Method for manufacturing active region of indium arsenide / indium phosphide quantum dot laser

Abstract

The invention discloses a method for manufacturing an active region of an indium arsenide / indium phosphide quantum dot laser. The method comprises the following steps: selecting an indium phosphide substrate; epitaxially growing a layer of indium aluminum arsenic on the substrate; growing a layer of indium aluminum gallium arsenic; epitaxially growing a multi-cycle indium arsenide quantum dot active layer, including growing indium arsenide quantum dots, growing an indium-aluminum-gallium-arsenic layer matched with indium phosphide lattices on the indium arsenide quantum dots, growing a stress adjusting layer on the indium-aluminum-gallium-arsenic layer, and growing a separation layer matched with the indium phosphide lattices on the stress adjusting layer; or growing the indium arsenide quantum dots, growing one or two growth stress adjusting layers on the indium arsenide quantum dots, and growing the separation layers on the stress adjusting layers; epitaxially growing indium aluminum gallium arsenic on the quantum dot active layer; epitaxial growth of indium aluminum arsenic is carried out; epitaxially growing a layer of indium phosphide as a light limiting layer; and finally epitaxially growing indium gallium arsenic as a contact layer to complete the preparation of the active region of the quantum dot laser. The optical properties of the quantum dots are ensured while the wavelength is adjusted.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor preparation, and in particular relates to a method for manufacturing an indium arsenide / indium phosphide quantum dot laser active region. Background Art

[0002] Fiber-optic communication is gradually replacing copper interconnects due to its greater channel density, higher data transmission speed, longer transmission distance and lower cost to meet today's rapidly expanding data transmission needs. The 1.55-micron band is the lowest transmission loss window for fiber-optic communication, so semiconductor lasers in this band have received widespread attention due to their potential applications in medium- and long-distance (10-80 kilometers and above) fiber-optic communication systems. Indium phosphide-based material systems are currently the most widely used 1.55-micron optical communication light sources. Secondly, indium phosphide-based sensors have better safety. The light waves emitted by the device with a wavelength of around 1.55 microns avoid the band that can cause damage to the human eye (less than 1400 nanometers), which can better protect eye safety than gallium arsenide-based sensors, so it has natural advantages in wearable devices, face and gesture recognition, industrial sensors and controllers, etc. 1.55-micron lidar can safely emit higher energy and transmit longer distances, and has key advantages in autonomous driving and robotics.

[0003] Self-organized quantum dot systems have become a hot topic of research due to their superior optoelectronic properties and insensitivity to defects. According to theoretical research and experimental verification, zero-dimensional quantum dot lasers have higher temperature stability, greater gain, and lower threshold current than traditional quantum well lasers. In addition, the insensitivity of quantum dots to material defects makes them a decisive factor in the growth and preparation of silicon-on-silicon lasers to achieve silicon-based optoelectronic integration. Compared with the mature growth technology of gallium arsenide-based indium arsenide quantum dots, the difficulty of growing indium phosphide-based indium arsenide quantum dots lies in their smaller lattice mismatch, the uneven stress field on the surface of the barrier of indium aluminum gallium arsenide or indium gallium arsenide phosphide quaternary compounds commonly used in the indium phosphide material system, and the diffusion of indium atoms, which makes it difficult to form a uniform quantum dot morphology. The growth of indium phosphide-based quantum dots is very easy to form quantum short wires rather than quantum dots, and this kind of quantum short wire will cause the photoluminescence spectrum of the active region to have a large half-maximum full width due to the anisotropy of the morphology itself, which is basically around 70 meV at room temperature and rarely below 60 meV. In addition, controlling the room temperature emission wavelength at 1.55 microns is also a major focus of the growth of indium phosphide quantum dots. The current international methods for preparing high-density, high-uniformity 1.55-micron indium phosphide-based quantum dots include growing on indium phosphide substrates, adjusting the growth interval, adjusting the arsenic-phosphorus exchange method, adjusting the growth parameters including the V / III ratio, growth rate, growth temperature, As4 / As2 selection, and adjusting the capping method to optimize the growth. High density, quantum dot morphology, and quantum dot growth with an emission wavelength of 1.55 microns have all been prepared separately, but the research results that meet the above conditions at the same time are still very limited.

[0004] In order to improve the luminous efficiency and adjust the luminous wavelength, the two-step growth method is derived from indium arsenide / gallium arsenide quantum dots and is applied to the growth of 1.55 micron indium phosphide-based quantum dots. The specific operation method is generally to grow a thin layer of indium gallium arsenic phosphide or indium gallium arsenic at the same temperature after the quantum dot layer is grown, so that some quantum dots are completely covered and large dots are exposed, and then the indium is evaporated by increasing the substrate temperature to increase the uniformity of the dots. Subsequently, the second cap layer (usually indium gallium arsenic phosphide or indium gallium arsenic) will continue to grow to the thickness of the separation layer at high temperature to achieve the growth of multi-layer quantum dots. Alternatively, the first cap layer can also be used as an indium phosphide cap layer to adjust the dot size through arsenic / phosphorus exchange to adjust the luminous wavelength. However, for this method, the luminous wavelength depends largely on the thickness of the first cap layer, and if the thickness of the first cap layer is very thin, a lot of the volume of the luminescent quantum dots will be lost, and the luminous efficiency will decrease. The method of adjusting the luminous wavelength by arsenic / phosphorus exchange is prone to cause the boundary of the quantum dots to be blurred, reducing the carrier confinement ability of the quantum dots. In this research context, the present invention proposes a method for growing the active region of an InAs / InP quantum dot laser that combines a stress layer (which is also a bandgap width adjustment layer) with a two-step capping layer growth method, which can better ensure the optical performance while achieving the adjustment of the emission wavelength in a wider range. Summary of the invention

[0005] In view of the above technical problems, the present invention provides a method for manufacturing an active region of an InAs / InP quantum dot laser.

[0006] The technical solution adopted by the present invention to solve the technical problem is: A method for making an indium arsenide / indium phosphide quantum dot laser active region, the method comprising the following steps: S100: selecting an indium phosphide substrate; S200: epitaxially growing a layer of indium aluminum arsenide lattice matching with indium phosphide on the indium phosphide substrate; S300: growing a layer of indium aluminum gallium arsenide lattice-matched with indium phosphide on the indium aluminum arsenide layer; S400: epitaxially growing a multi-period indium arsenide quantum dot active layer on the indium aluminum gallium arsenide layer; the indium arsenide quantum dot active layer includes growing indium arsenide quantum dots, growing an indium aluminum gallium arsenide layer lattice-matched with indium phosphide on the indium arsenide quantum dots, growing a stress adjustment layer on the indium aluminum gallium arsenide layer, and growing a separation layer lattice-matched with indium phosphide on the stress adjustment layer; or: growing indium arsenide quantum dots, growing one or two stress adjustment layers on the indium arsenide quantum dots, and growing a separation layer lattice-matched with indium phosphide on the stress adjustment layer; S500: epitaxial growth of InAlGaAs on the quantum dot active layer; S600: epitaxially growing indium aluminum arsenide on the indium aluminum gallium arsenide layer; S700: epitaxially growing a layer of indium phosphide on the indium aluminum arsenide layer as a light confinement layer; S800: Epitaxially grow InGaAs on InP as a contact layer to complete the preparation of the active region of the quantum dot laser.

[0007] Preferably, S100 specifically includes: An indium phosphide substrate is selected, which is an n+ type indium phosphide single crystal with a doping concentration of 1×10 18 cm -3 -2×10 19 cm -3 , the crystal orientation is 100, and the high temperature deoxidation layer is removed at 480℃-530℃ for 1 to 3 minutes. The high temperature deoxidation process can be protected by a phosphorus-rich or arsenic-rich environment.

[0008] Preferably, S200 is specifically: The lattice-matched n+ InAlAs layer of 100 nm–600 nm was grown on the InP substrate by molecular beam epitaxy (MBE) at 470°C–530°C with a doping concentration of 5×10 17 cm -3 -2×10 19 cm -3 , among which the ratio of five ethnic groups to three ethnic groups is greater than 25.

[0009] Preferably, S300 specifically includes: A lattice-matched n-type InAlGaAs layer is deposited on the InAlAs layer with a doping concentration of 1×10 16 cm -3 -5×10 18 cm -3 The growth temperature of the InAlGaAs layer is between 470°C and 530°C, the thickness is between 100nm and 400nm, and the ratio of Group V to Group III is greater than 25.

[0010] Preferably, the growth structure of the indium arsenide quantum dot active layer in S400 is specifically: InAs quantum dots were grown between 450°C and 520°C, with a growth rate of 0.1 ML / s to 0.7 ML / s, and a ratio of group V to group III of 1 to 30; Then grow a layer of indium aluminum gallium arsenide that matches the indium phosphide lattice with a thickness of 1nm-10nm, and the growth temperature is the same as the growth temperature of the quantum dots to partially cover the quantum dots; Then, a stress adjustment layer is grown. The stress adjustment layer is made of gallium arsenide, indium gallium arsenide, indium aluminum arsenide, or indium aluminum gallium arsenide or indium gallium arsenide phosphide whose lattice constant does not match that of indium phosphide. The growth temperature of the stress adjustment layer is the same as that of the quantum dots. The thickness is 0.5-20 monoatomic layers. The height of the quantum dots is controlled and the wavelength of the quantum dots is adjusted by the band gap width of the stress adjustment layer and the stress applied to the quantum dots. Then, the substrate temperature is increased to 500°C-570°C to evaporate indium. The quantum dots whose exposed height is higher than the thickness of the indium aluminum gallium arsenide layer and the stress adjustment layer are disintegrated, thereby improving the uniformity of the quantum dots. The remaining spacer layer lattice-matched to indium phosphide is then grown on the stress-modulating layer to eliminate stress accumulation and facilitate multi-layer quantum dot growth.

[0011] Preferably, the growth structure of the indium arsenide quantum dot active layer in S400 is specifically: InAs quantum dots were grown between 450°C and 520°C, with a growth rate of 0.1 ML / s to 0.7 ML / s, and a ratio of group V to group III of 1 to 30; Then, one or two stress adjustment layers are grown. The stress adjustment layers are made of gallium arsenide, indium gallium arsenide, indium aluminum arsenide, or indium aluminum gallium arsenide and indium gallium arsenide phosphide whose lattice constant does not match that of indium phosphide. The growth temperature of the stress adjustment layer is the same as that of the quantum dots or is directly increased to 500°C-540°C for growth, so as to achieve dual regulation of wavelength and luminous intensity. Then, the substrate temperature is increased to 500°C-570°C to evaporate indium. A spacer layer lattice-matched to InP is then grown on the stress-modulating layer.

[0012] Preferably, S500 is specifically: A lattice-matched p-type InAlGaAs layer was grown on the multilayer quantum dots with a doping concentration of 1×10 16 cm -3 -5×10 18 cm -3 The growth temperature of the InAlGaAs layer is between 470°C and 530°C, the thickness is between 100nm and 400nm, and the ratio of Group V to Group III is greater than 25.

[0013] Preferably, S600 specifically includes: On the p-type InAlGaAs layer, a lattice-matched p+ InAlAs layer is grown at 470°C-530°C with a doping concentration of 5×10 17 cm -3 -2×10 19 cm -3 , thickness is 100nm – 600nm, and the ratio of group V to group III is greater than 25.

[0014] Preferably, S700 specifically includes: A p+ InP light confinement layer of 1000nm–2000nm is grown on the p+ InAlAs layer with a doping concentration of 1×10 18 cm -3 -2×10 19 cm -3 The growth temperature is between 470℃-530℃, and the ratio of group V to group III is greater than 25.

[0015] Preferably, S800 specifically includes: A p+ InGaAs contact layer is grown on the p+ InP layer at 470°C-530°C with a thickness of 100nm-400nm and a doping concentration of 1×10 18 cm -3 -2×10 19 cm -3 , among which the ratio of five ethnic groups to three ethnic groups is greater than 25.

[0016] The above-mentioned method for making the active region of InAs / InP quantum dot laser uses a stress adjustment layer (bandgap adjustment layer) as the second capping layer (or the first capping layer or the two-step capping layer) in the two-step capping layer growth method to optimize the growth method of the active region of InAs / InP quantum dot laser, which can solve the problem of loss of light-emitting quantum dot volume caused by reducing the capping layer thickness in the ordinary two-step capping layer growth method, and ensure the optical properties of the quantum dots while adjusting the wavelength. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a flow chart of a method for manufacturing an active region of an InAs / InP quantum dot laser in one embodiment of the present invention; Figure 2 Schematic diagram of the growth structure of the active region of an InAs / InP quantum dot laser in one embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the quantum dot growth part in one embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the quantum dot growth part in another embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of the quantum dot growth part in another embodiment of the present invention. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings.

[0019] In one embodiment, Figure 1 and Figure 2 As shown, a method for making an InAs / InP quantum dot laser active region comprises the following steps: S100: selecting an indium phosphide substrate; S200: epitaxially growing a layer of indium aluminum arsenide lattice matching with indium phosphide on the indium phosphide substrate; S300: growing a layer of indium aluminum gallium arsenide lattice-matched with indium phosphide on the indium aluminum arsenide layer; S400: epitaxially growing a multi-period indium arsenide quantum dot active layer on the indium aluminum gallium arsenide layer; the indium arsenide quantum dot active layer includes growing indium arsenide quantum dots, growing an indium aluminum gallium arsenide layer lattice-matched with indium phosphide on the indium arsenide quantum dots, growing a stress adjustment layer on the indium aluminum gallium arsenide layer, and growing a separation layer lattice-matched with indium phosphide on the stress adjustment layer; or: growing indium arsenide quantum dots, growing one or two stress adjustment layers on the indium arsenide quantum dots, and growing a separation layer lattice-matched with indium phosphide on the stress adjustment layer; S500: epitaxial growth of InAlGaAs on the quantum dot active layer; S600: epitaxially growing indium aluminum arsenide on the indium aluminum gallium arsenide layer; S700: epitaxially growing a layer of indium phosphide on the indium aluminum arsenide layer as a light confinement layer; S800: Epitaxially grow InGaAs on InP as a contact layer to complete the preparation of the active region of the quantum dot laser.

[0020] The above-mentioned method for making the active region of InAs / InP quantum dot laser uses a stress adjustment layer (bandgap adjustment layer) as the second capping layer (or the first capping layer or the two-step capping layer) in the two-step capping layer growth method to optimize the growth method of the active region of InAs / InP quantum dot laser, which can solve the problem of loss of light-emitting quantum dot volume caused by reducing the capping layer thickness in the ordinary two-step capping layer growth method, and ensure the optical properties of the quantum dots while adjusting the wavelength.

[0021] In one embodiment, S100 specifically includes: An indium phosphide substrate is selected, which is an n+ type indium phosphide single crystal with a doping concentration of 1×10 18 cm -3 -2×10 19 cm -3 , the crystal orientation is 100, and the high temperature deoxidation layer is removed at 480℃-530℃ for 1 to 3 minutes. The high temperature deoxidation process can be protected by a phosphorus-rich or arsenic-rich environment.

[0022] In one embodiment, S200 specifically includes: The lattice-matched n+ InAlAs layer of 100 nm–600 nm was grown on the InP substrate by molecular beam epitaxy (MBE) at 470°C–530°C with a doping concentration of 5×10 17 cm -3 -2×10 19 cm -3, among which the ratio of five ethnic groups to three ethnic groups is greater than 25.

[0023] In one embodiment, S300 specifically includes: A lattice-matched n-type InAlGaAs layer is deposited on the InAlAs layer with a doping concentration of 1×10 16 cm -3 -5×10 18 cm -3 The growth temperature of the InAlGaAs layer is between 470°C and 530°C, the thickness is between 100nm and 400nm, and the ratio of Group V to Group III is greater than 25.

[0024] In one embodiment, Figure 3 As shown, the growth structure of the indium arsenide quantum dot active layer in S400 is specifically as follows: InAs quantum dots were grown between 450°C and 520°C, with a growth rate of 0.1 ML / s to 0.7 ML / s, and a ratio of group V to group III of 1 to 30; Then grow a layer of indium aluminum gallium arsenide that matches the indium phosphide lattice with a thickness of 1nm-10nm, and the growth temperature is the same as the growth temperature of the quantum dots to partially cover the quantum dots; Then, a stress adjustment layer (bandgap width adjustment layer) is grown. The stress adjustment layer is made of gallium arsenide, indium gallium arsenide, indium aluminum arsenide, or indium aluminum gallium arsenide, indium gallium arsenide phosphide, etc., whose lattice constant does not match that of indium phosphide. The growth temperature of the stress adjustment layer is the same as that of the quantum dots, and the thickness is 0.5-20 monoatomic layers, so as to control the height of the quantum dots and adjust the emission wavelength of the quantum dots by the bandgap width of the stress adjustment layer and the stress applied to the quantum dots. Then, the substrate temperature is increased to 500°C-570°C to evaporate indium, and the quantum dots whose height is higher than the thickness of the indium aluminum gallium arsenide layer and the stress adjustment layer are disintegrated, thereby improving the uniformity of the quantum dots. The remaining spacer layer lattice-matched to indium phosphide is then grown on the stress-modulating layer to eliminate stress accumulation and facilitate multi-layer quantum dot growth.

[0025] Specifically, the above structure can be repeated multiple times to achieve the growth of a multi-layer quantum dot laser active region.

[0026] In one embodiment, Figure 4 and Figure 5 As shown, the growth structure of the indium arsenide quantum dot active layer in S400 is specifically as follows: InAs quantum dots were grown between 450°C and 520°C, with a growth rate of 0.1 ML / s to 0.7 ML / s, and a ratio of group V to group III of 1 to 30; Then, one or two stress adjustment layers are grown. The stress adjustment layers are made of gallium arsenide, indium gallium arsenide, indium aluminum arsenide, or indium aluminum gallium arsenide, indium gallium arsenide phosphide, etc., whose lattice constant does not match that of indium phosphide. The growth temperature of the stress adjustment layer is the same as that of the quantum dots or is directly increased to 500°C-540°C for growth, so as to achieve dual regulation of wavelength and luminous intensity. Then, the substrate temperature is increased to 500°C-570°C to evaporate indium. A spacer layer lattice-matched to InP is then grown on the stress-modulating layer.

[0027] Specifically, a stress adjustment layer (bandgap adjustment layer) can also be directly grown on the indium arsenide quantum dots, such as gallium arsenide or high indium component indium gallium arsenic or indium gallium arsenic phosphide, or two stress adjustment layers can be directly grown on the indium arsenide quantum dots, such as using indium gallium arsenic as the original indium aluminum gallium arsenic layer and gallium arsenide as the original stress adjustment layer, gradually applying stress and changing the bandgap width of the quantum dot active region to adjust the emission wavelength.

[0028] In one embodiment, S500 specifically includes: A lattice-matched p-type InAlGaAs layer was grown on the multilayer quantum dots with a doping concentration of 1×10 16 cm -3 -5×10 18 cm -3 The growth temperature of the InAlGaAs layer is between 470°C and 530°C, the thickness is between 100nm and 400nm, and the ratio of Group V to Group III is greater than 25.

[0029] In one embodiment, S600 specifically includes: On the p-type InAlGaAs layer, a lattice-matched p+ InAlAs layer is grown at 470°C-530°C with a doping concentration of 5×10 17 cm -3 -2×10 19 cm -3 , thickness is 100nm – 600nm, and the ratio of group V to group III is greater than 25.

[0030] In one embodiment, S700 specifically includes: A p+ InP light confinement layer of 1000nm–2000nm is grown on the p+ InAlAs layer with a doping concentration of 1×10 18 cm -3 -2×10 19 cm -3 The growth temperature is between 470℃-530℃, and the ratio of group V to group III is greater than 25.

[0031] In one embodiment, S800 specifically includes: A p+ InGaAs contact layer is grown on the p+ InP layer at 470°C-530°C with a thickness of 100nm-400nm and a doping concentration of 1×10 18 cm -3 -2×10 19 cm -3 , among which the ratio of five ethnic groups to three ethnic groups is greater than 25.

[0032] The above method for making the active region of an indium arsenide / indium phosphide quantum dot laser uses gallium arsenide with a large lattice mismatch with the indium phosphide-based material system as the second cap layer (or the first cap layer or the two-step cap layer) of the two-step growth of indium arsenide / indium phosphide quantum dots to apply compressive stress to the quantum dots and introduces gallium arsenide with a wider bandgap, and combines the indium evaporation technology to change the size of the dots, so as to adjust the wavelength of the quantum dot emission while ensuring good optical performance. This method can be extended to the use of materials with larger lattices than the indium phosphide material system, such as indium gallium arsenic with a high indium component, to apply tensile stress to the quantum dots and introduce narrower bandgap materials as the second cap layer (or the first cap layer or the two-step cap layer) in the two-step growth cap layer technology to lengthen the wavelength of the quantum dots. This method can achieve controllable adjustment of the emission wavelength of indium arsenide / indium phosphide quantum dots within a large range (1.3-2 microns or even longer).

[0033] The above is a detailed introduction to the method for making the active region of the indium arsenide / indium phosphide quantum dot laser provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the core idea of ​​the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A method for making an indium arsenide / indium phosphide quantum dot laser active region, characterized in that: The method comprises the following steps: S100: selecting an indium phosphide substrate; S200: epitaxially growing a layer of indium aluminum arsenide lattice matching with indium phosphide on the indium phosphide substrate; S300: growing a layer of indium aluminum gallium arsenide lattice-matched with indium phosphide on the indium aluminum arsenide layer; S400: epitaxially growing a multi-period indium arsenide quantum dot active layer on the indium aluminum gallium arsenide layer; the indium arsenide quantum dot active layer includes growing indium arsenide quantum dots, growing an indium aluminum gallium arsenide layer lattice-matched with indium phosphide on the indium arsenide quantum dots, growing a stress adjustment layer on the indium aluminum gallium arsenide layer, and growing a separation layer lattice-matched with indium phosphide on the stress adjustment layer; or: growing indium arsenide quantum dots, growing one or two stress adjustment layers on the indium arsenide quantum dots, and growing a separation layer lattice-matched with indium phosphide on the stress adjustment layer; S500: epitaxial growth of InAlGaAs on the quantum dot active layer; S600: epitaxially growing indium aluminum arsenide on the indium aluminum gallium arsenide layer; S700: epitaxially growing a layer of indium phosphide on the indium aluminum arsenide layer as a light confinement layer; S800: Epitaxially grow InGaAs on InP as a contact layer to complete the preparation of the active region of the quantum dot laser.

2. The method according to claim 1, characterized in that S100 is specifically: An indium phosphide substrate is selected, which is an n+ type indium phosphide single crystal with a doping concentration of 1×10 18 cm -3 -2×10 19 cm -3 , the crystal orientation is 100, and the high temperature deoxidation layer is removed at 480℃-530℃ for 1 to 3 minutes. The high temperature deoxidation process can be protected by a phosphorus-rich or arsenic-rich environment.

3. The method according to claim 2, characterized in that S200 is specifically: The lattice-matched n+ InAlAs layer of 100 nm–600 nm was grown on the InP substrate by molecular beam epitaxy (MBE) at 470°C–530°C with a doping concentration of 5×10 17 cm -3 -2×10 19 cm -3 , among which the ratio of five ethnic groups to three ethnic groups is greater than 25.

4. The method according to claim 3, characterized in that S300 is specifically: A lattice-matched n-type InAlGaAs layer is deposited on the InAlAs layer with a doping concentration of 1×10 16 cm -3 -5×10 18 cm -3 The growth temperature of the InAlGaAs layer is between 470°C and 530°C, the thickness is between 100nm and 400nm, and the ratio of Group V to Group III is greater than 25.

5. The method according to claim 4, characterized in that The growth structure of the indium arsenide quantum dot active layer in S400 is as follows: InAs quantum dots were grown between 450°C and 520°C, with a growth rate of 0.1 ML / s to 0.7 ML / s, and a ratio of group V to group III of 1 to 30; Then grow a layer of indium aluminum gallium arsenide that matches the indium phosphide lattice with a thickness of 1nm-10nm, and the growth temperature is the same as the growth temperature of the quantum dots to partially cover the quantum dots; Then, a stress adjustment layer is grown. The stress adjustment layer is made of gallium arsenide, indium gallium arsenide, indium aluminum arsenide, or indium aluminum gallium arsenide or indium gallium arsenide phosphide whose lattice constant does not match that of indium phosphide. The growth temperature of the stress adjustment layer is the same as that of the quantum dots. The thickness is 0.5-20 monoatomic layers. The height of the quantum dots is controlled and the wavelength of the quantum dots is adjusted by the band gap width of the stress adjustment layer and the stress applied to the quantum dots. Then, the substrate temperature is increased to 500°C-570°C to evaporate indium. The quantum dots whose exposed height is higher than the thickness of the indium aluminum gallium arsenide layer and the stress adjustment layer are disintegrated, thereby improving the uniformity of the quantum dots. The remaining spacer layer lattice-matched to indium phosphide is then grown on the stress-modulating layer to eliminate stress accumulation and facilitate multi-layer quantum dot growth.

6. The method according to claim 4, characterized in that The growth structure of the indium arsenide quantum dot active layer in S400 is as follows: InAs quantum dots were grown between 450°C and 520°C, with a growth rate of 0.1 ML / s to 0.7 ML / s, and a ratio of group V to group III of 1 to 30; Then, one or two stress adjustment layers are grown. The stress adjustment layers are made of gallium arsenide, indium gallium arsenide, indium aluminum arsenide, or indium aluminum gallium arsenide and indium gallium arsenide phosphide whose lattice constant does not match that of indium phosphide. The growth temperature of the stress adjustment layer is the same as that of the quantum dots or is directly increased to 500°C-540°C for growth, so as to achieve dual regulation of wavelength and luminous intensity. Then the substrate temperature is increased to 500°C-570°C to evaporate the indium; A spacer layer lattice-matched to InP is then grown on the stress-modulating layer.

7. The method according to claim 5 or 6, characterized in that: S500 is specifically: A lattice-matched p-type InAlGaAs layer was grown on the multilayer quantum dots with a doping concentration of 1×10 16 cm -3 -5×10 18 cm -3 The growth temperature of the InAlGaAs layer is between 470°C and 530°C, the thickness is between 100nm and 400nm, and the ratio of Group V to Group III is greater than 25.

8. The method according to claim 7, characterized in that S600 is specifically: On the p-type InAlGaAs layer, a lattice-matched p+ InAlAs layer is grown at 470°C-530°C with a doping concentration of 5×10 17 cm -3 -2×10 19 cm -3 , thickness is 100nm – 600nm, and the ratio of group V to group III is greater than 25.

9. The method according to claim 8, characterized in that S700 is specifically: A p+ InP light confinement layer of 1000nm–2000nm is grown on the p+ InAlAs layer with a doping concentration of 1×10 18 cm -3 -2×10 19 cm -3 The growth temperature is between 470℃-530℃, and the ratio of group V to group III is greater than 25.

10. The method according to claim 9, characterized in that S800 is specifically: A p+ InGaAs contact layer is grown on the p+ InP layer at 470°C-530°C with a thickness of 100nm-400nm and a doping concentration of 1×10 18 cm -3 -2×10 19 cm -3 , among which the ratio of five ethnic groups to three ethnic groups is greater than 25.

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