Patent attributes
A method for forming a semiconductor device is disclosed. A substrate comprising a structural layer thereon is provided. A hard mask layer is formed on the structural layer. A photoresist layer is formed on the hard mask layer. The photoresist layer is patterned to from a plurality of main photoresist patterns and at least one dummy photoresist pattern between the main photoresist patterns or adjacent to one of the main photoresist patterns, wherein width of the dummy photoresist pattern is less than that of the main photoresist patterns. Two main photoresist patterns are separated with each other by a first opening, and two dummy photoresist patterns are separated with each other by a second opening. Width of the second opening is less than that of the first opening. The hard mask layer is patterned using the patterned photoresist layer as a mask. The structural layer is patterned using the patterned hard mask layer as a mask.