Crystallinity of In2O3(ZnO)5 films by epitaxial growth with a self-buffer-layer

Naturally modulated structures, films of In2O3(ZnO)(5), were epitaxially grown by rf magnetron sputtering on (0001) sapphire substrates. The crystallographic and morphological features of the films were characterized by using x-ray-diffraction and electron-diffraction patterns. The deposition of strongly c axis orientated films of In2Zn5O8 was achieved by epitaxy with a self-buffer layer (SBL). A film of In2Zn5O8 of approximately 10 nm in thickness was initially deposited as the SBL. This initial film was annealed in situ for 10-15 min, after which the bulk of the film of In2Zn5O8 was grown. Finally, well-crystallized In2O3(ZnO)(5) films were obtained by annealing the resultant film at 800 degreesC. The electrical properties of the synthesized film are discussed in relation to the mechanism by which the modulated In2O3(ZnO)(5) structure is formed. (C) 2002 American Institute of Physics.