Pressure-dependent Raman scattering of co-evaporated Cu2ZnSnSe4 thin film

Abstract

We obtained Raman spectra of a co-evaporated Cu2ZnSnSe4 (CZTSe) thin film under pressures of up to 5.56 GPa using a gasketed diamond anvil cell. Each spectrum was carefully resolved into Lorentzian peaks to analyze the observed phonons. Six Raman peaks were observed at 1 atm. These Raman peaks appeared at 174, 193, 196, 220, 234, and 248 cm(-1) and were attributed to the vibration modes of kesterite CZTSe with B (or A), E, A, E, B, and B symmetries, respectively. Also, two Raman modes with a frequency of approximately 260 cm(-1) emerged at 1.27 GPa. A small additional peak with a 220 cm(-1) Raman shift was visible at pressures higher than 3.55 GPa. The origins of these peaks are also discussed. (C) 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim