EPR of a trapped vacancy in boron-doped silicon

Abstract

An $S=\frac{1}{2}$ EPR spectrum, labeled Si-G10, is tentatively identified as a lattice vacancy trapped by substitutional boron in silicon. It is produced in boron-doped vacuum floating-zone silicon by 1.5-MeV-electron irradiation at 20.4 K followed by an anneal at ∼ 180 K, where the isolated vacancy disappears. From the symmetry of the spectrum and its motional degrees of freedom, as revealed in studies of linewidth versus temperature and defect alignment versus stress, it is deduced that the boron atom is a next-nearest neighbor to the vacancy. The defect is not stable at room temperature, recovering at ∼ 260 K.