LAUSR

Abstract Tin sulphide (SnS) thin films have been grown by Chemical Bath Deposition (CBD) and annealed up to 600 °C. Non-intentionally doped films show p-type conduction which makes them an ideal partner material for p-n type photovoltaic devices. Most of the films were modestly Ga-doped, but addition of other elements like Fe, Cu, and In was also investigated. We studied essential optoelectronic material parameters like band gap, Urbach tail parameter, and optical absorption using transmission measurements. We found marked differences in the composition of the film surface and of the bulk region. Such complementary results were possible through X-ray photoelectron spectroscopy (XPS) and Rutherford backscattering analysis (RBS), respectively. A tentative model of surface modification and diffusion barrier formation based on thermodynamic arguments is given. Emphasis is put on the study of kinetics of photoinduced carriers after high-power laser pulses by contactless Microwave Transient Reflection (MWTR) analysis. The MWTR signal intensity is increasing strongly upon thermal annealing from 200 to 600 °C, reflecting the strongly improved photoactivity.