| 摘要 |
An imaging system may include an image sensor having an array of image pixels formed in a substrate. Each image pixel may include a photodiode directly coupled to an anti-blooming diode. The anti-blooming diode may be connected to a positive voltage supply line and may be configured to drain excess charge from the photodiode when the photodiode is saturated. The anti-blooming drain may be formed from an n-type diffusion region partially surrounded by a p-type doped layer. The p-type doped layer may be interposed between and in contact with the n-type diffusion region of the anti-blooming diode and an n-type doped region of the photodiode. The anti-blooming diode may begin to drain excess charge from the photodiode in response to the photodiode reaching a threshold potential during integration. If desired, multiple pixels may share a common anti-blooming diode. |
