Spectrum of hot-electron luminescence from high electron mobility transistors.

GaAs and InGaAs high electron mobility transistors (HEMTs) have been found to emit visible and infrared radiation when subject to high drain/source biases. This luminescence has been studied and analyzed spectrally; there appear to be components due to electron indirect intraband transitions, in addition to recombination in various layers of the HEMT. The distinct recombination peaks indicate that carriers are distributed vertically in the transistor; the relative strength of luminescence at particular energies may provide indications of the relative carrier densities. This electroluminescence spectrum strongly suggests that real-space transfer may be significant in HEMTs.