Growth of bismuth telluride thin films by hot wall epitaxy, thermoelectric properties

Thin films of Bi2Te3 were elaborated by HWE technique on SiO2 substrate. The films obtained are well studied by Atomic Force Microscopy (AFM) and electrical measurements such as electrical conductivity sigma, Hall coefficient R-H and Hall mobility mu(H) in the temperature range from liquid nitrogen to 570 K. The studies of their morphology by AFM shows the microstructural quality of the crystal surface. The electrical properties of Bi2Te3 thin films have been studied. It is seen that the behaviour of Hall coefficient (RH), electrical conductivity (sigma), and Hall mobility (mu(H)) are similar to the results reported for Bi2Te3 single crystals obtained by solidification process. It was obtain a optimized doping level and high carriers mobility. There results are promising for future use in the field of thermoelectric microgenerators, microcoolers or microsensors.