Optimized X and Ku band GaAs MMIC varactor tuned FET oscillators

The modeling techniques used to understand and predict the phenomena of frequency hops and holes in X-band and Ku band monolithic microwave integrated circuit (MMIC) voltage-controlled oscillators (VCOs) are described. The use of nonlinear circuit analysis has led to circuit improvements, including a novel lateral varactor structure compatible with FET devices and uniform ion-implanted material, realizing better Q. Devices were fabricated and tested, confirming the validity of the modeling and design approaches. Monolithic X-band and Ku-band VCOs realized continuous tuning over 5.9-12.6 GHz and 10.6-20.4 GHz, respectively; continuous tuning was retained over the temperature range -55 to +90 degrees C.<>