Preferred orientation and interdiffusion in zinc oxide/copper oxide multilayered films

Abstract

ZnO/CuO and ZnO/ZnOCuO/CuO multilayered films were deposited on Pyrex substrates at <100°C by ion-beam sputtering. The preferred orientation and interdiffusion of these films were examined for films with varying layer repeat lengths (pair thickness). X-ray diffraction analysis showed a preferred ZnO (0 0 2) orientation parallel to the surface in annealed ZnO layers of --~ 1 to --~ 3 nm thickness; no peak was observed for films with a layer repeat length smaller than 1.1 nm. The degree of preferred orientation reduced with increasing layer thickness in ZnO/CuO films and with increasing ZnOCuO thickness in ZnO/ZnOCuO/CuO films. The decay rate of the low-angle X-ray intensity showed that interdiffusivity is largely dependent on the layer repeat length. A smaller layer repeat length gave a larger value of interdiffusivity.