CN111129240A - Epitaxial growth method for improving current expansion capability of nitride LED - Google Patents
Epitaxial growth method for improving current expansion capability of nitride LED Download PDFInfo
- Publication number
- CN111129240A CN111129240A CN201911410723.8A CN201911410723A CN111129240A CN 111129240 A CN111129240 A CN 111129240A CN 201911410723 A CN201911410723 A CN 201911410723A CN 111129240 A CN111129240 A CN 111129240A
- Authority
- CN
- China
- Prior art keywords
- layer
- growing
- gallium nitride
- sccm
- flow rate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/02—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
- H01L33/12—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies with a stress relaxation structure, e.g. buffer layer
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/005—Processes
- H01L33/0095—Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/02—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
- H01L33/14—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies with a carrier transport control structure, e.g. highly-doped semiconductor layer or current-blocking structure
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/02—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
- H01L33/20—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies with a particular shape, e.g. curved or truncated substrate
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/02—Semiconductor devices with at least one potential-jump barrier or surface barrier specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor bodies
- H01L33/26—Materials of the light emitting region
- H01L33/30—Materials of the light emitting region containing only elements of group III and group V of the periodic system
- H01L33/32—Materials of the light emitting region containing only elements of group III and group V of the periodic system containing nitrogen
Abstract
The invention provides an epitaxial growth method for improving the current spreading capability of a nitride LED, which comprises the process of growing a graphene layer, and specifically comprises the following steps: step 1, processing a substrate; step 2, growing a low-temperature nitride buffer layer on the substrate and forming irregular islands on the low-temperature nitride buffer layer, wherein the low-temperature nitride buffer layer comprises at least one of gallium nitride, aluminum nitride or aluminum gallium nitride; step 3, growing an undoped gallium nitride layer; step 4, growing a silicon-doped N-type gallium nitride layer containing a graphene layer; step 5, growing a luminous layer; step 6, growing a P-type aluminum gallium nitride layer doped with aluminum and magnesium and containing a graphene layer; step 7, growing a P-type gallium nitride layer doped with magnesium; and 8, preserving heat for 20-30 min at the temperature of 650-680 ℃, closing a heating system and a gas supply system, and cooling along with the furnace. The epitaxial growth method can effectively improve the current expansion condition of the light-emitting diode.
Description
Technical Field
The invention relates to the technical field of LEDs, in particular to an epitaxial growth method for improving the current expansion capability of a nitride LED.
Background
A Light-Emitting Diode (LED) is a semiconductor electronic device that converts electrical energy into optical energy. When the traditional LED works, the current distribution of the p layer and the n layer is not uniform, especially in the condition of high current density (35A/cm)2Above), the current edge effect is obvious, and the luminous efficiency is more likely to decline in the place where the current is concentrated, and the problems of breakdown short circuit and the like are more likely to occur, so that the luminous efficiency, the antistatic capability and the service life of the LED device are reduced. At present, many solutions have been proposed to solve the current spreading problem of nitride LEDs, such as adding AlGaN or InGaN insertion layers to the LED structure, however, the current spreading effect is not ideal enough, and further improvement of the current spreading performance of nitride LEDs is needed.
In summary, an epitaxial growth method for improving the current spreading capability of a nitride LED is urgently needed to solve the problems of low light emitting efficiency, easy breakdown short circuit and the like of the existing LED.
Disclosure of Invention
The invention aims to provide an epitaxial growth method for improving the current expansion capability of a nitride LED, which has the following specific technical scheme:
an epitaxial growth method for improving current spreading capability of a nitride LED comprises a process of growing a graphene layer, and specifically comprises the following steps:
step 2, growing a low-temperature nitride buffer layer on the substrate and forming irregular islands on the low-temperature nitride buffer layer, wherein the low-temperature nitride buffer layer comprises at least one of gallium nitride, aluminum nitride or aluminum gallium nitride;
step 3, growing an undoped gallium nitride layer;
step 4, growing a silicon-doped N-type gallium nitride layer containing a graphene layer;
step 5, growing a luminous layer;
step 6, growing a P-type aluminum gallium nitride layer doped with aluminum and magnesium and containing a graphene layer;
step 7, growing a P-type gallium nitride layer doped with magnesium;
and 8, preserving heat for 20-30 min at the temperature of 650-680 ℃, closing a heating system and a gas supply system, and cooling along with the furnace.
Preferably, the step 4 further comprises the following steps: step 4.1, growing a first N-type gallium nitride layer doped with silicon;
step 4.2, independently preparing a graphene layer;
4.3, covering PMMA on the surface of the graphene layer;
4.4, transferring the graphene layer to the first N-type gallium nitride layer;
and 4.5, continuously growing a second N-type gallium nitride layer doped with silicon on the graphene layer.
Preferably, in said step 4,
step 4.1, growing a first N-type gallium nitride layer doped with silicon, which specifically comprises the following steps: the pressure in the reaction chamber is 300 toGrowing a first N-type gallium nitride layer doped with silicon with the thickness of 0.1-2 mu m under the conditions of 600mbar, the temperature of 1000-1200 ℃, the flow of 30000-60000 sccm ammonia gas, 200-400 sccm trimethyl gallium, 100-130L/min hydrogen gas and 20-50 sccm silane, wherein the silicon doping concentration is 5 multiplied by 1018～1×1019atoms/cm3；
Step 4.2, independently preparing the graphene layer, specifically: the method comprises the steps of placing a copper foil in a quartz tube by adopting a chemical vapor deposition method and taking methane as a carbon source and a copper foil as a substrate, placing the quartz tube in a resistance furnace, sealing the quartz tube, heating to 930-1100 ℃ and keeping for 60-100 min, introducing argon gas with the flow rate of 150-200 mL/min and keeping for 10-30 min, carrying out high-temperature preheating treatment on the copper foil, introducing the methane with the flow rate of 10-20 mL/min, growing a graphene layer for 10-50 min, closing the methane after the reaction is finished, and moving the copper foil to a resistance furnace mouth to obtain the graphene layer grown on the copper foil, wherein the number of the graphene layer is 1-5;
step 4.3, covering PMMA (polymethyl methacrylate) on the surface of the graphene layer, specifically: firstly, flatly fixing a copper foil with a graphene layer growing on a wafer, secondly, putting the wafer into a spin coater, controlling the rotating speed to be 4000-5000 r/min, uniformly coating a PMMA adhesive layer on the surface of the graphene layer, then taking out the wafer, baking the wafer for 10-15 min at the temperature of 100-120 ℃, putting the copper foil after being uniformly coated into a ferric trichloride solution with the mass fraction of 15-40%, soaking for 4-5 h, and rinsing for at least 3 times by deionized water to obtain the graphene layer with the surface covered with PMMA;
step 4.4, transferring the graphene layer to the first N-type gallium nitride layer, specifically: transferring the graphene layer with the PMMA-coated surface onto a first N-type gallium nitride layer, naturally drying, immersing in an acetone solution for 15-20 min to remove a PMMA glue layer, finally immersing in an ethanol solution for 5-10 min, taking out, and drying in the air to obtain the graphene layer growing on the first N-type gallium nitride layer;
and 4.5, continuously growing a second N-type gallium nitride layer doped with silicon on the graphene layer, specifically: the pressure of the reaction cavity is 300-600 mbar, the temperature is 1000-1200 ℃, and the inlet flow is 30000-600Growing a second N-type gallium nitride layer doped with silicon with the thickness of 1-3 mu m on the graphene layer in the step 4.4 under the conditions of ammonia gas of 00sccm, trimethyl gallium of 200-400 sccm, hydrogen of 100-130L/min and silane of 20-50 sccm, wherein the silicon doping concentration is 5 multiplied by 1018～1×1019atoms/cm3。
Preferably, the step 6 further comprises the following steps:
step 6.1, growing the P-type aluminum gallium nitride layer doped with aluminum and magnesium, which comprises the following specific steps: growing a P-type aluminum gallium nitride layer doped with aluminum and magnesium with the thickness of 50-100 nm under the conditions that the pressure of a reaction cavity is 200-400 mbar, the temperature is 900-950 ℃, the flow rate is 50000-70000 sccm of ammonia gas, 30-60 sccm of trimethyl gallium, 100-130L/min of hydrogen gas, 100-130 sccm of trimethyl aluminum and 1000-1800 sccm of magnesium dicalloxide are introduced, and the aluminum doping concentration is 1 multiplied by 1020～3×1020atoms/cm3Doping concentration of magnesium 1X 1019～1×1020atoms/cm3；
Step 6.2, growing a graphene layer on the P-type aluminum gallium nitride layer, specifically: and (4) obtaining the graphene layer with the surface covered with PMMA by adopting the methods in the steps 4.2 and 4.3, transferring the graphene layer with the surface covered with PMMA onto the P-type aluminum gallium nitride layer, naturally drying, immersing in an acetone solution for 15-20 min to remove the PMMA glue layer, finally immersing in an ethanol solution for 5-10 min, taking out, and drying in the air to obtain the graphene layer growing on the P-type aluminum gallium nitride layer.
Preferably, the step 1 specifically comprises: and treating the substrate for 8-10 min under the conditions that the pressure of the reaction cavity is 100-300 mbar, the temperature is 1000-1100 ℃ and hydrogen with the flow rate of 100-130L/min is introduced.
Preferably, the step 2 specifically comprises: growing low-temperature nitride buffer layer gallium nitride with the thickness of 20-40 nm on the substrate under the conditions that the pressure of a reaction cavity is 300-600 mbar, the temperature is 500-600 ℃, ammonia gas with the flow rate of 10000-20000 sccm, trimethyl gallium with the flow rate of 50-100 sccm and hydrogen gas with the flow rate of 100-130L/min are introduced;
and keeping the temperature for 300-500 s under the conditions that the pressure of the reaction cavity is 300-600 mbar, the temperature is 1000-1100 ℃, and ammonia gas with the flow rate of 30000-40000 sccm and hydrogen gas with the flow rate of 100-130L/min are introduced, so that irregular islands are formed on the gallium nitride buffer layer at the low temperature.
Preferably, the step 3 specifically comprises: growing a non-doped gallium nitride layer with the thickness of 2-4 mu m under the conditions that the pressure of a reaction cavity is 300-600 mbar, the temperature is 1000-1200 ℃, ammonia gas with the flow rate of 30000-40000 sccm, trimethyl gallium with the flow rate of 200-400 sccm and hydrogen gas with the flow rate of 100-130L/min are introduced.
Preferably, the step 5 specifically comprises: growing indium-doped In with a thickness of 2.5-3.5 nm under the conditions that the pressure of a reaction cavity is 300-400 mbar, the temperature is 700-750 ℃, ammonia gas with a flow rate of 50000-70000 sccm, trimethyl gallium with a flow rate of 20-40 sccm, trimethyl indium with a flow rate of 1500-2000 sccm and nitrogen gas with a flow rate of 100-130L/min are introducedxGa(1-x)An N layer, wherein x is 0.20-0.25, and the light-emitting wavelength is 450-455 nm; then raising the temperature to 750-850 ℃, keeping the pressure of the reaction cavity unchanged, introducing ammonia gas with the flow rate of 50000-70000 sccm, trimethyl gallium with the flow rate of 20-100 sccm and nitrogen gas with the flow rate of 100-130L/min, and growing a gallium nitride layer with the thickness of 8-15 nm; repeatedly and alternately growing InxGa(1-x)N layer and gallium nitride layer, the number of alternating cycle is controlled 7 ~ 15.
Preferably, the step 7 specifically comprises: growing a magnesium-doped P-type gallium nitride layer under the conditions that the pressure of a reaction cavity is 400-900 mbar, the temperature is 950-1000 ℃, 50000-70000 sccm of ammonia gas, 20-100 sccm of trimethyl gallium, 100-130L/min of hydrogen and 1000-3000 sccm of magnesium dicumyl are introduced, wherein the magnesium doping concentration is 1 multiplied by 1019～1×1020atoms/cm3。
Preferably, the substrate comprises at least one of sapphire, silicon carbide, silicon, gallium arsenide, zinc oxide, or lithium aluminate.
The technical scheme of the invention has the following beneficial effects:
according to the epitaxial growth method, the graphene layer grows on the N-type gallium nitride layer doped with silicon in the step 4 and the graphene layer grows on the P-type aluminum gallium nitride layer in the step 6, so that the current of the light-emitting diode can be effectively improvedThe condition is expanded, and the optical, electric and thermal properties of the LED device are improved. Graphene (Graphene) is a polymer made of carbon atoms in sp2The hybrid tracks form a hexagonal honeycomb-lattice two-dimensional carbon nanomaterial, the electron mobility of graphene is less influenced by temperature change, and when the temperature is 50-500K, the electron mobility of single-layer graphene is 15000cm2V.s, and the graphene has super-strong conductivity in the molecular layer, and simultaneously, carbon atoms between molecules in the graphene plane pass through sp2The hybrid rail forms a hexagonal structure, the performance is stable, the hybrid rail is similar to the (0001) surface of wurtzite gallium nitride, nitride epitaxy can be performed on a graphene layer, when the number of graphene layers is 1-5, the influence on the nitride epitaxy is small, and the epitaxial crystallization quality can be ensured; in addition, in the nitride LED epitaxy process, 1-5 layers of graphene are inserted on the aluminum gallium nitride layer, the longitudinal resistance of the device is improved by the aluminum gallium nitride high-resistance layer, the transverse resistance is reduced by the graphene layer, the current distribution uniformity of the device is further improved, the graphene has excellent thermal conductivity, and the heat dissipation capability of the device is improved, so that the optical, electrical and thermal properties of the LED device are improved.
In addition to the objects, features and advantages described above, other objects, features and advantages of the present invention are also provided. The present invention will be described in further detail below with reference to examples.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:
fig. 1 is a schematic view of an epitaxial structure of an LED according to preferred embodiment 1 of the present invention;
the light emitting diode comprises a substrate 1, a substrate 2, a low-temperature nitride buffer layer 3, a non-doped gallium nitride layer 4, a first N-type gallium nitride layer doped with silicon 5, a graphene layer grown on the first N-type gallium nitride layer 6, a second N-type gallium nitride layer doped with silicon 7, a light emitting layer 8, a P-type aluminum gallium nitride layer 9, a graphene layer grown on the P-type aluminum gallium nitride layer 10 and a P-type gallium nitride layer.
Detailed Description
The following is a detailed description of embodiments of the invention, but the invention can be implemented in many different ways, as defined and covered by the claims.
Example 1:
an epitaxial growth method for improving current spreading capability of a nitride LED comprises a process of growing a graphene layer, and specifically comprises the following steps:
step 2, growing a low-temperature nitride buffer layer 2 on the substrate 1 and forming irregular islands on the low-temperature nitride buffer layer 2, wherein the low-temperature nitride buffer layer 2 comprises at least one of gallium nitride, aluminum nitride or aluminum gallium nitride;
step 3, growing a non-doped gallium nitride layer 3;
step 4, growing a silicon-doped N-type gallium nitride layer containing a graphene layer;
step 5, growing a luminescent layer 7;
step 6, growing a P-type aluminum gallium nitride layer 8 which contains graphene layers and is doped with aluminum and magnesium;
step 7, growing a P-type gallium nitride layer 10 doped with magnesium;
and 8, preserving heat for 20-30 min at the temperature of 650-680 ℃, closing a heating system and a gas supply system, and cooling along with the furnace.
The step 4 further comprises the following steps:
step 4.1, growing a first N-type gallium nitride layer 4 doped with silicon, which specifically comprises the following steps: growing a first N-type gallium nitride layer 4 doped with silicon with the thickness of 0.1-2 mu m under the conditions that the pressure of a reaction cavity is 300-600 mbar, the temperature is 1000-1200 ℃, ammonia gas with the flow rate of 30000-60000 sccm, trimethyl gallium with the flow rate of 200-400 sccm, hydrogen gas with the flow rate of 100-130L/min and silane with the flow rate of 20-50 sccm are introduced, and the silicon doping concentration is 5 multiplied by 1018～1×1019atoms/cm3；
Step 4.2, independently preparing the graphene layer, specifically: the method comprises the following steps of adopting a chemical vapor deposition method, taking methane as a carbon source, taking a copper foil as a substrate, placing the copper foil in a quartz tube, placing the quartz tube in a resistance furnace, sealing the quartz tube, heating to 930-1100 ℃ and keeping for 60-100 min, introducing argon gas with the flow of 150-200 mL/min and keeping for 10-30 min, carrying out high-temperature preheating treatment on the copper foil, introducing methane with the flow of 10-20 mL/min, growing a graphene layer for 10-50 min, closing the methane after the reaction is finished, moving the copper foil to a resistance furnace mouth, obtaining the graphene layer grown on the copper foil, wherein the number of the graphene layer is 1, the copper foil mainly plays a role similar to a catalyst, carbon atoms are adsorbed on the surface of the copper foil and crystallized to generate the graphene layer, and the copper foil needs to be pretreated, specifically: sequentially immersing the copper foil into dilute hydrochloric acid with the mass fraction of 18% and ethanol for ultrasonic cleaning, then washing the copper foil with deionized water, and finally drying the copper foil;
4.3, covering PMMA on the surface of the graphene layer, specifically: firstly, flatly fixing a copper foil on which a graphene layer grows on a wafer, secondly, putting the wafer into a glue homogenizing machine, controlling the rotating speed to be 4000-5000 r/min, uniformly coating a PMMA glue layer on the surface of the graphene layer, then taking out the wafer, baking the wafer for 10-15 min at the temperature of 100-120 ℃, putting the copper foil after glue homogenizing into a ferric trichloride solution with the mass fraction of 15-40%, soaking for 4-5 h, rinsing for at least 3 times by deionized water (ensuring that the residual ferric trichloride solution is thoroughly cleaned), and obtaining the graphene layer with the surface covered with PMMA;
step 4.4, transferring the graphene layer to the first N-type gallium nitride layer, specifically: transferring the graphene layer with the PMMA-coated surface onto a first N-type gallium nitride layer, naturally drying, immersing in an acetone solution for 15-20 min to remove a PMMA glue layer, finally immersing in an ethanol solution for 5-10 min, taking out, and drying in the air to obtain a graphene layer 5 growing on the first N-type gallium nitride layer;
and 4.5, continuously growing a second N-type gallium nitride layer 6 doped with silicon on the graphene layer, specifically: growing a second N-type gallium nitride layer 6 doped with silicon with the thickness of 1-3 mu m on the graphene layer in the step 4.4 under the conditions that the pressure of the reaction cavity is 300-600 mbar, the temperature is 1000-1200 ℃, the flow of ammonia gas is 30000-60000 sccm, trimethyl gallium is 200-400 sccm, hydrogen gas is 100-130L/min and silane is 20-50 sccm are introduced, and the silicon doping concentration is 5 multiplied by 1018～1×1019atoms/cm3。
The step 6 further comprises the following steps:
step 6.1, growing the P-type aluminum gallium nitride layer 8 doped with aluminum and magnesium, which comprises the following specific steps: growing a P-type aluminum gallium nitride layer 8 doped with aluminum and magnesium with the thickness of 50-100 nm under the conditions that the pressure of a reaction cavity is 200-400 mbar, the temperature is 900-950 ℃, the flow rate of ammonia gas of 50000-70000 sccm, 30-60 sccm trimethyl gallium, 100-130L/min hydrogen, 100-130 sccm trimethyl aluminum and 1000-1800 sccm magnesium are introduced, and the aluminum doping concentration is 1 multiplied by 1020～3×1020atoms/cm3Doping concentration of magnesium 1X 1019～1×1020atoms/cm3；
Step 6.2, growing a graphene layer on the P-type aluminum gallium nitride layer 8, specifically: and (3) obtaining the graphene layer with the surface covered with PMMA by adopting the methods in the steps 4.2 and 4.3, transferring the graphene layer with the surface covered with PMMA onto the P-type aluminum gallium nitride layer 8 for natural air drying, then immersing the graphene layer into an acetone solution for 15-20 min to remove the PMMA glue layer, finally immersing the graphene layer into an ethanol solution for 5-10 min, taking out and drying the graphene layer to obtain the graphene layer 9 growing on the P-type aluminum gallium nitride layer, wherein the number of the graphene layer is 1.
The step 1 specifically comprises the following steps: and treating the substrate for 8-10 min under the conditions that the pressure of the reaction cavity is 100-300 mbar, the temperature is 1000-1100 ℃ and hydrogen with the flow rate of 100-130L/min is introduced.
The step 2 specifically comprises the following steps: growing a low-temperature nitride buffer layer 2 gallium nitride with the thickness of 20-40 nm on the substrate 1 under the conditions that the pressure of a reaction cavity is 300-600 mbar, the temperature is 500-600 ℃, and ammonia gas with the flow rate of 10000-20000 sccm, trimethyl gallium with the flow rate of 50-100 sccm and hydrogen gas with the flow rate of 100-130L/min are introduced;
and keeping the temperature for 300-500 s under the conditions that the pressure of the reaction cavity is 300-600 mbar, the temperature is 1000-1100 ℃, and ammonia gas with the flow rate of 30000-40000 sccm and hydrogen gas with the flow rate of 100-130L/min are introduced, so that irregular islands are formed on the gallium nitride of the low-temperature nitride buffer layer 2.
The step 3 specifically comprises the following steps: growing the non-doped gallium nitride layer 3 with the thickness of 2-4 mu m under the conditions that the pressure of the reaction cavity is 300-600 mbar, the temperature is 1000-1200 ℃, ammonia gas with the flow rate of 30000-40000 sccm, trimethyl gallium with the flow rate of 200-400 sccm and hydrogen gas with the flow rate of 100-130L/min are introduced.
The step 5 specifically comprises the following steps: growing indium-doped In with a thickness of 2.5-3.5 nm under the conditions that the pressure of a reaction cavity is 300-400 mbar, the temperature is 700-750 ℃, ammonia gas with a flow rate of 50000-70000 sccm, trimethyl gallium with a flow rate of 20-40 sccm, trimethyl indium with a flow rate of 1500-2000 sccm and nitrogen gas with a flow rate of 100-130L/min are introducedxGa(1-x)An N layer, wherein x is 0.20-0.25, and the light-emitting wavelength is 450-455 nm; then raising the temperature to 750-850 ℃, keeping the pressure of the reaction cavity unchanged, introducing ammonia gas with the flow rate of 50000-70000 sccm, trimethyl gallium with the flow rate of 20-100 sccm and nitrogen gas with the flow rate of 100-130L/min, and growing a gallium nitride layer with the thickness of 8-15 nm; repeatedly and alternately growing InxGa(1-x)N layer and gallium nitride layer, the number of alternating periods is controlled to be 10.
The step 7 is specifically: growing a magnesium-doped P-type gallium nitride layer 10 under the conditions that the pressure of a reaction cavity is 400-900 mbar, the temperature is 950-1000 ℃, 50000-70000 sccm of ammonia gas, 20-100 sccm of trimethyl gallium, 100-130L/min of hydrogen and 1000-3000 sccm of magnesium dicumyl are introduced, wherein the magnesium doping concentration is 1 multiplied by 1019～1×1020atoms/cm3。
The substrate 1 is sapphire.
The LED epitaxial structure prepared by the epitaxial growth method is shown in figure 1.
Comparative example 1
The difference from example 1 is that the number of graphene layers in step 4 and step 6 is 0, and other conditions are not changed.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. An epitaxial growth method for improving current spreading capability of a nitride LED is characterized by comprising a process of growing a graphene layer, and specifically comprises the following steps:
step 1, processing a substrate;
step 2, growing a low-temperature nitride buffer layer on the substrate and forming irregular islands on the low-temperature nitride buffer layer, wherein the low-temperature nitride buffer layer comprises at least one of gallium nitride, aluminum nitride or aluminum gallium nitride;
step 3, growing an undoped gallium nitride layer;
step 4, growing a silicon-doped N-type gallium nitride layer containing a graphene layer;
step 5, growing a luminous layer;
step 6, growing a P-type aluminum gallium nitride layer doped with aluminum and magnesium and containing a graphene layer;
step 7, growing a P-type gallium nitride layer doped with magnesium;
and 8, preserving heat for 20-30 min at the temperature of 650-680 ℃, closing a heating system and a gas supply system, and cooling along with the furnace.
2. Epitaxial growth method according to claim 1, characterized in that said step 4 comprises the following steps:
step 4.1, growing a first N-type gallium nitride layer doped with silicon;
step 4.2, independently preparing a graphene layer;
4.3, covering PMMA on the surface of the graphene layer;
4.4, transferring the graphene layer to the first N-type gallium nitride layer;
and 4.5, continuously growing a second N-type gallium nitride layer doped with silicon on the graphene layer.
3. Epitaxial growth method according to claim 2, characterized in that, in step 4,
step 4.1, growing a first N-type gallium nitride layer doped with silicon, which specifically comprises the following steps: growing a first N-type gallium nitride layer doped with silicon with the thickness of 0.1-2 mu m under the conditions that the pressure of a reaction cavity is 300-600 mbar, the temperature is 1000-1200 ℃, ammonia gas with the flow rate of 30000-60000 sccm, trimethyl gallium with the flow rate of 200-400 sccm, hydrogen gas with the flow rate of 100-130L/min and silane with the flow rate of 20-50 sccm are introduced, and the silicon doping concentration is 5 multiplied by 1018～1×1019atoms/cm3；
Step 4.2, independently preparing the graphene layer, specifically: the method comprises the steps of placing a copper foil in a quartz tube by adopting a chemical vapor deposition method and taking methane as a carbon source and a copper foil as a substrate, placing the quartz tube in a resistance furnace, sealing the quartz tube, heating to 930-1100 ℃ and keeping for 60-100 min, introducing argon gas with the flow rate of 150-200 mL/min and keeping for 10-30 min, carrying out high-temperature preheating treatment on the copper foil, introducing the methane with the flow rate of 10-20 mL/min, growing a graphene layer for 10-50 min, closing the methane after the reaction is finished, and moving the copper foil to a resistance furnace mouth to obtain the graphene layer grown on the copper foil, wherein the number of the graphene layer is 1-5;
4.3, covering PMMA on the surface of the graphene layer, specifically: firstly, flatly fixing a copper foil with a graphene layer growing on a wafer, secondly, putting the wafer into a spin coater, controlling the rotating speed to be 4000-5000 r/min, uniformly coating a PMMA adhesive layer on the surface of the graphene layer, then taking out the wafer, baking the wafer for 10-15 min at the temperature of 100-120 ℃, putting the copper foil after being uniformly coated into a ferric trichloride solution with the mass fraction of 15-40%, soaking for 4-5 h, and rinsing for at least 3 times by deionized water to obtain the graphene layer with the surface covered with PMMA;
step 4.4, transferring the graphene layer to the first N-type gallium nitride layer, specifically: transferring the graphene layer with the PMMA-coated surface onto a first N-type gallium nitride layer, naturally drying, immersing in an acetone solution for 15-20 min to remove a PMMA glue layer, finally immersing in an ethanol solution for 5-10 min, taking out, and drying in the air to obtain the graphene layer growing on the first N-type gallium nitride layer;
and 4.5, continuously growing a second N-type gallium nitride layer doped with silicon on the graphene layer, specifically: growing a second N-type gallium nitride layer doped with silicon with the thickness of 1-3 mu m on the graphene layer in the step 4.4 under the conditions that the pressure of the reaction cavity is 300-600 mbar, the temperature is 1000-1200 ℃, the flow of ammonia gas is 30000-60000 sccm, trimethyl gallium is 200-400 sccm, hydrogen gas is 100-130L/min and silane is 20-50 sccm are introduced, and the silicon doping concentration is 5 multiplied by 1018～1×1019atoms/cm3。
4. Epitaxial growth method according to claim 3, characterized in that said step 6 comprises the following steps:
step 6.1, growing the P-type aluminum gallium nitride layer doped with aluminum and magnesium, which comprises the following specific steps: growing a P-type aluminum gallium nitride layer doped with aluminum and magnesium with the thickness of 50-100 nm under the conditions that the pressure of a reaction cavity is 200-400 mbar, the temperature is 900-950 ℃, the flow rate is 50000-70000 sccm of ammonia gas, 30-60 sccm of trimethyl gallium, 100-130L/min of hydrogen gas, 100-130 sccm of trimethyl aluminum and 1000-1800 sccm of magnesium dicalloxide are introduced, and the aluminum doping concentration is 1 multiplied by 1020～3×1020atoms/cm3Doping concentration of magnesium 1X 1019～1×1020atoms/cm3；
Step 6.2, growing a graphene layer on the P-type aluminum gallium nitride layer, specifically: and (4) obtaining the graphene layer with the surface covered with PMMA by adopting the methods in the steps 4.2 and 4.3, transferring the graphene layer with the surface covered with PMMA onto the P-type aluminum gallium nitride layer, naturally drying, immersing in an acetone solution for 15-20 min to remove the PMMA glue layer, finally immersing in an ethanol solution for 5-10 min, taking out, and drying in the air to obtain the graphene layer growing on the P-type aluminum gallium nitride layer.
5. Epitaxial growth method according to claim 4, characterized in that said step 1 is in particular: and treating the substrate for 8-10 min under the conditions that the pressure of the reaction cavity is 100-300 mbar, the temperature is 1000-1100 ℃ and hydrogen with the flow rate of 100-130L/min is introduced.
6. Epitaxial growth method according to claim 5, characterized in that said step 2 is in particular: growing low-temperature nitride buffer layer gallium nitride with the thickness of 20-40 nm on the substrate under the conditions that the pressure of a reaction cavity is 300-600 mbar, the temperature is 500-600 ℃, ammonia gas with the flow rate of 10000-20000 sccm, trimethyl gallium with the flow rate of 50-100 sccm and hydrogen gas with the flow rate of 100-130L/min are introduced;
and keeping the temperature for 300-500 s under the conditions that the pressure of the reaction cavity is 300-600 mbar, the temperature is 1000-1100 ℃, and ammonia gas with the flow rate of 30000-40000 sccm and hydrogen gas with the flow rate of 100-130L/min are introduced, so that irregular islands are formed on the gallium nitride buffer layer at the low temperature.
7. Epitaxial growth method according to claim 6, characterized in that said step 3 is in particular: growing a non-doped gallium nitride layer with the thickness of 2-4 mu m under the conditions that the pressure of a reaction cavity is 300-600 mbar, the temperature is 1000-1200 ℃, ammonia gas with the flow rate of 30000-40000 sccm, trimethyl gallium with the flow rate of 200-400 sccm and hydrogen gas with the flow rate of 100-130L/min are introduced.
8. Epitaxial growth method according to claim 7, characterized in that said step 5 is in particular: growing indium-doped In with a thickness of 2.5-3.5 nm under the conditions that the pressure of a reaction cavity is 300-400 mbar, the temperature is 700-750 ℃, ammonia gas with a flow rate of 50000-70000 sccm, trimethyl gallium with a flow rate of 20-40 sccm, trimethyl indium with a flow rate of 1500-2000 sccm and nitrogen gas with a flow rate of 100-130L/min are introducedxGa(1-x)An N layer, wherein x is 0.20-0.25, and the light-emitting wavelength is 450-455 nm; then raising the temperature to 750-850 ℃, keeping the pressure of the reaction cavity unchanged, and introducingIntroducing ammonia gas with the flow rate of 50000-70000 sccm, trimethyl gallium with the flow rate of 20-100 sccm and nitrogen gas with the flow rate of 100-130L/min, and growing a gallium nitride layer with the thickness of 8-15 nm; repeatedly and alternately growing InxGa(1-x)N layer and gallium nitride layer, the number of alternating cycle is controlled 7 ~ 15.
9. Epitaxial growth method according to claim 8, characterized in that said step 7 is in particular: growing a magnesium-doped P-type gallium nitride layer under the conditions that the pressure of a reaction cavity is 400-900 mbar, the temperature is 950-1000 ℃, 50000-70000 sccm of ammonia gas, 20-100 sccm of trimethyl gallium, 100-130L/min of hydrogen and 1000-3000 sccm of magnesium dicumyl are introduced, wherein the magnesium doping concentration is 1 multiplied by 1019～1×1020atoms/cm3。
10. Epitaxial growth method according to one of the claims 1-9, characterized in that the substrate comprises at least one of sapphire, silicon carbide, silicon, gallium arsenide, zinc oxide or lithium aluminate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911410723.8A CN111129240A (en) | 2019-12-31 | 2019-12-31 | Epitaxial growth method for improving current expansion capability of nitride LED |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911410723.8A CN111129240A (en) | 2019-12-31 | 2019-12-31 | Epitaxial growth method for improving current expansion capability of nitride LED |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111129240A true CN111129240A (en) | 2020-05-08 |
Family
ID=70506367
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911410723.8A Pending CN111129240A (en) | 2019-12-31 | 2019-12-31 | Epitaxial growth method for improving current expansion capability of nitride LED |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111129240A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111613698A (en) * | 2020-05-22 | 2020-09-01 | 青岛粲耀新材料科技有限责任公司 | Graphene intercalation III-group nitride semiconductor composite film and preparation method thereof |
| CN111816741A (en) * | 2020-07-07 | 2020-10-23 | 中国科学院长春光学精密机械与物理研究所 | GaN-based monolithic integrated white light LED based on Van der Waals epitaxy and preparation method thereof |
| CN112186083A (en) * | 2020-09-28 | 2021-01-05 | 华灿光电(苏州）有限公司 | Light emitting diode epitaxial wafer and preparation method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150041762A1 (en) * | 2010-09-21 | 2015-02-12 | The Government Of The United States Of America, As Represented By The Secretary Of The Navy | Transistor Having Graphene Base |
| CN106340575A (en) * | 2016-11-22 | 2017-01-18 | 芜湖德豪润达光电科技有限公司 | Gallium-nitride-based photoelectric device epitaxial structure having graphene layer and preparation method thereof |
| CN106876529A (en) * | 2017-01-12 | 2017-06-20 | 华灿光电（浙江）有限公司 | A kind of epitaxial wafer of gallium nitride based light emitting diode and preparation method thereof |
| CN108807627A (en) * | 2018-04-24 | 2018-11-13 | 河源市众拓光电科技有限公司 | A kind of high-power vertical structure LED epitaxial structure and preparation method thereof |
| CN109411579A (en) * | 2018-01-06 | 2019-03-01 | 李丹丹 | Semiconductor devices and preparation method thereof with graphene-structured |
-
2019
- 2019-12-31 CN CN201911410723.8A patent/CN111129240A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20150041762A1 (en) * | 2010-09-21 | 2015-02-12 | The Government Of The United States Of America, As Represented By The Secretary Of The Navy | Transistor Having Graphene Base |
| CN106340575A (en) * | 2016-11-22 | 2017-01-18 | 芜湖德豪润达光电科技有限公司 | Gallium-nitride-based photoelectric device epitaxial structure having graphene layer and preparation method thereof |
| CN106876529A (en) * | 2017-01-12 | 2017-06-20 | 华灿光电（浙江）有限公司 | A kind of epitaxial wafer of gallium nitride based light emitting diode and preparation method thereof |
| CN109411579A (en) * | 2018-01-06 | 2019-03-01 | 李丹丹 | Semiconductor devices and preparation method thereof with graphene-structured |
| CN108807627A (en) * | 2018-04-24 | 2018-11-13 | 河源市众拓光电科技有限公司 | A kind of high-power vertical structure LED epitaxial structure and preparation method thereof |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111613698A (en) * | 2020-05-22 | 2020-09-01 | 青岛粲耀新材料科技有限责任公司 | Graphene intercalation III-group nitride semiconductor composite film and preparation method thereof |
| CN111613698B (en) * | 2020-05-22 | 2020-12-01 | 山西穿越光电科技有限责任公司 | Graphene intercalation III-group nitride semiconductor composite film and preparation method thereof |
| CN111816741A (en) * | 2020-07-07 | 2020-10-23 | 中国科学院长春光学精密机械与物理研究所 | GaN-based monolithic integrated white light LED based on Van der Waals epitaxy and preparation method thereof |
| CN111816741B (en) * | 2020-07-07 | 2021-05-18 | 中国科学院长春光学精密机械与物理研究所 | GaN-based monolithic integrated white light LED based on Van der Waals epitaxy and preparation method thereof |
| CN112186083A (en) * | 2020-09-28 | 2021-01-05 | 华灿光电(苏州）有限公司 | Light emitting diode epitaxial wafer and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111129240A (en) | Epitaxial growth method for improving current expansion capability of nitride LED | |
| Sun et al. | Recent Advances on III‐Nitride nanowire light emitters on foreign substrates–toward flexible photonics | |
| WO2010111854A1 (en) | Uv led and method for fabricating the same | |
| WO2022127093A1 (en) | V-shaped tunneling junction led epitaxial structure based on h-bn and preparation method therefor | |
| CN107293622B (en) | Epitaxial wafer of light emitting diode and preparation method thereof | |
| CN106783948A (en) | Growth InN nano-pillar epitaxial wafers on a si substrate and preparation method thereof | |
| CN108899401B (en) | Preparation method of GaN-based LED device based on graphene insertion layer structure | |
| US9269856B2 (en) | Method for making light emitting diode | |
| CN106328780B (en) | The method of light emitting diode substrate epitaxial growth based on AlN templates | |
| US9698350B2 (en) | Light emitting diode | |
| CN110055589B (en) | Large-size single-layer hexagonal boron nitride single crystal or film and preparation method thereof | |
| CN110993752A (en) | LED epitaxial growth method taking graphene as buffer layer | |
| CN103337571A (en) | Epitaxial structure for improving wavelength concentration in GaN-based epitaxial wafer and growth method of epitaxial structure | |
| CN206271710U (en) | Growth InN nano-pillar epitaxial wafers on a si substrate | |
| CN108493304A (en) | A kind of preparation method of LED epitaxial slice | |
| KR100870837B1 (en) | Moisture removal method of thin film zinc oxide | |
| CN102487113B (en) | GaN-based light-emitting diode (LED) epitaxial wafer capable of improving luminous efficiency, and preparation method and application thereof | |
| CN109166951B (en) | Application of graphene nano-patterned sapphire substrate in ultraviolet LED technology | |
| CN107706278B (en) | Preparation method and application of transparent electrode of ultraviolet light-emitting diode | |
| CN106784195B (en) | A kind of epitaxial growth method improving light emitting diode quality | |
| CN111261755B (en) | LED epitaxial growth method | |
| JPH11310776A (en) | Luminescent material, production thereof, and luminescent element prepared by using the same | |
| CN109449268B (en) | LED epitaxial structure for reducing resistivity of P-type GaN layer and growth method thereof | |
| CN208848921U (en) | The GaN base nano-pillar LED epitaxial wafer being grown in silicon/graphene compound substrate | |
| CN112687770B (en) | LED epitaxial growth method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200508 |