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The room-temperature dependences of the Seebeck coefficient, Hall coefficient, electrical conductivity, charge carrier mobility, and thermoelectric power factor were obtained as a function of thickness d (d = 8 nm to 400 nm) of PbTe epitaxial layers grown by thermal evaporation in vacuum of PbTe polycrystals doped with Na onto (100)KCl surfaces and covered with an Al 2 O 3 layer. Distinct oscillations in the d-dependences of the properties were observed and attributed to the size quantization of the energy spectra in PbTe layers. The experimental values of the oscillation period are in good agreement with the results of theoretical calculations using the effective-mass approximation and a model for a rectangular potential well with infinitely high walls. It follows from the obtained results that quantization of the energy spectrum in PbTe thin-film structures occurs not only for the electron gas but also for the hole gas.

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Studies of the concentration (0–3 mol% PbSe) and temperature (250–670 K) dependences of the lattice thermal conductivity λp in PbTe–PbSe semiconductor solid solutions have shown that in the range of 0.75–1.25 mol% PbSe an anomalous increase in λp under increasing PbSe concentration takes place in the λp isotherms, plotted as λp/λp0, where λp0 is the lattice thermal conductivity in the absence of PbSe. The observed effect is attributed to critical phenomena and self‐organization processes accompanying the transition from dilute solid solutions to an impurity continuum.

The influence of Bi, introduced in the elementary form in the stoichiometric lead telluride, on the thermoelectric properties of PbTe crystals and thin films prepared by thermal evaporation in vacuum and deposition onto mica substrates was studied. The temperature dependences of the Hall coefficient, the Seebeck coefficient, electrical conductivity, charge carrier concentration, and charge carrier mobility were obtained in the range 77-300 K for the crystals and thin films. On the basis of them, the dependences of the properties on Bi concentration at fixed temperatures were plotted. The isotherms of the properties have non-monotonic character, which is attributed to the complex processes of the defect formation, taking place under introduction of the elementary Bi in PbTe. The behavior of the isotherms of the properties practically does not change with changing temperature. The correlation between Bi concentration in PbTe charge and the thermoelectric properties of the thin films was established, which gives the possibility to control thermoelectric properties of thin films by changing the charge composition. The Bi concentrations corresponding to the maximum values of thermoelectric power factor of the crystals and thin films were determined.

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