WORKSHOP PAPER
A 0.45um-pitch Photodiode Based 1-layer Dual Pixel for CMOS Image Sensor with High Full-Well Capacity and Low Noise
Abstract
In this paper, we developed the 0.9um (0.45um×0.9um×2) dual pixel-based tetra CMOS image sensor (CIS) with full-depth deep trench isolation (FDTI). In spite of the reduced pixel area, characteristics are similar to the 1.0um based FDTI dual pixel by incorporating the novel isolation structure. We implemented asymmetric deep trench isolation (DTI) which led to the simultaneous improvement of high full well capacity (FWC) over 16,000e- and in-pixel overflow path with preserving signal linearity. In addition, the inevitable coupling problem between adjacent pixels according to the pixel shrink is completely restrained by the contact wall isolation structure.Keywords
Photodiode, Dual Pixel, CMOS Image Sensor, Full-Well Capacity, Low Noise,References
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