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

We fabricated Cu2SnSe3 thin film on a Mo-coated soda-lime glass substrate by a co-evaporation method. The X-ray 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.