Patent ID: 7781344

Claim:
A method for manufacturing a semiconductor device, comprising the steps of: forming a hard mask layer and a first anti-reflective layer one by one over an etching target layer, the etching target layer including a dense pattern region and an isolation pattern region, wherein a pattern density of the dense pattern region is higher than the pattern density of the isolation pattern region; selectively etching the first anti-reflective layer to expose the hard mask layer in the isolation pattern region; forming a second anti-reflective layer over the first anti-reflective layer and the hard mask layer; forming a photoresist pattern on the second anti-reflective layer; and selectively etching the second anti-reflective layer, the first anti-reflective layer, and the hard mask layer, by using the photoresist pattern as an etching mask, thereby forming a hard mask pattern and over-etching the second anti-reflective layer in the isolation pattern region so that the hard mask pattern in the isolation pattern region is shrunk against the photoresist pattern in the isolation pattern region.