Self-focused ZnO transducers for ultrasonic biomicroscopy

J. M. Cannata, J. A. Williams, Q. F. Zhou, Lei Sun, K. K. Shung, H. Yu, E. S. Kim

Research output: Journal article publicationJournal articleAcademic researchpeer-review

20 Citations (Scopus)


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 μm 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 μm 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.
Original languageEnglish
Article number084109
JournalJournal of Applied Physics
Issue number8
Publication statusPublished - 9 May 2008
Externally publishedYes

ASJC Scopus subject areas

  • Physics and Astronomy(all)

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