Growth of CZTS Thin Films by Cosputtering of Metal Targets and Sulfurization in H2S

Copper zinc tin sulfide (CZTS) is an emerging thin film photovoltaic material. Chemical composition and phase purity are important factors which decide the quality of the film for photovoltaic applications. In the present work, we report the results of the morphological, structural, optical, and electrical characterizations of Cu2ZnSnS4thin films, synthesized by sulfurizing magnetron cosputtered Cu2ZnSn thin films in ambient H2S. To the best of our knowledge, this is the first report on CZT deposition by cosputtering from Cu, Zn, and Sn targets and sulfurizing it in ambient H2S for making CZTS thin films. GIXRD and Raman study results showed that the film was kesterite CZTS. Optical absorbance studies revealed a band gap value of ~1.5 eV for CZTS thin film. Results of the Hall effect measurements are also reported.