N-WELL BARRIER PIXELS FOR IMPROVED PROTECTION OF DARK REFERENCE COLUMNS AND ROWS FROM BLOOMING AND CROSSTALK

摘要

The barrier region for isolating one or more dark regions of the pixel array of an image sensor from the active array or from the peripheral circuitry includes N-well pixel isolation region. The N-well pixel isolation region includes at least one N-well implant or at least one N-well stripe. The N-well pixel isolation region is adjacent the pixel cells which comprise the dark region. The addition of the N-well in the barrier region improves the isolation properties of the barrier region by reducing or eliminating the neutral P-EPI region in the barrier pixel area below the N-well isolation region.