Microsystem Technologies

, Volume 23, Issue 6, pp 2163–2173 | Cite as

An improved analytical and finite element method model of nanoelectromechanical system based micromachined ultrasonic transducers

  • Reshmi Maity
  • Niladri Pratap Maity
  • R. K. Thapa
  • Srimanta Baishya
Technical Paper
First Online:
Received:
Accepted:

Abstract

This paper accurately models the silicon nitride membrane displacement profile of nanoelectromechanical system (NEMS) capacitive micromachined ultrasonic transducer (CMUT). The general analytical model is proposed for the linear and non-linear region of operation with the choice of the appropriate spring constant value. Calculated results are validated with 2-D finite element method (FEM) solver PZFLEX. Full 3-D simulations are carried out to show that for a constant area the circular geometry gives maximum displacement followed by hexagonal and square membranes, respectively. Variation of the membrane displacement with its thicknesses, radii, the electrode separation and voltages are plotted. These demonstrate how a CMUT membrane’s displacement can be optimized with a change in structural geometries and biases which is a necessary condition for obtaining the required sensitivity. The model evaluates the collapse voltage very close to experimental and FEM results. The dependency of the resonances on the thickness of the membrane is evaluated. Though this phenomenon is not noticed in the available literature, the FEM results support it. The FEM strain profile also reveals that at the operating biases the structure is working well under its strain limit as predicted by the analytical model.

Keywords

Finite Element Method Lamb Wave Finite Element Method Model Finite Element Method Result Circular Membrane 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Notes

Acknowledgments

The authors acknowledge the VLSI Design and MEMS Laboratory of Department of Electronics and Communication Engineering at Mizoram University (A Central University), Aizawl, India for providing all necessary facilities to carry out the research.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Reshmi Maity
    • 1
    • 2
  • Niladri Pratap Maity
    • 1
    • 2
  • R. K. Thapa
    • 3
  • Srimanta Baishya
    • 2
  1. 1.Department of Electronics and Communication EngineeringMizoram University (A Central University)AizawlIndia
  2. 2.Department of Electronics and Communication EngineeringNational Institute of TechnologySilcharIndia
  3. 3.Department of PhysicsMizoram University (A Central University)AizawlIndia

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