TRANSPORT-PROPERTIES OF FLASH-EVAPORATED (BI1-XSBX)2TE3 FILMS .1. OPTIMIZATION OF FILM PROPERTIES

Bi0.5Sb1.5Te3 films were deposited by flash evaporation on silicon wafers with thermally grown SiO2 overlayers (SiO2/Si substrates). Their transport properties, i.e. the electrical conductivity, Hall coefficient, magnetoresistance coefficient, Hall mobility, Seebeck coefficient, thermal conductivity and thermoelectric figure of merit, were determined in the temperature range from 80 to 400 K. Investigations concerning the annealing behaviour in an argon atmosphere were carried out on films without and with protective layers. By optimization of manufacturing conditions, it was possible to obtain films of a high Hall mobility and with a thermoelectric figure z of merit of 2.9 × 10-3 K-1 at room temperature. Since photolithographic structurization is possible these films will be useful as p-type materials for many applications in thermoelectric thin film devices in combination with microelectronic circuits on SiO2/Si wafers. © 1990.