Impacts of random telegraph noise with various time constants and number of states in temporal noise of CMOS image sensors

Abstract

This paper describes the impacts of random telegraph noise (RTN) with various time constants and number of states to temporal noise characteristics of CMOS image sensors (CISs) based on a statistical measurement and analysis of a large number of MOSFETs. The obtained results suggest that from a trap located relatively away from the gate insulator/Si interface, the trapped carrier is emitted to the gate electrode side. Also, an evaluation of RTN using only root mean square values tends to underestimate the effect of RTN with large signal transition values and relatively long time constants or multiple states especially for movie capturing applications in low light environment. It is proposed that the signal transition values of RTN should be incorporated during the evaluation.