MEMS fingerprint sensor with arrayed cavity structures

Author

Sato, N. ; Machida, K. ; Morimura, H. ; Shigematsu, S. ; Kudou, K. ; Yano, M. ; Kyuragi, H.

Author_Institution

NTT Telecommun. Energy Labs, Atsugi, Japan

fYear

2001

fDate

2-5 Dec. 2001

Abstract

We propose a MEMS (Micro Electro Mechanical Systems) fingerprint sensor whose pixels have novel cavity structures. Each cavity structure has a sensitive plane of a thin film on top, and a sensing circuit below it. Ridges on a finger surface bend the thin film mechanically, which is detected by the sensing circuit electronically. We fabricated the sensor using a CMOS compatible process with our sealing technique. The sensor can obtain fingerprint images of even dry or wet fingers. It also shows sufficient mechanical strength against finger pressure. These results confirm that the MEMS fingerprint sensor has the potential for wide practical application.

Keywords

CMOS integrated circuits; fingerprint identification; hot pressing; microsensors; spin coating; surface topography measurement; CMOS compatible process; MEMS fingerprint sensor; arrayed cavity structures; dry fingers; finger surface ridges; hot pressing; mechanical strength; sealing technique; sensing circuit; spin coating film transfer; thin film bending; thin film sensitive plane; wet fingers; CMOS image sensors; CMOS process; Fingerprint recognition; Fingers; Mechanical sensors; Mechanical systems; Micromechanical devices; Sensor arrays; Sensor systems; Thin film circuits;

fLanguage

English

Publisher

ieee

Conference_Titel

Electron Devices Meeting, 2001. IEDM '01. Technical Digest. International

Conference_Location

Washington, DC, USA

Print_ISBN

0-7803-7050-3

Type

conf

DOI

10.1109/IEDM.2001.979661

Filename

979661