GaN-based light-emitting diode epitaxial wafer and preparation method thereof

Abstract

The invention discloses a GaN-based light-emitting diode epitaxial wafer and a preparation method thereof, and belongs to the field of GaN-based light-emitting diodes. The method includes the steps of: providing a substrate; depositing a buffer layer on the substrate, the buffer layer comprising a plurality of stacked composite layers, each composite layer comprising an AlN sub-layer and an AlNO sub-layer, the oxygen content of the AlNO sub layer in each composite layer is gradually increased from a composite layer being closet to the substrate to a composite layer being farthest to the substrate; and depositing an undoped GaN layer, an N-doped GaN layer, a quantum well layer, an electron blocking layer, a P-type GaN layer and a P-type contact layer on the buffer layer in order.

Description

technical field [0001] The invention relates to the field of GaN-based light-emitting diodes, in particular to a GaN-based light-emitting diode epitaxial wafer and a preparation method thereof. Background technique [0002] A GaN (gallium nitride)-based LED (Light Emitting Diode, light emitting diode) generally includes an epitaxial wafer and electrodes prepared on the epitaxial wafer. The epitaxial wafer usually includes: a substrate, and a GaN-based epitaxial layer grown on the substrate. The epitaxial layer includes a sequentially stacked buffer layer, a non-doped GaN layer, an N-type GaN layer, and an MQW (Multiple Quantum Well, multiple quantum well ) layer, electron blocking layer, P-type GaN layer and contact layer. When a current is injected into the GaN-based LED, the electrons in the N-type region such as the N-type GaN layer and the holes in the P-type region such as the P-type GaN layer enter the MQW active region and recombine to emit visible light. Wherein, t...

AI Technical Summary

Problems solved by technology

[0003] In the process of realizing the present invention, the inventors have found that the prior art has at least the following problems: when the buffer layer is an AlN buffer layer, there is a relatively large compressive stress between the AlN and GaN, which will cause large warping of the epitaxial wafer. Curvature, the wavelength of the epitaxial wafer manifests as a bulge in the center and diffuses to the edge of the epitaxial wafer in the form of concentric circles, resulting in poor wavelength uniformity of the epitaxial wafer

Images