Charge Transfer Noise and Lag in CMOS Active Pixel Sensors
نویسنده
چکیده
This paper reports on the investigation of charge-transfer noise and lag in CMOS image sensors. Noise and lag are analyzed for buried-photodiode CMOS active-pixel-sensor (APS) devices using a simple Monte-Carlo technique. Since the main mechanism of charge-transfer noise involves carrier emission over a barrier, the results are applicable to the soft reset of photodiode-type CMOS APS devices, and charge transfer from a singlepoly-photogate-type CMOS APS with a bridging diffusion. Whereas the literature and conventional wisdom has focused on either (kTC) or (kTC/2) like behavior, the noise is found to behave like shot noise for both small and large signals.
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