WORKSHOP PAPER
Near-infrared sensitivity enhancement of silicon photodiode with plasmonic grating
Abstract
We have proposed plasmonic diffraction for enhancement of near-infrared (NIR) sensitivity in a silicon-based image sensor. Metal grating efficiently diffracted incident light into the silicon absorption layer. The silver grating structure was fabricated on a large-area silicon photodiode by a lift-off method. The 1.2-fold improvement in sensitivity by plasmonic diffraction was demonstrated at a NIR wavelength of 940 nm.Keywords
plasmonic diffraction, near-infrared sensitivity, silicon-based image sensor, metal grating,References
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