Analysis on the Frequency Response of Circular Membrane and Square Membrane Micromachined Ultrasonic Transducer

H. Lalnunfeli; Reshmi Maity; Ramesh Chandra Tiwari; Niladri Pratap Maity

doi:10.29284/fetqde10

Authors

H. Lalnunfeli Department of Physics, Mizoram University (A Central University), Aizawl – 796004, INDIA
Reshmi Maity Department of Electronics and Communication Engineering, Mizoram University (A Central University), Aizawl - 796004, INDIA
Ramesh Chandra Tiwari Department of Physics, Mizoram University (A Central University), Aizawl – 796004, INDIA
Niladri Pratap Maity Department of Electronics and Communication Engineering, Mizoram University (A Central University), Aizawl - 796004, INDIA

DOI:

https://doi.org/10.29284/fetqde10

Keywords:

CMUT, MEMS, COMSOL, FEM, Computational models

Abstract

The capacitance micromachined ultrasonic transducers (CMUT’s) performance is significantly influenced by its shape. The objective of this research is to examine how different parameters of CMUT affects the resonant frequencies of two different shapes of CMUT. Our study investigates the differences between circular and square-shaped membranes, highlighting several key trends. The results demonstrate that thicker membranes and larger membrane radii lead to higher resonance frequencies. Additionally, a larger cavity radius results in lower resonant frequencies. The analysis also examines the effects of venting the membrane at the edge and center, revealing that edge venting decreases the device resonance frequency compared to a ventless membrane, providing valuable insights for CMUT design. The results of our study show that the circular-shaped membrane is more effective in achieving the desired CMUT frequency response, outperforming the square-shaped membrane in medical imaging system.

References

1. Haller M. I. and Khuri-Yakub B. T., “A surface micromachined electrostatic ultrasonic air transducer”, IEEE Transactions on Ultrasonic, Ferroelectrics, and Frequency control, 1996, 43(1), 1-6.

2. Hohlfeld K., Michaelis A., Gebhardt S., “Piezoelectric transducers on the basis of free-formed PZT components,” IEEE Proceedings of Joint International Symposium on Applications of Ferroelectric and Piezoresponse Force microscopy, DOI: 10.1109/ISAF.2013.6748675, 2013.

3. Y. Zhao et al., “Coupling Effects of Crosstalk and Parasitic Loss on Capacitive Micromachined Ultrasonic Transducers,” IEEE Sensors Journal, vol. 22, no. 4, pp. 3281–3297, Feb. 2022

4. C. Hmingthansanga, M. Reshmi, D. Shankar, N. P. Maity, Investigation and analysis of MEMS based capacitive sensor’s characteristics with the effect of electrode pattern, Microsystem Technologies, vol. 31, pp. 987-997, 2025

5. Khuri-Yakub B. T. and Oralkan O., “Capacitive Micromachined Ultrasonic Transducers for medical imaging and therapy”, Journal of Micromechanics and Microengineering; 21 (5): DOI: 10.1088/0960-1317/21/5/054004, 2011.

6. Haller M.I. and Khuri-Yakub B.T., “A surface micromachined electrostatic ultrasonic air transducer”. IEEE Ultrasonic Symposium, France, 1994, pp 1241-1244.

7. Huang Y., Ergun A.S., Haeggstrom E, Badi MH, Khuri-Yakub BT, “ Fabricating capacitive micromachined ultrasonic transducers with wafer-bonding technology”. Journal of Microelectromechanical Systems, 2003, Vol. 12, No. 2.

8. Maity R., Maity N.P., Thapa R.K., Baishya S., “Analysis of frequency response behaviour of capacitive micromachined ultrasonic transducers,” Journal of Computational and Theoretical Nanoscience, 2015, Vol. 12, 3492-3494.

9. C. Hmingthansanga, M. Reshmi, N. Bijit, K., D, Shakar, N. P. Maity, Performance analysis of FEM simulated different shaped membranes based capacitive MEMS sensor, Microsystem Technologies, vol. 31, pp 461-473, 2025

10. Huang X., Wang H., Yu L., “Investigation on design theory and performance analysis of vacuum capacitive micromachined ultrasonic transducer,” Micromachines 2021, 12(9), 1127.

11. Thacker M.B., Emadi A., Buchanan D.A., “Design, development, and characterization of a low frequency CMUT-based anemometer”, 2021, DOI 10.1109/ACCESS.2021.3112107.

12. H. Lalnunfeli, M, Reshmi, R. C. Tiwari, D. Shankar, N. P. Maity, Modeling and Investigation of Immersion based Capacitive Micromachined Ultrasonic Transducer, Microsystem Technologies, 30, 1315-1323, 2024

13. Ray A., Chandel V., Taiwade K., Bamne J., Bhargav A., Haque F.Z., “Design and analysis of CMUT device using COMSOL for radio frequency applications,” materials Today: Proceedings 2022, Vol. 65, 2602-2605.

14. Mills D. M., and Smith S. W., “Multi-layered PZT/polymer composites to increase signal-to-noise ratio and resolution for medical ultrasound transducers”, IEEE Transactions on Ultrasonic, Ferroelectrics, and Frequency control 46(4), 961-971, 1999.

15. Avik Ghosh Dastidar, Reshmi Maity, R. C. Tiwari, Shankar Dutta, N. P. Maity, An Analytical and FEM Simulation-based Study of the Dependence of Capacitance Profile on Structural Parameters of CMUT with and without Vent, Microsystem Technologies, 30, 1239-1248, 2024.

16. Avik Ghosh Dastidar, Moumita Pal, R. C. Tiwari, R. Maity, N. P. Maity, An efficient electrostatic actuation model for MEMS-based ultrasonic transducers with fringing effect, Microsystem Technologies, 29, 583-597, 2024

17. Jin X., Ladabaum I. and Khuri-Yakub B. T., The microfabrication of capacitive ultrasonic transducers”, IEEE/ ASME J. Microelectromechanical Systems, 1998, 7(3).

18. Avik Ghosh Dastidar, Reshmi Maity, R. C. Tiwari, D. Vidojevic, T. Kevkic, V. Nikolic, S. Das, and N. P. Maity, “Squeeze Film Effect in Surface Micromachined Nano Ultrasonic Sensor for Different Diaphragm Displacement Profiles’, Sensors, vol. 23, no. 10, p. 113712.

19. M. Pal, C. Lalengkima, R. Maity, S. Baishya, N. P. Maity, “Effects of fringing capacitances and electrode’s finiteness in improved SiC membrane based micromachined ultrasonic transducers,” Microsystem Technologies, vol. 27, pp. 3679-3691, 2021.

20. Bijit Kumar Nath, Reshmi Maity, Niladri Pratap Maity, “Enhanced capacitance modeling of a circular microelectromechanical system based transducer for sensitivity improvement”, Microsystem Technologies, vol. 31, No. 7, pp. 1863-1874

21. O. J. Adelegan, Z. Coutant, X. Wu, F. Yamaner, and O. Oralkan, “Design and Fabrication of Wideband Air-Coupled Capacitive Micromachined Ultrasonic Transducers With Varying Width Annular-Ring and Spiral Cell Structures,” IEEE Trans. on Ultrasonics Ferroelectrics and Frequency Control, vol. 68, no. 8, pp. 2749–2759, Apr. 2021.

22. H. Shahid, D. D. Berhanuddin, R. Latif, P. C. Ooi, and T. Batool, “Simulation-Based Approach to Detecting Pulmonary Embolism Using Capacitive Micromachined Ultrasonic Transducers,” 2024 IEEE International Conference on Semiconductor Electronics (ICSE), pp. 152–154, Aug. 2024.