Patent attributes
A pixel group of an image sensor includes first through fourth unit pixels in a matrix form of two pixels rows and two pixel columns, and a common floating diffusion region in a semiconductor substrate at a center of the pixel group and shared by the first through fourth unit pixels. Each of the first through fourth unit pixels includes a photoelectric conversion element in the semiconductor substrate, and a pair of vertical transfer gates in the semiconductor substrate and extending in a vertical direction perpendicular to a surface of the semiconductor substrate. The pair of vertical transfer gates transfer photo charges collected by the photoelectric conversion element to the common floating diffusion region. Image quality is enhanced by increasing sensing sensitivity of the unit pixel through the shared structure of the floating diffusion region and the symmetric structure of the vertical transfer gates.
