Optimization in fabricating bismuth telluride thin films by ion beam sputtering deposition

► Stoichiometric Bi2Te3 thermoelectric thin films are achieved by ion beam sputtering. ► The films have single Bi2Te3 phase and preferential orientation along the c-axis. ► The films have high thermoelectric properties comparable with others best results. ► High quality Bi2Te3 films must be deposited at appropriate substrate temperature.