Single-Photon Resolution CMOS Integrating Image Sensors

A CMOS image sensor realized in a commercially available 0.18 mu m CIS technology for near "single-photon detection" applications is presented. The pixel array features 1.2e- readout noise and 2.5e- overall noise comprising dark current shot noise effects at 60 frames per second (16 mu s row-time). The 1 x 11 mu m pixel (fill factor of 63%) provides a pixel conversion gain of 50 mu V/e-. High-dynamic range of over 150dB is achieved. Further research on noise in charge detector circuits has resulted in the invention of a novel ultra-low-noise pixel featuring in-pixel amplification enabling single-electron resolution imaging. A typical sense node referred readout noise of 0.9e- and an overall sense node referred noise floor of 1.5e- are measured at a pixel conversion gain of 300 mu V/e-.