A pixel-shared CMOS image sensor using lateral overflow gate

A lateral overflow integration capacitor (LOFIC) based CMOS image sensor sharing two pixels and without row-select transistors has been developed using a newly added lateral overflow gate which directly connects the photodiode and the LOFIC. A 0.18-µm, 2-Poly 3-Metal CMOS technology with a buried pinned photodiode process was employed for the fabrication of the CMOS image sensor having 1/3.3-inch optical format, 1280<sup>H</sup> × 960<sup>V</sup> pixels, and RGB Bayer color filter and on-chip micro-lens on each pixel. The fabricated CMOS image sensor exhibits a high conversion gain of 84-µV/e<sup>-</sup> and a high full well capacity of 6.9 × 10<sup>4</sup>-e<sup>-</sup> in spite of its pixel size of 3.0 × 3.0-µm<sup>2</sup>.

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