Sonavation shows world's thinnest fingerprint sensor

Published 25 March 2009

Florida-based Sonavation shows innovative — and very small — fingerprint sensor: 35 mm in length by 14.5 mm wide with a thickness of only 0.25 mm; the sensing element alone is only 3 mm in length by 14 mm wide by 0.1 mm thick

Palm Beach Gardens, Florida-based Sonavation is showing what it claims to be the biometrics industry’s thinnest fingerprint sensor for the wireless and smartcard markets. The SonicSlide STS3000 is about the thickness of a postage stamp, and is constructed from polymers similar to those used to build wings of commercial aircraft.

The SonicSlide STS3000 uses the patented SonicTouch technology, which is based on ultrasound comparable to that used in medical applications. The company says the technology significantly improves fingerprint imaging. Because it is not a semiconductor, the sensor eliminates the electrostatic discharge (ESD) problems that have hampered the incorporation of semiconductor-based sensors into notebook PCs, mobile phones, and other consumer electronics.

The company says the SonicSlide STS3000 can withstand more than 10 million swipes and uses less power, thus enabling a set of applications that currently is not addressed within the commercial biometrics industry.

Sonavation has developed new biometrics technology that is certain to revolutionize the industry by delivering higher quality and reliability at a much more competitive price,” said Sonavation chairman and CEO Ted Johnson. “To develop and bring to market such robust technology in such a relatively short period of time is testament of our management team’s considerable understanding of the biometrics market.”

Steve Mansfield, Sonavation president and COO, said that “The SonicSlide STS30000 is the biometrics industry’s most technologically advanced fingerprint sensor. Sonavation is positioned to be a leader in the burgeoning billion-dollar financial transaction business and the 1.1-billion unit mobile handset market. A host of applications capabilities is now available that were not previously addressed by currently available fingerprint sensors.”


The ultrasound principles on which SonicSlide STS3000 is based allows for greater accuracy of fingerprint images than that achieved through DC or RF capacitive silicon sensors. Silicon-based sensors may be damaged through electrostatic discharge (ESD), but the SonicSlide STS3000 is based on composite ceramic MEMS technology, which is not affected by ESD.

The fingerprint sensor module is an array of ceramics MEMS piezoelectric transducers and advanced polymers combined with a silicon-imaging ASIC. All of these components are integrated into a single package about 35 mm in length by 14.5 mm wide with a thickness of only 0.25 mm. The sensing element alone is only 3 mm in length by 14 mm wide by 0.1 mm thick.

The key imaging component of the sensor is the ceramic MEMS piezoelectric transducer array that is made from a ceramic material. This material is formed into pillars, each one-tenth the thickness of a human hair. The pillars have a unique set of properties that enable them to oscillate mechanically when an electric field is applied. The oscillations then register in 256 shades of gray to form the images of ridges and valleys of the fingerprint. The company says that this ensures a level of accuracy that cannot be achieved by most other swipe sensor technologies, including semiconductor-based sensors.

The SonicSlide STS3000 is designed with a ZIF interconnect scheme for integration into virtually any mobile handset platform.