Offer | Applications | Resonators
Resonators
The MultiMEMS MPW process allows the manufacturing of resonant structures that can be incorporated in various sensing devices or energy harvesters.
The resonant structures can be either silicon structures, such as beams and membranes, or cavities designed as acoustic resonators.
The resonant structures can be directly used as sensing elements if their resonance frequencies depend on specific external parameters. In such cases, the structures must be first excited[1], then maintained at resonance.
In other applications, such as energy harvesting, the structures are set in resonance by external mechanical vibrations.
Silicon Resonating Structures
The devices pictured below, featuring resonating cantilevers, have been developed by SINTEF for energy harvesting. To convert the mechanical oscillations of the structures into electrical signals, the devices required piezoelectric layers offered as 
Add-ons by microBUILDER consortium.
 Energy harvesters with resonating cantilevers. © 2007 SINTEF. |
The device pictured below, featuring a resonating cantilever, has been designed by MICAS for flow detection.
 Flow detector with resonant cantilever. © 2004 KU Leuven. |
The device pictured below, featuring a set of resonating beams, has been designed by CNM for strain measurement purposes.
 Strain sensor with resonating beams. © 2004 CNM. |
Acoustic Resonators
The devices pictured below, featuring resonating cavities, have been designed by MICAS for flow rate measurements.
 Flow sensing devices with resonant cavities. © 2004 KU Leuven. |
Other Examples of Resonant Structures
The 
MASCOT gas sensor features an acoustic Helmholtz resonator formed by two glass cavities and a narrow channel.
The SA30 crash sensor features an acceleration-sensitive resonant structure that can be thermally excited.
Remarks
1. Without employing external components, only the thermal excitation by resistive heating is possible in the MultiMEMS MPW process.