Impact of nonlinear drain resistance in bias-stressed InAlAs/InGaAs HEMTs

A study of the degradation of drain current under bias and temperature stre ss is presented for InP-based InAlAs/InGaAs HEMTs. Nonlinear drain resistan ce has been found to play an important role in the degradation. The decreas e in the drain current is caused by the rapid increase in the drain resista nce. The result suggests that the carrier density, which is originally suff icient to keep the resistance low and linear, decreases in the drain ohmic region.