Ultra-sensitive graphene membranes for microphone applications
Gabriele Baglioni (TU Delft - QN/van der Zant Lab, Kavli institute of nanoscience Delft)
Roberto Pezone (TU Delft - Electronic Components, Technology and Materials)
S Vollebregt (TU Delft - Electronic Components, Technology and Materials)
Katarina Zobenica (University of Belgrade)
Marko Spasenović (University of Belgrade)
Dejan Todorović (Dirigent Acoustics Ltd)
H. Liu (TU Delft - Dynamics of Micro and Nano Systems)
Gerard Verbiest (TU Delft - Dynamics of Micro and Nano Systems)
H. S J van der Zant (TU Delft - QN/van der Zant Lab, Kavli institute of nanoscience Delft)
Peter Steeneken (Kavli institute of nanoscience Delft, TU Delft - QN/Steeneken Lab, TU Delft - Dynamics of Micro and Nano Systems)
More Info
expand_more
Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.
Abstract
Microphones exploit the motion of suspended membranes to detect sound waves. Since the microphone performance can be improved by reducing the thickness and mass of its sensing membrane, graphene-based microphones are expected to outperform state-of-the-art microelectromechanical (MEMS) microphones and allow further miniaturization of the device. Here, we present a laser vibrometry study of the acoustic response of suspended multilayer graphene membranes for microphone applications. We address performance parameters relevant for acoustic sensing, including mechanical sensitivity, limit of detection and nonlinear distortion, and discuss the trade-offs and limitations in the design of graphene microphones. We demonstrate superior mechanical sensitivities of the graphene membranes, reaching more than 2 orders of magnitude higher compliances than commercial MEMS devices, and report a limit of detection as low as 15 dBSPL, which is 10-15 dB lower than that featured by current MEMS microphones.