A GaAs Monolithic Phase Shifter for 30 GHz Application

The design and performance of a GaAs monolithic 180 degrees one-bit phase shifter test circuit for Ka-band operation is presented. Over the 27.5 to 30 GHz band the measured differential phase shift is within 10 degrees of the ideal characteristic and the insertion loss is between 4 and 6 dB. The switching FETs are fabricated by ion implantation into LEC material using a power FET implant schedule. I-V characteristics are also presented for a self-aligned gate FET whose channel resistance is reduced by more than a factor of two relative to the power FET. This latter fabrication technique holds promise in reducing phase shifter insertion loss for mm-wave applications.