title: High-frequency (>50 MHz) medical ultrasound linear arrays fabricated from micromachined bulk PZT materials.
abstract: This paper describes the development and characterization of a high-frequency (65-MHz) ultrasound transducer linear array. The array was built from bulk PZT which was etched using an optimized chlorine-based plasma dry-etching process. The median etch rate of 8 µ m/h yielded a good profile (wall) angle (>83°) and a reasonable processing time for etch depths up to 40 μm (which corresponds to a 50-MHz transducer). A backing layer with an acoustic impedance of 6 MRayl and a front-end polymer matching layer yielded a transducer bandwidth of 40%. The major parameters of the transducer have been characterized. The two-way insertion loss and crosstalk between adjacent channels at the center frequency are 26.5 and -25 dB, respectively.
authors.forename: Changgeng
authors.initials: C
authors.lastname: Liu
authors.forename: Qifa
authors.initials: Q
authors.lastname: Zhou
authors.forename: Frank T
authors.initials: FT
authors.lastname: Djuth
authors.forename: K Kirk
authors.initials: KK
authors.lastname: Shung
mesh_terms: D002516:Ceramics / Q000737:chemistry* / Q000528:radiation effects; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007089:Image Enhancement / Q000295:instrumentation*; D007854:Lead / Q000737:chemistry* / Q000528:radiation effects; D008422:Materials Testing; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation*; D046228:Microarray Analysis / Q000295:instrumentation*; D008904:Miniaturization; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014025:Titanium / Q000737:chemistry* / Q000528:radiation effects; D014463:Ultrasonography / Q000295:instrumentation*; D015040:Zirconium / Q000737:chemistry* / Q000528:radiation effects
chemical_list: C065536:lead titanate zirconate; D007854:Lead; D015040:Zirconium; D014025:Titanium