摘要 |
An image sensor architecture for an active pixel sensor array are separated and arranged vertically in at least two different layers in a hybrid chip structure. The top layer includes the photodiode and amplifier circuitry for each pixel. A bottom includes the pixel circuit components and any digital circuitry required for signal processing. By forming the top layer in a process optimized for forming low-noise pixels, the pixel performance can be greatly improved. In addition, since the digital circuitry is now separated from the imaging circuitry, it can be formed using a process which has been optimized for circuit speed and manufacturing cost. By combining the two layers into a stacked structure, the top layer (and any intermediate layer(s)) acts to optically shield the lower layer, thereby allowing charge to be stored and shielded without the need for a mechanical shutter. |