Hall effect and surface characterization of Cu2S and CuS films deposited by RF reactive sputtering

CuxS is one of the most prevalent minor phases co-existing in CuInS2 films. In order to understand its influence on CuInS2, we first focus our study on the binary compound CuxS. CuxS2 and CuS films were deposited on float glass substrates using a reactive RF sputter process with optimized sputter parameters, such as power, temperature of the substrate, and the gas flow of the H2S. X-ray diffraction spectra showed that the Cu2S films have (0 0 2) preferential orientation, and both compounds have a hexagonal structure. The surface morphology and the composition of the layers were analyzed by atomic force microscopy and Rutherford back-scattering spectroscopy, respectively. X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy were used to characterize the layer surfaces, as well as the-surface composition. Hall-effect measurements were carried out to determine the electrical properties of the films. (C) 2001 Elsevier Science B.V. All rights reserved.