Patent ID: 11961868
Assignee: STMICROELECTRONICS (CROLLES 2) SAS
Field: Audio-visual technology (Electrical engineering)
Classification: CPC H | IPC H

Claim 7:
8. A method, comprising:
in an integration mode:
biasing a vertical annular transfer gate laterally framing a read node and an upper portion of a first doped photosensitive region to block charge transfer from the first doped photosensitive region to the read node;
biasing a first vertical annular gate laterally framing the first doped photosensitive region and surrounding the vertical annular transfer gate to form a first potential well in a remainder of the first doped photosensitive region which collects first integrated photogenerated charge;
biasing a second vertical annular gate laterally framing the second doped photosensitive region and surrounding the first vertical annular gate to form a second potential well in the second doped photosensitive region which collects second integrated photogenerated charge; and

in an intensity read-out transfer mode:
a) biasing said first vertical annular gate to empty second integrated photogenerated charge from the second potential well to be added to the first integrated photogenerated charge at said first potential well; and
b) biasing said vertical annular transfer gate to permit charge transfer from the first doped photosensitive region to the read node and empty said added first and second integrated photogenerated charge from the first potential well to the read node.