1T Process-Compatible Active Pixel Sensor With Enhanced Light Intensity Response Range

In this work, we present a novel one-transistor active pixel sensor with enhanced strong light response based on a semi-floating gate (SFG) transistor. The proposed device employs a metal-oxide-semiconductor (MOS) capacitor to store photo-generated holes from backside illumination, resulting in a larger full well capacity and improved light absorption characteristics. Our results demonstrate that the device exhibits an exceptionally wide light intensity response range, from ${1}.{0}\times {10} ^{-{6}}$ mW/cm2 to ${1}.{0}\times {10} ^{{2}}$ mW/cm2, achieving a substantial readout current difference exceeding $0.1~\mu $ A. Furthermore, the low light response can be enhanced by more than 8 times by adjusting the operating voltage. Under standard 0.13- $\mu $ m node, the fill factor is also improved by 30% without increase in cost and tenfold reduction is achieved in power consumption simultaneously.