| 摘要 |
The via contact structure is rendered into a dual damascene type via contact structure having a wide groove and a via contact hole lying below the wide groove, and the interior of the lower via contact hole is filled up with a filling material composed of tungsten, while, the interior of the upper groove is filled up with aluminum. Since the interior of the lower via contact hole is thus filled up with a filling material comprising tungsten, aluminum which has a low reflowability may be used only in the upper groove. As for the filling material for filling up the wide groove, the wide groove can be filled up sufficiently well even with aluminum which is not high in reflowability. By combining the filling of the via contact hole with tungsten and the filling of the groove with aluminum as mentioned above, a via contact filling with a high aspect ratio can be realized. Further, the problem or drawback that, at the time of forming the second metal wiring layer, the first metal wiring layer may be melted due to the high-temperature heat treatment performed for depositing the metal material is eliminated, and thus, it becomes possible to realize a dual damascene type via contact structure which can be applied to a multi-layer wiring structure.
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