Patent ID: 6221686
Filing Date: 2001-04-24
Classification: H01L

Abstract:
A method of forming an image sensor comprising:providing a semiconductor substrate of a first conductivity type;forming an enhancement layer on the substrate, the enhancement layer having the first conductivity type and a first doping concentration;forming a first well on a first portion of the enhancement layer, the first well having the first conductivity type and a second doping concentration that is greater than the first doping concentration wherein the first well has a first depth into the enhancement layer;forming a conducting region of a second conductivity type in a second portion of the enhancement layer wherein a first portion of the conducting region forms a portion of a MOS transistor; andforming a pinned layer of the first conductivity type in the second region of the enhancement layer by forming a first portion of the pinned layer within the conducting region and a second portion of the pinned layer extending laterally from the conducting region in a direction away from the MOS transistor.