Abstract: Pixel image sensors with lateral photodiode elements and vertical overflow drain systems. According to at least one embodiment of the present invention, an image sensor pixel includes a lateral photodiode element and a vertical overflow drain system for draining excessive charges accumulated in the charge collecting region of the lateral photodiode element and for resetting the charge collecting region of the lateral photodiode element.

Abstract: An image sensor element includes a vertical overflow drain structure to eliminate substrate charge diffusion causing CMOS image sensor noise. An extra chemical mechanical polish step used to shorten the micro-lens to silicon surface distance in order to reduce optical cross talking. One embodiment uses N type substrate material with P? epitaxial layer to form a vertical overflow drain. Deep P well implantation is introduced to the standard CMOS process to prevent latch-up between an N well to an N type substrate. A photo diode is realized by stacked N well/Deep N well and stacked P well/Deep P well to improve performance.