No abstract

Cu2ZnSnSe4 (CZTSe) thin films were prepared by the simple process of selenization of single-layered metallic Cu-Zn-Sn precursors. These metallic precursors were deposited by radio frequency magnetron sputtering of a ternary Cu-Zn-Sn alloy target. Successive selenization was performed at various temperatures between 250°C and 500°C for 30 min. X-ray diffraction and Raman analysis showed that a single phase of the CZTSe compound can be obtained by selenization at 400°C, while increasing the selenization temperature to 500°C improves the grain size and crystal quality. The direct optical band gap of CZTSe films was calculated to be 1.06 eV to 1.09 eV with a high absorption coefficient on the order of 10 4 cm -1 for samples selenized at 400°C to 500°C. The obtained films are p-type semiconductors with bulk carrier concentrations of 2.41 to 7.96 × 10 18 cm 3 , mobilities of 1.30 cm 2 V -1 s -1 to 9.27 cm 2 V -1 s -1 , and resistivities of 0.20 Ωcm to 1.95 Ωcm.