Microscopic identification and electronic structure of a di-hydrogen–vacancy complex in silicon by optical detection of magnetic resonance

We present a microscopic identification of a hydrogen-related-complex defect in electron-irradiated, hydrogenated, boron-doped, single-crystalline silicon, by optical detection of magnetic resonance. The symmetry of this defect has been deduced as C₂ᵥ, and from the observed hyperfine interactions the defect is identified as a di-hydrogen--vacancy complex, where the H atoms passivate two of the four dangling bonds in a monovacancy. A spin-triplet is the lowest electronic excited state of the defect, which exhibits a strong recombination channel for the free-carriers.