A semiconductor device operable to demodulate incident modulated electromagnetic radiation, the semiconductor device comprising: a pinned photodiode structure including a substrate of a first type, an implant layer of a second type disposed within the substrate, first and second auxiliary implant layers of the second type disposed within the substrate and each disposed adjacent to the implant layer of the second type, an implant layer of the first type disposed within the implant layer of the second type and extending into the first and second auxiliary implant layers of the second type, an insulator disposed on a surface of the substrate, and a photo-detection region; first and second transfer gates disposed on a surface of the insulator, the transfer gates being operable to generate a field within the substrate; and first and second floating diffusion implant layers of the second type disposed within the substrate.