3D FBAR Surface Deformation at Resonance

Model Description

Film bulk acoustic resonators (FBARs) can often exhibit spurious modes across the pass band which is one of design challenges an RF engineer faces. OnScale gives engineers the ability to quickly prototype a design to understand how effective it is removing these modes.

The 3D FBAR model provides a simple starting structure consisting of a piezoelectric active layer (Aluminum Nitride) with Molybdenum electrodes on a silicon substrate.

Model Schematic

Parametric Variables
The base model allows the following design variables to be adjusted. By default electrode thickness and electrode aspect ratio are set as design variables to be swept (indicated by *).

Parametric Variable Description Default Value
 aln_thk* Thickness of AlN piezoelectric layer  800 nm
 targ_wid* Width of top electrode  30 um
 sub_out Distance from end of cavity to end of AlN  5 µm
 cav_out Distance from end of electrode to end of cavity  5 µm
 cav_thk Thickness of cavity  1 µm
 elec_bot Bottom electrode thickness  400 nm
 elec_tot Top electrode thickness  400 nm

A wide range of outputs can be generated, including:

  • Electrical Impedance
  • Quality Factor
  • Mode Shapes (Harmonic Analysis)

Post Processor Outputs

Runtime Statistics

 Model Size  184093 elements
Solve Time  343 secs (16 CPUS)
Core Hours  1.54
Memory Usage  269 MB
Recommended CPU Configuration  16 CPU


The following input files are required to run this model:

Design Studies

Coming Soon…

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