Epitaxial growth of InN thin films by plasma-enhanced atomic layer deposition

Abstract

In this study, we report on the growth of crystalline InN thin films by plasma-enhanced atomic layer deposition (PE-ALD). By systematically investigating the growth parameters, we determined the process window for crystalline InN films growth by PE-ALD. Under the optimal conditions, we compared Si (100), Al2O3 (0001), and ZnO (0001) substrates with different lattice mismatches to InN. High resolution X-ray diffraction (HR-XRD) measurements showed that we obtained the epitaxial InN thin film on the ZnO (0001) substrate, which has the smallest lattice mismatch. The crystal orientation relationship is found to be InN[0001]∥ZnO[0001] and InN[10−10]∥ZnO[10−10]. HR-XRD and high resolution transmission electron microscopy measurements revealed that the InN films are fully relaxed, and no voids or interlayer is observed at the interface. Our results show that the epitaxial growth of the InN film can be obtained by PE-ALD at low temperature.