CN-114628554-B - Method for preparing InGaN quantum dots, epitaxial structure and photoelectric device

CN114628554BCN 114628554 BCN114628554 BCN 114628554BCN-114628554-B

Abstract

The present disclosure provides a method of preparing InGaN quantum dots, epitaxial structures, and optoelectronic devices. The method comprises the steps of growing a GaN buffer layer on a substrate at a first temperature, raising the first temperature to a second temperature, growing an undoped GaN layer on the GaN buffer layer at the second temperature, lowering the second temperature to a set temperature, growing an InGaN quantum well layer on the undoped GaN layer, introducing NH 3 at the set temperature, continuously growing and reacting for a first time, and obtaining InGaN quantum dots on the InGaN quantum well layer, wherein the flow rate of introduced NH3 is 1-10 slm. InGaN quantum dots with different diameters and different densities are obtained through NH 3 flow change, so that the luminous performance of the InGaN quantum dots, including luminous wavelength and luminous intensity, is further optimized, and the application of the InGaN quantum dots in InGaN-based photoelectric devices is promoted.

Inventors

CHEN ZHENYU
ZHAO DEGANG
LIANG FENG
LIU ZONGSHUN
CHEN PING
YANG JING

Assignees

中国科学院半导体研究所

Dates

Publication Date: 20260512
Application Date: 20220315

Claims (7)

1. A method of making InGaN quantum dots comprising: growing a GaN buffer layer on a substrate at a first temperature; Raising the first temperature to a second temperature, and growing an undoped GaN layer on the GaN buffer layer at the second temperature; Reducing the second temperature to a set temperature, and growing an InGaN quantum well layer on the undoped GaN layer; Introducing NH 3 at the set temperature, continuously growing and reacting for the first time, and obtaining InGaN quantum dots on the InGaN quantum well layer, wherein the flow rate of the introduced NH 3 is 1-10 slm, the diameter regulation range of the InGaN quantum dots is 10-50 nm along with the change of the flow rate of NH 3 , and the density regulation range of the InGaN quantum dots is 1X 10 10 cm -2 -1X 10 11 cm -2 ; The temperature is 600-700 ℃, the thickness of the InGaN quantum well layer is 1-5 nm, the material of the InGaN quantum well layer is In x Ga 1-x N, and the In component x is 25% -50% continuously adjustable.
2. The method of fabricating an InGaN quantum dot of claim 1, comprising fabricating an InGaN quantum well layer comprising a first composition content to a first thickness such that the InGaN quantum well layer does not relax, wherein the first composition content is an In composition content of the InGaN quantum well layer, and wherein the first thickness is a thickness of the InGaN quantum well layer.
3. The method for preparing InGaN quantum dots according to claim 2, wherein the first thickness is 2-3 nm.
4. The method of making InGaN quantum dots according to claim 1, wherein the substrate material is sapphire or gallium nitride.
5. An InGaN quantum dot, characterized in that the InGaN quantum dot is prepared by the method of any one of claims 1 to 4.
6. An InGaN quantum dot epitaxial structure, characterized by comprising: A substrate; The GaN buffer layer, the undoped GaN layer, the InGaN quantum well layer and the InGaN quantum dots are sequentially epitaxial on the substrate, wherein, The InGaN quantum dot epitaxial structure is prepared by the method of any one of claims 1-4.
7. A blue-green optoelectronic device comprising the InGaN quantum dot epitaxial structure of claim 6.

Description

Method for preparing InGaN quantum dots, epitaxial structure and photoelectric device Technical Field The disclosure relates to the technical field of semiconductors, and in particular relates to a method for preparing an InGaN quantum dot, the InGaN quantum dot, an epitaxial structure and a photoelectric device. Background The GaN-based semiconductor photoelectric device is an important photoelectric device and has very wide application in ultraviolet band and visible light band. While a blue-green Light Emitting Diode (LED) and a Laser Diode (LD) have quite wide application prospects in the aspects of semiconductor illumination, laser display and the like, a conventional blue-green light emitting diode and a laser diode generally use an InGaN/GaN quantum well as an active region, and an InGaN/GaN quantum well grown on a polar surface has a severe quantum confinement stark effect, so that wave functions of electrons and holes are spatially separated, the radiation recombination efficiency of the electrons and the holes is reduced, and the quantum well luminescence is not facilitated. In particular, in the green light band, an InGaN/GaN quantum well with a higher In component is needed, and obtaining a high-quality quantum well is a necessary condition for preparing a quantum well laser diode, but the InGaN/GaN quantum well with a high In component and a high quality is still not easy to prepare at present. The conventional method for preparing InGaN quantum dots is generally complex in preparation process, difficult to control and operate, and high in preparation cost, and requires a precise process. Therefore, a new preparation method is needed to be provided, so that the InGaN quantum dots with high quality can be prepared conveniently, quickly and at low cost, and the InGaN quantum dot epitaxial structure and the photoelectric device with high quality can be obtained. Disclosure of Invention In view of the above, the present disclosure proposes a method for preparing InGaN quantum dots, epitaxial structure, and optoelectronic device. The method for preparing the InGaN quantum dots comprises the steps of growing a GaN buffer layer on a substrate at a first temperature, raising the first temperature to a second temperature, growing an undoped GaN layer on the GaN buffer layer at the second temperature, reducing the second temperature to a set temperature, growing an InGaN quantum well layer on the undoped GaN layer, introducing NH 3 at the set temperature, continuously growing and reacting for a first time, and obtaining the InGaN quantum dots on the InGaN quantum well layer, wherein the flow of introduced NH3 is 1-10 slm. Further, the method for preparing the InGaN quantum dots is set at 600-700 ℃. Further, according to the method for preparing the InGaN quantum dots, the thickness of the InGaN quantum well layer is 1-5 nm. Further, according to the method for preparing the InGaN quantum dots, the InGaN quantum well layer is made of In xGa1-x N, wherein the In component x is 25% -50% continuously adjustable. Further, the method for preparing the InGaN quantum dots comprises the steps of preparing an InGaN quantum well layer containing a first component content to reach a first thickness, so that the InGaN quantum well layer does not relax, wherein the first component content is the In component content of the InGaN quantum well layer, and the first thickness is the thickness of the InGaN quantum well layer. Further, in the method for preparing InGaN quantum dots, the first thickness is 2-3 nm. Further, according to the method for preparing the InGaN quantum dots, the substrate material is sapphire or gallium nitride. Another aspect of the present disclosure proposes an InGaN quantum dot, which is prepared by the aforementioned method for preparing an InGaN quantum dot. The invention further provides an InGaN quantum dot epitaxial structure, which comprises a substrate, a GaN buffer layer, an undoped GaN layer, an InGaN quantum well layer and an InGaN quantum dot which are sequentially epitaxial on the substrate, wherein the InGaN quantum dot epitaxial structure is prepared by the method for preparing the InGaN quantum dot. The disclosure also provides a blue-green optoelectronic device comprising the InGaN quantum dot epitaxial structure. The method has the following beneficial effects: (1) The InGaN quantum dots are directly obtained on the substrate through the growth characteristics of the InGaN layer material in the growth process, and the method has the advantages of being simple in step and easy to operate, and the process complexity for obtaining the InGaN quantum dots is remarkably reduced. (2) In the process of obtaining the InGaN quantum dots, the InGaN quantum dots with different diameters and different densities are obtained through NH 3 flow rate change, so that the luminous performance of the InGaN quantum dots, including luminous wavelength and luminous intensity, is further optimized, and