A semiconductor device includes a multiple insulation layer structure in which
multiple insulation layers each having interconnection layer are built up and either
one of the interconnection layer forming a fuse is blown in order to select a spare
cell to relieve a defective cell; and an opening area corresponding to said fuse,
the opening being formed on one or more insulation layers disposed above the layer
which includes the fuse, wherein a side wall position corresponding to the opening
of the first protective insulation film formed on the top layer of the multiple
layers and a side wall position corresponding to the opening of the second protective
insulation film formed on the first protective insulation film are continuous at
the boundary thereof.