Silicon Luminescence Spectra Modelling and the Impact of Dopants

Abstract

This paper presents findings on applying physical models in the literature to describe silicon luminescence spectra at 80 – 300K. Incorporation of exciton recombination models are shown to disagree with the measured luminescence spectra, whereas a free electron-hole recombination model is shown to match well with the luminescence spectra. However, the lack of consideration for excitons is not justified, as Bludau et al. [J. Appl. Phys., vol. 45, p. 1846, 1974] reported that excitons are present even at room temperature. The second part of the paper demonstrates the impact of shallow dopants on the silicon luminescence spectra at 79K. The ratio of the dopant-related peak to the band-to-band peak intensities correlates with the dopant concentration, indicating that luminescence spectroscopy has the potential for quantifying dopant concentrations in silicon in this temperature range.