A photosensitive device is disclosed which comprises a semiconductor substrate, at least one reverse biased device, such as a P-N junction diode formed in the semiconductor substrate, and at least one photosensitive layer disposed above the semiconductor substrate and substantially covering the reverse biased device, the photosensitive layer releasing electrons and holes when struck by photons, wherein the photon generated electrons and holes in the photosensitive layer reach the reverse biased device and create a combination current therein when a light shines thereon.