Novel Analytical Framework Models Dark Count Probability in Single-Photon Avalanche Diodes
Researchers have developed an analytical framework showing that dark count probability in perimeter-gated single-photon avalanche diodes (pg-SPADs) follows a complementary Gompertz function, enabling better characterization of pixel performance. The framework introduces a pixel-specific descriptor called midpoint perimeter gate voltage that identifies optimal operating points and allows compensation for temperature-induced variations. This advance is significant for improving the reliability and performance of single-photon detection systems used in quantum computing, medical imaging, and other precision applications.
A new analytical model demonstrates that dark count probability in perimeter-gated single-photon avalanche diodes follows a complementary Gompertz mathematical function. The researchers derived a pixel-specific descriptor, the midpoint perimeter gate voltage, which characterizes each pixel's equiprobable operating point and enables compensation for temperature-induced changes in activation function. The framework was experimentally validated using a 64 x 64 array of 4,096 pg-SPADs manufactured in a 0.35 micrometer CMOS process, with devices tested across temperatures from -5°C to 55°C and perimeter gate voltages from 0 to 5 V. The measured results demonstrate deterministic bias control of dark count probability across process and temperature variations, addressing a key challenge in single-photon detector reliability. This work is prepared for submission to IEEE Photonics Technology Letters.
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- arXiv physicsCenter
Modeling of Dark Count Probability in Perimeter-Gated SPADs
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