Self-interstitial shallow-donor complexes in silicon: An electron-paramagnetic-resonance study

Abstract

An electron-paramagnetic-resonance (EPR) study on silicon samples quenched after diffusion of gold (or platinum) from a metallic layer on the surface results in the presence of two types of paramagnetic centers replacing the donor P center. According to the analysis these centers consist of a P donor with a self-interstitial in either the nearest-neighbor (NN) or next-nearest-neighbor (NNN) position. This result supports the early assumption that large amounts of self-interstitials are produced by such a treatment. P (or As) impurities act as stabilizing entities. This is verified by a modified donor hyperfine interaction which exhibits a strong temperature dependence. The results are explained by strain fields and a chemical shift caused by a self-interstitial neighboring a phosphorus atom. Two configurations of this complex differ only slightly in energy.