Fabrication and characterization of a highly doped poly-SiGe NEMS ohmic switches

M. Ramezani, S. Severi, B. Du Bois, T. Asafa, X. Rottenberg, V. Rochus, H.A. Tilmans, K. De Meyer, A. Witvrouw
IMEC, BE

Keywords: NEMS, Relay, Poly SiGe, Logic, CMOS compatible

Summary:

This work demonstrates the first prototype of an ohmic NEMS switch, which was fabricated based on an ultra-thin poly-SiGe technology at CMOS-compatible temperatures. This technology allows processing the NEMS switch directly on top of the CMOS backend of line. A NEMS switch can be used to add extra functionalities on top of CMOS circuits. Due to the extremely steep sub-threshold slope, it can be utilized as a power gating device. NEMS switches can be used to realize hybrid CMOS-MEMS memory cells for low power applications. Several research groups have investigated NEMS switches with different materials and integrations schemes. One of the main challenges is represented by the need of finding a technology that provides a reliable device down to sub micrometer size. The investigation presented in this paper on SiGe aims to tackle both of these challenges. Use a reliable SiGe mechanical material, directly on top of CMOS BEOL enabling the possibility to aggressively scale the device with direct access to CMOS interconnections.