Effect of GaN buffer layers on the polarity and properties of ZnO epilayers on nitrided c‐Al₂O₃ by MBE

Abstract

. Ps, 78.55.Et, 78.40.Fy, 81.15.Hi ZnO epilayers were grown on nitrided c-Al 2 O 3 substrates by MBE and the effect of the deposition temperature for GaN buffer layers on the polarity of ZnO epilayer and their properties such as structural and optical properties were investigated. Zn-polar ZnO was normally obtained by using the low temperature GaN buffer layer at 650 ˚C, while O-polar ZnO were obtained by the high-temperature GaN buffer layer at 850 ˚C. PL spectra for Zn-polar and O-polar ZnO epilayers, PL spectra were dominated by donorbound exciton at 3.361 eV and acceptor-bound exciton at 3.356 eV, respectively. It was found that the position of emission peak was affected by the strain in the ZnO layer. PL spectra observed in ZnO epilayers with different polarities are discussed together with their reflectance spectra and strains of ZnO epilayers with different polarities.

Structural and optical properties of nearly stress-free m-plane ZnO film on (100) γ-LiAlO2 with a GaN buffer layer by metal-organic chemical vapor deposition

“…Recently, some efforts have been made on depositing non-polar GaN or ZnO films on g-LiAlO 2 (LAO) substrates for the small lattice and thermal mismatches between LAO and ZnO (GaN) [13,14]. On the other hand, GaN and ZnO can be mutually used as a buffer layer to each other for the small lattice and the thermal mismatches between them [15,16]. However, few were reported about the properties of ZnO films grown on (1 0 0) LAO with a GaN buffer layer.…”