In this paper we demonstrate the straight correlation between the inte
grated light emitted and the DC currents in GaAs-based pseudomorphic H
EMTs biased at high drain voltage, when, due to hot electrons, impact
ionization takes place. By means of electrical and optical measurement
s, we found three different recombination mechanisms, which originate
the light emission in three different energy ranges. (C) 1998 Elsevier
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