A dual-pixel full color complementary metal oxide semiconductor (CMOS) imager is provided, along with an associated fabrication process. Two stand-alone pixels are used for three-color detection. The first pixel is a single photodiode, and the second pixel has two photodiodes built in a stacked structure. The two photodiode stack includes an n doped substrate, a bottom photodiode, and a top photodiode. The bottom photodiode has a bottom p doped layer overlying the substrate and a bottom n doped layer cathode overlying the bottom p doped layer. The top photodiode has a top p doped layer overlying the bottom n doped layer and a top n doped layer cathode overlying the top p doped layer. The single photodiode includes the n doped substrate, a p doped layer overlying the substrate, and an n doped layer cathode overlying the p doped layer.