"Plug-up"-a new concept for fabricating SOI MEMS devices

This paper reports a novel process sequence for making micromechanical devices on silicon on insulator (SOI) wafers. The merits of the new process are its improved immunity to stiction and elimination of conductor metal endurance problems during sacrificial etching with hydrofluoric acid (HF). With this new process one can fabricate vacuum cavities on blank SOI substrates. Further processing of these cavity wafers enables the realization of a wide variety of single crystal micromechanical devices.