High pressure Raman scattering of a co-evaporated Cu2SnSe3 thin film

Abstract

We fabricated Cu2SnSe3 thin film on a Mo-coated soda-lime glass substrate by a co-evaporation method. The Xray diffraction pattern revealed the formation of polycrystalline Cu2SnSe3 with a monoclinic structure (space group Cc). Raman scattering measurements were also performed on the thin film at a pressure ranging from 1 atm to 7.01 GPa. The Raman spectrum was resolved into 4 Lorentzian peaks observed at 184 cm(-1), 206 cm(-1,) 236 cm(-1), and 252 cm(-1) at 1 atm, which correspond to A', A", A", and A' symmetry, respectively. The effects of pressure on these Raman-active phonon modes were discussed. The measured elastic properties of Cu2SnSe3 under high pressure were also compared with those of Cu2ZnSnSe4.