摘要 |
A method for forming metal interconnects. A substrate having a metal line is provided. A dielectric layer with an opening exposing the metal line is formed over the substrate, which dielectric layer further comprises an etching stop layer. After forming a covering layer conformal to a profile of the opening over the substrate, a portion of the covering layer in a bottom of the opening is removed to expose the metal line. A conformal barrier layer and a metal layer are formed sequentially in the opening and the metal layer fills up the opening. After forming a cap layer covering the substrate, the cap layer and the dielectric layer are defined to form a second opening. Next, remove the dielectric layer exposed by the opening, thus forming air-gaps.
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