Thin and flexible scanner
reads fingerprints from nail to nail

TNO at Holst Centre, Solliance and TU/e worked together in the development of a thin and flexible scanner for fingerprints. Low-resolution image-sensor arrays have been demonstrated in the past, but the step toward high-resolution, high pixel-count image sensors suitable for commercial applications has been lacking to date. Gerwin Gelinck and Albert van Breemen took the flexible fingerprint scanner to the next level, and now have an article published on this subject in the current edition of Nature Electronics.

Efficient and cost-effective

The thin and flexible scanner is based on metal-halide perovskites. Perovskites are currently transforming the global solar panel market. They are as efficient as silicon, but are cost-effective and easy to produce on a large scale. Gerwin Gelinck, Chief Technology Officer TNO at Holst Centre, elaborates on the article in Nature Electronics: "Perovskites are marvelous materials! For the first time we show that these materials are also very good for light imaging and sensing applications. When combined with display-like transistors, we made a scanner that can capture high-resolution colour images as well as biometric fingerprinting".

Metal-halide perovskites (MHPs) possess excellent opto-electronic properties, such as a broad light-absorption range and tuneable bandwidths, a high extinction coefficient, high charge-carrier mobility and long electron-hole diffusion lengths. As a result, the materials have been used as photo-active layers in solar cells, light-emitting diodes, lasers and photodetectors. They are also well-suited to low-cost, large-area solution processing, making them ideal candidates to replace commercial silicon semiconductors in photodetection applications such as image sensing, optical communication, environmental monitoring, and chemical or biological detection.

 High resolution fingerprint sensing & Scanning of color image (top: original, bottom: scanned image)

The adoption of this technology may be accelerated by tailoring the electro-optical properties of perovskites, as well as upscaling to larger active areas by using slot-die coating, for example. Light-sensing across both the visible and infrared spectrum could be enhanced, leading to improved applications in medical imaging, surveillance, and optical communication.

Gerwin and Albert conclude:

"We very much look forward to seeing where this technology will take us next."

Are you interested in this technology?

Do you want to explore the possibilities with us? Then don't hesitate to contact us:

Gerwin Gelinck
Chief Technology Officer TNO at Holst Centre
gerwin.gelinck@tno.nl

Albert van Breemen
Senior Scientist TNO at Holst Centre:
albert.vanbreemen@tno.nl