Enhanced thermoelectric properties and layered structure of Sb2Te3 films induced by special (0Â 0Â l) crystal plane

In this Letter, special (0 0 l) crystal plane and uniquely alternate stress field can favorably influence the carrier and phonon transport properties of layered films. The oriented p-Sb2Te3 layered films have been successfully fabricated by the simple magnetron co-sputtering method. The measurement results show that the layered Sb2Te3 films with each layer ∼40 nm are (0 0 l)-preferential orientation. The highly (0 0 l)-oriented Sb2Te3 layered film with a thermoelectric dimensionless figure-of-merit ZT = 1.22 was obtained at room temperature. The in-plane transport mechanism of layered structure is proposed and investigated. Introduction of such preferential (0 0 l) crystal plane and uniquely alternate stress field into TE films is therefore a very promising approach.