Evolution of interface and surface structures of ZnO$\backslash $Al2O3 multilayers upon rapid thermal annealing

ZnO$\backslash $Al2O3 multilayers were deposited on sapphires by atomic layer deposition at 85$^{\circ}$C. This low substrate temperature ensures good interface smoothness useful for study of interfacial reaction or interdiffusion. Our study aimed at the effects of rapid thermal annealing at different annealing temperatures, times and P$_{\mathrm{Ar}}$:P$_{\mathrm{O2}}$. XRR and XRD techniques were used to investigate the kinetics from which various terms of the activation energies could be determined. HR-TEM and electron diffraction were carried out to correlate the microstructures and interfacial alignments as a result of the reactions. AFM were used to assist SEM profiling of the surface morphological evolution in association with the TEM observations.