Composition-Dependent Characterization of Sb2Te3 Thin Films Prepared by Ion Beam Sputtering Deposition

Abstract

The optimization of ion beam sputtering deposition process for Sb2Te3 thin films deposited on BK7 glass substrates is reported. The influence of composition ratio on the thermoelectric properties is investigated. X-ray diffraction shows that the major diffraction peaks of the films match with those of Sb2Te3. Hall effect and Seebeck coefficient measurement reveal that all the samples are of p-type. The Sb2Te3 thin films exhibit the Seebeck coefficient of 190 μVk−1 and the electrical conductivity of 1.1 × 103 Scm−1 when the atomic ratio of Sb to Te is 0.65. Carrier concentration and motility of the films increase with the increasing atomic ratio of Sb to Te. The Sb2Te3, film with a maximum power factor of 2.26 × 10−3 Wm−1K−2 is achieved when annealed at 400° C. Raman measurement shows that the main peaks are at about 120 cm−1, 252 cm−1 and 450 cm−1, in agreement with those of V-VI compound semiconductors.