Electronic structure and spectra of heavily doped n-type silicon

Theoretical calculations have so far focused on the band-gap reductions caused by heavy doping, but comparisons with experiment have not been informative because of large variations in values extracted from data on the basis of simple models. Calculations of photoluminescence spectra are reported which, for the first time, allow direct comparison with experimental data. It is found that intervalley scattering, previously assumed negligible, is essential in order to reproduce the major experimental features and trends.