High-quality GaN grown on stainless steel substrate with Al2O3 buffer via plasma-enhanced atomic layer deposition

Abstract

Gallium nitride (GaN) thin films were grown on stainless steel substrate with Al2O3 buffer by plasma-enhanced atomic layer deposition. The GaN and Al2O3 are all deposited at low temperature (≤290 ℃). The morphology, structural and optical properties of the GaN were investigated. The grazing incidence X-ray diffraction result manifests the as-deposited GaN is polycrystalline with a strong (002) preferential orientation. Through Spectroscopic Ellipsometry, the refractive index of the films is determined as 2.30 at 633 nm. The results indicate the high-quality GaN was grown on stainless steel. This study provides a new approach to achieve high-quality GaN grown on metal substrates, which is quite promising for future applications of GaN-based devices on metal substrates.