Mechanisms of electron scattering in uniaxially deformed n\textit{n}-Ge⟨Sb, Au⟩\text{Ge} \langle \text{Sb, Au}\rangle single crystals

Temperature dependencies for concentration and the Hall mobility of electrons for the $\textit{n}$-$\text{Ge} \langle \text{Sb}\rangle$ and \linebreak $\textit{n}$-$\text{Ge} \langle \text{Sb, Au}\rangle$ single crystals uniaxially deformed along the crystallographic directions [100] and [111] are obtained on the basis of piezo-Hall effect measurements. A deformation-induced increase of the Hall mobility of electrons for $\textit{n}$-$\text{Ge} \langle \text{Sb, Au}\rangle$ single crystals at the uniaxial pressure along the crystallographic direction [100] has been revealed. A comparison of the obtained experimental results with the corresponding theoretical calculations of temperature dependencies of the Hall mobility showed that the obtained effect occurs at the expense of the reduction probability of electron scattering on the fluctuational potential. Its amplitude depends on the tempe\-rature and on the value of the uniaxial pressure. It has also been shown that an increase of the Hall mobility for the $\textit{n}$-$\text{Ge} \langle \text{Sb, Au}\rangle$ single crystals uniaxially deformed along the crystallographic direction [111] with an increasing temperature turns out to be insignificant and is observed only for the uniaxial pressures $P<0.28$ GPa. A decrease of the Hall mobility of electrons at the expense of the deformational redistribution of electrons among the valleys of the germanium conduction band with different mobility should be taken into account in the present case. The Hall mobility magnitude for the uniaxially deformed $\textit{n}$-$\text{Ge} \langle \text{Sb}\rangle$ single crystals is determined only by the mechanisms of phonon scattering and we have not observed the effect of the growth of the Hall mobility with an increase of temperature or the magnitude of uniaxial pressure.Comment: 10 pages, 7 figure

Radiation defects parameters determination in n-Ge single crystals irradiated by high-energy electrons

Hall effect for single crystals of n-Ge, irradiated by various streams of electrons with an energy of 10 MeV is investigated. Taking into account the experimental results, the energy spectrum of radiation defects is found and their parameters are established. On the basis of solutions of electroneutrality equations systems, it is shown that the created radiation defects correspond to only two deep energy levels (Ec - 0.27) eV and (Ec + 0.27) eV. A slight change of energy position of these levels with irradiation dose increasing can be explained by internal mechanical stresses influence that arise in the germanium lattice around created radiation defects

Determination of the activation energy of A-center in the uniaxially deformed n-Ge single crystals

Based on the decisions of electroneutrality equation and experimental results of measurements of the piezo-Hall-effect the dependences of activation energy of the deep level A-center depending on the uniaxial pressure along the crystallographic directions [100], [110] and [111] for n-Ge single crystals, irradiated by the electrons with energy 10 MeV are obtained. Using the method of least squares approximational polynomials for the calculation of these dependences are obtained. It is shown that the activation energy of A-center deep level decreases linearly for the entire range of uniaxial pressure along the crystallographic direction [100]. For the cases of uniaxial deformation along the crystallographic directions [110] and [111] decrease of the activation energy according to the linear law is observed only at high uniaxial pressures, when the A-center deep level interacts with the minima of the germanium conduction band, which proved the lower at the deformation. The various dependences of the activation energy of A-center depending on the orientation of the axis of deformation may be connected with features of its microstructure