Robust silicon carbide (SiC) nanoelectromechanical switches with long cycles in ambient and high temperature conditions

Abstract

We report experimental demonstration of nanoscale electromechanical contact-mode switches with clearly high comparative performance, enabled by polycrystalline silicon carbide (poly-SiC) nanomechanical cantilevers, in a three-terminal, gate-controlled, lateral configuration. We have recorded the complete time evolution of the measured switching events in ambient air, by switching devices on and off for ≥10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sup> -10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sup> cycles without failure (i.e., devices still alive; special accelerated tests are needed to properly `exhaust' the device and approach its intrinsic lifetime). These SiC nanoelectromechanical systems (NEMS) based switches have all dimensions but length in nanometer scale, and demonstrate on/off ratios of ~10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sup> or higher, with repeatable performance over days in air. We have also demonstrated SiC NEMS switches operating at high temperature (T≈500°C) in air. With a typical motional volume of only ~1μm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> and long `hot' switching cycles in air, these SiC devices exhibit strong potential toward realizing robust NEMS switches and logic circuits.