Patent attributes
When a multi-layer structure is formed by forming the interconnect trenches or via holes having different patterns in a plurality of insulating films, an anti-reflective film and an upper resist film are stacked in this order over an insulating interlayer, and the anti-reflective film is etched through the upper resist film used as a mask, wherein the anti-reflective film is etched while varying a value of at least one etching condition correlative to Δ(L2−L1), expressing dimensional shift of width L2 of opening of the recess formed in the insulating film, with respect to width L1 of opening of the upper resist film, so as to reduce the dimensional shift Δ(L2−L1) as the aperture ratio of the opening to be formed in the upper resist film increases, depending on the aperture ratio.
