Manufacture of solid state imager having plurality of photosensors per each pixel

摘要

A second conductivity type well is formed in a first conductivity type semiconductor substrate. Vertical CCD channels of the first conductivity type are formed in the second conductivity type well. Vertical transfer electrodes are formed above the vertical CCD channels to form vertical CCDs along with the vertical CCD channels. A first impurity diffusion layer is formed in the well by implanting first conductivity type impurities along a first direction crossing the normal direction of the semiconductor substrate. A second impurity diffusion layer is formed in the well by implanting first conductivity type impurities along a second direction crossing the normal direction of the semiconductor substrate. A third impurity diffusion layer of the second conductivity type is formed between the first and second impurity diffusion layer. A fourth impurity diffusion layer of the second conductivity type is formed in the well above the first to third impurity diffusion layers.