Development of Bulk-Titanium-Based MEMS RF Switch for Harsh Environment Applications

Abstract

This paper presents a preliminary investigation into the viability of a new route for the fabrication of titanium-based MEMS RF switches for harsh environment applications. Titanium’s intrinsic toughness and corrosion resistance suggest that it would be highly suitable for such applications and recently developed titanium micromachining technologies now make exploration of this potential possible. Two design generations of electrostatically-actuated Bulk-Titanium MEMS (BT-MEMS) switches were fabricated and tested. First generation devices demonstrated that actuation at moderate voltages could be achieved (~60V), however stiction upon contact was common. This stiction was mitigated in the second generation devices through design modification and development of a new Titanium on Insulator (TOI) based process. These devices displayed stiction-free actuation and relatively low contact resistance (~1Ω). These preliminary results therefore demonstrate the potential of this process technology for fabrication of titanium-based RF switches for harsh environment applications.