Method for epitaxially growing large chamfering angle sapphire substrate-based GaN and application of GaN

Abstract

The invention provides a method for epitaxially growing large chamfering angle sapphire substrate-based GaN. The method comprises the steps of S1, placing a large chamfering angle sapphire substrate with a chamfering angle larger than 0.2 degree in an epitaxial growth device, and sequentially growing a nucleating layer ,an unintentionally-doped GaN layer and a first layer of n-type GaN on the large chamfering angle sapphire substrate in a lamination way; and S2, introducing NH3 and trimethyl gallium into the epitaxial growth device, controlling the flowing ratio of the NH3 and the trimethyl gallium to be larger than 600, and simultaneously controlling chamber pressure of the epitaxial growth device to be smaller than 400mbar so that a second layer of n-type GaN is grown on the first layerof n-type GaN at a speed larger than 0.5 nanometer per second and a large chamfering angle sapphire substrate-GaN composite structure is obtained. By optimizing a growth process, high-quality GaN is epitaxially grown on the large chamfering angle sapphire substrate, so that grown on a template of the large chamfering angle sapphire substrate-GaN composite structure can be performed to obtain a high-quality green-light or yellow-light waveband InGaN quantum well.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, and specifically relates to a method for epitaxially growing gallium nitride on a sapphire substrate with a large off-cut angle and its application. Background technique [0002] The sapphire substrate is a commonly used substrate in the current LED (light emitting diode) or LD (laser diode) industry. It is cheap and has mature technology. Compared with the expensive GaN self-supporting substrate, it is more widely used. By epitaxially growing a section of GaN on a sapphire substrate, a GaN substrate that can be used for InGaN growth is obtained. This sapphire-gallium nitride composite structure is called a template, which can be used for subsequent light-emitting device fabrication. The template obtained by growing GaN epitaxially on the bottom is an indispensable technology in the LED and LD industries. [0003] In addition, InGaN is the core material that constitutes the quantum wells ...

AI Technical Summary

Problems solved by technology

However, the bevel angle of the current commercial sapphire substrate is generally 0.2°, because a larger bevel angle will cause serious step aggregation of GaN grown on it, which will affect its use.

Therefore, the current GaN growth process is optimized for small bevel angle (0.2°) sapphire substrates, and the crystal quality of InGaN grown on small bevel angles is not high, and the luminous intensity and half width are not good.

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