Effect of γ-irradiation on the anisotropy parameter carrier mobility in uniaxially strained n-Si crystals

Piezoresistance gamma-irradiated of various doses crystals n-Si is investigated. The profiles of the dependences were obtained in those experiments in n-Si crystals can be explained by the action of two mechanisms of specific resistance response to a change of the pressure: 1) a redistribution of charge carriers among valleys that drift under the action of a deformation in opposite directions along the energy scale; 2) an increase of the total charge carrier concentration in the C-band owing to a strain-induced reduction of the energy gap between the deep level E_c-0.17 eV and the bottom of the conduction band, which brings about a decrease of the specific resistance, as X grows. Based on the theory of anisotropic scattering and the experimental data piezoresistance is obtained of dependence anisotropy mobility parameter on uniaxially strain for these crystals. Shown that with increasing degree of compensation crystals n-Si due to increased doses irradiated necessary to consider also the scattering of charge carriers on impurity complexes or clusters, which consist of several impurity ions. Established that for n-Si irradiated with increasing dose 9,5x10¹⁷ cm^-2 of uniaxial pressure probability of this mechanism of scattering of charge carriers and decreases in strong uniaxial deformations of determining, as smaller doses would be only single scattering of ions and acoustic phonons. (authors)