US Patent 7651908 Methods of fabricating image sensors

A method of fabricating an image sensor which reduces fabricating costs through simultaneous formation of capacitor structures and contact structures may be provided. The method may include forming a lower electrode on a substrate, forming an interlayer insulating film on the substrate, the interlayer insulating film may have a capacitor hole to expose a first portion of the lower electrode. The method may further include forming a dielectric film on at least the first portion of the lower electrode, forming a first contact hole in the interlayer insulating film to expose a second portion of the lower electrode, forming a first conductive layer in at least the first contact hole and the capacitor hole, forming a second conductive layer on the first conductive layer to fill and cover the capacitor hole and the first contact hole, and planarizing the second conductive layer to simultaneously form a capacitor plug in the capacitor hole, a first contact plug in the first contact hole, an upper electrode beneath the capacitor plug, and a first contact barrier film beneath the first contact plug.