Band-structure effects in the hot-carrier emission spectrum of GaAs FET devices
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 Tel determined by the exponential fit to the experiment.