Title :
A solution to the charging problems in capacitive micromachined ultrasonic transducers
Author :
Huang, Yongli ; Hæggström, Edward O. ; Zhuang, Xuefeng ; Ergun, Arif S. ; Khuri-Yakub, Butrus T.
Author_Institution :
Edward L. Ginzton Lab., Stanford Univ., CA, USA
fDate :
4/1/2005 12:00:00 AM
Abstract :
We report on a capacitive micromachined ultrasonic transducer (CMUT) featuring isolation posts (PostCMUT) as a solution to the charging problems caused by device fabrication and operation. This design improves the device reliability. The PostCMUTs were fabricated using a newly developed process based on the wafer-bonding technique. Paired tests showed the superior reliability characteristics of the PostCMUT design compared to those of conventional CMUT designs. No deleterious effect of the new design was seen in preliminary ultrasonic tests or in process yield. PostCMUTs, a design that serves as a solution to the aforementioned reliability problem, constitutes a major contribution to CMUT commercialization.
Keywords :
capacitive sensors; micromachining; reliability; ultrasonic transducers; wafer bonding; CMUT commercialization; capacitive micromachined ultrasonic transducers; charging problems; deleterious effect; device fabrication; device operation; isolation posts; paired tests; process yield; reliability; ultrasonic tests; wafer-bonding technique; Biomembranes; Capacitance; Commercialization; Dielectrics; Electrodes; Electrostatics; Fabrication; Shape; Testing; Ultrasonic transducers;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
DOI :
10.1109/TUFFC.2005.1428039
