DESIGN OF HIGH-POWER, HIGH-EFFICIENCY 60-GHZ MMICS USING AN IMPROVED NONLINEAR PHEMT MODEL

This work describes the design and nonlinear modeling of two V-band mo nolithic microwave integrated circuit (MMIC) power amplifiers using a nonlinear high electron mobility transistor (HEMT) model developed spe cifically for very short gate length pseudomorphic HEMT's (PHEMT's), B oth circuits advance the state-of-the-art of V-band power MMIC perform ance, The first, a single-ended design, produced 293 mW of output powe r with a record 26% power-added efficiency (PAE) and 9.9 dB of power g ain at 62.5 GHz when measured on-wafer, The second MMIC, a balanced de sign with on-chip input and output Lange couplers for power combining, generated a record 564 mW of output power (27.5 dBm) with 21% PAE and 9.8 dB power gain, The MMIC's are passivated, thinned to 2 mils, and down-biased to 4.5 V for high reliability space applications, These ex cellent first-pass MMIC results are attributed to the use of an optimi zed 0.1-mu m PHEMT cell structure and a design based on millimeter-wav e on-wafer device characterization, together with a new and very accur ate large signal analytical FET model developed for 0.1-mu m PHEMT's.