A Two-stage, Two-way-combined, 220-GHz Power Amplifier With 17.1% PAE in a 250-nm InP HBT Process

A 220-GHz power amplifier (PA) in 250-nm Indium Phosphide (InP) is presented achieving a power added efficiency (PAE) of 17.1% at an associated output power of 43 mW. This design leverages common-base heterojunction bipolar transistors (HBTs) with cross-coupling capacitance for higher gain and improved stability. Two stages of gain are realized using pseudo-differential power combining of these cross-coupled cells through low-loss slot-line baluns and the overall PA occupies 230 x 350 um-sq which fits within a phased array pitch at G-band.