Strain-Modulated Equivalent Circuit Model and Dissipation Model for 2D MoS2 Nems Resonators

Abstract

Nanoelectromechanical systems (NEMS) resonators based on two-dimensional (2D) semiconductors such as molybdenum disulfide (MoS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) are highly promising for resonant sensors that can be homogeneously integrated with 2D logic circuits. However, the accurate modeling of the equivalent circuit and quality factor in these NEMS devices are largely unexplored. Here, we present a strain-modulated equivalent circuit and dissipation model focusing on NEMS resonators based on a 2D semiconductor: MoS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> . Especially, we find that when these suspended MoS <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> devices are in motion, the AC strain can induce changes in conductance, resulting in significant modifications in the output signal, which is unique to 2D semiconductors. The DC strain also modulates the quality factor because strain-induced potential energy is a crucial factor for the performance of a stretched membrane, which is verified against experimental results. The equivalent circuit and dissipation analysis build the solid platform for interfacing 2D NEMS resonators with external circuits and optimizing the quality factor. This study lay the foundation for using 2D resonators in high-sensitivity transducers and high-quality radio-frequency (RF) integrated circuits.