Cu(In1-xAlx)Se-2 thin films were deposited by one-step RF magnetron sputtering. The target was composed of mixed binary selenides of CuSe, InSe and pure aluminum powder. Smooth films surfaces with good adhesion to the substrate were grown successfully. All of the films show strong (112) and (204/220) single phase CuInSe2 peaks. Addition of A1 to the target up to 6 wt-%, at the expense of indium, shifts the orientation peaks towards higher 20 yielding films with an optical band gap between 1.05-1.7 eV For the first time, this paper reports the application of a one step sputtering deposition process to grow Cu(In1-xAlx)Se-2 thin films for solar cell absorber applications.

Keywords: solar cells; thin films; CuInSe2; sputtering; band gap