WORKSHOP PAPER
A 3D stacked CMOS image sensor with 16Mpixel global-shutter mode using 4 million interconnections
Abstract
We have developed a 16Mpixel 3D stacked global-shutter CMOS image sensor with pixel level interconnections using 4 million micro bumps. The four photodiodes in the unit pixel circuit on the top substrate share one micro-bump interconnection at a 7.6μm pitch. Each signal of the photodiodes is transferred to the corresponding storage node on the bottom substrate via the interconnection to achieve a global shutter function. Those storage nodes on the bottom substrate are not just protected from incident light but also photo generated carriers. The ratio of the parasitic light sensitivity of an in-pixel storage node and the light sensitivity of a photodiode is -180dB with 3.8μm pixel size, which is smaller than our previous work and prevents any artifact by bright moving objects in the scenes for DSC usage.Keywords
3D stacked CMOS image sensor, 16Mpixel global-shutter mode, micro bump interconnections,References
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