| 摘要 |
PROBLEM TO BE SOLVED: To easily and properly form a contact hole in an imaging region wherein a photoelectric conversion, transistor, etc., exist in a mixed state, and to prevent the occurrence of a dark current. SOLUTION: The imaging device has such a structure that a side wall consisting of a triple-layered insulation film is formed in a gate of a MOS transistor. For an interlayer insulation film formed between the triple-layered insulation film and a flattening film in an upper layer, a plasma silicon nitride film having a small content of nitrogen is used. With the silicon nitride film as an etching stopper, first etching is conducted to form a contact hole to the silicon nitride film. Then, the etching conditions are changed and second etching for processing the silicon nitride film is conducted to form a hole in the silicon nitride film, triple-layered insulation film, and gate insulation film which have nearly the same thickness to complete the contact hole now reaching a gate electrode and a diffusion layer of the silicon substrate. COPYRIGHT: (C)2006,JPO&NCIPI
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