A Study of Crosstalk in a 256 \times 256 Photon Counting Imager Based on Silicon Geiger-Mode Avalanche Photodiodes

• Published in: IEEE sensors journal Vol. 15; no. 4; pp. 2123 - 2132
• Main Authors: Aull, Brian F., Schuette, Daniel R., Young, Douglas J., Craig, David M., Felton, Bradley J., Warner, Keith
• Format: Journal Article
• Language: English
• Published: IEEE 01-04-2015
• Subjects: Arrays; avalanche photodiodes; breakdown voltage; CMOS integrated circuits; Crosstalk; dark count rate; Detectors; diodes; Geiger mode; Image sensors; p-n junctions; photodetectors; Photonics; quantum efficiency; signal detection; Silicon; single-photon avalanche diodes; single-photon detection; singlephoton counting; SPAD array; p-n junctions; signal detection; single-photon detection; diodes; single-photon counting; detectors; Image sensors; photodetectors; silicon; avalanche photodiodes; quantum efficiency; single-photon avalanche diodes; breakdown voltage; SPAD array; dark count rate; Geiger-mode
• ISSN: 1530-437X; 1558-1748
• DOI: 10.1109/JSEN.2014.2368456

We demonstrate a 256 × 256 passive photon counting imager based on hybridization of back-illuminated silicon Geiger-mode avalanche photodiodes to an all-digital CMOS counting chip. Photon detection efficiencies in the 10%-20% are observed at visible wavelengths. The detection efficiency is currently limited by optical crosstalk that leads to elevation of dark count rates as the bias voltage on the photodiodes is increased. Both the time dependence of dark count activity during a gate time and the spatial structure of dark images were successfully explained using crosstalk-based models.