Influence of growth temperature and thickness on the orientation of Cu(In,Ga)Se2 film

Abstract:

Cu(In,Ga)Se₂ (CIGS) films are deposited on the Na-free glass substrate using three-stage co-evaporation process, and the effects of thickness and growth temperature on the orientation of CIGS film are investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). When the growth of CIGS film does not experience the Cu-rich process, the increase of the growth temperature at the second stage () promotes the (112) orientation of CIGS film, and weakens the (220) orientation. Nevertheless, when the growth of CIGS film experiences Cu-rich process, the increase of significantly promotes the (220) orientation. In addition, with the thickness of CIGS film decreasing, the extent of (In,Ga)₂Se₃ (IGS) precursor orientation does not change except for the intensity of Bragg peak, yet the (220) orientation of following CIGS film is hindered, which suggests that (112) plane preferentially grows at the initial growth of CIGS film.