an area with no fuse formed.
Next, a first interlayer insulation film covering the first conductive film pattern is formed on the insulation film and further a second conductive film pattern is formed on the first interlayer insulation film. The second conductive film pattern is constituted of the LSI wirings formed in the wiring region. Next, the second interlayer insulation film for covering the second conductive film pattern is formed on the first interlayer insulation film and further, a third conductive film pattern is formed on the second interlayer insulation film. The second conductive film pattern and the third conductive film pattern are formed of aluminum alloy.
After that, a protective film for covering the third conductive film pattern is formed on the second interlayer insulation film. The protective filmis formed of, for example, silicon nitride by CVD method.
After a resist layer is formed on the silicon nitride film by coating with a photo resist, resist pattern having an opening is formed in the resist layer in the fuse region by executing exposure and development to the resist layer.
Next, by dry etching with the resist pattern as a mask, the protective film in the fuse region, the second interlayer insulation film and the first interlayer insulation film are removed in order to form a fuse window. The stopper film is exposed on the bottom of the fuse window.
Next, the stopper film in the fuse region is removed by dry etching. By setting etching selectivity larger than 1 at this time, the stopper film in the fuse region