This paper reports on characterization results of a single-photon avalanche diode (SPAD) array in standard CMOS 150nm technology. The array is composed by 25 (5 × 5) SPADs, based on p/n-well active junction along with a retrograde deep n-well guard ring. The square-shaped SPAD has a 10µm active diameter and 15.6µm pitch size, achieving a 39.9% array fill factor. Characterization results show a good breakdown voltage uniformity (40mV max-min) within each chip and 17mV/°C temperature coefficient. The median DCR is 0.4Hz/µm, and the afterpulsing probability is 0.85% for a dead time of 150ns at 3V excess bias voltage. The peak PDP is 31% at 450nm wavelength and a good uniformity (1.1% standard deviation) is observed for the array at 5V excess bias. The single SPADs exhibit a timing jitter of 52ps (FWHM) and 42ps (FWHM) under a 468-nm and a 831-nm laser, respectively. The crosstalk probability as a function of pixel-to-pixel distance and excess bias voltage is presented, and random telegraph signal (RTS) noise is also discussed in detail.
In this paper, a summary of characterization results from a SPAD test chip is reported. The chip includes test arrays based on two different SPAD structures, having p+/n-well and p-well/n-iso active area. Devices with different shapes and sizes as well as arrays dedicated to cross-talk extraction are present. Measurement results show that SPADs of the second type have a slightly lower Dark Count Rate. The peak Photon Detection Probability (PDP) is larger than 20% at 3V excess bias voltage for both structures. The average cross-talk probability between neighbors in SPAD arrays with 15.6μm pitch and 40% fill factor is less than 0.6% at 3V excess bias voltage for the first structure, while it is around 2.3% for the second one.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.