Patent ID: 8309460

Claim:
A method of manufacturing a semiconductor device, comprising: forming a first material layer; forming a hard mask including a plurality of mask holes on the first material layer; forming a first sacrificial layer in the mask holes; removing the hard mask to form a plurality of sacrificial patterns including the first sacrificial layer; forming a second material layer on the sacrificial patterns; removing part of the second material layer to form a plurality of first sacrificial masks, each of the sacrificial patterns at least partially surrounded by a corresponding one of the first sacrificial masks; forming a second sacrificial layer on the first sacrificial masks, the second sacrificial layer formed to include voids; forming a third material layer in the voids; removing part of the third material layer to form a plurality of second sacrificial masks; and removing at least part of the sacrificial patterns, the second sacrificial layer, and the first material layer such that a plurality of first contact holes are formed between the first sacrificial masks and the second sacrificial masks, and a plurality of second contact holes are formed within the first sacrificial masks.