Collapsed regime operation of capacitive micromachined ultrasonic transducers based on wafer-bonding technique


Huang Y., Haeggstrom E., BAYRAM B., Zhuang X., Ergun A., Cheng C., ...More

IEEE International Ultrasonics Symposium, Hawaii, United States Of America, 5 - 08 October 2003, pp.1161-1164 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Volume:
  • City: Hawaii
  • Country: United States Of America
  • Page Numbers: pp.1161-1164

Abstract

We report experimental results from collapsed regime operation of capacitive micromachined ultrasonic transducers (cMUTs) fabricated by a wafer bonding technique. The results show that a cMUT operating in the collapsed regime produces a maximal output pressure higher than a cMUT operating in the pre-collapse regime at 90 % of its collapse voltage, 1.79 kPa/V vs. 9.72 kPa/V at 2.3 MHz. In collapsed regime operation the fractional bandwidth (pulse echo) is increased compared to that obtained in pre-collapsed regime operation 140 % vs. 83 % with a bias 90 % of the collapse voltage. Characterization of 1-D cMUT arrays operating in oil was done by ultrasonic pulse echo and pitch catch measurements.