Nitride epitaxial growth technology adopting AlON buffer layer

Abstract

The invention provides a nitride epitaxial growth technology adopting an AlON buffer layer. The technology comprises the following steps: providing a substrate; forming an aluminium nitride polycrystalline film on the substrate; performing thermal oxidation treatment on the aluminium nitride polycrystalline film so as to form an aluminum oxynitride polycrystalline layer; performing expitaxial growth of nitride on the aluminum oxynitride polycrystalline layer which serves as the buffer layer. The technology has the advantages that aluminum oxynitride has a favorable lattice mismatch relaxation effect, can alleviate the lattice mismatch and thermal expansion coefficient mismatch of semiconductor materials for growing the nitrides and reduce stress; a flexible strain covariation layer is formed, so that the stress between an epitaxial layer and the substrate is flexibly buffered, and a crystal film with low dislocation density and high crystal quality can be obtained. The technology is compatible with an existing semiconductor technology and is good in repeatability and beneficial to large-scale production; meanwhile, aluminum oxynitride has favorable thermal and chemical stability, is less in possibility of interfacial reaction with the substrate and the epitaxial layer, and is capable of avoiding impurity contamination of the epitaxial layer.

Description

technical field [0001] The invention relates to the field of semiconductor epitaxy, in particular to a nitride epitaxial growth technology using an AlON buffer layer. Background technique [0002] Gallium nitride and its alloy semiconductors are the core basic materials for the preparation of optoelectronic devices used in ultraviolet / blue / green light-emitting diodes, lasers, and detectors. It has broad application prospects in the fields of high-rate transistors and power electronic devices. [0003] At present, the single crystal substrate preparation technology of gallium nitride or aluminum nitride is not yet mature, so the nitride is usually heteroepitaxially grown on substrates of other materials such as sapphire, silicon carbide, silicon, etc. Due to the differences in lattice and thermal expansion coefficients and the influence of interfacial chemistry issues, buffer layers are usually required to relieve stress and improve crystal quality. Especially for silicon s...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to provide a kind of epitaxial growth technology of nitrides using AlON buffer layer and the nitrides epitaxially grown by this method, which can alleviate problems such as lattice mismatch and thermal mismatch, and is flexible. The stress between the epitaxial layer and the substrate is effectively buffered, and a crystal film with low dislocation density and high crystal quality can be obtained

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