Yb-doped SnTe semimetal thin films deposited by thermal evaporation: Structural, electrical, and thermoelectric properties

Abstract

Sn monochalcogenide and Yb-doped Sn1−xYbxTe (0.0⩾x⩽0.1) semimetals, which are known for their usefulness as efficient thermoelectric (TE) materials, were prepared by solid-state microwave technique. Polycrystalline thin films of Sn1−xYbxTe were deposited onto clean glass substrates by using vacuum evaporation technique at 10−6bar. The structures of the polycrystalline thin films were examined by X-ray diffraction patterns. A rock salt structure was observed. Grain size increased with increasing Yb content but not according to a sequence. The morphology of the nanosheet structures for these thin films was determined by field emission scanning electron microscopy. TE properties were measured at a temperature range of 298–523K. The carrier concentrations of the films were determined by Hall effect measurements at 300K.