摘要 |
On a substrate, a first insulating film, a first interlayer insulating film, a second and third insulating films, and a second interlayer insulating film are formed. Wire trenches are formed reaching the upper surface of the third insulating film, and via holes are formed from the bottom of the wire trench to the upper surface of the first insulating film. Formation of the wire trench is performed by etching the second interlayer insulating film under a condition in which the second interlayer insulating film is selectively etched. The third insulating film exposed at the bottoms of the wire trenches and the first insulating film exposed at the bottoms of the via holes are removed by etching under a condition in which the third insulating film is selectively etched. Wires are filled in the via holes and the wire trenches. <IMAGE> |