High Performance Seesaw Torsional CMOS-MEMS Relay Using Tungsten VIA Layer

In this paper, a seesaw torsional relay monolithically integrated in a standard 0.35 μm complementary metal oxide semiconductor (CMOS) technology is presented. The seesaw relay is fabricated using the Back-End-Of-Line (BEOL) layers available, specifically using the tungsten VIA3 layer of a 0.35 μm CMOS technology. Three different contact materials are studied to discriminate which is the most adequate as a mechanical relay. The robustness of the relay is proved, and its main characteristics as a relay for the three different contact interfaces are provided. The seesaw relay is capable of a double hysteretic switching cycle, providing compactness for mechanical logic processing. The low contact resistance achieved with the TiN/W mechanical contact with high cycling life time is competitive in comparison with the state-of-the art.