CN109273568B

CN109273568B - Gallium nitride-based light emitting diode epitaxial wafer and manufacturing method thereof

Info

Publication number: CN109273568B
Application number: CN201810961491.4A
Authority: CN
Inventors: 葛永晖; 郭炳磊; 王群; 吕蒙普; 胡加辉; 李鹏
Original assignee: HC Semitek Zhejiang Co Ltd
Current assignee: HC Semitek Zhejiang Co Ltd
Priority date: 2018-08-22
Filing date: 2018-08-22
Publication date: 2020-04-14
Anticipated expiration: 2038-08-22
Also published as: CN109273568A

Abstract

The invention discloses a gallium nitride-based light emitting diode epitaxial wafer and a manufacturing method thereof, belonging to the technical field of semiconductors. The manufacturing method comprises the following steps: providing a substrate and placing the substrate in the reaction chamber; sequentially growing an N-type semiconductor layer and an active layer on a substrate; discontinuously growing an electron blocking layer on the active layer; wherein the discontinuous growth comprises a plurality of growth cycles occurring in sequence, each growth cycle comprising a growth phase and a treatment phase occurring after the growth phase; in the growth stage, all reactants for growing the electron blocking layer are continuously introduced into the reaction cavity to grow the electron blocking layer; stopping introducing part or all of reactants for growing the electron blocking layer into the reaction cavity during the treatment stage, and continuously introducing hydrogen into the reaction cavity to remove the reactants remaining on the surface of the electron blocking layer; and growing a P-type semiconductor layer on the electron blocking layer. The invention makes the interface between the electron barrier layer and the P-type semiconductor layer clear and improves the overall crystal quality of the epitaxial wafer.

Description

Gallium nitride-based light emitting diode epitaxial wafer and manufacturing method thereof

Technical Field

The invention relates to the technical field of semiconductors, in particular to a gallium nitride-based light emitting diode epitaxial wafer and a manufacturing method thereof.

Background

A Light Emitting Diode (LED) is a semiconductor electronic component capable of Emitting Light. The LED has received much attention because of its advantages of energy saving, environmental protection, high reliability, long service life, etc., and in recent years, it has been widely used in the fields of background light sources and display screens, and has started to advance to the civil illumination market. Since the civil lighting focuses on the power saving, energy saving and service life of the product, it is very critical to reduce the series resistance of the LED and improve the antistatic capability of the LED.

The epitaxial wafer is a primary finished product in the LED preparation process. The conventional LED epitaxial wafer includes a substrate, an N-type semiconductor layer, an active layer, and a P-type semiconductor layer, which are sequentially stacked on the substrate. The P-type semiconductor layer is used for providing holes for carrying out compound luminescence, the N-type semiconductor layer is used for providing electrons for carrying out compound luminescence, the active layer is used for carrying out radiation compound luminescence of the electrons and the holes, and the substrate is used for providing a growth surface for the epitaxial material.

The number of electrons provided by the N-type semiconductor layer is much greater than the number of holes of the P-type semiconductor layer, plus the volume of electrons is much smaller than the volume of holes, resulting in the number of electrons injected into the active layer being much greater than the number of holes. In order to avoid the electrons provided by the N-type semiconductor layer from migrating into the P-type semiconductor layer and non-radiatively recombining with the holes, an electron blocking layer is generally disposed between the active layer and the P-type semiconductor layer, which can block the electrons from migrating from the active layer to the P-type semiconductor layer.

In the process of implementing the invention, the inventor finds that the prior art has at least the following problems:

the N-type semiconductor layer is made of N-type doped (such as silicon) gallium nitride, and the P-type semiconductor layer is made of P-type doped (such as magnesium) gallium nitride; the active layer comprises a plurality of quantum wells and a plurality of quantum barriers which are alternately stacked, the quantum wells are made of gallium nitride doped with indium element, and the quantum barriers are made of undoped gallium nitride; the electron blocking layer is made of P-type doped aluminum gallium nitride; namely, the N-type semiconductor layer, the active layer and the P-type semiconductor layer are gallium nitride layers doped with different elements. Because of different doping elements, two adjacent gallium nitride layers have interfaces with each other. There is diffusion of the doping element at the interface, generally in the same direction as the epitaxial growth, i.e. the doping element in the previously grown gallium nitride layer diffuses into the subsequently grown gallium nitride layer. The diffusion of the doping elements can cause the unclear interface, easily generate defects and cause adverse effects on the growth quality of the epitaxial wafer.

Taking the interface between the electron blocking layer and the P-type semiconductor layer as an example, the P-type semiconductor layer grows on the electron blocking layer, so that aluminum doped in the electron blocking layer can diffuse into the active layer, the interface between the electron blocking layer and the P-type semiconductor layer is unclear, and the interface between the electron blocking layer and the P-type semiconductor layer is easy to generate defects, which affect the injection of holes provided by the P-type semiconductor layer into the active layer for compound light emission, and finally reduce the light emitting efficiency of the LED.

Disclosure of Invention

The embodiment of the invention provides a gallium nitride-based light-emitting diode epitaxial wafer and a manufacturing method thereof, which can solve the problem that the luminous efficiency of an LED is influenced by the unclear interface between an electronic barrier layer and a P-type semiconductor layer in the prior art. The technical scheme is as follows:

in one aspect, an embodiment of the present invention provides a method for manufacturing a gallium nitride-based light emitting diode epitaxial wafer, where the method for manufacturing the gallium nitride-based light emitting diode epitaxial wafer includes:

providing a substrate and placing the substrate in a reaction chamber;

sequentially growing an N-type semiconductor layer and an active layer on the substrate;

discontinuously growing an electron blocking layer on the active layer; wherein the discontinuous growth comprises a plurality of growth cycles occurring in sequence, each growth cycle comprising a growth phase and a treatment phase occurring after the growth phase; in the growth stage, all reactants for growing the electron blocking layer are continuously introduced into the reaction cavity to grow the electron blocking layer; stopping introducing part or all of reactants for growing the electron blocking layer into the reaction cavity during the treatment stage, and continuously introducing hydrogen into the reaction cavity to remove the reactants remaining on the surface of the electron blocking layer;

and growing a P-type semiconductor layer on the electron blocking layer.

Optionally, in the growth stage, continuously introducing all reactants for growing the electron blocking layer into the reaction chamber, and growing the electron blocking layer includes:

and continuously introducing an aluminum source, a gallium source, ammonia gas and a P-type dopant into the reaction cavity to form a P-type doped aluminum gallium nitride layer.

In a possible implementation manner of the embodiment of the present invention, in the processing stage, stopping introducing part or all of the reactant for growing the electron blocking layer into the reaction chamber, and continuously introducing hydrogen into the reaction chamber to remove the reactant remaining on the surface of the electron blocking layer includes:

and stopping introducing an aluminum source, a gallium source and a P-type dopant into the reaction cavity, continuously introducing ammonia gas into the reaction cavity, and continuously introducing hydrogen gas into the reaction cavity at the same time, so as to remove the aluminum source remained on the surface of the P-type doped aluminum gallium nitride layer.

In another possible implementation manner of the embodiment of the present invention, in the processing stage, stopping introducing part or all of the reactant for growing the electron blocking layer into the reaction chamber, and continuously introducing hydrogen into the reaction chamber to remove the reactant remaining on the surface of the electron blocking layer includes:

and stopping introducing an aluminum source, ammonia gas and a P-type dopant into the reaction cavity, continuously introducing a gallium source into the reaction cavity, and simultaneously continuously introducing hydrogen into the reaction cavity to remove the residual aluminum source on the surface of the P-type doped aluminum gallium nitride layer.

In another possible implementation manner of the embodiment of the present invention, during the processing stage, stopping introducing part or all of the reactant for growing the electron blocking layer into the reaction chamber, and continuously introducing hydrogen into the reaction chamber to remove the reactant remaining on the surface of the electron blocking layer, includes:

stopping introducing an aluminum source, a gallium source, ammonia gas and a P-type dopant into the reaction cavity, and continuously introducing hydrogen gas into the reaction cavity to remove the aluminum source remained on the surface of the P-type doped aluminum gallium nitride layer.

Preferably, the introducing flow rate of the aluminum source is 20sccm to 500sccm, the introducing flow rate of the gallium source is 200sccm to 900sccm, the introducing flow rate of the ammonia gas is 5L/min to 50L/min, and the introducing flow rate of the P-type dopant is 50sccm to 800 sccm.

More preferably, the flow rate of the introduced hydrogen is 5L/min to 100L/min.

Further, the duration of the treatment phase is 5s to 15 s.

Optionally, the growing the P-type semiconductor layer on the electron blocking layer includes:

and discontinuously growing a P-type semiconductor layer on the electron blocking layer.

On the other hand, the embodiment of the invention provides a gallium nitride-based light emitting diode epitaxial wafer, which comprises a substrate, an N-type semiconductor layer, an active layer, an electron blocking layer and a P-type semiconductor layer, wherein the N-type semiconductor layer, the active layer, the electron blocking layer and the P-type semiconductor layer are sequentially stacked on the substrate, the electron blocking layer comprises a plurality of sequentially stacked sub-layers, and the surface of each sub-layer is a surface treated by hydrogen.

The technical scheme provided by the embodiment of the invention has the following beneficial effects:

the electron barrier layer is grown discontinuously by adopting a plurality of growth periods which appear in sequence, each growth period comprises a growth stage and a treatment stage, and all reactants for growing the electron barrier layer are continuously introduced into the reaction cavity during the growth stage, so that the electron barrier layer can be grown; and stopping introducing part or all of reactants for growing the electron blocking layer into the reaction cavity in a treatment stage after the growth stage, and continuously introducing hydrogen into the reaction cavity, so that the growth of the electron blocking layer can be stopped, atoms can obtain a longer free path, the reactants remained on the surface of the electron blocking layer can be removed as soon as possible, only formed crystals are left on the surface of the electron blocking layer, the unreacted reactants are prevented from being diffused into the subsequently grown crystals, the interface between the electron blocking layer and the P-type semiconductor layer is clear, the defects generated by the interface are reduced, the integral crystal quality of the epitaxial wafer is improved, the mobility of holes is improved, the recombination efficiency of the holes and electrons in the active layer is increased, and the luminous efficiency of the LED is finally improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a flowchart of a method for manufacturing an epitaxial wafer of a gallium nitride-based light emitting diode according to an embodiment of the present invention;

FIG. 2 is a schematic diagram illustrating a variation of the flow of gases introduced into the reaction chamber during the growth of the electron blocking layer according to an embodiment of the present invention;

FIG. 3 is a schematic diagram illustrating another variation of the flow rates of gases introduced into the reaction chamber during the growth of the electron blocking layer according to an embodiment of the present invention;

FIG. 4 is a schematic diagram illustrating another variation of the flow rates of gases introduced into the reaction chamber during the growth of the electron blocking layer according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of an epitaxial wafer of a gallium nitride-based light emitting diode according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiment of the invention provides a gallium nitride-based light emitting diode epitaxial wafer. Fig. 1 is a flowchart of a method for manufacturing an epitaxial wafer of a gallium nitride-based light emitting diode according to an embodiment of the present invention. Referring to fig. 1, the manufacturing method includes:

step 101: a substrate is provided and placed in the reaction chamber.

Specifically, the material of the substrate may be sapphire (aluminum oxide is a main material), such as sapphire having a crystal orientation of [0001 ].

Optionally, after step 101, the manufacturing method may further include:

controlling the temperature to be 1000-1200 ℃ (preferably 1100 ℃), and annealing the substrate for 1-10 minutes (preferably 5 minutes) in a hydrogen atmosphere;

the substrate is subjected to a nitridation process.

The surface of the substrate is cleaned through the steps, impurities are prevented from being doped into the epitaxial wafer, and the growth quality of the epitaxial wafer is improved.

Step 102: an N-type semiconductor layer and an active layer are sequentially grown on a substrate.

Specifically, the material of the N-type semiconductor layer may be N-type doped (e.g., silicon) gallium nitride. The active layer may include a plurality of quantum wells and a plurality of quantum barriers, which are alternately stacked; the quantum well material may be indium gallium nitride (InGaN), such as In_xGa_1-xN, 0 < x < 1, and gallium nitride can be used as the material of the quantum barrier.

Further, the thickness of the N-type semiconductor layer may be 1 μm to 3 μm, preferably 2 μm; the doping concentration of the N-type dopant in the N-type semiconductor layer may be 10¹⁸/cm³～3*10¹⁹/cm³Preferably 6 x 10¹⁸/cm³. The thickness of the quantum well can be 3nm to 4nm, and is preferably 3.5 nm; the thickness of the quantum barrier can be 9 nm-20 nm, preferably 15 nm; the number of quantum wells is the same as the number of quantum barriers, and the number of quantum barriers may be 5 to 11, preferably 8.

Specifically, this step 102 may include:

an N-type semiconductor layer is grown on a substrate under a temperature of 1000 to 1100 deg.C (preferably 1050 deg.C) and a pressure of 100to 500torr (preferably 300 torr).

Growing an active layer on the N-type semiconductor layer; wherein the growth temperature of the quantum well is 720 ℃ to 829 ℃ (preferably 760 ℃), and the pressure is 100torr to 500torr (preferably 300 torr); the growth temperature of the quantum barrier is 850 to 959 deg.C (preferably 900 deg.C), and the pressure is 100to 500torr (preferably 300 torr).

Optionally, before step 102, the manufacturing method may further include:

a buffer layer is grown on a substrate.

Relieving stress and defect generated by lattice mismatch between substrate material and gallium nitride through buffer layer, and providing nucleation center for epitaxial growth of gallium nitride material

Accordingly, an N-type semiconductor layer is grown on the buffer layer.

Specifically, gallium nitride may be used as a material of the buffer layer.

Further, the thickness of the buffer layer may be 15nm to 40nm, preferably 25 nm.

Specifically, growing a buffer layer on a substrate may include:

controlling the temperature to be 400-600 ℃ (preferably 500 ℃), and the pressure to be 400-600 torr (preferably 500torr), and growing a buffer layer on the substrate;

the buffer layer is subjected to in-situ annealing treatment for 5 to 10 minutes (preferably 8 minutes) at a controlled temperature of 1000 to 1200 c (preferably 1100 c) and a pressure of 400to 600torr (preferably 500 torr).

Preferably, after growing the buffer layer on the substrate, the manufacturing method may further include:

and growing an undoped gallium nitride layer on the buffer layer.

Stress and defects generated by lattice mismatch between the substrate material and the gallium nitride are further relieved through the undoped gallium nitride layer, and a growth surface with good crystal quality is provided for the main body structure of the epitaxial wafer.

Accordingly, an N-type semiconductor layer is grown on the undoped gallium nitride layer.

In a specific implementation, the buffer layer is a thin layer of gallium nitride that is first grown at low temperature on the patterned substrate, and is therefore also referred to as a low temperature buffer layer. Then, the longitudinal growth of gallium nitride is carried out on the low-temperature buffer layer, and a plurality of mutually independent three-dimensional island-shaped structures called three-dimensional nucleation layers can be formed; then, transverse growth of gallium nitride is carried out on all the three-dimensional island structures and among the three-dimensional island structures to form a two-dimensional plane structure which is called a two-dimensional recovery layer; and finally, growing a thicker gallium nitride layer called an intrinsic gallium nitride layer on the two-dimensional growth layer at a high temperature. The three-dimensional nucleation layer, two-dimensional recovery layer, and intrinsic gallium nitride layer are collectively referred to as undoped gallium nitride layer in this embodiment.

Further, the thickness of the three-dimensional nucleation layer can be 100nm to 600nm, preferably 350 nm; the thickness of the two-dimensional recovery layer can be 500 nm-800 nm, preferably 650 nm; the thickness of the intrinsic gallium nitride layer may be 800nm to 2 μm, preferably 1.4 μm.

Specifically, growing an undoped gallium nitride layer on the buffer layer may include:

controlling the temperature to be 1000-1100 ℃ (preferably 1050 ℃), and the pressure to be 100-600 torr (preferably 300torr), and growing the three-dimensional nucleation layer on the buffer layer for 10-20 min;

controlling the temperature to be 1000-1200 ℃ (preferably 1100 ℃), the pressure to be 100-500 torr (preferably 300torr), and growing a two-dimensional recovery layer on the three-dimensional nucleation layer for 10-20 min and 20-40 min;

the intrinsic gallium nitride layer is grown on the two-dimensional restoration layer at a controlled temperature of 1000 ℃ to 1200 ℃ (preferably 1100 ℃) and a pressure of 100torr to 500torr (preferably 300 torr).

Optionally, before growing the active layer on the N-type semiconductor layer, the manufacturing method may further include:

and growing a stress release layer on the N-type semiconductor layer.

Stress generated by lattice mismatch between sapphire and gallium nitride is released through the stress release layer, crystal quality of the active layer is improved, radiation composite luminescence of electrons and holes in the active layer is facilitated, internal quantum efficiency of the LED is improved, and luminous efficiency of the LED is improved.

Accordingly, an active layer is grown on the stress relieving layer.

Specifically, the material of the stress release layer can be gallium indium aluminum nitride (AlInGaN), so that the stress generated by lattice mismatch of sapphire and gallium nitride can be effectively released, the crystal quality of an epitaxial wafer is improved, and the luminous efficiency of the LED is improved.

Preferably, the molar content of the aluminum component in the stress release layer may be less than or equal to 0.2, and the molar content of the indium component in the stress release layer may be less than or equal to 0.05, so as to avoid causing adverse effects.

Further, the thickness of the stress release layer may be 50nm to 500nm, preferably 300 nm.

Specifically, growing the stress relief layer on the N-type semiconductor layer may include:

the temperature is controlled to be 800 ℃ to 1100 ℃ (preferably 950 ℃) and the pressure is controlled to be 100torr to 500torr (preferably 300torr), and the stress release layer is grown on the N-type semiconductor layer.

Step 103: and discontinuously growing an electron blocking layer on the active layer.

In this embodiment, the intermittent growth comprises a plurality of growth cycles occurring in sequence, each growth cycle comprising a growth phase and a treatment phase occurring after the growth phase. And in the growth stage, all reactants for growing the electron blocking layer are continuously introduced into the reaction cavity to grow the electron blocking layer. And in the treatment stage, stopping introducing part or all of the reactants for growing the electron blocking layer into the reaction cavity, and continuously introducing hydrogen into the reaction cavity to remove the reactants remaining on the surface of the electron blocking layer.

In the embodiment of the invention, the electron barrier layer is discontinuously grown by adopting a plurality of growth cycles which appear in sequence, each growth cycle comprises a growth stage and a treatment stage, and all reactants for growing the electron barrier layer are continuously introduced into the reaction cavity during the growth stage, so that the electron barrier layer can be grown; and stopping introducing part or all of reactants for growing the electron blocking layer into the reaction cavity in a treatment stage after the growth stage, and continuously introducing hydrogen into the reaction cavity, so that the growth of the electron blocking layer can be stopped, atoms can obtain a longer free path, the reactants remained on the surface of the electron blocking layer can be removed as soon as possible, only formed crystals are left on the surface of the electron blocking layer, the unreacted reactants are prevented from being diffused into the subsequently grown crystals, the interface between the electron blocking layer and the P-type semiconductor layer is clear, the defects generated by the interface are reduced, the integral crystal quality of the epitaxial wafer is improved, the mobility of holes is improved, the recombination efficiency of the holes and electrons in the active layer is increased, and the luminous efficiency of the LED is finally improved. And the treatment stage and the growth stage are alternately generated, so that the aluminum element is uniformly distributed in the electron blocking layer, the influence of the over-high content of the local aluminum element on hole injection into the active layer is avoided, and the luminous efficiency of the LE is reduced.

Specifically, the electron blocking layer may be made of P-type doped aluminum gallium nitride (AlGaN) such as Al_yGa_1-yN，0.1＜y＜0.5。

Optionally, during the growth phase, continuously introducing all reactants for growing the electron blocking layer into the reaction chamber, and growing the electron blocking layer may include:

In an implementation manner of this embodiment, the stopping of introducing part or all of the reactant for growing the electron blocking layer into the reaction chamber during the processing stage, and continuously introducing hydrogen into the reaction chamber to remove the reactant remaining on the surface of the electron blocking layer may include:

stopping introducing the aluminum source, the gallium source and the P-type dopant into the reaction cavity, continuously introducing ammonia gas into the reaction cavity, and continuously introducing hydrogen gas into the reaction cavity at the same time, so as to remove the residual aluminum source on the surface of the P-type doped aluminum gallium nitride layer.

And in the treatment stage, ammonia gas is introduced into the reaction cavity while hydrogen is introduced into the reaction cavity, the ammonia gas can prevent the hydrogen gas from etching the surface of the P-type doped aluminum gallium nitride layer, the formed crystal is prevented from being decomposed, and the surface smoothness of the P-type doped aluminum gallium nitride layer is good. And the ammonia gas is cheap, and the influence on the production cost is negligible.

FIG. 2 is a schematic diagram showing a variation of the flow of gases introduced into the reaction chamber during the growth of the electron blocking layer. Referring to fig. 2, growth phases and treatment phases alternate during the growth of the electron blocking layer. The flow rates of the aluminum source, the gallium source and the P-type dopant during the growth stage are greater than 0, and the flow rates of the aluminum source, the gallium source and the P-type dopant during the treatment stage are 0, namely the aluminum source, the gallium source and the P-type dopant are only introduced into the reaction chamber during the growth stage. The flow of ammonia gas is larger than 0 in the growth stage and the treatment stage, namely the ammonia gas is introduced into the reaction cavity in the growth stage and the treatment stage. The flow of the hydrogen in the growth stage is 0, and the flow of the hydrogen in the treatment stage is more than 0, namely the hydrogen is only introduced into the reaction cavity in the treatment stage.

In another implementation manner of this embodiment, the stopping of introducing part or all of the reactant for growing the electron blocking layer into the reaction chamber during the processing stage, and continuously introducing hydrogen into the reaction chamber to remove the reactant remaining on the surface of the electron blocking layer may include:

stopping introducing the aluminum source, ammonia gas and the P-type dopant into the reaction cavity, continuously introducing the gallium source into the reaction cavity, and simultaneously continuously introducing hydrogen gas into the reaction cavity to remove the residual aluminum source on the surface of the P-type doped aluminum gallium nitride layer.

And in the treatment stage, when hydrogen is introduced into the reaction cavity, a gallium source is introduced into the reaction cavity, the gallium source can prevent the hydrogen from etching the surface of the P-type doped aluminum gallium nitride layer, the formed crystal is prevented from being decomposed, and the surface smoothness of the P-type doped aluminum gallium nitride layer is good.

FIG. 3 is a schematic view of another variation of the flow of gases into the reaction chamber during the growth of the electron blocking layer. Referring to fig. 3, growth phases and treatment phases alternate during the growth of the electron blocking layer. The flow rates of the aluminum source, the ammonia gas and the P-type dopant during the growth stage are greater than 0, and the flow rates of the aluminum source, the ammonia gas and the P-type dopant during the treatment stage are 0, namely the aluminum source, the ammonia gas and the P-type dopant are only introduced into the reaction chamber during the growth stage. The flow of the gallium source is larger than 0 in the growth stage and the treatment stage, namely the gallium source is introduced into the reaction cavity in the growth stage and the treatment stage. The flow of the hydrogen in the growth stage is 0, and the flow of the hydrogen in the treatment stage is more than 0, namely the hydrogen is only introduced into the reaction cavity in the treatment stage.

stopping introducing the aluminum source, the gallium source, the ammonia gas and the P-type dopant into the reaction cavity, and continuously introducing the hydrogen gas into the reaction cavity to remove the aluminum source remained on the surface of the P-type doped aluminum gallium nitride layer.

In the treatment stage, only hydrogen is introduced into the reaction cavity, so that the lowest cost is realized.

FIG. 4 is a schematic diagram of another variation of the flow of gases into the reaction chamber during the growth of the electron blocking layer. Referring to fig. 4, growth phases and treatment phases alternate during the growth of the electron blocking layer. And in the growth stage, the flow rates of the aluminum source, the gallium source, the ammonia gas and the P-type dopant are greater than 0, and in the treatment stage, the flow rates of the aluminum source, the gallium source, the ammonia gas and the P-type dopant are 0, namely the aluminum source, the gallium source, the ammonia gas and the P-type dopant are only introduced into the reaction chamber in the growth stage. The flow of the hydrogen in the growth stage is 0, and the flow of the hydrogen in the treatment stage is more than 0, namely the hydrogen is only introduced into the reaction cavity in the treatment stage.

Optionally, the introduction flow rate of the aluminum source can be 20sccm to 500sccm, preferably 260 sccm; the flow rate of the gallium source can be 200sccm to 900sccm, preferably 550 sccm; the flow rate of the ammonia gas can be 5L/min to 50L/min, preferably 30L/min; the introduction flow rate of the P-type dopant may be 50sccm to 800sccm, preferably 400 sccm.

The doping concentration of the aluminum element and the P-type dopant in the electron blocking layer is within a proper range by matching the introduction flow rates of the aluminum source, the gallium source, the ammonia gas and the P-type dopant.

Further, the content of the aluminum component in the electron blocking layer may be 0.1 to 0.5, preferably 0.3.

If the content of the aluminum component in the electron blocking layer is less than 0.1, the electron cannot be effectively blocked from jumping into the P-type semiconductor layer due to the low content of the aluminum component in the electron blocking layer, so that the LED chip is likely to leak electricity; if the content of the aluminum component in the electron blocking layer is greater than 0.5, it is possible to block injection of holes into the active layer due to the higher content of the aluminum component in the electron blocking layer, reducing the light emitting efficiency of the LED.

Further, the doping concentration of the P-type dopant in the electron blocking layer may be 10¹⁸/cm³～10²⁰/cm³Preferably 10¹⁹/cm³。

If the doping concentration of the P-type dopant in the electron blocking layer is lower than that of the electron blocking layer, hole injection into the active layer may be affected due to the lower doping concentration of the P-type dopant in the electron blocking layer, so that the recombination efficiency of holes and electrons in the active layer is reduced, and finally, the light emitting efficiency of the LED is reduced; if the doping concentration of the P-type dopant in the electron blocking layer is higher than that of the active layer, the crystal quality of the electron blocking layer may be poor due to the higher doping concentration of the P-type dopant in the electron blocking layer, which affects the recombination efficiency of electrons and holes in the active layer, and finally reduces the light emitting efficiency of the LED.

Preferably, the flow rate of hydrogen gas may be 5L/min to 100L/min, preferably 50L/min.

If the introduction flow rate of the hydrogen is less than 5L/min, the residual reactant on the surface of the P-type doped aluminum gallium nitride layer can not be removed quickly due to the fact that the introduction flow rate of the hydrogen is low; if the flow rate of the introduced hydrogen is greater than 100L/min, the surface of the P-type doped aluminum gallium nitride layer may be etched due to the large flow rate of the introduced hydrogen, and the formed gallium nitride crystal may be decomposed, so that the surface of the P-type doped aluminum gallium nitride layer is rough and uneven, and the growth of the subsequent semiconductor layer may be affected.

Further, the duration of the treatment phase may be between 5s and 15s, preferably 10s or 12 s.

If the duration of the treatment phase is less than 5s, the residual reactant on the surface of the P-type doped aluminum gallium nitride layer may not be effectively removed due to the short duration of the treatment phase; if the duration of the treatment stage is longer than 15s, hydrogen may etch the surface of the P-type doped aluminum gallium nitride layer due to the longer duration of the treatment stage, and decompose the formed gallium nitride crystal, so that the surface of the P-type doped aluminum gallium nitride layer is rough and uneven, which affects the growth of the subsequent semiconductor layer.

Alternatively, the duration of the growth phase may be between 10s and 50s, preferably 30 s.

If the duration of the growth phase is less than 10s, the number of growth cycles may be too large due to the short duration of the growth phase, which affects the production efficiency; if the duration of the growth phase is longer than 50s, part of the reactants may not be removed in time due to the long duration of the growth phase, the remaining reactants may diffuse in the electron blocking layer, the aluminum element is not uniformly distributed in the electron blocking layer, the hole injection into the active layer is affected, and the light emitting efficiency of the LED is finally reduced.

Further, the thickness of the P-type doped aluminum gallium nitride layer formed in the growth stage may be 2nm to 9nm, preferably 6 nm.

If the thickness of the P-type doped aluminum gallium nitride layer formed in the growth stage is less than 2nm, the number of growth cycles is too large due to the fact that the P-type doped aluminum gallium nitride layer formed in the growth stage is too thin, and production efficiency is affected; if the thickness of the P-type doped aluminum gallium nitride layer formed in the growth stage is greater than 9nm, part of reactants may not be removed in time due to the fact that the P-type doped aluminum gallium nitride layer formed in the growth stage is too thick, the residual reactants may diffuse in the electron blocking layer, aluminum elements are not uniformly distributed in the electron blocking layer, hole injection into the active layer is affected, and the light emitting efficiency of the LED is finally reduced.

Preferably, the number of growth cycles may be 10 to 50, preferably 30.

If the number of the growth cycles is less than 10, part of reactants may not be removed in time due to the small number of the growth cycles, the residual reactants may diffuse in the electron blocking layer, the aluminum element is not uniformly distributed in the electron blocking layer, the hole injection into the active layer is affected, and the light emitting efficiency of the LED is finally reduced; if the number of growth cycles is greater than 50, the production efficiency may be reduced due to the greater number of growth cycles.

Further, the thickness of the electron blocking layer may be 20nm to 150nm, preferably 90 nm.

If the thickness of the electron blocking layer is less than 20nm, the electron blocking layer is too thin to effectively block electrons from jumping into the P-type semiconductor layer, so that the LED chip leaks electricity; if the thickness of the electron blocking layer is greater than 150nm, hole injection into the active layer may be affected due to the electron blocking layer being too thick, reducing the luminous efficiency of the LED.

Alternatively, the temperature in the reaction chamber during the treatment phase may be the same as the temperature in the reaction chamber during the growth phase, and the pressure in the reaction chamber during the treatment phase may be the same as the pressure in the reaction chamber during the growth phase.

The same temperature and pressure are adopted in the treatment stage and the growth stage, and the method is simple and convenient to realize.

Preferably, the temperature of the reaction chamber during the discontinuous growth of the electron blocking layer can be 850-1000 ℃, and is preferably 900 ℃; the pressure of the reaction chamber during the discontinuous growth of the electron blocking layer may be 100torr to 500torr, and preferably 300 torr.

And matching the temperature and the pressure in the reaction cavity to obtain the electron barrier layer with better crystal quality.

Optionally, before step 103, the manufacturing method may further include:

a low temperature P-type layer is grown on the active layer.

The low-temperature P-type layer prevents indium atoms in the active layer from being separated out due to the high growth temperature of the electron blocking layer, and the light emitting efficiency of the light emitting diode is influenced.

Accordingly, an electron blocking layer is grown on the low temperature P-type layer.

Specifically, the material of the low-temperature P-type layer may be the same as that of the P-type semiconductor layer. In this embodiment, the material of the low temperature P-type layer may be P-type doped gan.

Further, the thickness of the low-temperature P-type layer may be 10nm to 50nm, preferably 30 nm; the doping concentration of the P-type dopant in the low-temperature P-type layer may be 10¹⁸/cm³～10²⁰/cm³Preferably 10¹⁹/cm³。

Specifically, growing the low temperature P-type layer on the active layer may include:

the temperature is controlled to be 600 ℃ to 850 ℃ (preferably 750 ℃) and the pressure is controlled to be 100torr to 600torr (preferably 300torr), and the low-temperature P type layer is grown on the active layer.

Step 104: and growing a P-type semiconductor layer on the electron blocking layer.

Specifically, the P-type semiconductor layer may be made of P-type doped (e.g., magnesium) gallium nitride.

Further, the thickness of the P-type semiconductor layer may be 100nm to 500nm, preferably 300 nm; the doping concentration of the P-type dopant in the P-type semiconductor layer may be 10¹⁸/cm³～10²⁰/cm³Preferably 10¹⁹/cm³。

In an implementation manner of this embodiment, the step 104 may include:

the P-type semiconductor layer is grown on the active layer at a controlled temperature of 850 to 1000 deg.c (preferably 900 deg.c) and a pressure of 100to 300torr (preferably 200 torr).

In another implementation manner of this embodiment, the step 104 may include:

Specifically, the process of intermittently growing the P-type semiconductor layer is substantially the same as the process of intermittently growing the electron blocking layer, except that the reactants are different. Specifically, all reactants for intermittently growing the P-type semiconductor layer include a gallium source, ammonia gas, and a P-type dopant, and all reactants for intermittently growing the electron blocking layer include an aluminum source, a gallium source, ammonia gas, and a P-type dopant. I.e. discontinuous growth comprises a plurality of growth cycles occurring in sequence, each growth cycle comprising a growth phase and a treatment phase occurring after the growth phase. And in the growth stage, all reactants for growing the P-type semiconductor layer are continuously introduced into the reaction cavity to grow the P-type semiconductor layer. And in the treatment stage, stopping introducing part or all of reactants for growing the P-type semiconductor layer into the reaction cavity, and continuously introducing hydrogen into the reaction cavity to remove the reactants remaining on the surface of the P-type semiconductor layer.

The P-type semiconductor layer is grown discontinuously by adopting a plurality of growth periods which appear in sequence, each growth period comprises a growth stage and a treatment stage, and all reactants for growing the P-type semiconductor layer are continuously introduced into the reaction cavity during the growth stage, so that the P-type semiconductor layer can be grown; and stopping introducing part or all of reactants for growing the P-type semiconductor layer into the reaction cavity during a treatment stage after the growth stage, and continuously introducing hydrogen into the reaction cavity, so that the growth of the P-type semiconductor layer can be stopped, and simultaneously atoms can obtain a longer free path, so that reactants remained on the surface of the P-type semiconductor layer can be removed as soon as possible, only formed crystals are left on the surface of the P-type semiconductor layer, the unreacted reactants are prevented from being diffused into subsequently grown crystals, the interface between the P-type semiconductor layer and a semiconductor layer (such as a P-type contact layer) on the P-type semiconductor layer is clear, the defects generated on the interface are reduced, the overall crystal quality of the epitaxial wafer is improved, the mobility of holes is improved, the recombination efficiency of holes and electrons in the active layer is improved, and the luminous efficiency of the LED is finally improved.

Optionally, after step 104, the manufacturing method may further include:

the temperature is controlled to be 850 to 1050 ℃ (preferably 950 ℃), and the pressure is controlled to be 100to 300torr (preferably 200torr), and the P-type contact layer is grown on the P-type semiconductor layer.

Ohmic contact is formed between the P-type contact layer and an electrode or a transparent conductive film formed in the chip manufacturing process.

Specifically, the P-type contact layer may be made of P-type doped indium gallium nitride.

Further, the thickness of the P-type contact layer may be 5nm to 100nm, preferably 50 nm; the doping concentration of the P-type dopant in the P-type contact layer may be 10²¹/cm³～10²²/cm³Preferably 5 x 10²¹/cm³。

Specifically, growing the P-type contact layer on the P-type semiconductor layer may include:

After the completion of the epitaxial growth, the temperature is lowered to 650 to 850 ℃ (preferably 750 ℃), the epitaxial wafer is annealed in a nitrogen atmosphere for 5 to 15 minutes (preferably 10 minutes), and then the temperature of the epitaxial wafer is lowered to room temperature.

The control of the temperature and the pressure both refer to the control of the temperature and the pressure in a reaction chamber for growing the epitaxial wafer, and specifically refer to the reaction chamber of a Metal-organic Chemical Vapor Deposition (MOCVD) device. During implementation, trimethyl gallium or triethyl gallium is used as a gallium source, high-purity ammonia gas is used as a nitrogen source, trimethyl indium is used as an indium source, trimethyl aluminum is used as an aluminum source, silane is used as an N-type dopant, and magnesium diclocide is used as a P-type dopant.

One specific implementation of the manufacturing method shown in fig. 1 may include:

step 201: a substrate is provided and placed in the reaction chamber.

Step 202: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 203: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 204: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 10 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 50 s; and in the treatment stage, stopping introducing an aluminum source, ammonia gas and a P-type dopant into the reaction cavity, continuously introducing a gallium source with the flow of 550sccm into the reaction cavity, continuously introducing hydrogen with the flow of 50L/min into the reaction cavity, and removing the residual aluminum element on the surface of the P-type doped aluminum gallium nitride layer, wherein the duration of the treatment stage is 15 s.

Step 205: controlling the temperature at 900 deg.C and the pressure at 200torr, and growing a P-type semiconductor layer with a thickness of 300nm on the active layer, wherein the doping concentration of P-type dopant in the P-type semiconductor layer is 10¹⁹cm^-3。

And preparing the obtained epitaxial wafer into a chip, and compared with a chip prepared by continuously introducing an aluminum source, a gallium source, ammonia and a P-type dopant into the reaction cavity in the growth process of the electron blocking layer (the introduction flow rates of the aluminum source, the gallium source, the ammonia and the P-type dopant in the two chips are the same, the growth temperature and the growth pressure of the electron blocking layer are the same, and the growth conditions of the N-type semiconductor layer, the active layer and the P-type semiconductor layer are the same), the light efficiency of the chip is improved. 1 to 2 percent.

Another specific implementation of the manufacturing method shown in fig. 1 may include:

step 301: a substrate is provided and placed in the reaction chamber.

Step 302: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 303: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 304: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 30 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 30 s; and in the treatment stage, stopping introducing an aluminum source, ammonia gas and a P-type dopant into the reaction cavity, continuously introducing a gallium source with the flow rate of 550sccm into the reaction cavity, continuously introducing hydrogen with the flow rate of 50L/min into the reaction cavity, removing the residual aluminum element on the surface of the P-type doped aluminum gallium nitride layer, wherein the duration of the treatment stage is 10 s.

Step 305: controlling the temperature at 900 deg.C and the pressure at 200torr, and growing a P-type semiconductor layer with a thickness of 300nm on the active layer, wherein the doping concentration of P-type dopant in the P-type semiconductor layer is 10¹⁹cm^-3。

And preparing the obtained epitaxial wafer into a chip, wherein the light efficiency of the chip is improved by 3% -5% compared with a chip prepared by continuously introducing an aluminum source, a gallium source, ammonia and a P-type dopant into a reaction cavity in the growth process of the electron blocking layer (the introduction flow rates of the aluminum source, the gallium source, the ammonia and the P-type dopant in the two chips are the same, the growth temperature and the growth pressure of the electron blocking layer are the same, and the growth conditions of the N-type semiconductor layer, the active layer and the P-type semiconductor layer are the same).

Still another specific implementation manner of the manufacturing method shown in fig. 1 may include:

step 401: a substrate is provided and placed in the reaction chamber.

Step 402: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 403: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 404: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 50 growth cycles occurring in sequence, each growth cycle comprising a growth phase and a treatment phase occurring after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 10 s; and in the treatment stage, stopping introducing an aluminum source, ammonia gas and a P-type dopant into the reaction cavity, continuously introducing a gallium source with the flow of 550sccm into the reaction cavity, continuously introducing hydrogen with the flow of 50L/min into the reaction cavity, and removing the residual aluminum element on the surface of the P-type doped aluminum gallium nitride layer, wherein the duration of the treatment stage is 5 s.

Step 405: controlling the temperature at 900 deg.C and the pressure at 200torr, and growing a P-type semiconductor layer with a thickness of 300nm on the active layer, wherein the doping concentration of P-type dopant in the P-type semiconductor layer is 10¹⁹cm^-3。

And preparing the obtained epitaxial wafer into a chip, wherein the light efficiency of the chip is improved by 4-6% compared with a chip prepared by continuously introducing an aluminum source, a gallium source, ammonia and a P-type dopant into a reaction cavity in the growth process of the electron blocking layer (the introduction flow rates of the aluminum source, the gallium source, the ammonia and the P-type dopant in the two chips are the same, the growth temperature and the growth pressure of the electron blocking layer are the same, and the growth conditions of the N-type semiconductor layer, the active layer and the P-type semiconductor layer are the same).

step 501: a substrate is provided and placed in the reaction chamber.

Step 502: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 503: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 504: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 10 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 50 s; and in the treatment stage, stopping introducing an aluminum source, a gallium source and a P-type dopant into the reaction cavity, continuously introducing ammonia gas with the flow rate of 30L/min into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing the residual aluminum element on the surface of the P-type doped aluminum gallium nitride layer, wherein the duration of the treatment stage is 15 s.

Step 505: controlling the temperature at 900 deg.C and the pressure at 200torr, and growing a P-type semiconductor layer with a thickness of 300nm on the active layer, wherein the doping concentration of P-type dopant in the P-type semiconductor layer is 10¹⁹cm^-3。

And preparing the obtained epitaxial wafer into a chip, wherein the light efficiency of the chip is improved by 2-3% compared with a chip prepared by continuously introducing an aluminum source, a gallium source, ammonia and a P-type dopant into a reaction cavity in the growth process of the electron blocking layer (the introduction flow rates of the aluminum source, the gallium source, the ammonia and the P-type dopant in the two chips are the same, the growth temperature and the growth pressure of the electron blocking layer are the same, and the growth conditions of the N-type semiconductor layer, the active layer and the P-type semiconductor layer are the same).

step 601: a substrate is provided and placed in the reaction chamber.

Step 602: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 603: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 604: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 30 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 30 s; and in the treatment stage, stopping introducing an aluminum source, a gallium source and a P-type dopant into the reaction cavity, continuously introducing ammonia gas with the flow rate of 30L/min into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing the residual aluminum element on the surface of the P-type doped aluminum gallium nitride layer, wherein the duration of the treatment stage is 10 s.

Step 605: controlling the temperature at 900 ℃ and the pressure at 200torr, and growing the film on the active layer to be thickA P-type semiconductor layer with a doping concentration of 10¹⁹cm^-3。

step 701: a substrate is provided and placed in the reaction chamber.

Step 702: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 703: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 704: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 50 growth cycles occurring in sequence, each growth cycle comprising a growth phase and a treatment phase occurring after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 10 s; and in the treatment stage, stopping introducing an aluminum source, a gallium source and a P-type dopant into the reaction cavity, continuously introducing ammonia gas with the flow rate of 30L/min into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing the residual aluminum element on the surface of the P-type doped aluminum gallium nitride layer, wherein the duration of the treatment stage is 5 s.

Step 705: controlling the temperature at 900 deg.C and the pressure at 200torr, and growing a P-type semiconductor layer with a thickness of 300nm on the active layer, wherein the doping concentration of P-type dopant in the P-type semiconductor layer is 10¹⁹cm^-3。

step 801: a substrate is provided and placed in the reaction chamber.

Step 802: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 803: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 804: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 10 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 50 s; and in the treatment stage, stopping introducing an aluminum source, a gallium source, ammonia gas and a P-type dopant into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing residual aluminum elements on the surface of the P-type doped aluminum gallium nitride layer, and keeping the treatment stage for 15 s.

Step 805: controlling the temperature at 900 deg.C and the pressure at 200torr, and growing a P-type semiconductor layer with a thickness of 300nm on the active layer, wherein the doping concentration of P-type dopant in the P-type semiconductor layer is 10¹⁹cm^-3。

And preparing the obtained epitaxial wafer into a chip, wherein the light efficiency of the chip is improved by 1-2% compared with a chip prepared by continuously introducing an aluminum source, a gallium source, ammonia and a P-type dopant into a reaction cavity in the growth process of the electron blocking layer (the introduction flow rates of the aluminum source, the gallium source, the ammonia and the P-type dopant in the two chips are the same, the growth temperature and the growth pressure of the electron blocking layer are the same, and the growth conditions of the N-type semiconductor layer, the active layer and the P-type semiconductor layer are the same).

step 901: a substrate is provided and placed in the reaction chamber.

Step 902: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 903: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 904: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 30 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 30 s; and in the treatment stage, stopping introducing an aluminum source, a gallium source, ammonia gas and a P-type dopant into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing residual aluminum elements on the surface of the P-type doped aluminum gallium nitride layer, and keeping the treatment stage for 10 s.

Step 905: controlling the temperature at 900 deg.C and the pressure at 200torr, and growing a P-type semiconductor layer with a thickness of 300nm on the active layer, wherein the doping concentration of P-type dopant in the P-type semiconductor layer is 10¹⁹cm^-3。

step 1001: a substrate is provided and placed in the reaction chamber.

Step 1002: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 1003: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 1004: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 50 growth cycles occurring in sequence, each growth cycle comprising a growth phase and a treatment phase occurring after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 10 s; and in the treatment stage, stopping introducing an aluminum source, a gallium source, ammonia gas and a P-type dopant into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing residual aluminum elements on the surface of the P-type doped aluminum gallium nitride layer, and keeping the treatment stage for 5 s.

Step 1005: controlling the temperature at 900 deg.C and the pressure at 200torr, and growing a P-type semiconductor layer with a thickness of 300nm on the active layer, wherein the doping concentration of P-type dopant in the P-type semiconductor layer is 10¹⁹cm^-3。

And preparing the obtained epitaxial wafer into a chip, wherein the light efficiency of the chip is improved by 5-6% compared with a chip prepared by continuously introducing an aluminum source, a gallium source, ammonia and a P-type dopant into a reaction cavity in the growth process of the electron blocking layer (the introduction flow rates of the aluminum source, the gallium source, the ammonia and the P-type dopant in the two chips are the same, the growth temperature and the growth pressure of the electron blocking layer are the same, and the growth conditions of the N-type semiconductor layer, the active layer and the P-type semiconductor layer are the same).

step 1101: a substrate is provided and placed in the reaction chamber.

Step 1102: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 1103: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 1104: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 30 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 30 s; and in the treatment stage, stopping introducing an aluminum source, a gallium source and a P-type dopant into the reaction cavity, continuously introducing ammonia gas with the flow rate of 30L/min into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing the residual aluminum element on the surface of the P-type doped aluminum gallium nitride layer, wherein the duration of the treatment stage is 10 s.

Step 1105: controlling the temperature to be 900 ℃ and the pressure to be 200torr, and discontinuously growing a P-type semiconductor layer on the active layer; the discontinuous growth comprises 30 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm are continuously introduced into the reaction chamber to form a P-type doped gallium nitride layer, and the duration of the growth stage is 30 s; and in the treatment stage, stopping introducing the gallium source and the P-type dopant into the reaction cavity, continuously introducing ammonia gas with the flow rate of 30L/min into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing the P-type dopant remained on the surface of the P-type doped gallium nitride layer, wherein the duration of the treatment stage is 10 s.

And preparing the obtained epitaxial wafer into a chip, and compared with a chip prepared by continuously introducing an aluminum source, a gallium source, ammonia gas and a P-type dopant into a reaction cavity in the growth process of an electron barrier layer and continuously introducing the gallium source, the ammonia gas and the P-type dopant into the reaction cavity in the growth process of a P-type semiconductor layer (the introduction flow rates of the aluminum source, the gallium source, the ammonia gas and the P-type dopant are the same when the electron barrier layer grows in the two chips, the growth temperature and the growth pressure of the electron barrier layer are the same, the introduction flow rates of the gallium source, the ammonia gas and the P-type dopant are the same when the P-type semiconductor layer grows, the growth temperature and the growth pressure of the P-type semiconductor layer are the same, and the growth conditions of.

step 1201: a substrate is provided and placed in the reaction chamber.

Step 1202: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 1203: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 1204: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 30 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 30 s; and in the treatment stage, stopping introducing an aluminum source, a gallium source and a P-type dopant into the reaction cavity, continuously introducing ammonia gas with the flow rate of 30L/min into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing the residual aluminum element on the surface of the P-type doped aluminum gallium nitride layer, wherein the duration of the treatment stage is 10 s.

Step 1205: controlling the temperature to be 900 ℃ and the pressure to be 200torr, and discontinuously growing a P-type semiconductor layer on the active layer; the discontinuous growth comprises 10 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm are continuously introduced into the reaction chamber to form a P-type doped gallium nitride layer, and the duration of the growth stage is 50 s; and in the treatment stage, stopping introducing the gallium source and the P-type dopant into the reaction cavity, continuously introducing ammonia gas with the flow rate of 30L/min into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, and removing the P-type dopant remained on the surface of the P-type doped gallium nitride layer, wherein the duration of the treatment stage is 15 s.

step 1301: a substrate is provided and placed in the reaction chamber.

Step 1302: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 1303: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 1304: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 30 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 30 s; and in the treatment stage, stopping introducing an aluminum source, a gallium source and a P-type dopant into the reaction cavity, continuously introducing ammonia gas with the flow rate of 30L/min into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing the residual aluminum element on the surface of the P-type doped aluminum gallium nitride layer, wherein the duration of the treatment stage is 10 s.

Step 1305: controlling the temperature to be 900 ℃ and the pressure to be 200torr, and discontinuously growing a P-type semiconductor layer on the active layer; the discontinuous growth comprises 50 growth cycles occurring in sequence, each growth cycle comprising a growth phase and a treatment phase occurring after the growth phase; in the growth stage, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm are continuously introduced into the reaction chamber to form a P-type doped gallium nitride layer, and the duration of the growth stage is 10 s; and in the treatment stage, stopping introducing the gallium source and the P-type dopant into the reaction cavity, continuously introducing ammonia gas with the flow rate of 30L/min into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing the P-type dopant remained on the surface of the P-type doped gallium nitride layer, and keeping the treatment stage for 5 s.

step 1401: a substrate is provided and placed in the reaction chamber.

Step 1402: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 1403: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 1404: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 30 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 30 s; and in the treatment stage, stopping introducing an aluminum source, a gallium source and a P-type dopant into the reaction cavity, continuously introducing ammonia gas with the flow rate of 30L/min into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing the residual aluminum element on the surface of the P-type doped aluminum gallium nitride layer, wherein the duration of the treatment stage is 10 s.

Step 1405: controlling the temperature to be 900 ℃ and the pressure to be 200torr, and discontinuously growing a P-type semiconductor layer on the active layer; the discontinuous growth comprises 30 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm are continuously introduced into the reaction chamber to form a P-type doped gallium nitride layer, and the duration of the growth stage is 30 s; and in the treatment stage, stopping introducing ammonia gas and a P-type dopant into the reaction cavity, continuously introducing a gallium source with the flow of 550sccm into the reaction cavity, continuously introducing hydrogen with the flow of 50L/min into the reaction cavity, and removing the P-type dopant remaining on the surface of the P-type doped gallium nitride layer, wherein the duration of the treatment stage is 10 s.

step 1501: a substrate is provided and placed in the reaction chamber.

Step 1502: an N-type semiconductor layer was grown on the substrate at 1050 ℃ and 300 torr.

Step 1503: growing an active layer on the N-type semiconductor layer, wherein the active layer comprises 8 quantum wells and 8 quantum barriers which are alternately grown; the thickness of the quantum well is 3.5nm, the growth temperature of the quantum well is 760 ℃, and the growth pressure of the quantum well is 300 torr; the thickness of the quantum barrier is 15nm, the growth temperature of the quantum barrier is 900 ℃, and the growth pressure of the quantum barrier is 300 torr.

Step 1504: controlling the temperature to be 900 ℃ and the pressure to be 300torr, and discontinuously growing an electron blocking layer on the active layer; the discontinuous growth comprises 30 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, continuously introducing an aluminum source with the flow rate of 260sccm, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm into the reaction cavity to form a P-type doped aluminum gallium nitride layer, wherein the duration of the growth stage is 30 s; and in the treatment stage, stopping introducing an aluminum source, a gallium source and a P-type dopant into the reaction cavity, continuously introducing ammonia gas with the flow rate of 30L/min into the reaction cavity, continuously introducing hydrogen gas with the flow rate of 50L/min into the reaction cavity, removing the residual aluminum element on the surface of the P-type doped aluminum gallium nitride layer, wherein the duration of the treatment stage is 10 s.

Step 1505: controlling the temperature to be 900 ℃ and the pressure to be 200torr, and discontinuously growing a P-type semiconductor layer on the active layer; the discontinuous growth comprises 30 growth cycles which occur in sequence, each growth cycle comprising a growth phase and a treatment phase which occurs after the growth phase; in the growth stage, a gallium source with the flow rate of 550sccm, ammonia gas with the flow rate of 30L/min and a P-type dopant with the flow rate of 400sccm are continuously introduced into the reaction chamber to form a P-type doped gallium nitride layer, and the duration of the growth stage is 30 s; and in the treatment stage, stopping introducing the gallium source, the ammonia gas and the P-type dopant into the reaction cavity, continuously introducing hydrogen with the flow rate of 50L/min into the reaction cavity, and removing the P-type dopant remained on the surface of the P-type doped gallium nitride layer, wherein the duration of the treatment stage is 10 s.

The embodiment of the invention provides a gallium nitride-based light emitting diode epitaxial wafer which is suitable for being manufactured by adopting the manufacturing method shown in FIG. 1. Fig. 5 is a schematic structural diagram of an epitaxial wafer of a gallium nitride-based light emitting diode according to an embodiment of the present invention. Referring to fig. 5, the gan-based light emitting diode epitaxial wafer includes a substrate 10, an N-type semiconductor layer 20, an active layer 30, an electron blocking layer 40, and a P-type semiconductor layer 50, and the N-type semiconductor layer 20, the active layer 30, the electron blocking layer 40, and the P-type semiconductor layer 50 are sequentially stacked on the substrate 10.

In the present embodiment, the electron blocking layer 40 includes a plurality of sub-layers stacked in sequence, and the surface of each sub-layer is a surface treated with hydrogen gas.

Alternatively, the P-type semiconductor layer 50 may include a plurality of sub-layers stacked in sequence, and a surface of each sub-layer is a surface treated with hydrogen gas.

Alternatively, as shown in fig. 5, the gan-based led epitaxial wafer may further include a buffer layer 61, and the buffer layer 61 is disposed between the substrate 10 and the N-type semiconductor layer 20.

Preferably, as shown in fig. 5, the gan-based led epitaxial wafer may further include an undoped gan layer 62, the undoped gan layer 62 being disposed between the buffer layer 61 and the N-type semiconductor layer 20.

Optionally, as shown in fig. 5, the gan-based led epitaxial wafer may further include a stress relief layer 70, and the stress relief layer 70 is disposed between the N-type semiconductor layer 20 and the active layer 30.

Optionally, as shown in fig. 5, the gan-based led epitaxial wafer may further include a low temperature P-type layer 80, and the low temperature P-type layer 80 is disposed between the active layer 30 and the electron blocking layer 40.

Optionally, as shown in fig. 5, the gan-based led epitaxial wafer may further include a P-type contact layer 90, and the P-type contact layer 90 is disposed on the P-type semiconductor layer 50.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A manufacturing method of a gallium nitride-based light emitting diode epitaxial wafer is characterized by comprising the following steps:

providing a substrate and placing the substrate in a reaction chamber;

and growing a P-type semiconductor layer on the electron blocking layer.

2. The method according to claim 1, wherein the step of continuously introducing all reactants for growing the electron blocking layer into the reaction chamber during the growth stage to grow the electron blocking layer comprises:

3. The method according to claim 2, wherein the step of stopping introducing part or all of the reactants for growing the electron blocking layer into the reaction chamber during the treatment stage, and continuously introducing hydrogen into the reaction chamber to remove the residual reactants on the surface of the electron blocking layer comprises:

4. The method according to claim 2, wherein the step of stopping introducing part or all of the reactants for growing the electron blocking layer into the reaction chamber during the treatment stage, and continuously introducing hydrogen into the reaction chamber to remove the residual reactants on the surface of the electron blocking layer comprises:

5. The method according to claim 2, wherein the step of stopping introducing part or all of the reactants for growing the electron blocking layer into the reaction chamber during the treatment stage, and continuously introducing hydrogen into the reaction chamber to remove the residual reactants on the surface of the electron blocking layer comprises:

6. The method according to any one of claims 2 to 5, wherein the aluminum source is introduced at a flow rate of 20sccm to 500sccm, the gallium source is introduced at a flow rate of 200sccm to 900sccm, the ammonia gas is introduced at a flow rate of 5L/min to 50L/min, and the P-type dopant is introduced at a flow rate of 50sccm to 800 sccm.

7. The method according to claim 6, wherein the flow rate of the hydrogen gas is 5 to 100L/min.

8. The method of claim 7, wherein the duration of the treatment phase is between 5s and 15 s.

9. The method according to any one of claims 1 to 5, wherein the growing the P-type semiconductor layer on the electron blocking layer comprises:

discontinuously growing a P-type semiconductor layer on the electron blocking layer; the discontinuously grown P-type semiconductor layer comprises a plurality of growth cycles which appear in sequence, and each growth cycle of the discontinuously grown P-type semiconductor layer comprises a growth phase and a treatment phase which appears after the growth phase; continuously introducing all reactants for growing the P-type semiconductor layer into the reaction cavity during the growth stage of the discontinuously grown P-type semiconductor layer to grow the P-type semiconductor layer; and stopping introducing part or all of reactants for growing the P-type semiconductor layer into the reaction cavity during the treatment stage of the intermittent growth of the P-type semiconductor layer, and continuously introducing hydrogen into the reaction cavity to remove the residual reactants on the surface of the P-type semiconductor layer.

10. The utility model provides a gallium nitride base emitting diode epitaxial wafer, gallium nitride base emitting diode epitaxial wafer includes substrate, N type semiconductor layer, active layer, electron barrier layer and P type semiconductor layer, N type semiconductor layer the active layer the electron barrier layer with P type semiconductor layer stacks gradually on the substrate, its characterized in that, the electron barrier layer includes a plurality of sublayers that stack gradually, every the surface of sublayer is the surface that adopts hydrogen to handle.