Semiconductor device and manufacturing method thereof

摘要

The interval between gate electrodes in a memory cell portion and the interval between gate electrodes in a peripheral circuit portion are set so as to have a relation with the widths of sidewall insulating films of the gate electrodes. Using an etching stopper film, first only a memory cell contact hole is selectively formed and a silicon film is filled at the bottom. As a result, an optimum electrode structure can be each provided on an n type diffusion layer in the memory cell portion and an n type diffusion layer in the peripheral circuit portion.