PZE coupled Physics for Acoustic Resonators or Sensing & Actuation

Acoustic Resonators

The first successful RF filters were surface acoustic wave (SAW) filters, followed by bulk acoustic wave (BAW or FBAR) technology to address demand above 1 GHz where SAW device performance degrades1.  Most recently, bulk mode resonators that vibrate in plane to allow multi-frequency filters on one substrate have become increasingly popular. These in-plane bulk-mode resonators come by various names such as contour-mode resonators (CMR) and laterally-vibrating resonators (LVR).

CoventorWare offers unique capabilities that aid acoustic resonator designers:

  • Unprecedented speed for simulating the frequency response of 3D models that precisely capture the main resonance and spurs, using the FastPZE solver.
  • Automatic extraction of design metrics such as BVD parameters, electromechanical coupling, and series and parallel resonances.
  • Automated multi-port analysis and S-parameter export to Touchstone format.
  • Efficient meshing capabilities for non-Manhattan designs containing arbitrary polygons or curved edges. For thin-film acoustic structures, it is critical to avoid the extremely large number of mesh elements required by tetrahedral meshes.
  • Modelling of other aspects of resonator design such as thermal coefficient of frequency (TCF), thermo-elastic damping (TED), and anchor loss.
3D Laterally-vibrating resonator from Gong2 showing plane view and cross-section of modal amplitude at 0.48 GHz overlaid on admittance response

Image of 3D Laterally-vibrating resonator from Gong2 showing plane view and cross-section of modal amplitude at 0.48 GHz overlaid on admittance response. The response includes all spurious modes or spurs.

Energy Harvesters & PZE Actuators

CoventorWare can also be used to model other transducers that utilize PZE physics, for example Energy Harvesters or PZE actuators for driving Micromirrors. Here the device response to static and dynamic loads can be simulated to predict charge and voltage generated as well as displacement and stress. The latter may be important for example when the device is overloaded due an acceleration shock.

The animation shows a 3D contour plot of the simulated open-circuit potential and displacement of a PZE energy harvester under vibrational acceleration load3.

  1. Aigner, “SAW, BAW and the future of wireless”, EDN, May 2013, http://www.edn.com/design/wireless-networking/4413442/SAW–BAW-and-the-future-of-wireless
  2. Songbin Gong and Gianluca Piazza, “Figure-of-Merit Enhancement for Laterally Vibrating Lithium Niobate MEMS Resonators”, IEEE Transactions on Electron Devices, Vol. 60, No. 11, November 2013.
  3. Hohlfelda, S. Matovaa, R. van Schaijka, C. J. Welhamb, S. Rouvilloisb aHolst Centre / IMEC, High Tech Campus 31, 5656 AE Eindhoven, The Netherlands bCoventor, 3 Ave Du Quebec, Villebon Sur Yvette, France, Experimental validation of micromachined vibrational energy harvester module, Eurosensors 2009.