1. Field of the Invention
The present invention relates to a semiconductor device having an interconnection connected to a conductive layer present above a semiconductor substrate as well as to a manufacturing method thereof.
2. Description of the Background Art
Conventionally, a method of manufacturing a semiconductor device including the step of forming a hole penetrating a second interlayer insulating film covering a conductive layer formed on a first interlayer insulating film and reaching the conductive layer has been employed. In the method of manufacturing a semiconductor device, if a position at which the hole is formed is displaced from a position of the conductive layer, the hole reaches the first interlayer insulating film under the conductive layer. Such penetration caused by misalignment of the hole is more likely in a recent semiconductor device that has been reduced in size.
As a technique to prevent the hole from penetrating as far as the first insulating film under the conductive layer due to misalignment of the hole as described above, Japanese Patent Laying-Open No. 05-299515 discloses a technique to provide an etching stopper film solely on a sidewall of the conductive layer. In addition, Japanese Patent Laying-Open No. 2000-294631 discloses a technique to provide double etching stopper film in a damascene structure. Moreover, Japanese Patent Laying-Open No. 09-007970 discloses a technique to provide an etching stopper film only on a lower side of the conductive layer.
None of the techniques described above, however, can completely solve the problem of the hole reaching the first interlayer insulating film.
USPTO Backgrounds
USPTO Backgrounds