A CMOS capacitive pressure sensor chip for fingerprint detection

Author

Hsiung, Yung-Shih ; Lu, Michael S -C

Author_Institution

Dept. of Electr. Eng., Nat. Tsing Hua Univ., Hsinchu, Taiwan

fYear

2011

fDate

5-9 June 2011

Firstpage

24

Lastpage

27

Abstract

Biometric techniques, such as fingerprint detection, can be applied to identify a specific user for security and safety reasons. We present a capacitive fingerprint sensor that can detect the difference of pressures induced by the ridges and valleys of a finger tip. Post-CMOS fabrication of the 8×32 sensor array is conducted based on wet etch of CMOS metal layers without requiring additional thin-film deposition and patterning. The size of each sensing pixel is 65×65 μm². The measured sensor sensitivity was 0.39 fF/MPa. Part of the fingerprint image was successfully produced by the CMOS sensor chip.

Keywords

CMOS image sensors; capacitive sensors; fingerprint identification; pressure sensors; CMOS capacitive pressure sensor chip; CMOS metal layer; biometric technique; fingerprint detection; thin-film deposition; Arrays; CMOS integrated circuits; Capacitance; Fabrication; Fingerprint recognition; Fingers; Sensors; CMOS; capacitive sensor; fingerprint; tactile;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State Sensors, Actuators and Microsystems Conference (TRANSDUCERS), 2011 16th International

Conference_Location

Beijing

ISSN

Pending

Print_ISBN

978-1-4577-0157-3

Type

conf

DOI

10.1109/TRANSDUCERS.2011.5969123

Filename

5969123