Thickness and temperature effects on thermoelectric properties of Pb0.6Sn0.4Te thin films

Electrical resistivity and thermoelectric power measurements have been carried out as a function of thickness in the temperature range 300-480 K on flash evaporated Pb0.6Sn0.4Te thin films. Electrical resistivity and thermoelectric power variation with temperature of the films suggests that they have a near-degenerate semiconductor behavior. The effective mean-free-path model of classical size effect has been used to analyze the thickness dependence of resistivity and thermoelectric power. Both are found to be near-linear functions of inverse thickness. From the analysis of the experimental data, material parameters like mean free path and Fermi energy have been evaluated. Thermoelectric figure of merit has been calculated using the measured values of thermoelectric power and electrical resistivity and by taking thermal conductivity data from the literature. Thermoelectric figure of merit is also found to be thickness and temperature dependent. (C) 1996 American Institute of Physics.