Specific features of electron scattering in uniaxially deformed n-Ge single crystals in the presence of radiation defects

Abstract

ABSTRACTTemperature dependencies for concentration of electrons and the Hall mobility for unirradiated and irradiated by the flow of electrons single crystals , with the energy of , for different values of uniaxial pressures along the crystallographic directions , and are obtained on the basis of piezo-Hall effect measurements. Non-typical growth of the Hall mobility of electrons for irradiated single crystals in comparison with unirradiated with the increasing of value of uniaxial pressures along the crystallographic directions (for the entire range of the investigated temperatures) and (to temperatures ) has been revealed. Such an effect of the Hall mobility increase for uniaxially deformed single crystals is explained by the reduction of gradients of a resistance as a result of reduction in the amplitude of a large-scale potential with deformation and concentration of charged A-centers in the process of their recharge by the increasing of uniaxial pressure and consequently the probability of scattering on these centers. Theoretical calculations for temperature dependencies of the Hall mobility for uniaxially deformed single crystals in terms of the electrons scattering on the ions of shallow donors, acoustic, optical and intervalley phonons, regions of disordering and large-scale potential is good conformed to the corresponding experimental results at temperatures T<220 K for the case of uniaxial pressures along the crystallographic directions and and for temperatures when the uniaxial pressure is directed along the crystallographic directions . The mechanism of electron scattering on a charged radiation defects (which correspond to the deep energy levels of A-centers) ‘is turned off’ for the given temperatures due to the uniaxial pressure. Reduction of the Hall mobility in transition through a maximum of dependence with the increasing temperature for cases of the uniaxial deformation of the irradiated single crystals along the crystallographic directions and is explained by the deforming redistribution of electrons between the minima of conduction band of germanium with different mobility.