Patent ID: 11309348

Abstract:
The present disclosure relates to a CMOS image sensor having a doped isolation structure separating a photodiode and a pixel device, and an associated method of formation. In some embodiments, the CMOS image sensor has a doped isolation structure separating a photodiode and a pixel device. The photodiode is arranged within the substrate away from a front-side of the substrate. A pixel device is disposed at the front-side of the substrate overlying the photodiode and is separated from the photodiode by the doped isolation structure. Comparing to previous image sensor designs, where an upper portion of the photodiode is commonly arranged at a top surface of a front-side of the substrate, now the photodiode is arranged away from the top surface and leaves more room for pixel devices. Thus, a larger pixel device can be arranged in the sensing pixel, and short channel effect and noise level can be improved.