Peculiarities of Internal Friction and Shear Modulus in 60Co γ-Rays Irradiated Monocrystalline SiGe Alloys
At present, a number of modern semiconductor devices based on SiGe alloys have been created in which the latest achievements of high technologies are used. These devices might cause significant changes to networking, computing, and space technology. In the nearest future new materials based on SiGe will be able to restrict the A3B5 and Si technologies and firmly establish themselves in medium frequency electronics. Effective realization of these prospects requires the solution of prediction and controlling of structural state and dynamical physical –mechanical properties of new SiGe materials. Based on these circumstances, a complex investigation of structural defects and structural-sensitive dynamic mechanical characteristics of SiGe alloys under different external impacts (deformation, radiation, thermal cycling) acquires great importance. Internal friction (IF) and shear modulus temperature and amplitude dependences of the monocrystalline boron-doped Si1-xGex(x≤0.05) alloys grown by Czochralski technique is studied in initial and 60Co gamma-irradiated states. In the initial samples, a set of dislocation origin relaxation processes and accompanying modulus defects are revealed in a temperature interval of 400-800 ⁰C. It is shown that after gamma-irradiation intensity of relaxation internal friction in the vicinity of 280 ⁰C increases and simultaneously activation parameters of high temperature relaxation processes reveal clear rising. It is proposed that these changes of dynamical mechanical characteristics might be caused by a decrease of the dislocation mobility in the Cottrell atmosphere enriched by the radiation defects.
 I.Kurashvili, G. Bokuchava, T. Mkheidze, I. Baratashvili. Inelastic properties of monocrystaline SiGe alloys. Bulletin of the Georgian Academy of Science, 175(4), 2007, pp. 62-65.
 I. Kurashvili, G. Darsavelidze, G. Bokuchava. Highamplitude internal friction in monocrystalline germanium-doped. J. Physica Status Solidi A, 214 (7), 2017, pp. 17001071- 17001074.
 I. Kurashvili, G. Darsavelidze, G.Bokuchava, G. Chubinidze, I. Tabatadze, G. Archuadze. Influence of Radiation Defects on Internal Friction Spectra of SiGe Crystals. Bulletin of the Georgian Academy of Science,12(3), 2018, pp. 57-61.
 I. Kurashvili, G. Darsavelidze. Mechanical relaxation processes in monocrystalline Si-Ge alloys. Proceedings of the International Conference “Advanced materials and Technology”, 2015, Tbilisi.
 I. Yonenaga, K. Sumino. Mechanical Strength and Dislocation Velocities in GeSi Alloys, Journal of Physics, III France (7), 1997, pp. 2367-2374.
 I. Yonenaga, M. Werner, M. Bartsch, U. Messerschmidt. E.R Weber. Recombination-Enhanced Dislocation Motion in SiGe and Ge, J. Physica Status Solidi 171 (a), 1999, pp. 35-40.
 I. Yonenaga Dislocation dynamics in SiGe alloys, Journal of Physics: Conference Series, (471): 2013 pp. 0120021-0120029. doi:10.1088/1742-6596/471/1/012002
 M.S. Blanter, I. Golovin, H. Neuhauser, H. Sining Internal Friction in Metallic Materials. A handbook Series: Springer Series in Materials Science 90, 2007, 539.