Graphene Squeeze-Film Pressure Sensors

TL;DR

This paper demonstrates a graphene-based squeeze-film pressure sensor that exhibits a high responsivity and significantly outperforms traditional MEMS sensors in sensitivity and size, leveraging the unique properties of graphene membranes.

Contribution

The study introduces a novel graphene membrane sensor for pressure detection, achieving higher responsivity and smaller size compared to existing MEMS-based sensors.

Findings

Frequency shift of 4 MHz between 8 and 1000 mbar

Responsivity of 9000 Hz/mbar, 45 times higher than state-of-the-art

Smaller membrane area by a factor of 25

Abstract

The operating principle of squeeze-film pressure sensors is based on the pressure dependence of a membrane's resonance frequency, caused by the compression of the surrounding gas which changes the resonator stiffness. To realize such sensors, not only strong and flexible membranes are required, but also minimization of the membrane's mass is essential to maximize responsivity. Here, we demonstrate the use of a few-layer graphene membrane as a squeeze-film pressure sensor. A clear pressure dependence of the membrane's resonant frequency is observed, with a frequency shift of 4 MHz between 8 and 1000 mbar. The sensor shows a reproducible response and no hysteresis. The measured responsivity of the device is 9000 Hz/mbar, which is a factor 45 higher than state-of-the-art MEMS-based squeeze-film pressure sensors while using a 25 times smaller membrane area.