An image sensor structure includes a plurality of pixels formed on a substrate. Each pixel includes an image senor interconnect structure, a separator layer and an electrode layer, wherein the separator layer has a first thickness an a sidewall of the separator layer is recessed from a sidewall of the electrode layer. A first doped amorphous silicon layer id formed on the electrode layer, wherein the separator layer and the first doped amorphous silicon layer of a pixel are disconnected from that of an adjacent pixel.