Patent ID: 9640399
Date: 2017-05-02
CPC Classifications: G03F,H01L

Claim:
1. A method of forming patterns, the method comprising: forming a guide pattern and first peripheral patterns over an underlying layer, the guide pattern defining first openings, the first peripheral patterns defining second openings; forming a block copolymer layer filling the first and second openings; annealing the block copolymer layer to provide blocking portions in the second openings and to form at least one first domain and a second domain in each of the first openings, wherein the second domain surrounds the first domain; selectively removing the first domain to form third openings; and etching the underlying layer using the blocking portions and the second domain as etch barrier to form fourth openings that extend from the third openings into the underlying layer, wherein each of the second openings has a width less than a minor axis width of each of the first openings.