In-phase power-combined frequency triplers at 300 GHz

We report on the design, fabrication and characterization of a 300 GHz Schottky-diode frequency tripler made of two mirror-image integrated circuits that are power-combined in-phase in a single waveguide block using compact Y-junctions at the input and output waveguides. Each chip features six anodes on a 5 mu m thick GaAs membrane. The tripler has 5-15% conversion efficiency measured across the 265-330 GHz band when driven with 50-250 mW of input power at room temperature. At 318 GHz it delivers a peak power of 26 mW with 11 % conversion efficiency. The power-combined frequency multiplier is compared with a single-chip tripler designed for the same band using the same integrated circuit.