Composition‐ratio control of CZTS films deposited by PLD

The control of the composition of the CZTS polycrystals has been examined. CZTS poly‐crystal, ZnS, and SnS powders were mixed for adjusting the composition and were sintered at temperature of 400 °C. We evaluated polycrystal with the molar ratios of Cu/(Zn+Sn) = 0.79, Zn/Sn = 1.04, and S/(Cu+Zn+Sn) = 0.95. Then, we prepared CZTS film by PLD method using the CZTS polycrystal as a target. Composition content of the film was also evaluated to be the molar ratios of Cu/(Zn+Sn) = 1.14, Zn/Sn = 1.04, and S/(Cu+Zn+Sn) = 0.69. The film indicats slightly Cu‐rich, and S‐poor compositions, and no change of Zn/Sn rate. Definitely, we successfully performed composition control and improvement of composition uniformity for polycrystals by using the source materials of CZTS, ZnS, and SnS. Additionally, we prepared homogeneous CZTS film with either a kesterite or a stannite structure by PLD method.