The Influence of Impurity Nano- and Microclusters on the Photovoltaic and Electrophysical Properties of Silicon

A comprehensive study of silicon containing nanoclusters of impurity atoms (Ni, Mn, Cr, Gd, Eu, Se) has revealed a number of unique physical phenomena uncharacteristic of classical semiconductors. It has been established that cluster structures in the silicon crystal lattice ensure the stability of electrophysical parameters over a wide temperature range and high radiation resistance to γ- and electron irradiation. It has been shown that, at Ni cluster concentrations ≥1015 cm–3, the generation of thermal donors and radiation defects is suppressed without altering the conductivity type. Impurity atoms with unfilled d- and f-shells (Mn, Cr, Gd, Eu) have been found to form ferromagnetic states in silicon, controllable by an external magnetic field at room temperature. Multicharged Mn nanoclusters were found to create localized energy levels within the forbidden bandgap, explaining the observed negative magnetoresistance and impurity absorption with an edge at 0.2 eV. For selenium-doped silicon, the possibility of creating pulse generators with frequency modulation suitable for detecting monochromatic radiation has been demonstrated. The study of binary compounds in the silicon lattice confirmed their stability and potential for developing materials with controllable photoelectric, optical, and magnetic properties.