High dynamic range cmos image sensor pixel with reduced metal-insulator-metal lateral overflow integration capacitor lag

Abstract

A pixel circuit includes a photodiode configured to photogenerate image charge in response to incident light. A floating diffusion is coupled to receive the image charge from the photodiode. A transfer transistor is coupled between the photodiode and the floating diffusion to transfer the image charge from the photodiode to the floating diffusion. A reset transistor is coupled between a bias voltage source and the floating diffusion. The reset transistor is configured to be switched in response to a reset control signal. A lateral overflow integration capacitor (LOFIC) including an insulating region disposed between a first metal electrode and a second metal electrode is also included. The first metal electrode is coupled to a bias voltage source. The second metal electrode is coupled to the reset transistor and selectively coupled to the floating diffusion.