Design of C-band rectifier with Watt-class DC output using 0.18µm CMOS and GaN diode

This paper proposes a novel rectifier design method using a standard 0.18 μm CMOS MMIC and a GaN (Gallium Nitride) diode by hybrid semiconductor integrated circuit (HySIC) technology. The target RF input power is around 10 W at 5.8 GHz and output DC power is 2-3 W. To achieve such high input/output power with small CMOS chip, low impedance and wide thin-film micro-strip (TFMS) lines are used as impedance matching circuits. To protect capacitors from high voltage generation, series capacitor pairs are used as DC block and RF short circuits. A high linearity 3-stage nMOS SPST switch is also employed for the impedance match tuning. The GaN diode is modeled by measurement, and designed to be connected via eight bonding wires. The simulation results show that input return loss is lower than -14 dB, power efficiency is around 30% with 10 W RF input. The chip size is only 1.2 mm × 2.3 mm.