Fabrication of air-bridge Schottky diodes on germanium for high speed IR detectors

We report on the fabrication process of suspended anodes implemented in Schottky-diode devices on epitaxial Ge. An air-bridge technique based on reactive ion etching in SF"6 was developed in order to release the Schottky contact bridge, ensuring higher control respect to wet etching. Metal-semiconductor junctions in the sub-micron range with rectifying behaviour have been obtained. The present fabrication process can be extended as is to the use of silicon on insulator substrates.