A multimechanism model for photon generation by silicon junctions in avalanche breakdown

Light emission from three device types (1) commercial silicon JFET's, 2) bi polar transistors, and 3) a custom diode) with p-n junctions biased in cont rolled avalanche breakdown, has been measured over the photon energy range 1.4-3.4 eV, Previously published models are compared with these data to elu cidate the mechanisms responsible for avalanche light emission in silicon. A multimechanism model fitting measured spectra and spectra measured by oth er researchers is presented and justified. The success of the model indicat es that indirect recombination of electrons and holes is the dominant emiss ion mechanism below the light intensity peak (similar to 1.8-2.0 eV), that indirect intraband recombination dominates at intermediate energies up to s imilar to 2.3 eV, and that direct interband recombination between high-fiel d populations of carriers near k=0 dominates above similar to 2.3 eV, For j unctions with overlayer passivation, an interference model must be applied to model measured spectra,.