On the Nature of Radiation Resistance in Compensated Silicon

Abstract

The compensated silicon (Si ) containing carbon and germanium impurity atoms exhibits some special features (from the point of view of radiation physics) causing a modification of quasichemical impurity-defect processes in this material as compared to that without impurities. Among these special features, we mark out the following: – both impurity components are isovalent in silicon, which results in a high efficiency of states of Сs and Ges occupying lattice sites (as in well-studied А3В5 semiconductors) [1]; – Сs and Ges occupying lattice sites generate no local levels in the forbidden band [2, 3]; – due to a hierarchical ratio of the Сs, Sis, and Ges covalent radii (R) R compensated with shallow impurities naturally provide a separation of basic-defect fluxes (V and I), which simplifies an analysis and determination of the V and I contributions into the radiation effect. This work is aimed at studying the effect of the above features of quasichemical reactions in Si on the radiation resistance. We consider two cases: 1) the relative C and Ge concentrations are so low that the dipole states [Сs–Ges] are unlikely to form and 2) the C and Ge concentrations are sufficiently high, which leads to the [Сs–Ges] dipole-pair formation. We can quantitatively distinguish these two cases by introducing the radius R0 of action of elastic-deformation forces. The probability W of the event that a pair of atoms Сs and Ges is within the radius R0 of their elastic interaction is [6]