4T CMOS Image Sensor Pixel Degradation due to X-ray Radiation
نویسندگان
چکیده
-This paper presents a radiation study on the pinned photodiode (PPD) and Transfer Gate (TG) of 4T (4 Transistor) CMOS Image Sensors (CIS). The PPD and the TG are the most sensitive elements for the sensor’s dark signal. The transfer gate length has an effect on the dark current due to the electric field variation in the transfer channel and the defect generation near the overlap region between PPD and TG. The low value of the TG clock signal is also evaluated for its influence on the dark signal. Meanwhile, the dimensional effect of the PPD and TG before and after radiation is demonstrated as well, which shows different results from 3T pixel.
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