Synthesis of SnS thin films via high vacuum sulfidation of sputtered Sn thin films

Abstract

In this letter, a new approach for the synthesis of SnS thin films is introduced. In this approach, Sn thin films were first deposited on glass substrates by r.f. magnetron sputtering under forming gas (95% Ar+ %5 H2) atmosphere and post-sulfidation of the sputtered Sn thin films was performed under high vacuum (<10−5Torr). Due to low pressure, complete sulphurisation of Sn thin films via diffusion of evaporated S atoms took place at a relatively lower temperature. For a 400nm Sn thin film, 250°C and 150min were determined as the optimum sulfidation temperature and time to obtain orthorhombic SnS thin film. It has been determined that while short sulfidation time (<120min) leads to residual metallic Sn, high sulfidation temperature (>250°C) induces SnS2 formation.