Production method of GaN-based white LED epitaxial structure

Abstract

A production method of a GaN-based white LED epitaxial structure includes the steps of preparing a monocrystalline or polycrystalline aluminum nitride buffer layer on a rare earth element doped YAG (yttrium aluminum garnet) ceramic or monocrystalline substrate by means of hydride vapor phase epitaxy; growing a GaN-based LED epitaxial structure on the monocrystalline or polycrystalline aluminum nitride buffer layer by means of metal-organic chemical vapor deposition. The GaN-based LED epitaxial structure comprises a low-temperature GaN buffer layer, a high-temperature GaN layer, an N-type GaN layer, an InGaN / GaN multiple quantum well active area, an AlGaN electronic barrier layer, a P-type GaN layer and a high-doped P-type or N-type electrode contact layer sequentially from bottom to top. The GaN-based LED epitaxial structure has the advantages that optical and physical features of fluorescent material, such as doping, thickness and quality, can be accurately controlled, integration of the fluorescent material high in repeatability and uniformity is achieved, and the problem that in traditional phosphor coating, unavailable non-uniform phosphor content occurs to the different parts of a same wafer and the different wafers due to the production process is solved.

Description

Technical field: [0001] The invention relates to the field of optoelectronic technology, in particular to a method for preparing a GaN-based white light LED epitaxial structure. Background technique: [0002] Since Nakamura and others successfully developed GaN blue LEDs in 1991, GaN-based LEDs with excellent characteristics such as high efficiency, small size, long life, and environmental protection have achieved unprecedented development and have extremely broad application prospects. Currently, white LEDs usually use blue LEDs to excite yellow phosphors to generate white light. Phosphor powder coating process can be mainly divided into three types: spraying (dispensing) process on a single packaged blue LED chip, spin coating process on the entire wafer before chip cutting, and adding remote phosphor small plate in the packaging structure technology. [0003] In the traditional spraying (dispensing) process, phosphor powder is mixed with colloid and then coated directly...

AI Technical Summary

Problems solved by technology

Since the gap between the phosphor powder and the LED chip is filled with a gas or colloid with low thermal conductivity, the heat in the phosphor material cannot be effectively dissipated through the heat sink of the LED package, which will also cause color shift of the device, decrease in luminous efficiency, and shorten the life of the device.

[0006] Therefore, there is an urgent need for a new white LED manufacturing process to solve the phenomenon of uneven phosphor material and thermal degradation, while simplifying the packaging process, improving yield, and reducing production costs.

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