Novel fabrication of integrated submillimeter circuits

Backside wafer processing has been developed for discrete beamlead diodes and beamlead MMICs. Backside etching allows arbitrary substrate geometry. The beamleads are used to make electrical connections to a waveguide block and/or serve as substrateless transmission lines. The fabrication of an 82.5 to 330 GHz MMIC balanced frequency quadrupler is presented.