Structural characteristics of a non-polar ZnS layer on a ZnO buffer layer formed on a sapphire substrate by mist chemical vapor deposition

Abstract

ZnS is attractive as a material for low-cost light-emitting diodes. In this study, a non-polar ZnS layer was epitaxially grown on a sapphire substrate by inserting a ZnO buffer layer between ZnS and sapphire. The ZnS and ZnO layers were grown by a mist chemical vapor deposition system with a simple setup operated under atmospheric pressure. The sample was characterized by high-resolution X-ray diffraction measurements including 2θ/ω scans, rocking curves, and reciprocal space mapping. The results showed that an m-plane wurtzite ZnS layer grew epitaxially on an m-plane wurtzite ZnO buffer layer formed on the m-plane sapphire substrate to provide a ZnS/ZnO/sapphire structure.

Improvement of tin oxide single crystal on anm-plane sapphire substrate by mist chemical vapor deposition

“…However, the problem of lattice mismatch still exists. To overcome lattice mismatch, several methods have been reported, such as inserting a buffer layer between the film and the substrate, [38][39][40][41][42][43] changing the lattice constant of the substrate surface by doping, 44) and changing the type of solution for film formation. 39) In this study, we focused on the improvement of the crystal quality mainly in a viewpoint of FWHM in XRD rocking curve.…”