In situ growth regime characterization of cubic GaN using reflection high energy electron diffraction

TL;DR

This study uses in situ reflection high energy electron diffraction to analyze the growth conditions of cubic GaN layers, identifying optimal Ga coverage for high-quality epitaxial growth.

Contribution

It introduces a quantitative in situ method to determine Ga coverage during cubic GaN growth, optimizing growth conditions for improved surface quality.

Findings

Optimal growth at 1 ML Ga coverage.

Achieved surface roughness of 2.5 nm.

Minimized FWHM of (002) rocking curve.

Abstract

Cubic GaN layers were grown by plasma-assisted molecular beam epitaxy on 3C-SiC (001)substrates. In situ reflection high energy electron diffraction was used to quantitatively determine the Ga coverage of the GaN surface during growth. Using the intensity of the electron beam as a probe,optimum growth conditions of c-GaN were found when a 1 ML Ga coverage is formed at the surface. 1 micrometer thick c-GaN layers had a minimum surface roughness of 2.5 nm when a Ga coverage of 1 ML was established during growth. These samples revealed also a minimum full width at half maximum of the (002)rocking curve.