CN113097350A - Manufacturing method of LED epitaxial wafer for improving brightness - Google Patents
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- 238000004519 manufacturing process Methods 0.000 title claims abstract description 61
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 71
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical group [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 71
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- 238000005229 chemical vapour deposition Methods 0.000 claims description 3
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- 238000001755 magnetron sputter deposition Methods 0.000 claims description 3
- 150000002902 organometallic compounds Chemical class 0.000 claims description 3
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- H01L33/00—Semiconductor devices having potential barriers 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 having potential barriers 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
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Abstract
The invention provides a method for manufacturing an LED epitaxial wafer with improved brightness, wherein a raised cone, an aluminum region layer and a sunken and inverted cone cavity which are sequentially and circularly arranged are arranged on an AlN layer of the LED epitaxial wafer in sequence, and are not connected with each other; the manufacturing method comprises the following steps of 3, manufacturing a plurality of convex cones on the AlN layer at intervals; step 4, manufacturing a plurality of concave and inverted conical cavities on the AlN layer at intervals, wherein the conical cavities and the cones are arranged in a staggered mode and are not connected in pairs; step 5, manufacturing a plurality of aluminum area layers on the AlN layer at intervals, wherein each aluminum area layer is adjacent to the conical cavity and/or the cone; and 6, periodically growing a plurality of multi-quantum well light-emitting layers on the AlN layer. The LED epitaxial wafer has the advantages that the brightness of the LED epitaxial wafer can be improved, the antistatic capability is enhanced, the concentration of wavelength is improved, and the forward voltage of the LED epitaxial wafer can be reduced.
Description
Technical Field
The invention relates to the technical field of optoelectronic devices, in particular to a method for manufacturing an LED epitaxial wafer capable of improving brightness.
Background
An LED epitaxial wafer is a solid-state light source, which is a light emitting device made using semiconductor P-N junctions. When a forward current is conducted, minority carriers (i.e., electrons) and majority carriers (i.e., holes) in the semiconductor recombine, and the released energy is emitted as photons or partially as photons. The LED epitaxial wafer illumination has the remarkable advantages of high efficiency, energy conservation, environmental protection, long service life and the like, and is widely applied to various aspects such as street lamps, display screens, indoor illumination, automobile lamps and the like. Considering that the brightness is the most important measurement index of the competitiveness of the LED epitaxial wafer, how to improve the brightness of the LED epitaxial wafer on the basis of the prior art is a constant topic for increasing the competitiveness of the LED epitaxial wafer.
At present, the LED epitaxial wafer prepared by the existing LED epitaxial wafer manufacturing method has low brightness, the improvement of the LED performance is seriously hindered, and the energy-saving effect of the LED is reduced.
In summary, there is a need for a method for manufacturing an LED epitaxial wafer with improved brightness to solve the problem of low brightness of the LED epitaxial wafer in the prior art.
Disclosure of Invention
The invention aims to provide a method for manufacturing an LED epitaxial wafer with improved brightness, which has the following specific technical scheme:
a manufacturing method of an LED epitaxial wafer for improving brightness is characterized in that an AlN layer of the LED epitaxial wafer is provided with a raised cone, an aluminum region layer and a sunken and inverted cone cavity which are sequentially and circularly arranged, and the raised cone, the aluminum region layer and the sunken and inverted cone cavity are not connected with each other;
the manufacturing method comprises the following steps of,
step 3, manufacturing a plurality of convex cones on the AlN layer at intervals;
step 4, manufacturing a plurality of concave and inverted conical cavities on the AlN layer at intervals, wherein the conical cavities and the cones are arranged in a staggered mode and are not connected in pairs;
step 5, manufacturing a plurality of aluminum area layers on the AlN layer at intervals, wherein each aluminum area layer is adjacent to the conical cavity and/or the cone;
and 6, periodically growing a plurality of multi-quantum well light emitting layers on the AlN layer, wherein each multi-quantum well light emitting layer comprises an InGaN well layer and a GaN barrier layer which are sequentially grown, the multi-quantum well light emitting layer grown in the first period is used for filling the conical cavity in the step 4, and the multi-quantum well light emitting layers grown in the later period are all located on the whole structure comprising the AlN layer, the aluminum region layer and the multi-quantum well light emitting layer grown in the previous period from the second period.
Preferably, in the step 3, the diameter D1 of the bottom surface of the cone is 1000-1100nm, the height H1 is 850-900nm, and the shortest distance D1 between the bottom surfaces of the adjacent cones is 2100-2200 nm.
Preferably, in the step 4, the diameter D2 of the top surface of the conical cavity is 800-.
Preferably, in step 6, the layer thickness D3 of the InGaN well layer grown in the first period is equal to the layer thickness D4 of the GaN barrier layer grown in the first period, and D3+ D4 is H2.
Preferably, in the step 5, the distance between each aluminum region layer and the adjacent conical cavity is equal to the distance between the aluminum region layer and the adjacent conical cavity, the length and the width of the aluminum region layer are equal to 400-420mm, and the thickness of the aluminum region layer is 60-80 nm.
Preferably, in the step 6, the number of growth cycles of the multiple quantum well light emitting layer is 2 to 12, and from the second period, in a single growth cycle, the layer thickness of the InGaN well layer is 3 to 5nm, and the layer thickness of the GaN barrier layer is 8 to 10 nm.
Preferably, the method for manufacturing the cone in step 3 is as follows: the method comprises the steps of firstly coating photoresist on an AlN layer, then carrying out exposure and development treatment on the photoresist in a non-cone manufacturing area on the AlN layer, then manufacturing a cone at a corresponding position through dry etching, and finally cleaning residual colloid on the AlN layer.
Preferably, the manufacturing method of the conical cavity in the step 4 is as follows: the method comprises the steps of firstly coating photoresist on an AlN layer, then carrying out exposure and development treatment on the photoresist in a non-conical cavity manufacturing area on the AlN layer, then manufacturing a conical cavity at a corresponding position through dry etching, and finally cleaning residual colloid on the AlN layer.
Preferably, the method for manufacturing the aluminum region layer in step 5 is as follows: firstly growing an aluminum layer on the AlN layer by a magnetron sputtering method, then coating photoresist on the aluminum layer, carrying out exposure and development treatment on the photoresist in a non-aluminum region layer manufacturing region on the aluminum layer, then manufacturing an aluminum region layer at a corresponding position by dry etching, and finally cleaning the aluminum region layer and residual colloid on the AlN layer.
Preferably, the method further comprises the following steps before the step 3:
step 1, manufacturing a patterned substrate;
step 2, growing a buffer layer GaN, a non-doped GaN layer, a Si-doped N-type GaN layer and an AlN layer on the patterned substrate in sequence, wherein the thickness of the AlN layer is 1800-2000 nm;
step 7 is further included after the step 6, and the step 7 is to sequentially grow an electron blocking layer and a P-type semiconductor layer on the multiple quantum well light-emitting layer in the step 6 to prepare an LED epitaxial wafer;
and 2, during operation, performing deposition operation by adopting a metal organic compound chemical vapor deposition method along a direction vertical to the surface of the patterned substrate.
The technical scheme of the invention has the following beneficial effects:
the manufacturing method of the LED epitaxial wafer for improving the brightness has the following beneficial effects:
(1) by manufacturing the cones and the conical cavities on the AlN layer at intervals in the steps 3 and 4, the luminous efficiency, namely the brightness, of the LED epitaxial wafer can be improved, the antistatic capacity of the LED epitaxial wafer can be improved, and the wavelength concentration of the LED epitaxial wafer is improved, namely the wavelength uniformity is improved.
(2) And 6, growing multiple-quantum-well light-emitting layers with multiple periods on the AlN layer, so that holes in the multiple-quantum-well light-emitting layers are easily injected into deeper multiple-quantum-well light-emitting layers through the side walls of the conical cavities, the working voltage of the LED epitaxial wafer can be reduced, and the spatial uneven distribution of electrons and holes can be improved. In addition, the cone can release the mismatch stress In the multiple quantum well light emitting layer, so that more In components can be incorporated, the growth of the long-wavelength InGaN yellow-green light quantum well layer is very favorable, the same wavelength can be obtained more easily, the wavelength concentration of the LED epitaxial wafer is improved, the growth temperature of the InGaN quantum well is improved more easily, the crystal quality of the grown LED epitaxial wafer is better, and the photoelectric performance of the LED epitaxial wafer is better. The multiple quantum well luminescent layer grown In the first period In the step 6 just fills the conical cavity, so that crystal defects such as In-rich clusters and the like In the conical cavity can be effectively removed, the crystal quality of the multiple quantum well luminescent layer In the conical cavity region is improved, non-radiative recombination is inhibited to a certain extent, and the luminous efficiency of the multiple quantum well luminescent layer is enhanced.
(3) The design of the cone in the step 3 is beneficial to releasing the stress in the LED epitaxial wafer by the atoms in the multi-quantum well light-emitting layer, the atoms are uniformly filled upwards, and the uniformity of the atoms in the LED epitaxial wafer can be improved. The design of the conical cavity in the step 4 is beneficial to blocking the upward extension of the defects when the multiple quantum well light-emitting layer is directly pushed upwards in parallel, the dislocation density is reduced, and the crystal quality of the LED epitaxial wafer is improved. The combination of the step 3, the step 4 and the step 6 can improve the brightness of the LED epitaxial wafer, enhance the antistatic capability, improve the concentration ratio of the wavelength and reduce the forward voltage of the LED epitaxial wafer.
(4) Manufacturing a plurality of aluminum area layers on the AlN layer at intervals, wherein on one hand, the aluminum area layers reflect a part of light emitted downwards from the light emitting layer of the multiple quantum wells by virtue of good light reflectivity of the aluminum area layers, so that the brightness of the LED epitaxial wafer is improved; on the other hand, the aluminum region layer can further prevent dislocation defects in the conical cavity from extending to the cone when the multiple quantum well light-emitting layer starts to grow from the second period, and lateral growth of the multiple quantum well light-emitting layer on the cone can be reduced, so that the crystal quality of the multiple quantum well light-emitting layer can be improved, the light-emitting efficiency and the antistatic capacity of the LED epitaxial wafer can be improved, and the concentration of wavelengths can be 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 the drawings.
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 structural view of the combination of an AlN layer and an aluminum domain layer of example 1 of the present invention;
wherein, 1, AlN layer, 1.1, cone, 1.2, cone cavity, 2, aluminum area layer.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the embodiments given herein are intended to be within the scope of the present invention.
Example 1:
referring to fig. 1, a method for manufacturing an LED epitaxial wafer with improved brightness is provided, where an AlN layer of the LED epitaxial wafer is provided with a raised cone, an aluminum region layer, and a recessed and inverted conical cavity, which are sequentially and cyclically arranged, and the raised cone, the aluminum region layer, and the recessed and inverted conical cavity are not connected to each other, and the cone, the aluminum region layer, and the conical cavity are arranged in sequence only to emphasize the sequential position relationship when the three are arranged, and are not limited to start or end with the cone or the aluminum region layer or the conical cavity at the edge of the LED epitaxial wafer;
the manufacturing method comprises the following steps of,
step 3, manufacturing a plurality of convex cones 1.1 on the AlN layer 1 at intervals;
step 4, a plurality of concave and inverted conical cavities 1.2 are manufactured on the AlN layer 1 at intervals, the conical cavities 1.2 and the cones 1.1 are arranged in a staggered mode and are not connected in pairs, namely, one cone 1.1 is arranged between any two adjacent conical cavities 1.2, and one conical cavity 1.2 is arranged between any two adjacent cones 1.1;
step 5, manufacturing a plurality of aluminum area layers 2 on the AlN layer at intervals, wherein each aluminum area layer 2 is adjacent to the conical cavity 1.2 and/or the cone 1.1;
and 6, periodically growing a plurality of multi-quantum well light emitting layers on the AlN layer 1, wherein each multi-quantum well light emitting layer comprises an InGaN well layer and a GaN barrier layer which are sequentially grown, the multi-quantum well light emitting layer grown in the first period is used for filling the conical cavity 1.2 in the step 4, and the multi-quantum well light emitting layers grown in the later period are all positioned on the whole structure comprising the AlN layer 1, the aluminum region layer 2 and the multi-quantum well light emitting layer grown in the previous period from the second period.
In the step 3, the diameter D1 of the bottom surface of the cone 1.1 is 1050nm, the height H1 is 875nm, and the shortest distance D1 between the bottom surfaces of the adjacent cones 1.1 is 2150 nm. The design of the 1.1 parameter of the cone can effectively utilize the InGaN well layer to be more difficult to nucleate on the 1.1 parameter of the cone to reduce the unintentional growth of the InGaN well layer on the 1.1 side wall of the cone, the crystallization quality of the LED epitaxial wafer is improved, and the luminous brightness of the LED epitaxial wafer is improved.
In the step 4, the diameter D2 of the top surface of the conical cavity 1.2 is 850nm, the height H2 is 875nm, and the shortest distance D2 between the top surface of the conical cavity 1.2 and the bottom surface of the adjacent cone 1.1 is 550 nm. The design of the parameters of the conical cavity 1.2 can promote the formation of hundreds of meV (megaelectron volts) potential barriers around the conical cavity 1.2, effectively avoid the capture of carriers by dislocation in a multi-quantum well layer above the conical cavity 1.2, and further improve the luminous efficiency of the LED epitaxial wafer.
In the step 6, the layer thickness D3 of the InGaN well layer grown in the first period is equal to the layer thickness D4 of the GaN barrier layer grown in the first period, and D3+ D4 is H2.
In the step 5, the distance between each aluminum area layer and the adjacent conical cavity is equal to the distance between the aluminum area layer and the adjacent cone, the length and the width of the aluminum area layer are equal to 410mm, and the thickness of the aluminum area layer is 70 nm.
In the step 6, the number of growth cycles of the multiple quantum well light-emitting layer is 7, from the second cycle, in a single growth cycle, the layer thickness of the InGaN well layer is 4nm, and the layer thickness of the GaN barrier layer is 9nm, so that the whole multiple quantum well light-emitting layer can accommodate more carriers, the inclination of energy bands can be reduced, the overlapping of electron hole wave functions can be promoted, the radiative recombination probability of electrons and holes can be increased, and the light-emitting efficiency can be improved.
The manufacturing method of the cone 1.1 in the step 3 is as follows: firstly, coating photoresist on the AlN layer 1, then exposing the photoresist in the non-cone 1.1 manufacturing area on the AlN layer 1 by adopting a stepping photoetching machine and developing the photoresist by adopting a developing machine, then manufacturing a cone 1.1 at a corresponding position by dry etching through an inductively coupled plasma etching machine, and finally cleaning the residual colloid on the AlN layer 1.
The manufacturing method of the conical cavity 1.2 in the step 4 is as follows: firstly, coating photoresist on the AlN layer 1, then carrying out exposure and developing treatment on the photoresist in a non-conical cavity 1.2 manufacturing area on the AlN layer 1 by using a stepping photoetching machine, then carrying out dry etching on the photoresist in a corresponding position by using an inductively coupled plasma etching machine to manufacture a conical cavity 1.2, and finally cleaning the residual colloid on the AlN layer 1.
The manufacturing method of the aluminum area layer in the step 5 is as follows: firstly growing an aluminum layer on the AlN layer by a magnetron sputtering method, then coating photoresist on the aluminum layer, carrying out exposure and development treatment on the photoresist in a non-aluminum region layer manufacturing region on the aluminum layer, then carrying out dry etching on the aluminum layer by an inductively coupled plasma etching machine to manufacture an aluminum region layer at a corresponding position, and finally cleaning the aluminum region layer and residual colloid on the AlN layer.
Before the step 3, the following steps are also included:
step 1, manufacturing a patterned substrate;
step 2, growing a buffer layer GaN, a non-doped GaN layer, a Si-doped N-type GaN layer and an AlN layer 1 on the patterned substrate in sequence, wherein the AlN layer is 1900nm thick;
step 7 is further included after the step 6, and the step 7 is to sequentially grow an electron blocking layer and a P-type semiconductor layer on the multiple quantum well light-emitting layer in the step 6 to prepare an LED epitaxial wafer;
and 2, during operation, performing deposition operation by adopting a metal organic compound chemical vapor deposition method along a direction vertical to the surface of the patterned substrate.
Example 2:
in contrast to example 1, D1 was 1000nm in step 3, the height H1 was 850nm, the shortest distance D1 between the base surfaces of adjacent cones 1.1 was 2100nm, D2 was 800nm in step 4, the height H2 was 850nm, the shortest distance D2 between the top surface of the cone cavity 1.2 and the base surface of the adjacent cone 1.1 was 500nm, and the thickness of the AlN layer 1 was 1800 nm.
Example 3:
in contrast to example 1, D1 was 1100nm in step 3, the height H1 was 900nm, the shortest distance D1 between the base surfaces of adjacent cones 1.1 was 2200nm, D2 was 900nm in step 4, the height H2 was 900nm, the shortest distance D2 between the top surface of the cone cavity 1.2 and the base surface of the adjacent cone 1.1 was 600nm, and the thickness of the AlN layer 1 was 2000 nm.
Example 4:
unlike example 1, the number of growth cycles of the multiple quantum well light emitting layer was 2 in step 6, the layer thickness of the InGaN well layer grown in the second cycle was 3nm, and the layer thickness of the GaN barrier layer grown in the second cycle was 8 nm.
Example 5:
unlike example 1, the number of growth cycles of the multiple quantum well light emitting layer in step 6 was 12, and from the second cycle, the layer thickness of the InGaN well layer was 5nm for each growth cycle, and the layer thickness of the GaN barrier layer was 10nm for each growth cycle.
Example 6:
in contrast to example 1, in step 5 the aluminum field layer 2 had a side length of 400mm and a thickness of 60 nm.
Example 7:
in contrast to example 1, in step 5 the aluminum field layer 2 had a side length of 420mm and a thickness of 80 nm.
Comparative example 1:
unlike example 1, step 3 was not provided.
Comparative example 2:
unlike example 1, step 4 was not provided.
Comparative example 3:
unlike example 1, the order of growth of the InGaN well layer and the GaN barrier layer in the multiple quantum well light emitting layer in step 6 was reversed, i.e., the GaN barrier layer was grown first and the InGaN well layer was grown again in each cycle.
Comparative example 4:
in contrast to example 2, D1 was 950nm in step 3, height H1 was 800nm, spacing D1 between adjacent cones 1.1 was 2050nm, D2 was 750nm in step 4, height H2 was 800nm, spacing D2 between the cone cavity 1.2 and the adjacent cones 1.1 was 450nm, and the AlN layer 1 had a thickness of 1750 nm.
Comparative example 5:
in contrast to example 3, D1 was 1150nm, height H1 was 950nm, shortest distance D1 between the base surfaces of adjacent cones 1.1 was 2250nm in step 3, D2 was 950nm, height H2 was 950nm in step 4, shortest distance D2 between the top surface of the cone cavity 1.2 and the base surface of the adjacent cone 1.1 was 650nm, and the thickness of the AlN layer 1 was 2050 nm.
Comparative example 6:
unlike example 1, the thickness of the multiple quantum well light emitting layer grown in the first period in step 6 was 700 nm.
Comparative example 7:
unlike example 1, the thickness of the multiple quantum well light emitting layer grown in the first period in step 6 was 1000 nm.
Comparative example 8:
in contrast to example 1, in step 4, the height H2 > H1 and H2 were 900 nm.
Comparative example 9:
in contrast to example 1, in step 4 the height H2 < H1 and H2 were 850 nm.
Comparative example 10:
unlike example 5, the InGaN well layer was 6nm in thickness and the GaN barrier layer was 11nm in thickness for each growth cycle from the second cycle.
Comparative example 11:
unlike example 5, the InGaN well layer was 2nm thick and the GaN barrier layer was 7nm thick for each growth cycle from the second cycle.
Comparative example 12:
in contrast to example 1, in step 5 the side length of the aluminum field layer 2 was 390 mm.
Comparative example 13:
in contrast to example 1, in step 5 the side length of the aluminum field layer 2 is 430 mm.
Comparative example 14:
in contrast to example 1, in step 5 the aluminum area layer is an equilateral triangle with a side length of 420mm and a thickness of 80 nm.
Comparative example 15:
unlike example 1, step 5 was not provided.
The LED epitaxial wafers manufactured by the methods for manufacturing LED epitaxial wafers with improved brightness described in examples 1 to 7 and comparative examples 1 to 15 were all randomly sampled to perform the following optoelectronic performance experiments, and the experimental results are shown in table 1, wherein the experimental procedures are as follows:
all samples were plated with an ITO layer of about 150nm under the same pre-process conditions, a Cr/Pt/Au electrode of about 1500nm under the same conditions, and a protective layer of SiO under the same conditions2About 100nm, all samples were then ground and cut under the same conditions into 635 μm by 635 μm (25mil by 25mil) chip particles, and then the samples were individually picked at the same positions to obtain 100 dies, and packaged into white LEDs under the same packaging process. The photoelectric performance of the sample was tested using an integrating sphere at a drive current of 350 mA.
TABLE 1 average of the results of the photoelectric property tests of 100 samples from examples 1 to 7 and comparative examples 1 to 15
As is clear from the data in table 1, the average of the results of the photoelectric property tests of 100 samples obtained in examples 1 to 7 is good, and example 5 is preferable because the number of carriers can be increased by appropriately increasing the number of growth cycles of the multiple quantum well light-emitting layer, and the luminance of the LED epitaxial wafer can be improved. The average of the results of the photoelectric property tests of 100 samples prepared in comparative examples 1-2 was the worst, mainly because comparative example 1 did not have the growth step of the cone 1.1, and comparative example 2 did not have the growth step of the cone cavity 1.2. The average condition of the photoelectric performance experiment results of the 100 samples prepared in the comparative example 3 is poor, and the main reason is that the lattice mismatch degree between the GaN barrier layer and the AlN layer is larger than that between the InGaN well layer and the AlN layer, and the GaN barrier layer grown first generates larger stress, so that an electric field (piezoelectric effect) is formed in the quantum well range, and thus an energy band in the multiple quantum well light-emitting layer is affected, the energy band is bent, and the bending of the energy band can cause the shift of the light-emitting wavelength, thereby causing the average condition of the photoelectric performance experiment results of the LED epitaxial wafer prepared in the comparative example 3 to be poor. The average of the results of the photoelectric property tests of the 100 samples prepared in comparative examples 4 to 13 was inferior to that of examples 1 to 7 of the present invention, mainly because the ranges of the values of D1, H1, D1, D2, D2, the AlN layer thickness, the thickness of the multi-quantum well light-emitting layer grown in the first cycle, the layer thickness of the InGaN well layer grown in each cycle, the layer thickness of the GaN barrier layer grown in each cycle, and the side length of the aluminum region layer 2 were outside the ranges protected by the present invention, resulting in the average of the results of the photoelectric property tests of the LED epitaxial wafers prepared in comparative examples 4 to 13 being inferior to that of examples 1 to 7 of the present invention. The average of the photoelectric property experimental results of the LED epitaxial wafer prepared in comparative example 14 is slightly worse than those of examples 1 to 7 of the present invention, mainly because the aluminum region layer provided in comparative example 14 is an equilateral triangle, which cannot effectively block dislocation defects in the conical cavity from extending to the cone when the multiple quantum well light emitting layer starts to grow from the second period. Comparative example 15 does not have the step of growing the aluminum domain layer 2, and the average of the experimental results of various photoelectric properties of the prepared LED epitaxial wafer is significantly inferior to that of examples 1 to 7 of the present invention.
The principle of the better average of the results of the photoelectric property tests of 100 samples prepared in examples 1-7 of the present invention is explained as follows:
(1) by manufacturing the cones and the conical cavities on the AlN layer at intervals in the steps 3 and 4, the luminous efficiency, namely the brightness, of the LED epitaxial wafer can be improved, the antistatic capacity of the LED epitaxial wafer can be improved, and the wavelength concentration of the LED epitaxial wafer is improved, namely the wavelength uniformity is improved.
(2) And 6, growing multiple-quantum-well light-emitting layers with multiple periods on the AlN layer, so that holes in the multiple-quantum-well light-emitting layers are easily injected into deeper multiple-quantum-well light-emitting layers through the side walls of the conical cavities, the working voltage of the LED epitaxial wafer can be reduced, and the spatial uneven distribution of electrons and holes can be improved. In addition, the cone can release the mismatch stress In the multiple quantum well light emitting layer, so that more In components can be incorporated, the growth of the long-wavelength InGaN yellow-green light quantum well layer is very favorable, the same wavelength can be obtained more easily, the wavelength concentration of the LED epitaxial wafer is improved, the growth temperature of the InGaN quantum well is improved more easily, the crystal quality of the grown LED epitaxial wafer is better, and the photoelectric performance of the LED epitaxial wafer is better. The multiple quantum well luminescent layer grown In the first period In the step 6 just fills the conical cavity, so that crystal defects such as In-rich clusters and the like In the conical cavity can be effectively removed, the crystal quality of the multiple quantum well luminescent layer In the conical cavity region is improved, non-radiative recombination is inhibited to a certain extent, and the luminous efficiency of the multiple quantum well luminescent layer is enhanced.
(3) The design of the cone in the step 3 is beneficial to releasing the stress in the LED epitaxial wafer by the atoms in the multi-quantum well light-emitting layer, the atoms are uniformly filled upwards, and the uniformity of the atoms in the LED epitaxial wafer can be improved. The design of the conical cavity in the step 4 is beneficial to blocking the upward extension of the defects when the multiple quantum well light-emitting layer is directly pushed upwards in parallel, the dislocation density is reduced, and the crystal quality of the LED epitaxial wafer is improved. The combination of the step 3, the step 4 and the step 6 can improve the brightness of the LED epitaxial wafer, enhance the antistatic capability, improve the concentration ratio of the wavelength and reduce the forward voltage of the LED epitaxial wafer.
(4) Manufacturing a plurality of aluminum area layers on the AlN layer at intervals, wherein on one hand, the aluminum area layers reflect a part of light emitted downwards from the light emitting layer of the multiple quantum wells by virtue of good light reflectivity of the aluminum area layers, so that the brightness of the LED epitaxial wafer is improved; on the other hand, the aluminum region layer can further prevent dislocation defects in the conical cavity from extending to the cone when the multiple quantum well light-emitting layer starts to grow from the second period, and lateral growth of the multiple quantum well light-emitting layer on the cone can be reduced, so that the crystal quality of the multiple quantum well light-emitting layer can be improved, the light-emitting efficiency and the antistatic capacity of the LED epitaxial wafer can be improved, and the concentration of wavelengths can be improved.
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. A manufacturing method of an LED epitaxial wafer for improving brightness is characterized in that a raised cone, an aluminum region layer and a sunken and inverted cone cavity which are sequentially and circularly arranged are arranged on an AlN layer of the LED epitaxial wafer, and are not connected with each other;
the manufacturing method comprises the following steps of,
step 3, manufacturing a plurality of convex cones on the AlN layer at intervals;
step 4, manufacturing a plurality of concave and inverted conical cavities on the AlN layer at intervals, wherein the conical cavities and the cones are arranged in a staggered mode and are not connected in pairs;
step 5, manufacturing a plurality of aluminum area layers on the AlN layer at intervals, wherein each aluminum area layer is adjacent to the conical cavity and/or the cone;
and 6, periodically growing a plurality of multi-quantum well light emitting layers on the AlN layer, wherein each multi-quantum well light emitting layer comprises an InGaN well layer and a GaN barrier layer which are sequentially grown, the multi-quantum well light emitting layer grown in the first period is used for filling the conical cavity in the step 4, and the multi-quantum well light emitting layers grown in the later period are all located on the whole structure comprising the AlN layer, the aluminum region layer and the multi-quantum well light emitting layer grown in the previous period from the second period.
2. The method as claimed in claim 1, wherein in the step 3, the diameter D1 of the bottom surface of the cone is 1000-1100nm, the height H1 is 850-900nm, and the shortest distance D1 between the bottom surfaces of adjacent cones is 2100-2200 nm.
3. The method as claimed in claim 2, wherein in the step 4, the diameter D2 of the top surface of the conical cavity is 800-900nm, the height H2 is 850-900nm, H2-H1, and the shortest distance D2 between the top surface of the conical cavity and the bottom surface of the adjacent cone is 500-600 nm.
4. The method according to claim 3, wherein in step 6, the layer thickness D3 of the InGaN well layer grown in the first period is equal to the layer thickness D4 of the GaN barrier layer grown in the first period, and D3+ D4 is H2.
5. The method as claimed in claim 4, wherein in the step 5, the distance between each aluminum region layer and the adjacent conical cavity is equal to the distance between the aluminum region layer and the adjacent conical cavity, the length and width of the aluminum region layer are equal to 400-420mm, and the thickness of the aluminum region layer is 60-80 nm.
6. The method according to claim 5, wherein in the step 6, the number of growth cycles of the multiple quantum well light emitting layer is 2 to 12, and from the second period, in a single growth cycle, the layer thickness of the InGaN well layer is 3 to 5nm, and the layer thickness of the GaN barrier layer is 8 to 10 nm.
7. The method of any one of claims 1 to 6, wherein the method of forming the cone in step 3 is as follows: the method comprises the steps of firstly coating photoresist on an AlN layer, then carrying out exposure and development treatment on the photoresist in a non-cone manufacturing area on the AlN layer, then manufacturing a cone at a corresponding position through dry etching, and finally cleaning residual colloid on the AlN layer.
8. The method for manufacturing the conical cavity in the step 4 is characterized in that the method for manufacturing the conical cavity in the step 4 comprises the following steps: the method comprises the steps of firstly coating photoresist on an AlN layer, then carrying out exposure and development treatment on the photoresist in a non-conical cavity manufacturing area on the AlN layer, then manufacturing a conical cavity at a corresponding position through dry etching, and finally cleaning residual colloid on the AlN layer.
9. The method of claim 8, wherein the aluminum region layer in step 5 is formed by: firstly growing an aluminum layer on the AlN layer by a magnetron sputtering method, then coating photoresist on the aluminum layer, carrying out exposure and development treatment on the photoresist in a non-aluminum region layer manufacturing region on the aluminum layer, then manufacturing an aluminum region layer at a corresponding position by dry etching, and finally cleaning the aluminum region layer and residual colloid on the AlN layer.
10. The method of manufacturing according to claim 9, further comprising, before the step 3, the steps of:
step 1, manufacturing a patterned substrate;
step 2, growing a buffer layer GaN, a non-doped GaN layer, a Si-doped N-type GaN layer and an AlN layer on the patterned substrate in sequence, wherein the thickness of the AlN layer is 1800-2000 nm;
step 7 is further included after the step 6, and the step 7 is to sequentially grow an electron blocking layer and a P-type semiconductor layer on the multiple quantum well light-emitting layer in the step 6 to prepare an LED epitaxial wafer;
and 2, during operation, performing deposition operation by adopting a metal organic compound chemical vapor deposition method along a direction vertical to the surface of the patterned substrate.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1447990A (en) * | 2000-07-18 | 2003-10-08 | 索尼株式会社 | Semiconductor light-emitting device and method for mfg. semiconductor light-emitting device |
| CN101024903A (en) * | 2006-02-17 | 2007-08-29 | 住友电气工业株式会社 | Gallium nitride crystal substrate and method of producing same |
| CN101621099A (en) * | 2008-07-01 | 2010-01-06 | 台湾积体电路制造股份有限公司 | Circuit structure |
| US8294163B2 (en) * | 2010-02-01 | 2012-10-23 | Hermes-Epitek Corp. | Optoelectronic component with three-dimension quantum well structure and method for producing the same |
| US8674383B2 (en) * | 2010-01-21 | 2014-03-18 | Siphoton Inc. | Solid state lighting device on a conductive substrate |
| CN109103307A (en) * | 2018-08-17 | 2018-12-28 | 开发晶照明（厦门）有限公司 | Light-emitting component and its manufacturing method |
| CN109360871A (en) * | 2018-08-08 | 2019-02-19 | 华灿光电（浙江）有限公司 | A kind of patterned substrate, LED epitaxial slice and preparation method thereof |
-
2021
- 2021-03-31 CN CN202110347563.8A patent/CN113097350B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1447990A (en) * | 2000-07-18 | 2003-10-08 | 索尼株式会社 | Semiconductor light-emitting device and method for mfg. semiconductor light-emitting device |
| CN101024903A (en) * | 2006-02-17 | 2007-08-29 | 住友电气工业株式会社 | Gallium nitride crystal substrate and method of producing same |
| CN101621099A (en) * | 2008-07-01 | 2010-01-06 | 台湾积体电路制造股份有限公司 | Circuit structure |
| US8674383B2 (en) * | 2010-01-21 | 2014-03-18 | Siphoton Inc. | Solid state lighting device on a conductive substrate |
| US8294163B2 (en) * | 2010-02-01 | 2012-10-23 | Hermes-Epitek Corp. | Optoelectronic component with three-dimension quantum well structure and method for producing the same |
| CN109360871A (en) * | 2018-08-08 | 2019-02-19 | 华灿光电（浙江）有限公司 | A kind of patterned substrate, LED epitaxial slice and preparation method thereof |
| CN109103307A (en) * | 2018-08-17 | 2018-12-28 | 开发晶照明（厦门）有限公司 | Light-emitting component and its manufacturing method |
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