Highly-sensitive wafer-scale transfer-free graphene MEMS condenser microphones
Abstract Since the performance of micro-electro-mechanical system (MEMS)-based microphones is approaching fundamental physical, design, and material limits, it has become challenging to improve them. Several works have demonstrated graphene’s suitability as a microphone diaphragm. The potential for...
Main Authors: | , , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Nature Publishing Group
2024-02-01
|
Series: | Microsystems & Nanoengineering |
Online Access: | https://doi.org/10.1038/s41378-024-00656-x |
_version_ | 1797274297145753600 |
---|---|
author | Roberto Pezone Sebastian Anzinger Gabriele Baglioni Hutomo Suryo Wasisto Pasqualina M. Sarro Peter G. Steeneken Sten Vollebregt |
author_facet | Roberto Pezone Sebastian Anzinger Gabriele Baglioni Hutomo Suryo Wasisto Pasqualina M. Sarro Peter G. Steeneken Sten Vollebregt |
author_sort | Roberto Pezone |
collection | DOAJ |
description | Abstract Since the performance of micro-electro-mechanical system (MEMS)-based microphones is approaching fundamental physical, design, and material limits, it has become challenging to improve them. Several works have demonstrated graphene’s suitability as a microphone diaphragm. The potential for achieving smaller, more sensitive, and scalable on-chip MEMS microphones is yet to be determined. To address large graphene sizes, graphene-polymer heterostructures have been proposed, but they compromise performance due to added polymer mass and stiffness. This work demonstrates the first wafer-scale integrated MEMS condenser microphones with diameters of 2R = 220–320 μm, thickness of 7 nm multi-layer graphene, that is suspended over a back-plate with a residual gap of 5 μm. The microphones are manufactured with MEMS compatible wafer-scale technologies without any transfer steps or polymer layers that are more prone to contaminate and wrinkle the graphene. Different designs, all electrically integrated are fabricated and characterized allowing us to study the effects of the introduction of a back-plate for capacitive read-out. The devices show high mechanical compliances C m = 0.081–1.07 μmPa−1 (10–100 × higher than the silicon reported in the state-of-the-art diaphragms) and pull-in voltages in the range of 2–9.5 V. In addition, to validate the proof of concept, we have electrically characterized the graphene microphone when subjected to sound actuation. An estimated sensitivity of S 1k H z = 24.3–321 mV Pa−1 for a V b i a s = 1.5 V was determined, which is 1.9–25.5 × higher than of state-of-the-art microphone devices while having a ~9 × smaller area. |
first_indexed | 2024-03-07T14:56:22Z |
format | Article |
id | doaj.art-53ae4195d6394368b9f0ce32d86a0e39 |
institution | Directory Open Access Journal |
issn | 2055-7434 |
language | English |
last_indexed | 2024-03-07T14:56:22Z |
publishDate | 2024-02-01 |
publisher | Nature Publishing Group |
record_format | Article |
series | Microsystems & Nanoengineering |
spelling | doaj.art-53ae4195d6394368b9f0ce32d86a0e392024-03-05T19:24:29ZengNature Publishing GroupMicrosystems & Nanoengineering2055-74342024-02-011011910.1038/s41378-024-00656-xHighly-sensitive wafer-scale transfer-free graphene MEMS condenser microphonesRoberto Pezone0Sebastian Anzinger1Gabriele Baglioni2Hutomo Suryo Wasisto3Pasqualina M. Sarro4Peter G. Steeneken5Sten Vollebregt6Laboratory of Electronic Components, Technology and Materials (ECTM), Department of Microelectronics, Delft University of TechnologyInfineon Technologies AGKavli Institue of Nanoscience, Department of Quantum Nanoscience, Delft University of TechnologyInfineon Technologies AGLaboratory of Electronic Components, Technology and Materials (ECTM), Department of Microelectronics, Delft University of TechnologyKavli Institue of Nanoscience, Department of Quantum Nanoscience, Delft University of TechnologyLaboratory of Electronic Components, Technology and Materials (ECTM), Department of Microelectronics, Delft University of TechnologyAbstract Since the performance of micro-electro-mechanical system (MEMS)-based microphones is approaching fundamental physical, design, and material limits, it has become challenging to improve them. Several works have demonstrated graphene’s suitability as a microphone diaphragm. The potential for achieving smaller, more sensitive, and scalable on-chip MEMS microphones is yet to be determined. To address large graphene sizes, graphene-polymer heterostructures have been proposed, but they compromise performance due to added polymer mass and stiffness. This work demonstrates the first wafer-scale integrated MEMS condenser microphones with diameters of 2R = 220–320 μm, thickness of 7 nm multi-layer graphene, that is suspended over a back-plate with a residual gap of 5 μm. The microphones are manufactured with MEMS compatible wafer-scale technologies without any transfer steps or polymer layers that are more prone to contaminate and wrinkle the graphene. Different designs, all electrically integrated are fabricated and characterized allowing us to study the effects of the introduction of a back-plate for capacitive read-out. The devices show high mechanical compliances C m = 0.081–1.07 μmPa−1 (10–100 × higher than the silicon reported in the state-of-the-art diaphragms) and pull-in voltages in the range of 2–9.5 V. In addition, to validate the proof of concept, we have electrically characterized the graphene microphone when subjected to sound actuation. An estimated sensitivity of S 1k H z = 24.3–321 mV Pa−1 for a V b i a s = 1.5 V was determined, which is 1.9–25.5 × higher than of state-of-the-art microphone devices while having a ~9 × smaller area.https://doi.org/10.1038/s41378-024-00656-x |
spellingShingle | Roberto Pezone Sebastian Anzinger Gabriele Baglioni Hutomo Suryo Wasisto Pasqualina M. Sarro Peter G. Steeneken Sten Vollebregt Highly-sensitive wafer-scale transfer-free graphene MEMS condenser microphones Microsystems & Nanoengineering |
title | Highly-sensitive wafer-scale transfer-free graphene MEMS condenser microphones |
title_full | Highly-sensitive wafer-scale transfer-free graphene MEMS condenser microphones |
title_fullStr | Highly-sensitive wafer-scale transfer-free graphene MEMS condenser microphones |
title_full_unstemmed | Highly-sensitive wafer-scale transfer-free graphene MEMS condenser microphones |
title_short | Highly-sensitive wafer-scale transfer-free graphene MEMS condenser microphones |
title_sort | highly sensitive wafer scale transfer free graphene mems condenser microphones |
url | https://doi.org/10.1038/s41378-024-00656-x |
work_keys_str_mv | AT robertopezone highlysensitivewaferscaletransferfreegraphenememscondensermicrophones AT sebastiananzinger highlysensitivewaferscaletransferfreegraphenememscondensermicrophones AT gabrielebaglioni highlysensitivewaferscaletransferfreegraphenememscondensermicrophones AT hutomosuryowasisto highlysensitivewaferscaletransferfreegraphenememscondensermicrophones AT pasqualinamsarro highlysensitivewaferscaletransferfreegraphenememscondensermicrophones AT petergsteeneken highlysensitivewaferscaletransferfreegraphenememscondensermicrophones AT stenvollebregt highlysensitivewaferscaletransferfreegraphenememscondensermicrophones |