaluminum, a nitride material nucleation layer with a thickness of 50 nm was grown on a conical diamond substrate with a boron nitride nucleation layer using the MOCVD method.

[0092] Step 4: Grow a nitride material buffer layer on the nitride material nucleation layer, such as... Figure 5 As shown in e.

[0093] With the reaction chamber temperature set at 1300℃, the pressure at 40 Torr, and the introduced gases being ammonia and trimethylgallium, a 1000 nm thick nitride buffer layer was grown on the nitride nucleation layer using the MOCVD method.

[0094] Step 5: Grow an n-type group III nitride material layer on the nitride material buffer layer, such as... Figure 5 As shown in f.

[0095] With the reaction chamber temperature set at 1200℃ and the pressure at 80 Torr, and the introduced gases being ammonia, trimethylgallium, and silane, an n-type nitride material layer with a thickness of 2000 nm was grown on a nitride material buffer layer using the MOCVD method.

[0096] Step 6: Grow a group III nitride quantum well layer on the n-type group III nitride material layer, such as... Figure 5 As shown in g.

[0097] With the reaction chamber temperature set at 950℃, pressure at 35 Torr, and the introduced gases being ammonia, trimethylgallium, and trimethylindium, a group III nitride quantum well layer with a thickness of 18 nm was grown on an n-type nitride material layer using the MOCVD method.

[0098] Step 7: Grow a p-type group III nitride material layer on the group III nitride material quantum well layer, such as... Figure 5 As shown in h.

[0099] With the reaction chamber temperature set at 900℃, pressure at 40 Torr, and the introduced gases being ammonia, trimethylgallium, and magnesium thiocene, a 300 nm thick p-type GaN layer was grown on a group III nitride quantum well layer using the MOCVD method.

[0100] Step 8: Prepare a transparent conductive layer on the p-type group III nitride material layer, such as... Figure 5 As shown in i.

[0101] The reaction chamber pressure is set at 8.1 × 10⁻⁶. -6 Torr, with indium tin oxide as the target material, uses magnetron sputtering to prepare a transparent conductive layer of indium tin oxide on a p-type group III nitride material layer.

[0102] Step 9: Fabricate a metal electrode layer on the transparent conductive layer and the n-type group III nitride material layer, such as... Figure 5 As shown in j.

[0103] First, etching is performed to a depth of 350 nm. Then, the reaction chamber pressure is set to 8.1 × 10⁻⁶. -6 Torr, with target materials of titanium, aluminum, nickel and gold in sequence, uses magnetron sputtering to prepare titanium / aluminum / nickel / gold metal electrode layers on a transparent conductive layer and an n-type group III nitride material layer.

[0104] Step 10: Anneal the device at a temperature of 800℃ for 10 minutes to complete the fabrication of a high-power InGaN / GaN light-emitting diode with a boron nitride thickness of 2nm based on a tapered diamond patterned substrate.

[0105] Implementation 3: Fabrication of a high-power InGaN / GaN light-emitting diode based on a grooved diamond patterned substrate with a boron nitride thickness of 3 nm.

[0106] Reference Figure 6 The implementation steps for this example are as follows:

[0107] Step A involves photolithography and etching of the diamond substrate to create a groove-shaped pattern, such as... Figure 6 a and Figure 6 As shown in b.

[0108] A1) Coat the diamond substrate surface with SF6 photoresist and set the spin coater to 4000 rpm to make the photoresist spread evenly on the substrate surface.

[0109] A2) A diamond substrate uniformly coated with photoresist is placed on a hot plate at 180°C for hardening treatment, and the substrate after hardening treatment is placed in a photolithography machine to form a groove-shaped pattern on the photoresist.

[0110] A3) Place the photolithographically etched diamond substrate into an etching machine and form a groove-shaped pattern on the diamond substrate by etching;

[0111] A4) The etched diamond substrate is placed in an organic solvent to remove the coated photoresist, thus completing the substrate patterning process and obtaining a diamond patterned substrate with groove-shaped patterns on the surface.

[0112] Step B involves fabricating a boron nitride insertion layer on a diamond substrate, such as... Figure 6 As shown in c.

[0113] B1) Transferring boron nitride that has already grown on the surface of a metal catalyst to the surface of polymethyl methacrylate;

[0114] B2) Boron nitride on the surface of polymethyl methacrylate is bonded to the diamond substrate;

[0115] B3) Acetone was used to dissolve polymethyl methacrylate to achieve the transfer of boron nitride, resulting in a 3 nm thick boron nitride insertion layer on a diamond substrate.

[0116] Step C: Growing a nucleation layer of group III nitride material on the boron nitride insertion layer, such as... Figure 6 As shown in d.

[0117] A 15 nm thick nitride nucleation layer was grown on a grooved diamond substrate with a pre-transferred 3 nm thick boron nitride layer using MOCVD. The process conditions were: reaction chamber temperature of 900 °C, pressure of 360 Torr, and ammonia and trimethylaluminum as the introduced gases.

[0118] Step D: Growing a nitride material buffer layer on the nitride material nucleation layer, such as... Figure 6 As shown in e.

[0119] A nitride material buffer layer with a thickness of 3000 nm was grown on a nitride material nucleation layer using MOCVD process. The process conditions were: reaction chamber temperature of 1200℃, pressure of 30 Torr, and the introduced gases were ammonia and trimethylgallium.

[0120] Step E: Growing an n-type group III nitride material layer on the nitride material buffer layer, such as... Figure 6 As shown in f.

[0121] An 800 nm thick n-type nitride material layer was grown on a nitride material buffer layer using MOCVD. The process conditions were: reaction chamber temperature of 900 °C, pressure of 30 Torr, and the introduced gases were ammonia, trimethylgallium, and silane.

[0122] Step F involves growing a group III nitride quantum well layer on the n-type group III nitride material layer, such as... Figure 6 As shown in g.

[0123] A 180 nm thick group III nitride quantum well layer was grown on an n-type nitride material layer using MOCVD. The process conditions were: reaction chamber temperature of 900 °C, pressure of 30 Torr, and the introduced gases were ammonia, trimethylgallium, and trimethylindium.

[0124] Step G: Grow a p-type group III nitride material layer on the group III nitride material quantum well layer, such as... Figure 6 As shown in h.

[0125] A 100 nm thick p-type GaN layer was grown on a quantum well layer of group III nitride material using MOCVD. The process conditions were: reaction chamber temperature of 1000 °C, pressure of 50 Torr, and the introduced gases were ammonia, trimethylgallium, and magnesium pyrocene.

[0126] Step H involves preparing a transparent conductive layer on a p-type group III nitride material layer, such as... Figure 6 As shown in i.

[0127] Indium tin oxide transparent conductive layers were prepared on p-type group III nitride material layers by magnetron sputtering. The process conditions were: reaction pressure of 8.4 × 10⁻⁶. -6 Torr uses indium tin oxide as its sputtering target.

[0128] Step I: Fabricate a metal electrode layer on the transparent conductive layer and the n-type group III nitride material layer, such as... Figure 6 As shown in j.

[0129] First, etching is performed to a depth of 300 nm. Then, titanium / aluminum / nickel / gold metal electrode layers are sequentially fabricated on the transparent conductive layer and the n-type group III nitride material layer using magnetron sputtering to complete the device fabrication. The process conditions are: reaction pressure 8.4 × 10⁻⁶. -6 Torr uses sputtering targets of titanium, aluminum, nickel, and gold, in that order.

[0130] Step J involves annealing the device after the above steps in an annealing furnace at 800°C for 10 minutes to complete the fabrication process of a high-power InGaN / GaN light-emitting diode with a boron nitride thickness of 3 nm based on a grooved diamond patterned substrate.

[0131] The above description is merely a specific example of the present invention and does not constitute any limitation on the present invention. Obviously, those skilled in the art, after understanding the content and principles of the present invention, may make various modifications and changes in form and details without departing from the principles and structure of the present invention. However, these modifications and changes based on the ideas of the present invention are still within the scope of protection of the claims of the present invention.

Claims

1. A high-power nitride light-emitting diode based on a diamond-based patterned substrate, the structure of which, from bottom to top, consists of a diamond substrate layer (1), a boron nitride insertion layer (2), a nitride material nucleation layer (3), a nitride buffer layer (4), an n-type group III nitride material layer (5), wherein the upper left part of the n-type group III nitride material layer (5) consists of a group III nitride material quantum well layer (6), a p-type group III nitride material layer (7), a transparent conductive layer (8), and a metal electrode layer (9), and the upper right part is a metal electrode layer (9), characterized in that: The diamond substrate layer (1) has a patterned structure, which is used to improve the crystal quality of subsequent epitaxial materials and the light extraction efficiency of the device; The thickness of the boron nitride insertion layer (2) is 1-3 nm; A boron nitride insertion layer (2) is added between the nitride material nucleation layer (3) and the diamond substrate layer (1) to omit the bonding process in the device fabrication process.

2. The light-emitting diode according to claim 1, characterized in that, The diamond substrate (1) has a patterned structure, and its shape is any one of hemispherical, conical, or grooved.

3. The light-emitting diode according to claim 1, characterized in that: The thickness of the nitride material nucleation layer (3) is 10-50 nm; The thickness of the nitride material buffer layer (4) is 1000-3000 nm; The thickness of the n-type group III nitride material layer (5) is 500-2000 nm; The thickness of the p-type group III nitride material layer (7) is 50-300 nm.

4. The light-emitting diode according to claim 1, characterized in that: The group III nitride material quantum well layer (6) is an ordered structure composed of two group III nitride materials alternating, with a total thickness of 18-180 nm, enabling the emission of any specific wavelength from red light to ultraviolet light.

5. A method for fabricating a high-power nitride light-emitting diode based on a diamond-based patterned substrate, characterized in that, Includes the following steps: 1) Perform patterning preprocessing on the substrate layer; 2) Transfer a layer of boron nitride with a thickness of 1-3 nm onto the pretreated substrate; 3) A nitride nucleation layer of 10-50 nm was prepared on a diamond substrate with transferred boron nitride using MOCVD process; 4) A 1-3 μm nitride material buffer layer is grown on the nitride material nucleation layer using MOCVD process; 5) An n-type nitride material layer of 500-2000 nm was grown on the nitride material buffer layer using MOCVD process; 6) Grow 1-10 cycles of group III nitride material quantum well layers on an n-type nitride material layer using MOCVD process, wherein the thickness of the group III nitride material in each cycle is 18-180 nm; 7) A 50-300 nm p-type nitride material layer was grown on a group III nitride material quantum well layer using MOCVD process; 8) A transparent conductive layer is prepared on a p-type nitride material layer by magnetron sputtering; 9) Etch a portion of the device down to the n-type nitride material layer, and fabricate n-type electrodes on the n-type nitride material and p-type electrodes on the p-type nitride material using magnetron sputtering. 10) Anneal the prepared device.

6. The method according to claim 5, characterized in that, Step 1) involves patterning the substrate layer, as follows: 1a) Coat the diamond substrate (1) with photoresist and spread the photoresist evenly on its surface using a spin coater; 1b) The diamond substrate uniformly coated with photoresist in 1a) is placed on a high-temperature hot plate for hard film treatment; 1c) The substrate that has undergone hard film treatment is placed in a photolithography machine to form a pattern on the photoresist; 1d) The photolithographically etched diamond substrate is placed into an etching machine to form a pattern on the diamond substrate; 1e) Place the etched diamond substrate in an organic solvent to remove the coated photoresist and complete the substrate patterning preprocessing.

7. The method according to claim 5, characterized in that, The boron nitride transfer process in step 2) is implemented as follows: 2a) Transferring boron nitride already grown on the surface of a metal catalyst to the surface of an auxiliary organic material; 2b) The boron nitride on the surface of the auxiliary organic material is adhered to the diamond substrate; 2c) Use organic solvents to dissolve the auxiliary organic materials.

8. The method according to claim 5, characterized in that: The MOCVD process conditions in step 3) are: the reactants are trimethylaluminum and ammonia, the reaction temperature is 900-1200℃, and the reaction pressure is not less than 350 Torr. The MOCVD process conditions in step 4) are: the reactants are trimethylgallium and ammonia, the reaction temperature is 1200-1500℃, and the reaction pressure is 30-50 Torr. The MOCVD process conditions in step 5) are: the reactants are trimethylgallium, ammonia and silane, the reaction temperature is 900-1400 ℃, and the reaction pressure is 30-100 Torr. The MOCVD process conditions in step 6) are as follows: the reactants are trimethylgallium, trimethylindium and ammonia, the reaction temperature is 900-1000 ℃, and the reaction pressure is 30-40 Torr. The MOCVD process conditions in step 7) are as follows: the reactants are trimethylgallium, ammonia and magnesium pyrocene, the reaction temperature is 900-1000 ℃ and the reaction pressure is 30-50 Torr.

9. The method according to claim 5, characterized in that: The magnetron sputtering process conditions in step 8) are: reaction pressure below 9 × 10⁻⁶. -6 Torr, the target material is indium tin oxide; The magnetron sputtering process conditions in step 9) are: the reaction pressure is below 9 × 10⁻⁶. -6 Torr uses titanium, aluminum, nickel, and gold as its target materials, in that order.

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