Study on the thin films of Cu(In1 − x,Alx) Se2 prepared by selenization process

► Cu(In,Al) Se2 films were prepared by selenizing sputtered CIA precursor. ► Selenization time and temperature affected the film morphology apparently. ► Amorphous precursors transformed into chalcopyrite CIAS after selenizing. ► Resistivity of CIAS films increased with the increase of [Cu]/[In + Al] ratios. ► The films had good optical absorption properties.