Planar Schottky diodes for submillimeter wave applications

The main limitation of whisker-contacted diode technology is that no integration is possible. Therefore, the development of competitive planar Schottky barrier diodes has been put forward in the last decade. The quasi-vertical planar Schottky diode was proposed several years ago and the necessary technologies are developed for a reliable fabrication. We show the recent status of this type of planar Schottky diodes. At 200 GHz an output power of 5 mW (12.5% efficiency) has been achieved with a quasi-vertical planar varactor diode. Recent activities concentrate on anti-parallel Schottky mixer diodes and integration of diodes (0.8 /spl mu/m anode diameter) with several receiver components. These diodes offer characteristics comparable to substrateless diodes with the same diode parameters.