(001)-textured Cu2S thin films deposited by RF reactive sputtering

Cu2S thin films were deposited on float glass substrates by radio frequency reactive sputtering. X-ray diffraction measurements, including grazing incidence geometry, showed that the sputtered Cu2S films had hexagonal structure with a strong (001) fiber texture. The thickness, surface density and roughness of the sputtered layers were characterized by X-ray reflectivity. Scanning electron microscopy from both top view and cross section revealed good morphology and uniform microstructure of the sputtered films. Rutherford backscattering spectroscopy and energy dispersive X-ray analysis were used to examine the composition of the films. By the optical transmission measurements, the indirect and direct band gaps of the films were estimated to be 1.19 and 1.82 eV, respectively.