High-temperature growth of ZnSnN₂ layer via radiofrequency magnetron sputter epitaxy

ZnSnN 2 layers were grown directly on Al 2 O 3 (0001) substrates via RF magnetron sputter epitaxy at various substrate temperatures using N 2 gas and a ZnSn alloy target. The crystalline quality and surface morphology of the ZnSnN 2 layers were examined. X-ray diffraction patterns indicated that ZnSnN 2 layers grown at substrate temperatures of 600 °C and 700 °C had wurtzite-type structures. The gross full width at half maximum (FWHM) value of the X-ray rocking curve (XRC) for the (0002) plane of the ZnSnN 2 layer grown at 700 °C was 324 arcsec. The XRC for the (0002) plane contained two components, and the FWHM values of these components were 206 and 1520 arcsec for the highly c -axis-oriented columnar domains and disordered structure inside the ZnSnN 2 layer, respectively. Metallic Sn was detected in a ZnSnN 2 layer grown at 800 °C.