CN111769180A - LED epitaxial growth method suitable for small-spacing display screen - Google Patents

LED epitaxial growth method suitable for small-spacing display screen Download PDF

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CN111769180A
CN111769180A CN202010662051.6A CN202010662051A CN111769180A CN 111769180 A CN111769180 A CN 111769180A CN 202010662051 A CN202010662051 A CN 202010662051A CN 111769180 A CN111769180 A CN 111769180A
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CN111769180B (en
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徐平
王杰
谢鹏杰
周佐华
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Xiangneng Hualei Optoelectrical Co Ltd
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Xiangneng Hualei Optoelectrical Co Ltd
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    • 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
    • H01L33/0062—Processes for devices with an active region comprising only III-V compounds
    • H01L33/0066—Processes for devices with an active region comprising only III-V compounds with a substrate not being a III-V compound
    • H01L33/007—Processes for devices with an active region comprising only III-V compounds with a substrate not being a III-V compound comprising nitride compounds
    • 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
    • H01L33/04—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 quantum effect structure or superlattice, e.g. tunnel junction
    • H01L33/06—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 quantum effect structure or superlattice, e.g. tunnel junction within the light emitting region, e.g. quantum confinement structure or tunnel barrier
    • 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
    • H01L33/145—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 with a 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
    • H01L33/26—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
    • H01L33/325—Materials of the light emitting region containing only elements of group III and group V of the periodic system containing nitrogen characterised by the doping materials

Abstract

The application discloses a light-emitting diode (LED) epitaxial growth method suitable for a small-spacing display screen, which sequentially comprises the following steps of: treating a substrate, growing a low-temperature buffer layer GaN, growing an undoped GaN layer, growing an N-type GaN layer doped with Si, growing a multi-quantum well layer, growing an AlGaN electronic barrier layer and growing a P-type GaN layer doped with Mg, and cooling, wherein the growing of the multi-quantum well layer sequentially comprises growing an InGaN well layer and growing an H well layer2Atmosphere InGaN: si layer, growth of N2Atmosphere InGaN: mg layer, growth H2And N2Mixed atmosphere InGaN: and growing an Mg/Si layer, an InGaN protective layer and a GaN barrier layer. The method solves the problem of large blue shift of the LED light-emitting wavelength in the conventional LED epitaxial growth, and simultaneously improves the blue shiftThe luminous efficiency of the LED reduces the working voltage and enhances the antistatic capability.

Description

LED epitaxial growth method suitable for small-spacing display screen
Technical Field
The invention belongs to the technical field of LEDs, and particularly relates to an LED epitaxial growth method suitable for a small-spacing display screen.
Background
A Light-Emitting Diode (LED) is a semiconductor electronic device that converts electrical energy into optical energy. As a new high-efficiency, environment-friendly, green solid-state illumination light source, LEDs have been widely used in traffic lights, automotive lights, indoor and outdoor lighting, display screens, and small-pitch display screens.
The small-spacing display screen adopts a pixel-level point control technology to realize the state control of the reducibility and the uniformity of the brightness and the color of a display screen pixel unit. The small-spacing display screen requires that the variation range of the light-emitting wavelength is small in the process of injecting currents with different magnitudes to change the light-emitting intensity.
In the traditional LED epitaxial InGaN/GaN multi-quantum well layer growth method, lattice structures of InGaN and GaN are wurtzite structures, the structures lack conversion symmetry, spontaneous polarization is easily generated in materials, and meanwhile, piezoelectric polarization phenomenon is caused by stress generated by mismatching of lattice constants of InGaN well layers and GaN barrier layers. The combined effect of spontaneous polarization and piezoelectric polarization causes a large electric field to exist inside the quantum well, resulting in the energy band of the quantum well being tilted. With the increase of the injection current, free carriers of the quantum well increase, and the ground state in the quantum well rises, so that the light-emitting wavelength of the LED is shifted to a short wave direction, namely blue shift occurs. When currents with different magnitudes are injected into the small-spacing display screen to change the luminous intensity, the blue shift amount of the LED luminous wavelength has large difference, and the application requirement of the small-spacing display screen cannot be met.
Therefore, an LED epitaxial growth method suitable for a small-pitch display screen is provided to solve the problem of large blue shift of LED emission wavelength in the existing LED epitaxial growth, so as to meet the application requirement of the small-pitch display screen, which is a technical problem to be solved urgently in the technical field.
Disclosure of Invention
The invention solves the problem of larger blue shift of LED light-emitting wavelength in the existing LED epitaxial growth by adopting a new method for growing the multi-quantum well layer, and simultaneously improves the light-emitting efficiency of the LED, reduces the working voltage and enhances the antistatic capability.
The invention discloses an LED epitaxial growth method suitable for a small-spacing display screen, which sequentially comprises the following steps: processing a substrate, growing a low-temperature buffer layer GaN, growing an undoped GaN layer, growing an N-type GaN layer doped with Si, growing a multi-quantum well layer, growing an AlGaN electronic barrier layer and growing a P-type GaN layer doped with Mg, and cooling; the growing multiple quantum well layer sequentially comprises: growth of InGaN well layer, growth of H2Atmosphere InGaN: si layer, growth of N2Atmosphere InGaN: mg layer, growth H2And N2Mixed atmosphere InGaN: the GaN-based light-emitting diode comprises an Mg/Si layer, a grown InGaN protective layer and a grown GaN barrier layer, and specifically comprises the following steps:
A. controlling the pressure of the reaction chamber at 280-350mbar, controlling the temperature of the reaction chamber at 700-750 ℃, and introducing NH with the flow rate of 50000-70000sccm3Growing an InGaN well layer with the thickness of 3nm by using 20-40sccm of TMGa and 10000-15000sccm of TMIn;
B. keeping the pressure of the reaction chamber unchanged, reducing the temperature of the reaction chamber to 600-650 ℃, and introducing NH with the flow rate of 50000-70000sccm3160-0 sccm TMGa, 8000-9000sccm TMIn and 200-240sccm SiH4And H2H with a thickness of 0.5-1nm is grown at a growth rate V12Atmosphere InGaN: a Si layer;
C. keeping the pressure and the temperature of the reaction chamber constant, and introducing NH with the flow of 40000-3120 TMGa of 140sccm, 6000 TMIn of 7000sccm and 180 Cp of 200sccm2Mg and N2N with a thickness of 1.2-1.5nm is grown at a growth rate V22Atmosphere InGaN: a Mg layer;
D. keeping the pressure of the reaction chamber unchanged, raising the temperature of the reaction chamber to 750-40000 sccm, and introducing NH with the flow rate of 36000-40000sccm380-100sccm TMGa, 4000-5000sccm TMIn, 140-160sccm Cp2Mg and 120-4And H2And N2The mixed gas of (2) is used for growing H with the thickness of 1.6-2nm at the growth rate of V32And N2Mixed atmosphere InGaN:Mg/Si layer of which H2And N2H in the mixed gas of2The proportion is 2.5% -8%;
E. keeping the pressure and the temperature of the reaction chamber unchanged, and introducing NH with the flow rate of 30000-360-70sccm of TMGa and 3000-4000sccm of TMIn, and growing the InGaN passivation layer with a thickness of 1nm at a growth rate of V4, wherein V4<V3<V2<V1；
F. Raising the temperature to 800 ℃, keeping the pressure of the reaction cavity at 300-320-60sccm of TMGa and 100-130L/min of N2Growing a 10nm GaN barrier layer;
repeating the steps A-F, and periodically and sequentially growing an InGaN well layer and an InGaN H layer2Atmosphere InGaN: si layer, N2Atmosphere InGaN: mg layer, H2And N2Mixed atmosphere InGaN: the growth cycle number of the Mg/Si layer, the InGaN protective layer and the GaN barrier layer is 2-10.
Preferably, the specific process for processing the substrate is as follows:
at the temperature of 1000-1100 ℃, 100-130L/min H is introduced2And processing the sapphire substrate for 5-10min by keeping the pressure of the reaction chamber at 100-.
Preferably, the specific process for growing the low-temperature buffer layer GaN is as follows:
cooling to 500-3TMGa of 50-100sccm and H of 100-2Growing a low-temperature buffer layer GaN with the thickness of 20-40nm on a sapphire substrate;
raising the temperature to 1000-3100-130L/min H2And keeping the temperature for 300-500s, and corroding the low-temperature buffer layer GaN into an irregular island shape.
Preferably, the specific process for growing the undoped GaN layer is as follows:
raising the temperature to 1000-3200-400sccm TMGa and 100-130L/min H2Continuously growing for 2-4 μmThe GaN layer is not doped.
Preferably, the specific process for growing the doped GaN layer is as follows:
the pressure of the reaction chamber is kept at 300-3200-400sccm TMGa, 100-130L/min H2And 20-50sccm SiH4Continuously growing Si-doped N-type GaN of 3-4 μm, wherein the doping concentration of Si is 5E18-1E19atoms/cm3。
Preferably, the specific process for growing the AlGaN electron blocking layer is as follows:
introducing NH of 50000-70000sccm at the temperature of 900-950 ℃ and the pressure of the reaction chamber of 200-400mbar3TMGa 30-60sccm, H100-130L/min2100-TMAl of 130sccm and 1000-Cp of 1300sccm2Growing the AlGaN electron barrier layer under the condition of Mg, wherein the thickness of the AlGaN layer is 40-60nm, and the Mg doping concentration is 1E19-1E20atoms/cm3。
Preferably, the specific process for growing the Mg-doped P-type GaN layer is as follows:
keeping the pressure of the reaction cavity at 400-320-100sccm of TMGa, 100-2And 1000-Cp of 3000sccm2Mg, continuously growing a P-type GaN layer doped with Mg with the concentration of 50-200nm, wherein the doping concentration of Mg is 1E19-1E20atoms/cm3。
Preferably, the specific process of cooling down is as follows:
cooling to 650 plus 680 ℃, preserving the temperature for 20-30min, closing the heating system and the gas supply system, and cooling along with the furnace.
Compared with the traditional growth method, the LED epitaxial growth method suitable for the small-spacing display screen achieves the following effects:
in the method for growing the multiple quantum well layer, H is inserted into the InGaN well layer and the GaN barrier layer2Atmosphere InGaN: si layer, N2Atmosphere InGaN: mg layer, H2And N2Mixed atmosphere InGaN: Mg/Si layer and InGaN protective layer, the lattice constant of the insertion layer can be well matched with that of the InGaN well layerIn addition, the lattice mismatch between the InGaN well layer and the GaN barrier layer can be effectively relieved, the pressure generated due to the lattice mismatch is reduced, piezoelectric polarization under the action of the pressure is avoided, the internal electric field is reduced, and the energy band inclination in the quantum well is reduced, so that the blue shift of the LED light-emitting wavelength is reduced, and the application requirement of a small-distance display screen is met.
The n-type dopant Si and the p-type dopant Mg are added in the insertion layer, so that ionization of Mg can be properly activated, mobility of holes can be improved, driving voltage can be reduced, hole concentration can be increased, injection of the holes into the light emitting layer can be improved, light emitting efficiency of the device can be improved, and overall light efficiency of the device can be improved.
Using H during the growth of the insertion layer2And N2The atmosphere treatment can make the quantum well barrier interface smooth, is beneficial to improving the photon performance of the quantum well active region and improving the luminous efficiency of the LED. The InGaN protective layer with the thickness of 1nm is grown before the barrier layer is grown, so that the light quantum well can be well protected and prevented from being subjected to H2And etching is performed, so that the integral crystal quality of the quantum well is improved, and the antistatic capacity of the device is improved.
The growth rate of the insertion layer is reduced in sequence, so that the whole quantum well layer can form a gradient capacitor structure, the current limiting effect can be achieved, and the light emitting attenuation effect under high current density is reduced to a great extent; the LED light source can block the radial movement of charges, so that the charges are diffused to the periphery, namely, the transverse current expansion capability is enhanced, the LED light emitting efficiency is improved, the forward driving voltage is lower, and the blue shift of the wavelength is smaller.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, 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 structural diagram of an LED epitaxy prepared by the method of the present invention;
FIG. 2 is a schematic structural diagram of an LED epitaxy prepared by a conventional method;
the GaN-based light emitting diode comprises a sapphire substrate 1, a low-temperature GaN buffer layer 2, an undoped GaN layer 3, an n-type GaN layer 4, a multi-quantum well light emitting layer 5, an AlGaN electron blocking layer 6, a P-type GaN layer 51, an InGaN well layer 52, an H-type GaN layer, an AlGaN electron blocking layer 7, a P-type GaN layer 51, an InGaN well layer 52 and an InGaN well layer2Atmosphere InGaN: si layer, 53, N2Atmosphere InGaN: mg layer, 54, H2And N2Mixed atmosphere InGaN: the LED structure comprises an Mg/Si layer, 55 an InGaN protective layer, 56 a GaN barrier layer.
Detailed Description
As used in the specification and in the claims, certain terms are used to refer to particular components. As one skilled in the art will appreciate, manufacturers may refer to a component by different names. This specification and claims do not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. "substantially" means within an acceptable error range, and a person skilled in the art can solve the technical problem within a certain error range to substantially achieve the technical effect. The description which follows is a preferred embodiment of the present application, but is made for the purpose of illustrating the general principles of the application and not for the purpose of limiting the scope of the application. The protection scope of the present application shall be subject to the definitions of the appended claims.
Furthermore, the present description does not limit the components and method steps disclosed in the claims to those of the embodiments. In particular, the dimensions, materials, shapes, structural and adjacent orders, manufacturing methods, and the like of the components described in the embodiments are merely illustrative examples, and the scope of the present invention is not limited thereto, unless otherwise specified. The sizes and positional relationships of the structural members shown in the drawings are exaggerated for clarity of illustration.
The present application will be described in further detail below with reference to the accompanying drawings, but the present application is not limited thereto.
Example 1
This example uses the present inventionThe provided LED epitaxial growth method suitable for the small-spacing display screen adopts MOCVD to grow the GaN-based LED epitaxial wafer and adopts high-purity H2Or high purity N2Or high purity H2And high purity N2The mixed gas of (2) is used as a carrier gas, high-purity NH3As the N source, a metal organic source, trimethyl gallium (TMGa) as the gallium source, trimethyl indium (TMIn) as the indium source, and an N-type dopant, Silane (SiH)4) Trimethylaluminum (TMAl) as the aluminum source and magnesium diclomelate (CP) as the P-type dopant2Mg), the reaction pressure is between 70mbar and 900 mbar. The specific growth method is as follows (please refer to fig. 1 for the epitaxial structure):
a method for growing an LED multi-quantum well layer for improving luminous efficiency sequentially comprises the following steps: processing a sapphire substrate 1, growing a low-temperature buffer layer GaN layer 2, growing an undoped GaN layer 3, growing an Si-doped N-type GaN layer 4, growing a multi-quantum well light-emitting layer 5, growing an AlGaN electron barrier layer 6 and growing an Mg-doped P-type GaN layer 7, and cooling; wherein the content of the first and second substances,
step 1: the sapphire substrate 1 is processed.
Specifically, the step 1 further includes:
introducing 100-130L/min H at the temperature of 1000-1100 ℃ and the pressure of the reaction cavity of 100-300mbar2The sapphire substrate was processed for 5 to 10 minutes under the conditions of (1).
Step 2: and growing the low-temperature GaN buffer layer 2, and forming irregular islands on the low-temperature GaN buffer layer 2.
Specifically, the step 2 further includes:
introducing 10000-20000sccm NH into the reaction chamber at the temperature of 500-600 ℃ and the pressure of 300-600mbar3TMGa of 50-100sccm and H of 100-2Growing the low-temperature GaN buffer layer 2 on the sapphire substrate under the condition (2), wherein the thickness of the low-temperature GaN buffer layer 2 is 20-40 nm;
introducing NH of 30000-40000sccm at the temperature of 1000-1100 ℃ and the pressure of the reaction chamber of 300-600mbar3And H of 100-2Under the conditions of (1), the irregular islands are formed on the low-temperature GaN buffer layer 2.
And step 3: an undoped GaN layer 3 is grown.
Specifically, the step 3 further includes:
introducing NH of 30000-40000sccm at the temperature of 1000-1200 ℃ and the pressure of the reaction chamber of 300-600mbar3200-400sccm TMGa and 100-130L/min H2The non-doped GaN layer 3 grown under the condition of (a); the thickness of the undoped GaN layer 3 is 2-4 μm.
And 4, step 4: a Si doped N-type GaN layer 4 is grown.
Specifically, the step 4 is further:
the pressure of the reaction chamber is kept at 300-3200-400sccm TMGa, 100-130L/min H2And 20-50sccm SiH4Continuously growing a 3-4 μm Si-doped N-type GaN layer 4 in which the Si doping concentration is 5E18-1E19atoms/cm3。
And 5: a multiple quantum well light emitting layer 5 is grown.
The growing multiple quantum well luminescent layer 5 further comprises:
A. controlling the pressure of the reaction chamber at 280-350mbar, controlling the temperature of the reaction chamber at 700-750 ℃, and introducing NH with the flow rate of 50000-70000sccm3Growing an InGaN well layer 51 with the thickness of 3nm by using 20-40sccm of TMGa and 10000-15000sccm of TMIn;
B. keeping the pressure of the reaction chamber unchanged, reducing the temperature of the reaction chamber to 600-650 ℃, and introducing NH with the flow rate of 50000-70000sccm3160-0 sccm TMGa, 8000-9000sccm TMIn and 200-240sccm SiH4And H2H with a thickness of 0.5-1nm is grown at a growth rate V12Atmosphere InGaN: a Si layer 52;
C. keeping the pressure and the temperature of the reaction chamber constant, and introducing NH with the flow of 40000-3120 TMGa of 140sccm, 6000 TMIn of 7000sccm and 180 Cp of 200sccm2Mg and N2N with a thickness of 1.2-1.5nm is grown at a growth rate V22Atmosphere InGaN: a Mg layer 53;
D. keeping the pressure of the reaction chamber unchanged, raising the temperature of the reaction chamber to 750-40000 sccm, and introducing NH with the flow rate of 36000-40000sccm380-100sccm TMGa, 4000-5000sccm TMIn, 140-160sccm Cp2Mg and 120-4And H2And N2The mixed gas of (2) is used for growing H with the thickness of 1.6-2nm at the growth rate of V32And N2Mixed atmosphere InGaN: Mg/Si layer 54, wherein H2And N2H in the mixed gas of2The proportion is 2.5% -8%;
E. keeping the pressure and the temperature of the reaction chamber unchanged, and introducing NH with the flow rate of 30000-360-70sccm of TMGa and 3000-4000sccm of TMIn, and growing the InGaN passivation layer 55 with a thickness of 1nm at a growth rate of V4, wherein V4<V3<V2<V1；
F. Raising the temperature to 800 ℃, keeping the pressure of the reaction cavity at 300-320-60sccm of TMGa and 100-130L/min of N2Growing a 10nm GaN barrier layer 56;
repeating the above steps A-F to periodically and sequentially grow InGaN well layers 51, H2Atmosphere InGaN: si layer 52, N2Atmosphere InGaN: mg layer 53, H2And N2Mixed atmosphere InGaN: the Mg/Si layer 54, the InGaN protective layer 55 and the GaN barrier layer 56, and the growth cycle number is 2-10.
Specifically, the step 6 further includes:
introducing NH of 50000-70000sccm at the temperature of 900-950 ℃ and the pressure of the reaction chamber of 200-400mbar3TMGa 30-60sccm, H100-130L/min2100-TMAl of 130sccm and 1000-Cp of 1300sccm2Growing the AlGaN electron barrier layer 6 under the condition of Mg, wherein the thickness of the AlGaN layer 6 is 40-60nm, and the Mg doping concentration is 1E19-1E20atoms/cm3。
And 7: a Mg doped P-type GaN layer 7 is grown.
Specifically, the step 7 is further:
introducing NH of 50000-70000sccm at the temperature of 950-1000 ℃ and the pressure of the reaction chamber of 400-900mbar320-100sccm of TMGa, 100-2And 1000-Cp of 3000sccm2Growing a Mg-doped P-type GaN layer 7 with the thickness of 50-200nm under the condition of Mg,mg doping concentration of 1E19-1E20atoms/cm3。
And 8: keeping the temperature for 20-30min at 650-680 ℃, then closing the heating system and the gas supply system, and cooling along with the furnace.
Example 2
The following provides a comparative example, an existing conventional LED epitaxial growth method.
Step 1: introducing 100-130L/min H at the temperature of 1000-1100 ℃ and the pressure of the reaction cavity of 100-300mbar2The sapphire substrate was processed for 5 to 10 minutes under the conditions of (1).
Step 2: and growing the low-temperature GaN buffer layer 2, and forming irregular islands on the low-temperature GaN buffer layer 2.
Specifically, the step 2 further includes:
introducing 10000-20000sccm NH into the reaction chamber at the temperature of 500-600 ℃ and the pressure of 300-600mbar3TMGa of 50-100sccm and H of 100-2Growing the low-temperature GaN buffer layer 2 on the sapphire substrate under the condition (2), wherein the thickness of the low-temperature GaN buffer layer 2 is 20-40 nm;
introducing NH of 30000-40000sccm at the temperature of 1000-1100 ℃ and the pressure of the reaction chamber of 300-600mbar3And H of 100L/min-130L/min2Under the conditions of (1), the irregular islands are formed on the low-temperature GaN buffer layer 2.
And step 3: an undoped GaN layer 3 is grown.
Specifically, the step 3 further includes:
introducing NH of 30000-40000sccm at the temperature of 1000-1200 ℃ and the pressure of the reaction chamber of 300-600mbar3200-400sccm TMGa, 100-130L/min H2The non-doped GaN layer 3 grown under the condition of (a); the thickness of the undoped GaN layer 3 is 2-4 μm.
And 4, step 4: a Si doped N-type GaN layer 4 is grown.
Specifically, the step 4 is further:
introducing NH of 30000-60000sccm at the temperature of 1000-1200 ℃ and the pressure of the reaction chamber of 300-600mbar3200-400sccm TMGa, 10H of 0-130L/min2And 20-50sccm SiH4Under the conditions of (1) growing a Si-doped N-type GaN layer 4, the thickness of the N-type GaN layer 4 being 3-4 μm, the concentration of Si doping being 5E18-1E19atoms/cm3。
And 5: an InGaN/GaN multiple quantum well light emitting layer 5 is grown.
Specifically, the growing the multiple quantum well light emitting layer further comprises:
keeping the pressure of the reaction cavity at 300-3Growing an InGaN well layer 51 doped with In and having a thickness of 3nm, wherein the thickness of the InGaN well layer is 20-40sccm of TMGa and 10000-15000sccm of TMIn;
raising the temperature to 800 ℃, keeping the pressure of the reaction cavity at 300-320-100sccm of TMGa and 100-130L/min of N2Growing a 10nm GaN barrier layer 56;
and repeatedly and alternately growing the InGaN well layer 51 and the GaN barrier layer 56 to obtain the InGaN/GaN multi-quantum well light-emitting layer, wherein the number of the alternate growth cycles of the InGaN well layer 51 and the GaN barrier layer 56 is 7-13.
Step 6: an AlGaN electron blocking layer 6 is grown.
Specifically, the step 6 further includes:
introducing NH of 50000-70000sccm at the temperature of 900-950 ℃ and the pressure of the reaction chamber of 200-400mbar3TMGa 30-60sccm, H100-130L/min2100-TMAl of 130sccm and 1000-Cp of 1300sccm2Growing the AlGaN electron barrier layer 6 under the condition of Mg, wherein the thickness of the AlGaN layer 6 is 40-60nm, and the Mg doping concentration is 1E19-1E20atoms/cm3。
And 7: a Mg doped P-type GaN layer 7 is grown.
Specifically, the step 7 is further:
introducing NH of 50000-70000sccm at the temperature of 950-1000 ℃ and the pressure of the reaction chamber of 400-900mbar320-100sccm of TMGa, 100-2And 1000-Cp of 3000sccm2Growing a Mg-doped P-type GaN layer 7 with the thickness of 50-200nm under the condition of Mg, wherein the Mg doping concentration is 1E19-1E20atoms/cm3。
And 8: keeping the temperature for 20-30min at 650-680 ℃, then closing the heating system and the gas supply system, and cooling along with the furnace.
Samples 1 and 2 were prepared according to the above examples 1 and 2, respectively, with sample 1 and 2 being about 150nm coated with an ITO layer under the same pre-process conditions, about 1500nm coated with a Cr/Pt/Au electrode under the same conditions, and a protective layer of SiO coated under the same conditions2About 100nm, the sample was then ground and cut under the same conditions into 635 μm by 635 μm (25mil by 25mil) chip particles, and then 100 dies were picked from the same positions of sample 1 and sample 2, respectively, and packaged into a white LED under the same packaging process. The photoelectric properties of sample 1 and sample 2 were tested using an integrating sphere at a drive current of 350 mA.
TABLE 1 comparison of electrical parameters of sample 1 and sample 2
Figure BDA0002578953870000101
The data obtained by the integrating sphere are analyzed and compared, and as can be seen from table 1, the LED (sample 1) prepared by the LED epitaxial growth method provided by the invention has the advantages of smaller blue shift of wavelength, obviously improved luminous efficiency, lower work and stronger antistatic capability, because the technical scheme inserts H into the InGaN well layer and the GaN barrier layer2Atmosphere InGaN: si layer, N2Atmosphere InGaN: mg layer, H2And N2Mixed atmosphere InGaN: a Mg/Si layer and an InGaN protective layer.
Compared with the traditional growth method, the LED epitaxial growth method suitable for the small-spacing display screen achieves the following effects:
in the method for growing the multiple quantum well layer, H is inserted into the InGaN well layer and the GaN barrier layer2Atmosphere InGaN: si layer, N2Atmosphere InGaN: mg layer, H2And N2Mixed atmosphere InGaN: the lattice constant of the insertion layer can be well matched with that of the InGaN well layer, the lattice mismatch between the InGaN well layer and the GaN barrier layer can be effectively relieved, and the lattice mismatch is reducedThe pressure generated by matching avoids piezoelectric polarization under the action of pressure, reduces an internal electric field, and reduces the energy band inclination in the quantum well, thereby reducing the blue shift amount of the LED light-emitting wavelength and meeting the application requirement of a small-spacing display screen.
The n-type dopant Si and the p-type dopant Mg are added in the insertion layer, so that ionization of Mg can be properly activated, mobility of holes can be improved, driving voltage can be reduced, hole concentration can be increased, injection of the holes into the light emitting layer can be improved, light emitting efficiency of the device can be improved, and overall light efficiency of the device can be improved.
Using H during the growth of the insertion layer2And N2The atmosphere treatment can make the quantum well barrier interface smooth, is beneficial to improving the photon performance of the quantum well active region and improving the luminous efficiency of the LED. The InGaN protective layer with the thickness of 1nm is grown before the barrier layer is grown, so that the light quantum well can be well protected and prevented from being subjected to H2And etching is performed, so that the integral crystal quality of the quantum well is improved, and the antistatic capacity of the device is improved.
The growth rate of the insertion layer is reduced in sequence, so that the whole quantum well layer can form a gradient capacitor structure, the current limiting effect can be achieved, and the light emitting attenuation effect under high current density is reduced to a great extent; the LED light source can block the radial movement of charges, so that the charges are diffused to the periphery, namely, the transverse current expansion capability is enhanced, the LED light emitting efficiency is improved, the forward driving voltage is lower, and the blue shift of the wavelength is smaller.
Since the method has already been described in detail in the embodiments of the present application, the expanded description of the structure and method corresponding parts related to the embodiments is omitted here, and will not be described again. The description of specific contents in the structure may refer to the contents of the method embodiments, which are not specifically limited herein.
The foregoing description shows and describes several preferred embodiments of the present application, but as aforementioned, it is to be understood that the application is not limited to the forms disclosed herein, but is not to be construed as excluding other embodiments and is capable of use in various other combinations, modifications, and environments and is capable of changes within the scope of the application as described herein, commensurate with the above teachings, or the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the application, which is to be protected by the claims appended hereto.

Claims (8)

1. The LED epitaxial growth method suitable for the small-spacing display screen is characterized by sequentially comprising the following steps of: processing a substrate, growing a low-temperature buffer layer GaN, growing an undoped GaN layer, growing an N-type GaN layer doped with Si, growing a multi-quantum well layer, growing an AlGaN electronic barrier layer and growing a P-type GaN layer doped with Mg, and cooling; the growing multiple quantum well layer sequentially comprises: growth of InGaN well layer, growth of H2Atmosphere InGaN: si layer, growth of N2Atmosphere InGaN: mg layer, growth H2And N2Mixed atmosphere InGaN: the GaN-based light-emitting diode comprises an Mg/Si layer, a grown InGaN protective layer and a grown GaN barrier layer, and specifically comprises the following steps:
A. controlling the pressure of the reaction chamber at 280-350mbar, controlling the temperature of the reaction chamber at 700-750 ℃, and introducing NH with the flow rate of 50000-70000sccm3Growing an InGaN well layer with the thickness of 3nm by using 20-40sccm of TMGa and 10000-15000sccm of TMIn;
B. keeping the pressure of the reaction chamber unchanged, reducing the temperature of the reaction chamber to 600-650 ℃, and introducing NH with the flow rate of 50000-70000sccm3160-0 sccm TMGa, 8000-9000sccm TMIn and 200-240sccm SiH4And H2H with a thickness of 0.5-1nm is grown at a growth rate V12Atmosphere InGaN: a Si layer;
C. keeping the pressure and the temperature of the reaction chamber constant, and introducing NH with the flow of 40000-3120 TMGa of 140sccm, 6000 TMIn of 7000sccm and 180 Cp of 200sccm2Mg and N2N with a thickness of 1.2-1.5nm is grown at a growth rate V22Atmosphere InGaN: a Mg layer;
D. keeping the pressure of the reaction chamber unchanged, raising the temperature of the reaction chamber to 750-40000 sccm, and introducing NH with the flow rate of 36000-40000sccm380-100sccm TMGa, 4000-5000sccm TMIn, 140-160sccm Cp2Mg and 120-4And H2And N2The mixed gas of (a) and (b),growth of H with a thickness of 1.6-2nm at a growth rate V32And N2Mixed atmosphere InGaN: Mg/Si layer of which H2And N2H in the mixed gas of2The proportion is 2.5% -8%;
E. keeping the pressure and the temperature of the reaction chamber unchanged, and introducing NH with the flow rate of 30000-360-70sccm of TMGa and 3000-4000sccm of TMIn, and growing the InGaN passivation layer with a thickness of 1nm at a growth rate of V4, wherein V4<V3<V2<V1；
F. Raising the temperature to 800 ℃, keeping the pressure of the reaction cavity at 300-320-60sccm of TMGa and 100-130L/min of N2Growing a 10nm GaN barrier layer;
repeating the steps A-F, and periodically and sequentially growing an InGaN well layer and an InGaN H layer2Atmosphere InGaN: si layer, N2Atmosphere InGaN: mg layer, H2And N2Mixed atmosphere InGaN: the growth cycle number of the Mg/Si layer, the InGaN protective layer and the GaN barrier layer is 2-10.
2. The method as claimed in claim 1, wherein the temperature is 1000-1100 ℃, and 100-130L/min H is introduced2And processing the sapphire substrate for 5-10min by keeping the pressure of the reaction chamber at 100-.
3. The LED epitaxial growth method suitable for the small-spacing display screen according to claim 2, wherein the specific process for growing the low-temperature buffer layer GaN is as follows:
cooling to 500-3TMGa of 50-100sccm and H of 100-2Growing a low-temperature buffer layer GaN with the thickness of 20-40nm on a sapphire substrate;
raising the temperature to 1000-3And H of 100-2And keeping the temperature for 300-500s, and corroding the low-temperature buffer layer GaN into an irregular island shape.
4. The LED epitaxial growth method suitable for small-pitch display screens according to claim 1, wherein the specific process for growing the undoped GaN layer is as follows:
raising the temperature to 1000-3200-400sccm TMGa and 100-130L/min H2And continuously growing 2-4 mu m undoped GaN layer.
5. The LED epitaxial growth method suitable for small-pitch display screens according to claim 1, wherein the specific process for growing the Si-doped N-type GaN layer is as follows:
the pressure of the reaction chamber is kept at 300-3200-400sccm TMGa, 100-130L/min H2And 20-50sccm SiH4Continuously growing Si-doped N-type GaN of 3-4 μm, wherein the doping concentration of Si is 5E18-1E19atoms/cm3。
6. The LED epitaxial growth method suitable for the small-spacing display screen according to claim 1, wherein the specific process for growing the AlGaN electron blocking layer is as follows:
introducing NH of 50000-70000sccm at the temperature of 900-950 ℃ and the pressure of the reaction chamber of 200-400mbar3TMGa 30-60sccm, H100-130L/min2100-TMAl of 130sccm and 1000-Cp of 1300sccm2Growing the AlGaN electron barrier layer under the condition of Mg, wherein the thickness of the AlGaN layer is 40-60nm, and the Mg doping concentration is 1E19-1E20atoms/cm3。
7. The LED epitaxial growth method suitable for small-pitch display screens of claim 1, wherein the specific process for growing the Mg-doped P-type GaN layer is as follows:
keeping the pressure of the reaction cavity at 400-320-100sccm of TMGa, 100-2And 1000-Cp of 3000sccm2Mg, continuously growing a P-type GaN layer doped with Mg with the concentration of 50-200nm, wherein the doping concentration of Mg is 1E19-1E20atoms/cm3。
8. The LED epitaxial growth method suitable for the small-pitch display screen according to claim 1, wherein the specific process of cooling down is as follows:
cooling to 650 plus 680 ℃, preserving the temperature for 20-30min, closing the heating system and the gas supply system, and cooling along with the furnace.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115224171A (en) * 2022-09-20 2022-10-21 江西兆驰半导体有限公司 High-luminous-efficiency light-emitting diode epitaxial wafer, preparation method thereof and light-emitting diode

Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010212499A (en) * 2009-03-11 2010-09-24 Sony Corp Semiconductor laser device
CN103715322A (en) * 2013-12-30 2014-04-09 苏州矩阵光电有限公司 Novel GaN-based LED structure and manufacturing method thereof
JP2014120646A (en) * 2012-12-18 2014-06-30 Stanley Electric Co Ltd Semiconductor light-emitting element
CN103952684A (en) * 2014-04-23 2014-07-30 湘能华磊光电股份有限公司 LED (light-emitting diode) epitaxial layer growth method and LED epitaxial layer
CN104201261A (en) * 2014-09-10 2014-12-10 天津三安光电有限公司 Light-emitting diode
WO2015059296A1 (en) * 2013-10-25 2015-04-30 Commissariat à l'énergie atomique et aux énergies alternatives Light-emitting device
CN106684218A (en) * 2017-03-01 2017-05-17 湘能华磊光电股份有限公司 LED epitaxial growth method capable of improving light-emitting efficiency
CN106784184A (en) * 2016-12-21 2017-05-31 湘能华磊光电股份有限公司 LED epitaxial structure of recombination P-type GaN layer and preparation method thereof
CN107240627A (en) * 2017-05-16 2017-10-10 东南大学 A kind of UV LED with codope multi-quantum pit structure
US20170309785A1 (en) * 2016-04-20 2017-10-26 Dowa Electronics Materials Co., Ltd. Group iii nitride semiconductor light emitting device and method for manufacture the same
WO2020067215A1 (en) * 2018-09-28 2020-04-02 Ｄｏｗａエレクトロニクス株式会社 Iii nitride semiconductor light-emitting element, and method for producing same
CN110957403A (en) * 2019-12-24 2020-04-03 湘能华磊光电股份有限公司 LED epitaxial structure growth method
CN210379098U (en) * 2019-06-28 2020-04-21 厦门大学 Electronic control spin light-emitting diode device based on spin injection
CN111223764A (en) * 2020-03-18 2020-06-02 湘能华磊光电股份有限公司 LED epitaxial growth method for improving radiation recombination efficiency

Patent Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010212499A (en) * 2009-03-11 2010-09-24 Sony Corp Semiconductor laser device
JP2014120646A (en) * 2012-12-18 2014-06-30 Stanley Electric Co Ltd Semiconductor light-emitting element
WO2015059296A1 (en) * 2013-10-25 2015-04-30 Commissariat à l'énergie atomique et aux énergies alternatives Light-emitting device
CN103715322A (en) * 2013-12-30 2014-04-09 苏州矩阵光电有限公司 Novel GaN-based LED structure and manufacturing method thereof
CN103952684A (en) * 2014-04-23 2014-07-30 湘能华磊光电股份有限公司 LED (light-emitting diode) epitaxial layer growth method and LED epitaxial layer
CN104201261A (en) * 2014-09-10 2014-12-10 天津三安光电有限公司 Light-emitting diode
US20170309785A1 (en) * 2016-04-20 2017-10-26 Dowa Electronics Materials Co., Ltd. Group iii nitride semiconductor light emitting device and method for manufacture the same
CN106784184A (en) * 2016-12-21 2017-05-31 湘能华磊光电股份有限公司 LED epitaxial structure of recombination P-type GaN layer and preparation method thereof
CN106684218A (en) * 2017-03-01 2017-05-17 湘能华磊光电股份有限公司 LED epitaxial growth method capable of improving light-emitting efficiency
CN107240627A (en) * 2017-05-16 2017-10-10 东南大学 A kind of UV LED with codope multi-quantum pit structure
WO2020067215A1 (en) * 2018-09-28 2020-04-02 Ｄｏｗａエレクトロニクス株式会社 Iii nitride semiconductor light-emitting element, and method for producing same
CN210379098U (en) * 2019-06-28 2020-04-21 厦门大学 Electronic control spin light-emitting diode device based on spin injection
CN110957403A (en) * 2019-12-24 2020-04-03 湘能华磊光电股份有限公司 LED epitaxial structure growth method
CN111223764A (en) * 2020-03-18 2020-06-02 湘能华磊光电股份有限公司 LED epitaxial growth method for improving radiation recombination efficiency

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
YUJUEYANG,YIPINGZENG: "Enhancement ofholeinjectionwithMg–Si-codoped barriers in InGaN-basedlight-emittingdiodes", 《OPTICSCOMMUNICATIONS》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115224171A (en) * 2022-09-20 2022-10-21 江西兆驰半导体有限公司 High-luminous-efficiency light-emitting diode epitaxial wafer, preparation method thereof and light-emitting diode
CN115224171B (en) * 2022-09-20 2022-11-29 江西兆驰半导体有限公司 High-light-efficiency light-emitting diode epitaxial wafer, preparation method thereof and light-emitting diode

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