Structure and properties of CIGS films based on one-stage RF-sputtering process at low substrate temperature

Currently, Nanjing South Railway Stationplanning to implement slate roof renovation is integratingsolar cell modules into traditional roof materials to generateclean energy. Copper–indium–gallium diselenide（CuIn1-xGaxSe2, CIGS） is one of the most promisingmaterials for thin film solar cells. Cu（In1-xGax）Se2 filmswere deposited by a one-step radio frequency magnetronsputtering process at low substrate temperature. X-raydiffraction, Raman, scanning electron microscopy, energydispersiveX-ray spectroscopy, and electrical and opticalmeasurements were carried out to investigate the depositedfilms. The results reveal that a temperature of 320 C iscritical for near-stoichiometric CIGS films with uniformsurface morphology. Cu-rich phase particulates are foundat less than this temperature. The sample deposited at380 C gives well-crystalline single-phase CIGS film.Furthermore, the electrical and optical performances of theabsorber layer are improved significantly with theincreasing substrate temperature.