Journal of Physical Studies 19(1/2), Article 1701 [3 pages] (2015) DOI: https://doi.org/10.30970/jps.19.1701 ACTIVATION ENERGIES OF TECHNOLOGICAL TERMODONORS IN NEUTRON DOPED SILICON L. I. Panasjuk, V. V. Kolomoets, V. N. Ermakov, S. A. Fedosov, L. V. Yashchynskiy 1Institute of Semiconductor Physics, National Academy of Sciences of Ukraine, 45, Nauky Ave., Kyiv, UA-03028, Ukraine, e-mail: ekol@isp.kiev.ua 2Lesya Ukrainka Eastern European National University, Solid-State Physics Departament, 13, Voli Ave., Lutsk, UA-43000, Ukraine 3Lutsk National Technical University, Physics and electrical Departament, 75, Lvivska St., Lutsk, UA-43018, Ukraine

The typical pressure dependence of resistivity in uncompensated $n$-Si crystals doped by phosphorus from the melt is characterized by the saturation of resistivity at uniaxial pressure $X\simeq 0.7$ GPa. This peculiarity is determined by the Smith-Herring's dominant mechanism of TR which is defined by the redistribution of $c$-band electrons between the $\Delta_1$-minima when $X \parallel [001]$ increases. On the contrary, the pressure dependencies of resistivity in NTD $n$-Si(P) crystals are characterized by both maximum availability on the resistivity dependencies at $X\simeq 0.6$ GPa and the following exponential-shape decreasing of resistivity in the pressure range $0.6\div 1.2$ GPa. We attribute the above mentioned exponential resistivity decreasing in NTD $n$-Si(P) to the strain-induced ionization of technological TDs energy states.

To achieve the acceptable precision of the determination of the activation energy of high-temperature technological thermal donors the Hall effect was studied in the high-purity ($N_{\rm P}<10^{13}$\,cm$^{-3}$) transmutation doped silicon crystals. Cobsidering that the phosphorus impurity is completely ionized already at $T=78$\,K, the variation of free electrons concentration with the increasing temperature in the range (78-300\,K) is shown to be caused by a thermal ionization of technological donors.

Based on the analysis of Hall's results the activation energy of thermal donors was found. The temperature dependence of the Hall coefficient shows the presence of two levels $\varepsilon_1 = 72.5\pm 1.0$\,меВ and $\varepsilon_2 = 257$\,меВ. These are the activation energies of thermal donors formed under the annealing of the transmutation doped Czochralski-grown silicon.

PACS number(s): 72.20.Fr

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