A monolithic GaAs X-band power amplifier

The work reported in this paper concerns the design, technology, and microwave performance of a single stage, monolithic X-band FET power amplifier with on-chip (printed) matching circuits. The use of "via" holes for low-inductance grounding and air-bridge source overlay connections for paralleling the individual FET cells is illustrated. The evolution of the chip design from a single FET circuit, exhibiting 500 mW output at 9.5 GHz, to a two-FET combiner, and finally to a four-FET combiner with over 2 watts output, is described.