Patent ID: 7365018

Claim:
A method for fabricating a semiconductor device, comprising: transferring a pattern from an initial photomask to a first photoresist layer of a layered structure, the first photoresist layer having alternating unexposed portions of width F and exposed portions, the initial photomask having a feature of width at least F to expose at least one of the unexposed portions, thereby forming, in the first photoresist layer, a first pattern which includes a gap having a width of at least 3F, the gap extends between two adjacent unexposed portions of the first pattern of the first photoresist layer; transferring the first pattern to a first hard mask below the first photoresist layer, forming spaced apart portions in the first hard mask on opposing sides of the gap; removing remaining portions of the first photoresist layer; transferring a pattern from an additional photomask having a pattern of features of width at least F to a second photoresist layer which is added to the spaced apart portions of the first hard mask, thereby forming protective regions in the second photoresist layer on opposing sides of the gap, each protective region extending between at least two of the spaced apart portions in the first hard mask; and removing additional layers in the layered structure through openings, including the gap, in the first hard mask which are not protected by the protective regions.