LOW-TEMPERATURE EPITAXIAL-GROWTH OF ALN THIN-FILMS ON AL2O3(0001) BY REACTIVE DC FACED MAGNETRON SPUTTERING

In this paper we report the high quality epitaxial AIN thin films have been grown on basal plane sapphire substrates [Al2O3(0001)] at low te mperatures (300, 500 degrees C) by reactive de faced magnetron sputter ing. From UV-VIS spectroscopy, refractive index of n = 2.07 at 632.8 n m and absorption edge at 198 nm were obtained. The epitaxial AlN films , characterized by four-circle XRD . studies, have the following epita xial relationship with respect to the sapphire substrate: for out of p lane, AlN(0001)//Al2O3(0001), and for in-plane alignment, AlN(10 (1) o ver bar)//Al2O3(11 (2) over bar 0). Also, XRD revealed that the stress , caused by lattice misfit, affected internal plane disarrangement.