Capacitive micromachined ultrasonic transducers (CMUTs) with isolation posts

被引：26

作者：

Huang, Yongli ^{[2
]}

Zhuang, Xuefeng ^{[1
]}

Haeggstrom, Edward O. ^{[3
]}

Ergun, A. Sanli ^{[4
]}

Cheng, Ching-Hsiang ^{[5
]}

Khuri-Yakub, Butrus T. ^{[1
]}

机构：

[1] Stanford Univ, Edward L Ginzton Lab, Stanford, CA 94305 USA

[2] Kolo Technol Inc, San Jose, CA USA

[3] Univ Helsinki, Elect Res Unit, Helsinki, Finland

[4] Siemens Corp Res, Mountain View, CA USA

[5] Hong Kong Polytech Univ, Res Inst Innovat Prod & Technol, Hong Kong, Hong Kong, Peoples R China

来源：

ULTRASONICS | 2008年 / 48卷 / 01期

基金：

芬兰科学院; 美国国家科学基金会; 美国国家卫生研究院;

关键词：

ultrasound; transducer; CMUT; isolation posts; charging; hysteresis; reliability;

D O I：

10.1016/j.ultras.2007.11.006

中图分类号：

O42 [声学];

学科分类号：

070206 ; 082403 ;

摘要：

In this paper, an improved design of a capacitive micromachined ultrasonic transducer (CMUT) is presented. The design improvement aims to address the reliability issues of a CMUT and to extend the device operation beyond the contact (collapse) voltage. The major design novelty is the isolation posts in the vacuum cavities of the CMUT cells instead of full-coverage insulation layers in conventional CMUTs. This eliminates the contact voltage drifting due to charging caused by the insulation layer, and enables repeatable CMUT operation in the post-contact regime. Ultrasonic tests of the CMUTs with isolation posts (PostCMUTs) in air (electrical input impedance and capacitance vs. bias voltage) and immersion (transmission and reception) indicate acoustic performance similar to that obtained from conventional CMUTs while no undesired side effects of this new design is observed. (C) 2007 Elsevier B.V. All rights reserved.

引用

页码：74 / 81

页数：8

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