Method for manufacturing a non-volatile semiconductor memory device having contact plug formed on silicided source/drain region

摘要

A method for manufacturing a semiconductor device includes the steps of forming a flash memory cell provided with a floating gate, an intermediate insulating film, and a control gate, forming first and second impurity diffusion regions, thermally oxidizing surfaces of a silicon substrate and the floating gate, etching a tunnel insulating film in a partial region through a window of a resist pattern; forming a metal silicide layer on the first impurity diffusion region in the partial region, forming an interlayer insulating film covering the flash memory cell, and forming, in a first hole of the interlayer insulating film, a conductive plug connected to the metal silicide layer.