The present disclosure provides a method for forming an integrated circuit (IC) structure. The method comprises providing a semiconductor structure including a substrate, a dielectric layer formed over the substrate, and a hard mask region formed over the dielectric layer; forming a first photoresist layer over the hard mask region; performing a first lithography exposure using a photomask to form a first latent pattern; forming a second photoresist layer over the hard mask region; and performing a second lithography exposure using the photomask to form a second latent pattern. The photomask includes a first mask feature and a second mask feature. The first latent pattern corresponds to the first mask feature, and the second latent pattern corresponds to the first mask feature and the second mask feature.