Epitaxial growth method for improving luminous efficiency of LED

Abstract

The invention provides an epitaxial growth method for improving luminous efficiency of an LED. According to the method, a layer of doped n-type AlGaN barrier layer is added in a growth GaN / InGaN quantum well barrier periodic structure, an Al component gradient structure is adopted, electrons in an n area can be blocked partially, the injection kinetic energy of the electrons can be reduced, hot electrons can be captured by a potential well easily and can easily generate recombination luminescence with electron holes in a later quantum well area, and the electron overflow effect is reduced. The Al component gradient structure is adopted by a later p-type AlGaN barrier layer, growth quality of materials can be improved, and compared with a former single component structure, the gradient structure can facilitate the injection effect of the electron holes and play the function of secondary blocking.

Description

technical field [0001] The invention belongs to the technical field of LED device material preparation and structure design, and particularly relates to a new epitaxy method for growing GaN-based LEDs. Background technique [0002] The III-V semiconductor LED with GaN as the basic material has become the most promising lighting source at present. Compared with traditional lighting sources, LED semiconductor lighting sources have the advantages of high luminous efficiency, small size, long life, energy saving, environmental protection, etc. The current GaN-based LED epitaxial growth structure process is generally: first grow on a sapphire substrate A layer of low-temperature GaN buffer layer, and then grow a layer of undoped GaN at high temperature, and then grow a layer of n-type doped layer. The doping material is generally silane, which provides the electrons needed for LED compound light emission, and then grows Several cycles of GaN / InGaN quantum wells and quantum barri...

AI Technical Summary

Problems solved by technology

According to our analysis, the p-type AlGaN layer in the prior art is a single layer, and to play a good role in blocking electrons, the height of the potential barrier needs to be increased, but a higher potential barrier will also limit the injection efficiency of holes. At the same time, it is not conducive to the growth of materials, and the thickness of AlGaN must be controlled during the growth process. Too thick or too thin will have adverse effects, which will greatly affect the luminous efficiency of LEDs.

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