ВПЛИВ ВЛАСНОЇ ПРОВIДНОСТI НА МЕХАНIЗМИ ТЕНЗООПОРУ ОДНОВIСНО ДЕФОРМОВАНИХ МОНОКРИСТАЛIВ n-Ge

The tensoresistance for the n-Ge single crystals uniaxially deformed along the crystallographic direction [100] in the region of intrinsic conductivity is investigated. Measurements were conducted for n-Ge samples, alloyed by Sb impurity, NSb = 5 Δ 1014 cm-3 concentration. The dependence of tensoresistance at temperatures T < 330 K has three characteristic regions. For the first region (at P < 0:8 GPa), the resistivity of n-Ge does not depend on the uniaxial pressure, since at such pressures there is a lack of the deforming redistribution of electrons between the L1 and Δ1 minima. For uniaxial pressures from 0.8 to 2 GPa (second region), the growth of the resistivity of n-Ge is explained by the decrease of an effective electron mobility due to the redistribution of electrons between the L1 and Δ1 minima with different mobility. A sharp decrease of the resistivity of n-Ge at uniaxial pressures P > 2 GPa (third region) is associated with an increase in the concentration of intrinsic carriers. The reduction of the resistivity of the investigated samples of germanium at temperatures T > 330 K is explained by the growth of the intrinsic carrier concentration of current. The features of the n-Ge tensoresistance and the non-linear growth of the electron concentration for such single crystals in the range of uniaxial pressures from 0.8 to 2.4 GPa are explained by the two-band mechanism of intrinsic conduction. The conduction band of germanium under such pressures becomes (L1 - Δ1)-type. A sharp decrease in the resistivity of n-Ge at uniaxial pressures P > 2:4 GPa is associated with an increase in the magnitude of the baric coeffient of the variation of the width of the band gap at the expense of (L1 - Δ1)-type inversion of the absolute minimum in germanium. The obtained results are important in the interpretation of various kinetic effects observed in highly deformed germanium single crystals and germanium-based nanostructures. Therefore, the results can be used for the creation of high-pressure sensors, heterostructures of SiGe, quantum dots of germanium. [ABSTRACT FROM AUTHOR]