Title :
Fingerprint imager based on a-Si:H active-matrix photo-diode arrays
Author :
Lan, J. ; Cole, A. ; VanZandt, J. ; Dickinson, A. ; van de Ven, F. ; Bird, N. ; Badano, A. ; Kanicki, J.
Author_Institution :
Ethentica Inc., Lake Forest, CA, USA
Abstract :
We present a thin-format optical fingerprint image sensor based on hydrogenated amorphous silicon (a-Si:H) n-i-p photo-diode technology. The fingerprint sensor has resolution of 403 dpi. Optical Monte Carlo simulations and experimental data obtained for an edge-light illuminated sensor structure shows that the fingerprint image is formed by total internal reflection (TIR) of photons in finger skin valleys. Conversely, for a back-light illuminated sensor structure the image is formed by reflection of photons in finger skin ridges. Finally, a fingerprint sensor prototype has been built to demonstrate these two types of sensor technology.
Keywords :
Monte Carlo methods; amorphous semiconductors; elemental semiconductors; fingerprint identification; hydrogen; image sensors; p-i-n photodiodes; silicon; tactile sensors; Si:H; active-matrix photodiode arrays; back-light illuminated sensor; biometrics; edge-light illuminated sensor; finger skin ridges; finger skin valleys; fingerprint sensor; hydrogenated amorphous silicon; n-i-p photodiode technology; optical Monte Carlo simulations; thin-format optical fingerprint imager; total internal reflection of photons; Active matrix technology; Amorphous silicon; Fingerprint recognition; Fingers; Image matching; Image sensors; Optical reflection; Optical sensors; Optoelectronic and photonic sensors; Skin;
Conference_Titel :
Electron Devices Meeting, 2000. IEDM '00. Technical Digest. International
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-7803-6438-4
DOI :
10.1109/IEDM.2000.904345
