The layered growth and thermoelectric properties of the Mg2Sn films

Abstract

The Mg2Sn films with layered structure of a modulation period of 0.5∼0.7 μm thickness, containing a small amount metal Mg phase, were prepared on single crystalline Si substrate using the Mg-Sn alloy target and metal Mg target by alternative magnetron sputtering. The phase composition, surface and cross-section morphology, X-ray photoelectron spectroscopy, Hall data and thermoelectric properties of the deposited Mg2Sn films were studied. The results showed that the content of metal Mg phase in deposited Mg2Sn films can be modulated by controlling single sputtering time on metal Mg target. The resistivity and Seebeck coefficient first increase and then decrease with increasing the content of metal Mg phase in deposited Mg2Sn films. The higher Seebeck coefficient and power factor can be obtained when Mg2Sn films contains a small amount of metal Mg phase. It is beneficial to an increase in both Seebeck coefficient and power factor that the deposited films have layered structure.