WORKSHOP PAPER
Charge Transfer Noise in Image Sensors
Abstract
Charge transfer noise often limits the performance of image sensors when read noise is reduced to below 2e- RMS. In this paper, the analysis of charge transfer noise in a 4T CMOS image sensor using a simple 1-D model is presented, investigating incomplete charge transfer noise, and determining it as not a significant source. The study concludes that the most probable source of transfer noise in 4T CMOS image sensors is charge trapping and detrapping at the Si–SiO2 interface during the charge transfer process, proposing a model for analyzing this noise based on a random sum of random telegraph signals.Keywords
charge transfer noise, 4T CMOS image sensor, Si-SiO2 interface,References
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