Capacitive micromachined ultrasonic transducers (CMUTs) with isolation posts

Author

Huang, Yongli ; Haeggström, Edward O. ; Zhuang, Xuefeng ; Ergun, Arif S. ; Khuri-Yakub, Butrus T.

Author_Institution

Edward L. Ginzton Lab., Stanford Univ., CA, USA

Volume

3

fYear

2004

fDate

23-27 Aug. 2004

Firstpage

2223

Abstract

We report on a capacitive micromachined ultrasonic transducer (CMUT) featuring isolation posts (PostCMUT) to solve a device reliability problem caused by charging during fabrication and operation, and to extend the device operation range beyond collapse voltage. 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 earlier CMUT designs. The PostCMUTs showed no hysteresis during membrane-post contact.

Keywords

capacitive sensors; dielectric hysteresis; micromechanical devices; piezoelectric transducers; reliability; ultrasonic transducers; wafer bonding; CMUT; capacitive charging; capacitive micromachined ultrasonic transducer; collapse voltage; device reliability problem; hysteresis; isolation posts; piezoelectric transducers; wafer-bonding technique; Biomembranes; Dielectrics; Electrodes; Fabrication; Hysteresis; Laboratories; Silicon; Testing; Ultrasonic transducers; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Ultrasonics Symposium, 2004 IEEE

ISSN

1051-0117

Print_ISBN

0-7803-8412-1

Type

conf

DOI

10.1109/ULTSYM.2004.1418281

Filename

1418281