Patent ID: 8541825
Filing Date: 2013-09-24
Classification: H01L

Abstract:
1. An image sensor, comprising: a gate structure formed on a semiconductor layer of a first conductive type; a first impurity region of the first conductive type aligned with one side of the gate structure and extending from a surface portion of the semiconductor layer to a first depth; a second impurity region of the first conductive type, extending from the surface portion of the semiconductor layer to a second depth that is deeper than the first depth; a third impurity region of the first conductive type extending from the surface portion of the semiconductor layer to a third depth that is deeper than the second depth; a fourth impurity region of a second conductive type beneath the third impurity region; and a floating diffusion region of the second conductive type aligned with the other side of the gate structure and extending to a predetermined depth from another surface portion of the semiconductor layer; wherein the second conductive type is different than the first conductive type; wherein the first impurity region, the second impurity region, the third impurity region, and the fourth impurity region form a photodiode of the image sensor; and wherein the gate is configured to transfer charge collected by the photodiode to the floating diffusion region in response to a control signal.