An investigation was made of the dependence of individual 60' and screw dislocation velocities on stress, temperature, and impurity (B, As, Sb) concentration in silicon single crystals. It was found that both donor and acceptor impurities result in decrease of the activation energy ( U ) of the dislocation motion. The donor influence on U is stronger.The possible reasons for the observed phenomenon are analysed in terms of the effect of impurities on the mechanism of overcoming of Peierls stresses b y a dislocation.

Bulk nanostructured polycrystals are prospective thermoelectrics. Fabrication and examination of nanostructured polycrystalline p-Bi-Sb-Te are discussed. The influence of fabrication conditions and the composition of the material on sizes of nanograins was investigated experimentally. Basic physical properties of fabricated nanothermoelectrics including nanocomposites were also studied. Theoretical estimation of the influence of phonon scattering on nanograin boundaries in bulk nanostructured thermoelectrics is presented.

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