Novel Analytical Framework Models Dark Count Probability in Single-Photon Avalanche Diodes
A new analytical framework shows that dark count probability in perimeter-gated single-photon avalanche diodes follows a complementary Gompertz function, enabling deterministic bias control. The model was validated on a 64×64 array of 4,096 devices fabricated in a 0.35 µm CMOS process, tested across temperatures from -5°C to 55°C. This advance could improve the reliability and consistency of single-photon detectors used in applications such as LiDAR, medical imaging, and quantum communication.
Researchers have proposed and experimentally validated a novel analytical framework for modeling dark count probability (PDC) in perimeter-gated single-photon avalanche diodes (pg-SPADs), a key noise metric in single-photon detection. The framework demonstrates that PDC follows a complementary Gompertz function, from which a pixel-specific descriptor called the midpoint perimeter gate voltage is derived to characterize each pixel's equiprobable operating point. Crucially, the model also yields a perimeter gate voltage compensation rate that can offset temperature-induced shifts in a pixel's activation function, addressing a longstanding challenge in detector calibration. Experimental validation was conducted on 4,096 pg-SPADs in a 64×64 array manufactured in a standard 0.35 µm CMOS process, with characterization spanning temperatures of -5°C to 55°C and gate voltage magnitudes of 0 to 5 V. The results demonstrate that deterministic control of dark count probability across process and temperature variations is achievable using this framework. The work is a four-page letter prepared for submission to IEEE Photonics Technology Letters and is currently a preprint on arXiv, meaning it has not yet undergone peer review.
What's missing
As a preprint, this work has not yet completed peer review, so independent replication and expert scrutiny of the methodology and claims are still pending. The study does not report how the compensation scheme performs under dynamic or rapidly fluctuating temperature conditions, nor does it address scalability to larger or finer-geometry CMOS arrays beyond the 0.35 µm process tested.
What different sources said
- arXiv physicsCenter
Modeling of Dark Count Probability in Perimeter-Gated SPADs
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