17O hyperfine structure of the neutral (S = 1) vacancy-oxygen center in ion-implanted silicon

The intensity of the ¹⁷O hyperfine spectrum associated with the ²⁸Si-¹⁷O-²⁸Si isotopic configuration of the vacancy-oxygen (Si-S1) center was enhanced by ion implantation of ¹⁷O into silicon. The Si-S1 ¹⁷O hyperfine spectrum was measured by electron paramagnetic resonance. An analysis of the Si-S1 ¹⁷O hyperfine spectrum indicates that the numerical values for the elements in the ¹⁷O hyperfine coupling tensor A are Aₓₓ=-11.5₁×10⁻⁴ cm⁻¹, $A_{yy}=-{12.9}_0\times {10}^{-4}$ cm⁻¹, and $A_{zz}=-{13.3}_9\times {10}^{-4}$ cm⁻¹. The ¹⁷O hyperfine coupling tensor was analyzed in terms of the admixture of oxygen-valence orbitals into the one-electron paramagnetic molecular orbitals χ₁(Γ₁) and χ₄(Γ₄). In particular, only 4.1% of 〈χ₁(Γ₁)|χ₁(Γ₁)〉 and 1.8% of 〈χ₄(Γ₄)|χ₄(Γ₄)〉 are localized on the oxygen atom in this defect.