Nonvolatile semiconductor memory and method of fabrication thereof

A method of fabricating a nonvolatile semiconductor memory having a plurality of word lines and a plurality of bit lines intersecting the word lines, and memory cells at intersecting portions of the word lines and the bit lines, the method comprising:

• providing a semiconductor substrate having a first insulating film thereon and a polysilicon film on the first insulating film;
• patterning the polysilicon film to form floating gates of the memory cells and an etching stop layer;
• forming a second insulating film on the polysilicon film;
• forming a conductive film on the second insulating film;
• patterning the conductive film to form control gates of the memory cells and strip-shaped regions as the word lines, the word lines having a plurality of contact portions covered and surrounded by the etching stop layer in a plan view;
• accumulating an interlayer insulating film on the conductive film;
• and
• etching the interlayer insulating film, and opening contact holes for the contact portions above the conductive film.