Even-Parity Excited States Of The Acceptor Boron In Silicon Revisited

While the odd-parity electronic excited states of the prototypical acceptor boron in silicon have received detailed experimental and theoretical study, the properties of the even-parity excited states are less well known. Indeed, a recent study has strongly questioned the existing assignment of the first even-parity excited state above the 1 Gamma(+)(8) ground state, and further questioned whether the assigned state is even in the silicon band gap. Here we report the results of electronic Raman scattering spectroscopy, acceptor bound exciton two-hole spectroscopy, and thermally induced infrared absorption spectroscopy, all of which support the original assignment of the lowest-lying even-parity excited state of boron in silicon to the 1 Gamma(+)(7) state associated with the split-off valence band.