A green gan-based LED epitaxial structure

Abstract

A green light GaN-based LED epitaxial structure relates to the technical field of LED epitaxial growth. The green light GaN-based LED epitaxial structure comprises a GaN core layer, a non-doped GaN layer, an n-type GaN layer, an InGaN / GaN multiple quantum well active layer and a p-type GaN layer which are sequentially grown on a stone substrate and is characterized in the InGaN / GaN multiple quantum well active layer comprises a GaN barrier layer, a first component gradient Gradedwell buffer layer, an InGaN quantum well layer, a second component gradient Gradedwell buffer layer and a variable temperature GaN transition layer. A 10mil*12mil 520-nanometer green light chip is made by using nitride epitaxial pieces grown by the method and a standard chip process, brightness of the green light chip under 20mA raises from 600mcd to 850mcd, after encapsulation, brightness of the same raises from 4.91m to 6.21m, external quantum efficiency raises from 21% to 30%, and a high-brightness green light GaN-based LED is achieved.

Description

technical field [0001] The invention relates to the technical field of LED epitaxial growth, in particular to a quantum well growth method in LED epitaxial growth. Background technique [0002] The radiation recombination efficiency is the key point of the epitaxial growth process affecting the brightness. There are many factors affecting it, such as quantum confinement effect, polarization effect, deep energy level caused by defects and impurities, which will reduce the radiation recombination efficiency. Since the quantum well InGaN material in the green epitaxial growth process requires a higher In composition (20% to 35%), which is much higher than the In composition (10% to 20%) in the blue light well, This means that lower growth temperatures are required during the growth of green light traps, which leads to poorer lattice quality and reduced performance. In addition, in the growth process of the green light well, the well and the barrier have a larger lattice differ...

AI Technical Summary

Problems solved by technology

[0002] The radiation recombination efficiency is the key point of the epitaxial growth process affecting the brightness. There are many factors affecting it, such as quantum confinement effect, polarization effect, deep energy level caused by defects and impurities, which will reduce the radiation recombination efficiency

Since the quantum well InGaN material in the green epitaxial growth process requires a higher In composition (20% to 35%), which is much higher than the In composition (10% to 20%) in the blue light well, This means that a lower growth temperature is required during the growth of the green light trap, which leads to poorer lattice quality and lower performance

In addition, in the growth process of the green light well, the well and the barrier have a larger lattice difference, which will lead to more serious lattice mismatch, more serious polarization effects, and more serious spatial separation of electron-hole wave functions Phenomenon

Therefore, compared with blue LEDs, the radiation recombination efficiency of green LEDs will decrease.

Images