Contrast-enhanced Ultrasound Imaging Using Capacitive Micromachined Ultrasonic Transducers

Abstract Capacitive micromachined ultrasonic transducers (CMUTs) have a nonlinear relationship between the applied voltage and the emitted signal, which is detrimental to conventional contrast-enhanced ultrasound (CEUS) techniques. Instead, a three-pulse amplitude modulation (AM) sequence has been proposed, which is not adversely affectedby the emitted harmonics. In this paper, this is shown theoretically, and the performance of the sequence is verified using a 4.8 MHz linear CMUT array, and a comparable lead zirconate titanate (PZT) array, across 6 V to 60 V applied AC voltage. CEUS images of the contrast agent SonoVue flowing through a 3D printed hydrogel phantom showed an average enhancement in contrast-to-tissue ratio (CTR) between B-mode and CEUS images of 49.9 dB and 37.4 dB for the PZT array and CMUT, respectively. Furthermore, hydrophone recordings of the emitted signals showed that the nonlinear emissions from the CMUT did not significantly degrade the cancellation in the compounded AM signal, leaving an average of 2% of the emitted power between 26 V and 60 V AC. Thus, it is demonstrated that CMUTs are capable of CEUS imaging independent of the applied excitation voltage when using a three-pulse AM sequence.

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Micromachined ultrasonic transducers based on lead zirconate titanate (PZT) films

Microsystem Technologies ◽

10.1007/s00542-012-1719-2 ◽

2012 ◽

Vol 19 (2) ◽

pp. 211-218 ◽

Cited By ~ 7

Author(s):

Junhong Li ◽

Chenghao Wang ◽

Jun Ma ◽

Mengwei Liu

Keyword(s):

Lead Zirconate Titanate ◽

Lead Zirconate ◽

Ultrasonic Transducers ◽

Zirconate Titanate ◽

Pzt Films

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Lithium tantalate/lead zirconate titanate composite ultrasonic transducers

Applied Physics Letters ◽

10.1063/1.123895 ◽

1999 ◽

Vol 74 (17) ◽

pp. 2552-2554 ◽

Cited By ~ 7

Author(s):

Y. Chen ◽

M. Sayer ◽

L. Zou ◽

C.-K. Jen

Keyword(s):

Lead Zirconate Titanate ◽

Lithium Tantalate ◽

Lead Zirconate ◽

Ultrasonic Transducers ◽

Zirconate Titanate

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Acoustic Properties of Porous Lead Zirconate Titanate Backing for Ultrasonic Transducers

IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control ◽

10.1109/tuffc.2020.2983257 ◽

2020 ◽

Vol 67 (8) ◽

pp. 1656-1666 ◽

Cited By ~ 3

Author(s):

Danjela Kuscer ◽

Julien Bustillo ◽

Tina Bakaric ◽

Silvo Drnovsek ◽

Marc Lethiecq ◽

...

Keyword(s):

Lead Zirconate Titanate ◽

Lead Zirconate ◽

Ultrasonic Transducers ◽

Acoustic Properties ◽

Zirconate Titanate

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Functionally Graded Piezoelectric Ceramics for Ultrasonic Transducers

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.2609 ◽

2007 ◽

Vol 336-338 ◽

pp. 2609-2612

Author(s):

Deng Ren Jin ◽

Zhong Yan Meng ◽

Wen Biao Wu ◽

Bing Qin

Keyword(s):

Lead Zirconate Titanate ◽

Piezoelectric Ceramics ◽

Impedance Analysis ◽

Lead Zirconate ◽

Functionally Graded ◽

Ultrasonic Transducers ◽

Frequency Bandwidth ◽

Gradient Distribution ◽

Structural And Electrical Properties ◽

Functionally Graded Piezoelectric

Functionally graded piezoelectric ceramics (FGM) plates are attractive due to their ability to broaden the frequency bandwidth of the ultrasonic transducers. A resistivity gradient La-doped Lead Zirconate Titanate/Al-doped Zinc Oxide (La-PZT/Al-ZnO) piezoelectric ceramics plate was developed using a powder metallurgical process. Grading of the piezoelectric modulus across the plate was experimentally confirmed by the electrical impedance analysis and its gradient distribution was characterized using the profile-technique. The distribution of Zn2+ ions in the PZT region was examined using EPMA, XRD and SEM/EDX, respectively. Analysis results show that the gradient distributions of structural and electrical properties inside the FGM plate are mainly caused by the diffusion and aggregation of Zn2+ ions in the PZT layer. The functionally graded piezoelectric ceramics plate presented here will be useful for broadening the frequency bandwidth of piezoelectric transducers.

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High-Efficiency Output Pressure Performance Using Capacitive Micromachined Ultrasonic Transducers with Substrate-Embedded Springs

Sensors ◽

10.3390/s18082520 ◽

2018 ◽

Vol 18 (8) ◽

pp. 2520 ◽

Cited By ~ 5

Author(s):

Byung Lee ◽

Amin Nikoozadeh ◽

Kwan Park ◽

Butrus Khuri-Yakub

Keyword(s):

Lead Zirconate Titanate ◽

High Efficiency ◽

Transmission Efficiency ◽

Ultrasonic Transducers ◽

Parallel Plates ◽

Displacement Efficiency ◽

Average Volume ◽

Capacitive Micromachined Ultrasonic Transducers ◽

Output Pressure ◽

Maximum Transmission

Capacitive micromachined ultrasonic transducers (CMUTs) with substrate-embedded springs offer highly efficient output pressure performance over conventional CMUTs, owing to their nonflexural parallel plate movement. The embedded silicon springs support thick Si piston plates, creating a large nonflexural average volume displacement efficiency in the operating frequency range from 1–3 MHz. Static and dynamic volume displacements of the nonflexural parallel plates were examined using white light interferometry and laser Doppler vibrometry. In addition, an output pressure measurement in immersion was performed using a hydrophone. The device showed a maximum transmission efficiency of 21 kPa/V, and an average volume displacement efficiency of 1.1 nm/V at 1.85 MHz with a low DC bias voltage of 55 V. The device element outperformed the lead zirconate titanate (PZT) ceramic HD3203, in the maximum transmission efficiency or the average volume displacement efficiency by 1.35 times. Furthermore, its average volume displacement efficiency reached almost 80% of the ideal state-of-the-art single-crystal relaxor ferroelectric materials PMN-0.33PT. Additionally, we confirmed that high-efficiency output pressure could be generated from the CMUT device, by quantitatively comparing the hydrophone measurement of a commercial PZT transducer.

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Electrical and optical properties of Lead Zirconate Titanate composite films used in flexible high temperature ultrasonic transducers.

2011 IEEE International Ultrasonics Symposium ◽

10.1109/ultsym.2011.0209 ◽

2011 ◽

Author(s):

J.-L. Shih ◽

M. C.-K. Cheung ◽

S. E. Kruger ◽

C.-K. Jen

Keyword(s):

Optical Properties ◽

High Temperature ◽

Lead Zirconate Titanate ◽

Composite Films ◽

Lead Zirconate ◽

Ultrasonic Transducers ◽

Electrical And Optical Properties ◽

Zirconate Titanate

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Flexible Thin-Film PZT Ultrasonic Transducers on Polyimide Substrates

Sensors ◽

10.3390/s21031014 ◽

2021 ◽

Vol 21 (3) ◽

pp. 1014

Author(s):

Tianning Liu ◽

Ajay Dangi ◽

Jeong Nyeon Kim ◽

Sri-Rajasekhar Kothapalli ◽

Kyusun Choi ◽

...

Keyword(s):

Thin Film ◽

Lead Zirconate Titanate ◽

Sound Pressure ◽

Lead Zirconate ◽

Ultrasonic Transducers ◽

Driving Voltage ◽

Si Substrates ◽

Pzt Films ◽

Solution Cast ◽

Pressure Output

We report flexible thin-film lead zirconate titanate (PZT)-based ultrasonic transducers on polyimide substrates. The transducers are bar resonators designed to operate in the width extension mode. The active elements are 1 µm thick PZT films that were crystallized on Si substrates at 700 °C and transferred to 5 µm thick solution-cast polyimide via dissolution of an underlying release layer. Underwater pitch–catch testing between two neighboring 100 µm × 1000 µm elements showed a 0.2 mV signal at a 1.5 cm distance for a driving voltage of 5 V peak at 9.5 MHz. With the same excitation, a 33 kPa sound pressure output at a 6 mm distance and a 32% bandwidth at −6 dB were measured by hydrophone.

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Convergent-bceam diffraction studies on lead zirconate titanate Ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143961 ◽

1986 ◽

Vol 44 ◽

pp. 482-483

Author(s):

M.L.A. Dass ◽

T.A. Bielicki ◽

G. Thomas ◽

T. Yamamoto ◽

K. Okazaki

Keyword(s):

Lead Zirconate Titanate ◽

Direct Proof ◽

Lead Zirconate ◽

Subsolidus Phase ◽

Pzt Ceramics ◽

Subsolidus Phase Diagram ◽

Zirconate Titanate ◽

Two Phases ◽

Cbd Method ◽

Titanate Ceramics

Lead zirconate titanate, Pb(Zr,Ti)O3 (PZT), ceramics are ferroelectrics formed as solid solutions between ferroelectric PbTiO3 and ant iferroelectric PbZrO3. The subsolidus phase diagram is shown in figure 1. PZT transforms between the Ti-rich tetragonal (T) and the Zr-rich rhombohedral (R) phases at a composition which is nearly independent of temperature. This phenomenon is called morphotropism, and the boundary between the two phases is known as the morphotropic phase boundary (MPB). The excellent piezoelectric and dielectric properties occurring at this composition are believed to.be due to the coexistence of T and R phases, which results in easy poling (i.e. orientation of individual grain polarizations in the direction of an applied electric field). However, there is little direct proof of the coexistence of the two phases at the MPB, possibly because of the difficulty of distinguishing between them. In this investigation a CBD method was found which would successfully differentiate between the phases, and this was applied to confirm the coexistence of the two phases.

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