Temperature dependence of optical properties of the deep sulfur center in silicon

Abstract

Spectral distributions of the hole photoionization cross section of the deep sulfur center in silicon have been measured at 10 different temperatures within the range 75 K≤T≤297 K applying the steady-state photocurrent technique. Zero-phonon hole binding energies of the deep donor level have been determined at these temperatures by using a detailed numerical fitting procedure. The temperature dependence of the hole binding energy is well described by a novel analytical formula with a zero-temperature binding energy of 557 meV. Further analysis of our data resulted in a lattice adjustment energy (Franck–Condon shift) of 51 meV and an associated average phonon energy of 33 meV.