Preparations of Cu2ZnSnS4 thin films and Cu2ZnSnS4/Si heterojunctions on silicon substrates by sputtering

The single-crystalline silicon substrate has close lattice constant with Cu2ZnSnS4 (CZTS), which is beneficial to the crystalline growth of CZTS thin films. In this work, the CZTS thin films were deposited on silicon substrates by sputtering and post-sulfurization to form CZTS/Si heterojunctions. The experimental results indicate the formation of CZTS with preferred orientation of (1 1 2) plane. The crystallinity of CZTS enhances and the secondary phases reduce with increasing sulfurization temperature. The fabricated CZTS/Si heterojunctions show rectifying and photovoltaic properties. The photovoltaic properties of CZTS/Si heterojunctions are further analyzed by the absorption of incident photons in the CZTS thin films and silicon substrates.