Abstract

The aim of this investigation is to study hot electron phenomena leading to impact ionization and light emission in commercial InGaAs-channel pseudomorphic HEMTs. Optical measurements have been performed at several temperatures by rneans of a single-photon counting technique in the range 1.1 eV - 3.0 eV, while biasing the devices in the impact ionization regime. The observed spectra show a sharp peak that denotes band-to-band recombinations of cold carriers and a high energy tail corresponding to hot electron transitions.