US Patent 10497729 Image sensor having conductive layer and protective layer

An image sensor includes a substrate having a first region and a second region. The image sensor further includes a dielectric layer over the substrate. The image sensor further includes a conductive layer over the dielectric layer, wherein in the first region the conductive layer has a grid shape and in the second region a portion of the conductive layer is concave toward the substrate. The image sensor further includes a protective layer, wherein the protective layer is over the conductive layer in the first region, and over a top surface and along sidewalls of the conductive layer in the second region.