Patent attributes
A semiconductor device comprises a first Cu interconnect layer, an interlayer insulation film formed thereon, a via hole formed in the interlayer insulation film to expose a part of the first Cu interconnect layer and a Cu via formed within the via hole and connected to the first Cu interconnect layer. A TaN barrier film and a Ta barrier film are laminated on the side surface of the Cu via, and only the Ta barrier film is formed under the bottom surface thereof. The adherence between the TaN barrier film and the interlayer insulation film is strong, and the adherence between the Ta barrier film and copper is strong. Both the barrier films prevent Cu contamination due to diffusion of Cu and at the same time, enhance adherence between Cu and the interlayer insulation film at the side surface of the Cu via to prevent removal of the Cu via.
