WORKSHOP PAPER
Silicon integrated electrical micro-lens for CMOS SPADs based on avalanche propagation phenomenon
Abstract
The design and fabrication of integrated micro-lenses for CMOS single-photon avalanche diodes (SPADs) are presented in this paper. The micro-lens exploits the avalanche propagation phenomenon occurring in abrupt single-sided junctions and is achieved by careful design of the SPAD in a standard CMOS process. Unlike an optical micro-lens, the proposed technique is more robust to manufacturing tolerances and can scale to large arrays, providing a better concentration factor and uniformity. Measurement results show a photon detection probability (PDP) as high as 64.85% at 600 nm when the SPAD is biased at 2 V of excess bias.Keywords
CMOS SPADs, Avalanche propagation phenomenon, Integrated micro-lenses,References
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