Thermoelectric Power Studies on 1% Excess Te Doped Pb_0.8Sn_0.2Te Thin Films

Abstract

Thin films of Pb0.8Sn0.2Te of thicknesses varying between 360 Å and 3400 Å have been prepared by flash evaporation on cleaned glass substrates held at room temperature. Thermoelectric power (TEP) of these films has been evaluated by measuring the thermal emf developed by the integral method in the temperature range 300 K to 500 K. It has been found that TEP of all the films is positive and increases with temperature in the low temperature region and tends to saturate at high temperatures, beyond 400 K. This has been attributed to the pinning of the Fermi level at high temperatures. It was also found that these films did not show the expected linear dependence of TEP on the inverse film thickness.

Hysteresis-like behaviour of the thermoelectric voltage in photovoltaic materials

“…Very convincing results were published by Trousil [5] when very large values of DT (å 100 K) were established along Ge samples. Under similar conditions (large DT values), the sample (Pb 0.8 Sn 0.2 Te) annealing, induced during its heating (increasing DT), gives place to a non-linear V vs. DT response [6]. But, once the sample is completely annealed, this non-linear response disappears and, in fact, a linear response is obtained on decreasing DT.…”

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

“…[3][4][5][6][7] There are only a few reports on thermoelectric properties of thin films of this material. [8][9][10] In the present work, we have chosen the alloy Pb 0.6 Sn 0.4 Te from Pb 1Ϫx Sn x Te (0рxр1) system to study the feasibility of thin films of this material for thermoelectric applications. The electrical resistivity and thermoelectric power measurements have been carried out on flash evaporated thin films as a function of their thickness and temperature.…”