Band-structure effects in the hot-carrier emission spectrum of GaAs FET devices

Abstract

We have measured the hot-electron luminescence of GaAs HEMT devices over a broad spectral range in the infrared (0.4-1.4 eV). The emission intensity has spectral features suggesting that k-conserving, interconduction-band transitions dominate the emission process. The interpretation of emission spectra in terms of a hot-carrier distribution requires consideration of band-structure effects. In general this tends to reduce values of electron temperature T,, determined by the exponential fit to the experiment.

Experimental characterization of hot-electron-induced effects and light emission in heterostructure devices

“…Both the intensity of the emitted light and the equivalent electron temperature increase at increasing drain voltages. It should be stressed, however, that the emitted spectra most possibly result from the contribution of different emission contributions, so that the observed photon distribution cannot be directly related to the original electron energy distribution [4].…”