Self-focused ZnO transducers for ultrasonic biomicroscopy

Journal Article · Tue Apr 15 04:00:00 EDT 2008 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.2907716· OSTI ID:21137170

Cannata, J M; Williams, J A; Zhou, Q F; Sun, L; Shung, K K ^[1]; Yu, H ^[2]; Kim, E S ^[3]

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1. NIH Resource Center for Medical Ultrasonic Transducer Technology, Department of Biomedical Engineering, University of Southern California, Los Angeles, California 90089 (United States)
2. Department of Electrical Engineering, School of Earth and Space Exploration, Arizona State University, Tempe, Arizona 85287 (United States)
3. Department of Electrical Engineering and Electrophysics, University of Southern California, Los Angeles, California 90089 (United States)

A simple fabrication technique was developed to produce high frequency (100 MHz) self-focused single element transducers with sputtered zinc oxide (ZnO) crystal films. This technique requires the sputtering of a ZnO film directly onto a curved backing substrate. Transducers were fabricated by sputtering an 18 {mu}m thick ZnO layer on 2 mm diameter aluminum rods with ends shaped and polished to produce a 2 mm focus or f-number equal to one. The aluminum rod served a dual purpose as the backing layer and positive electrode for the resultant transducers. A 4 {mu}m Parylene matching layer was deposited on the transducers after housing and interconnect. This matching layer was used to protect the substrate and condition the transfer of acoustic energy between the ZnO film and the load medium. The pulse-echo response for a representative transducer was centered at 101 MHz with a -6 dB bandwidth of 49%. The measured two way insertion loss was 44 dB. A tungsten wire phantom and an adult zebrafish eye were imaged to show the capability of these transducers.

• OSTI ID: 21137170
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 8 Vol. 103; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ACOUSTIC MICROSCOPY
ALUMINIUM
CRYSTALS
DEPOSITION
FABRICATION
LAYERS
MHZ RANGE 01-100
PHANTOMS
RODS
SEMICONDUCTOR MATERIALS
SPUTTERING
SUBSTRATES
THIN FILMS
TRANSDUCERS
TUNGSTEN
ULTRASONOGRAPHY
ZINC OXIDES