ABSTRACT
This chapter introduces a Nanoelectromechanical (NEM) switch design suitable for digital computing and then discusses body biasing schemes for minimizing the operating voltage and switching energy. NEM switches are promising alternatives to complementary metal-oxide semiconductor (CMOS) transistors for ultra-low-power digital integrated circuit applications due to their virtually zero off-state leakage current and abrupt switching characteristics. A NEM switch comprises mechanical-actuation and current-conduction portions. Piezoelectric NEM switches rely on the latter transduction mechanism to open or close air gaps between electrical contacts. An electrostatic NEM switch utilizes the electrostatic force between charges of opposite polarity on two opposing electrodes that form a capacitor; usually one electrode is fixed and the other is movable. NEM switches can be monolithically integrated over CMOS circuitry in a cost-effective manner by leveraging the back-end-of-line process. Monolithic integration of NEM switches with CMOS transistors can leverage the advantages of both technologies.
