The design, fabrication,and experimental characteristics of a 100-GHz
monolithic cascode HEMT oscillator are presented. A cascode pair of In
AlAs/InGaAs HEMT's has been used as the active cell to enhance the neg
ative resistance so that more process tolerance can be achieved. The m
onolithic circuit oscillates around 100 GHz with an output power of 2
dBm at a drain bias voltage as small as 0.9 V. This is the first demon
stration of cascode HEMT oscillators at W-band.