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Register a new userNanoelectromechanical Sensors based on Suspended 2D Materials
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The unique properties and atomic thickness of two-dimensional (2D) materials enable smaller and better nanoelectromechanical sensors with novel functionalities. During the last decade, many studies have successfully shown the feasibility of using suspended membranes of 2D materials in pressure sensors, microphones, accelerometers, and mass and gas sensors. In this review, we explain the different sensing concepts and give an overview of the relevant material properties, fabrication routes, and device operation principles. Finally, we discuss sensor readout and integration methods and provide comparisons against the state of the art to show both the challenges and promises of 2D material-based nanoelectromechanical sensing.
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We realize squeeze film pressure sensors using suspended, high mechanical quality silicon nitride membranes forming few-micron gap sandwiches. The effects of air pressure on the mechanical vibrations of the membranes are investigated in the range 10^-3-50 mbar and the intermembrane coupling induced by the gas is discussed in light of a squeeze film coupled-oscillator model. The high responsivity (several kHz/mbar) and the sub-pascal sensitivity of such simple pressure sensors are attractive for absolute and direct pressure measurements in rarefied air or high vacuum environments.
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