Effects of GaN template on atomic‐layer‐epitaxy growth of ZnO

ZnO layer was epitaxially grown on GaN template by atomic layer epitaxy (ALE) using Diethylzinc (DEZ) and H2O at the growth temperature of 250 °C. By reflection high-energy electron diffraction (RHEED) measurements, spotty pattern was observed for the ZnO layer directly grown on c-plane sapphire substrate, while streaky pattern was observed for that grown on GaN template. Full-width at half-maximum (FWHM) value of (0002) X-ray rocking curve of ZnO layer was greatly reduced from 4.96° to 0.103° by using GaN template. By photoluminescence (PL) measurements, only the near bandedge emissions were observed. FWHM of the neutral-donor-bound-exciton (D0X) emission line was reduced from 18.7 to 16.1 meV by using GaN template. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)