Tuning dissipation dilution in 2D material resonators by MEMS-induced tension

TL;DR

This paper demonstrates a MEMS-based method to enhance the Q-factor of 2D material resonators by applying in-plane tension, achieving a 91% increase and enabling better sensor performance and loss mechanism studies.

Contribution

It introduces a dry-transfer fabrication technique with a platinum clamp for MEMS-actuated tensioning, significantly improving the Q-factor of 2D resonators without wet processing.

Findings

Q-factor increased by 91% through dissipation dilution

Dry-transfer fabrication avoids wet processing steps

Method enables studies of intrinsic loss mechanisms in 2D materials

Abstract

Resonators based on two-dimensional (2D) materials have exceptional properties for application as nanomechanical sensors, which allows them to operate at high frequencies with high sensitivity. However, their performance as nanomechanical sensors is currently limited by their low quality ($Q$)-factor. Here, we make use of micro-electromechanical systems (MEMS) to apply pure in-plane mechanical strain, enhancing both their resonance frequency and Q-factor. In contrast to earlier work, the 2D material resonators are fabricated on the MEMS actuators without any wet processing steps, using a dry-transfer method. A platinum clamp, that is deposited by electron beam-induced deposition, is shown to be effective in fixing the 2D membrane to the MEMS and preventing slippage. By in-plane straining the membranes in a purely mechanical fashion, we increase the tensile energy, thereby diluting dissipation. This way, we show how dissipation dilution can increase the $Q$-factor of 2D material resonators by 91\%. The presented MEMS actuated dissipation dilution method does not only pave the way towards higher $Q$-factors in resonators based on 2D materials, but also provides a route toward studies of the intrinsic loss mechanisms of 2D materials in the monolayer limit.