The effect of hot electron stress on the DC and microwave characteristics of AlGaAs/InGaAs/GaAs PHEMTs

摘要

This work reports on hot electron reliability of 0.25 /spl mu/m Al/sub 0.25-/ Ga/sub 0.75/As/In/sub 0.2/Ga/sub 0.8/As/GaAs PHEMTs from the viewpoint of both DC and RF characteristics. The changes of DC and RF behavior after high drain bias stressing are shown to be strongly correlated. Both can be attributed to a decrease of the threshold voltage, yielding different effects on gain depending on the bias point and circuitry chosen for device operation: a fixed current bias scheme is shown to minimize the changes induced by the stress.