WORKSHOP PAPER
Analysis of Dark Current in 4-Transistor CMOS Imager Pixel with Negative Transfer-gate bias Operation
Abstract
Dark current mechanisms in a 4-Transistor CMOS imager pixel with a negative gate bias on a transfer gate have been investigated. The increase of dark current with the negative gate bias has been attributed to the Gate-Induced-Leak (GIL) Trap Assisted Tunneling (TAT) by examining dark current dependency both on negative gate bias and on temperature. The negative gate bias on a transfer gate efficiently reduces Shockley-Read-Hall (SRH) dark current but generates GIL-TAT dark current when large negative gate bias is applied.Keywords
Dark Current, 4-Transistor CMOS Imager, Negative Gate Bias,References
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