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Recent Patents on Engineering


ISSN (Print): 1872-2121
ISSN (Online): 2212-4047

Review Article

Design and Analysis of Capacitive Micromachined Ultrasonic Transducer

Author(s): Rashmi Sharma*, Rekha Agarwal, Ashwani Kumar Dubey and Anil Arora

Volume 13, Issue 2, 2019

Page: [108 - 116] Pages: 9

DOI: 10.2174/1872212112666180214141506

Price: $65


Background: Ultrasound refers to the acoustic energy above the human hearing range (20 Hz to 20 kHz) and finds applications in quality control of food technology, medical imaging, nondestructive testing, distance measuring etc. Ultrasonic transducers are designed to work both as a transmitter to generate ultrasound and as a receiver according to recent patents. Piezoelectric transducers have long dominated the society for generating ultrasound but recent developments in the Micromachining techniques have led to Capacitive Micromachined Ultrasonic Transducer (CMUT).

Objective: To simulate a Micromechanical systems (MEMS) based CMUT working as a transmitter with the existing design and provide comparison within the possible architectural geometries.

Methods: FEM simulation software COMSOL is used to simulate the 3D model of the transducer radiating in the air. The classical thin-plate theory is employed to solve for CMUT with a circular shape which is sufficient when the ratio of the diameter to thickness of the plate is very large, an aspect common in CMUTs. The Galerkin-weighted residual technique is used to get a solution for thin plate equation with the presumption that the deflections are small in comparison to the thickness of the plate.

Results: The resonant frequency of CMUT with different geometries have been calculated. The deflection of membrane with applied DC bias is shown along with collapse voltage calculation. The generated ultrasound is shown with the AC bias superimposed on the DC bias. The capacitance change with the increasing DC voltage is discussed. The deflection of membrane is maximum as the resonance frequency is proved.

Conclusion: The review of Capacitive Micromachined Ultrasonic Transducer architectures with different shapes is highlighted. The working behavior of CMUT with suitable dimension is simulated in 3D providing researcher data to wisely choose the CMUT prior to the fabrication. The CMUT is prioritized on various characteristics like wafer area utilization, deflection percentage within the cavity and durability of the transducer.

Keywords: CMUT architectures, diaphragm geometries, analytical view, electrostatics, acoustic pressure, transducer.

Graphical Abstract
M.F.l. Cour, T.L. Christiansen, C. Dahl-Petersen, K. Reck, O. Hansen, J.A. Jensen, and E.V. Thomsen, "Modeling and measurements of CMUTs with square anisotropic plates", In IEEE International Ultrasonics Symposium (IUS).Prague, Czech Republic 2013, pp. 2187-2190.
J. Song, C. Xue, C. He, R. Zhang, L. Mu, J. Cui, J. Miao, Y. Liu, and W. Zhang, "Capacitive micromachined ultrasonic transducers (CMUTs) for underwater imaging applications", Sensors , vol. 15, pp. 23205-23217, 2015.
O. Wygant, M. Kupnik, and B.T.K. Yakub, "Analytically calculating membrane displacement and the equivalent circuit model of a circular CMUT cell", In: IEEE Ultrasonics Symposium.Beijing, China, , 2008, pp. 2111–2114
A.L.P.C. Eccardt, "Linear and nonlinear equivalent circuit modeling of CMUTs", IEEE Trans. Ultrason. Ferroelectr. Freq. Control, vol. 52, pp. 2163-2172, 2005.
"Ladabaum, “Surface Micro Machined Capacitive Ultrasonic Transducers", IEEE Trans. Ultrason. Ferr., vol. 45, pp. 678-690, 1998.
V.W. Manthey, "Ultrasonic transducers and transducer arrays for application in air", Meas. Sci. Technol., vol. 3, pp. 249-261, 1992.
O. Oralkan, "Capacitive micromachined ultrasonic transducers: next-generation arrays for acoustic imaging", IEEE Trans. Ultrason. Ferr., vol. UFFC-42, pp. 52-58, 1986.
F. Degertekin, J. McLean, and J. Knight, CMUT devices and fabrication methods. U.S. Patent 20050177045A1, 2005
Z. Li, L. Zhao, Z. Jiang, Z. Ye, L. Dai, and Y. Zhao, "Mechanical behaviour analysis on Electrostatically actuated rectangular micro plate", J. Micromech. Microeng., vol. 25, p. 035007, 2015.
S.T. Hansen, B.J. Mossawir, A.S. Ergun, F.L. Degertekin, and B.T. Khuri-Yakub, "Air-Coupled non-destructive evaluation using micromachined ultrasonic transducers", Proc. IEEE Ultrason. Symp., vol. 2, pp. 1037-1040, 1999.
R.G. Nabian, M. Haddad-derafshi, and A. Tahmasebi, "Mechanical behavior of circular microplate subjected to uniform hydrostatic and non-uniform electrostatic pressure", Microsyst. Technol., vol. 14, pp. 235-240, 2008.
M. Rahman, and S. Chowdhury, "A new deflection shape function for square membrane CMUT design", In Proceedings of IEEE International Symposium on Circuits and Systems, 2010pp. 2019-2022 Paris, France,
P. Pursula, I. Marttila, K. Nummila, and H. Seppä, "High frequency and ultrahigh frequency radio frequency identification passive sensor transponders for humidity and temperature measurement within building structure", IEEE Trans. Instrum. Meas., vol. 62, pp. 2559-2566, 2013.
F.Y. Yamaner, S. Olcum, A. Bozkurt, and H. Köymen, "Optimizing CMUT geometry for high power", IN IEEE International Ultrasonics Symposium San Diego, CA, USA 2010, pp. 2247-2250.
M. Clerici, L. Caspani, E. Rubino, and M. Peccianti, "Counter-propagating difference-frequency generation in diamond with terahertz fields", In Conference on and International Quantum Electronics Conference Lasers and Electro-Optics Europe (CLEO EUROPE/IQEC) Munich, Germany , 2013, pp. 12-16.
S. Chouvardas, K. Slavakis, Y. Kopsinis, and S. Theodoridis, "A sparsity promoting adaptive algorithm for distributed learning", IEEE Trans. Signal Process., vol. 60, pp. 5412-5425, 2012.
O. Guldiken, J. Zahorian, F.Y. Yamaner, and F.L. Degertekin, "Dual-electrode CMUT with nonuniform membranes for high electromechanical coupling coefficient and high bandwidth operation", IEEE Trans. Ultrason. Ferr., vol. 56, pp. 1270-1276, 2009.
C. Tekes, J. Zahorian, G. Gurun, and S. Satir, "Volumetric imaging using single chip integrated CMUT-on-CMOS IVUS array", Conf. Proc. IEEE Eng. Med. Biol. Soc., vol. 2012, pp. 3195-3198, 2012.
P. D. Corl, Circuit architectures and electrical interfaces for rotational intravascular ultrasound (ivus) devices. EP Patent 2846699A4, 2016.
D. Barauskas, G. Vanagas, D. Virzonis, and A. Makaraviciute, "Capacitive micromachined ultrasound transducers (CMUT) for resonant gravimetric immune sensing", IEEE International Ultrasonics Symposium, 2014pp. 2588-2590 Chicago, IL, USA,
X. Zhuang, Capacitive micromachined ultrasonic transducers with through-wafer interconnects. ", PhD Thesis, Stanford University, Stanford, CA, USA,2008
M.M. Rahman, and S. Chowdhury, "Square diaphragm CMUT Capacitance calculation using a new deflection shape function", J. Sens., vol. 2011, pp. 1-12, 2011.
B. Oralkan, "Capacitive micromachined ultrasonic transducers: Next-generation arrays for acoustic imaging?", IEEE Trans. Ultrason. Ferr., vol. 49, pp. 1596-1610, 2002.
S. Timoshenko, and S. Woinowsky-Krieger, Theory of plates and shells., 2nd ed Mc Graw Hills: USA, 1987.
H. Wang, C. Xue, C. He, and X. Wang, "Design and performance analysis of capacitive micromachined ultrasonic transducer linear array", Micromachines (Basel), vol. 5, pp. 420-431, 2014.
I. Morkvenaite-Vilkonciene, D. Virzonis, G. Vanagas, and V. Krikscikas, "Operating point of capacitive micromachined ultrasonic transducers with sub-structural elements", Elektron. Elektrotech., vol. 18, pp. 43-46, 2012.
P.F. Chong, X. Shi, and C.H. Cheng, "A capacitive micromachined ultrasonic transducer (CMUT) array with nickel membranes in a convex shape", In 9th IEEE Intl. Conf. Nano/Micro Engineered and Molecular Systems (NEMS), 2014pp. 596-599 13-16. , Waikiki Beach, HI, USA, ,
Z. Li, L. Zhao, Z. Jiang, Z. Ye, and Y. Zhao, "An improved method for the mechanical behavior analysis of electrostatically actuated microplates under uniform hydrostatic pressure", J. Microelectromech. Syst., vol. 24, pp. 474-485, 2015.
W. You, E. Cretu, and R. Rohling, "Analytical modeling of cmuts in coupled electro-mechano- acoustic domains using plate vibration theory", IEEE Sens. J., vol. 11, pp. 2159-2168, 2011.
F.Y. Yamaner, S. Olcum, A. Bozkurt, and H. Köymen, "Optimizing CMUT geometry for high power", In IEEE International Ultrasonics Symposium San Diego, CA, USA 2010, pp. 2247-2250.
A. Lohfink, and P.C. Eccardt, "Linear and nonlinear equivalent circuit modeling of CMUTs", IEEE Trans. Ultrason. Ferr., vol. 52, pp. 2163-2172, 2005.
J.M. López, and C.S. López, "Electromechanical performance comparison for different CMUT element geometries", Intl. Conf. Synthesis, Modeling, Analysis and Simulation Methods and Applications to Circuit Design (SMACD), 2012pp. 109-112 Seville, Spain,
S. Olcum, M.N. Senlik, and A. Atalar, "Optimization of the gain band width product of capacitive micromachined ultrasonic transducers", IEEE T. Ultrason. Ferr., vol. 52, pp. 2211-2219, 2005.
B. Ahmad, and R. Pratap, "Elasto-electrostatic analysis of circular microplates used in capacitive micromachined ultrasonic transducers", IEEE Sens. J., vol. 10, pp. 1767-1773, 2010.
E. Ventsel, and T. Krauthammer, Thin plates and shells., 1st ed Marcel Deker: New York, 2001.
T. Zure, J. Hernandez, and S. Chowdhury, "Dynamic analysis of an SOI based CMUT", In IEEE International Conference on Industrial Technology (ICIT).Athens, Greece, 2012, pp. 539-544.
C. Meynier, Y. Yanamer, M. Canney, and A. Nguyen-Dinh, "Performance assessment Of CMUTs in dual modality imaging/HIFU applications", In IEEE International Ultrasonics Symposium Dresden, Germany 2012, pp. 81-84.
S. Satir, T. Xu, and F.L. Degertekin, "Model based drive signal optimization of CMUTs in non-collapse operation and its experimental validation", In IEEE International Ultrasonics Symposium (IUS) Prague, Czech Republic 2013, pp. 295-298.,
N. Sénégond, A. Boulmé, C. Plag, and F. Teston, "Fast time-domain modeling of fluid-coupled CMUT cells: from the single cell to the 1-D linear array element", IEEE Trans. Ultrason. Ferr., vol. 60, pp. 1505-1518, 2013.
S. Satir, and F.L. Degertekin, "A computationally efficient nonlinear System model for CMUT arrays", IEEE International Ultrasonics Symposium Chicago, IL, USA , 2014, pp. 313-316.

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