IMAGE SENSOR PIXEL FOR HIGH DYNAMIC RANGE IMAGE SENSOR

摘要

An image sensor pixel includes a first photodiode and a second photodiode disposed in a semiconductor material. The first photodiode has a first doped region, a first lightly doped region, and a first highly doped region. The second photodiode has a second full well capacity substantially equal to a first full well capacity of the first photodiode, and includes a second doped region, a second lightly doped region, and a second highly doped region. The image sensor pixel also includes a first microlens optically coupled to direct a first amount of image light to the first photodiode, and a second microlens optically coupled to direct a second amount of image light to the second photodiode. The first amount of image light is larger than the second amount of image light.

主权项

1. An image sensor pixel for use in a high dynamic range image sensor, the image sensor pixel comprising:
a first photodiode disposed in a semiconductor material, the first photodiode including a first doped region, a first lightly doped region, and a first highly doped region disposed between the first doped region and the first lightly doped region, wherein the first doped region is doped opposite of the first lightly doped region and the first highly doped region, and wherein the first highly doped region has a higher first dopant concentration than the first lightly doped region, and wherein the first doped region is positioned to receive image light before the first highly doped region receives the image light; a second photodiode disposed in the semiconductor material and having a second full well capacity substantially equal to a first full well capacity of the first photodiode, the second photodiode including a second doped region, a second lightly doped region, and a second highly doped region disposed between the second doped region and the second lightly doped region, wherein the second doped region is doped the same polarity as the first doped region but opposite of the second lightly doped region and the second highly doped region, and wherein the second highly doped region has a higher second dopant concentration than the second lightly doped region, the first highly doped region and the second highly doped region being substantially the same size and shape and having substantially equal dopant concentrations, and wherein the second doped region is positioned to receive the image light before the second highly doped region receives the image light; a first microlens optically coupled to direct a first amount of image light to the first photodiode; and a second microlens optically coupled to direct a second amount of image light to the second photodiode, wherein the first amount of image light is larger than the second amount of image light.