A solution to the charging problems in capacitive micromachined ultrasonic transducers.
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.
Huang
Yongli
Y
Haeggström
Edward O
EO
Zhuang
Xuefeng
X
Ergun
Arif S
AS
Khuri-Yakub
Butrus T
BT