Band-gap shifts in heavilyp-type doped semiconductors of the zinc-blende and diamond type

Abstract

We present derivations of the band-gap shifts in, and photoluminescence spectra from, heavily doped p-type semiconductors of zinc-blende and diamond type. The calculated final-state lifetimes are taken into account in the derivation of the luminescence peaks. They stem from the imaginary parts of the self-energy shifts due to electron-electron and electron–dopant-ion scattering. These are derived within the same formalism as the real parts causing the band shifts. Our results are compared in detail to those from photoluminescence experiments on p-type GaAs. The lifetime broadening is found to explain fully the low-energy tailing of the luminescence peaks. No assumption of band tailing is needed.