Method of forming a fine pattern by using block copolymers

A method of forming a fine pattern, the method comprising:

• forming a phase separation guide layer on a substrate;
• forming a neutral layer on the phase separation guide layer;
• forming a first pattern on the neutral layer, the first pattern including a plurality of first openings;
• forming a second pattern including a plurality of second openings by changing the first pattern, each of the plurality of second openings having a smaller width than each of the plurality of first openings;
• forming a neutral pattern by etching an exposed portion of the neutral layer using the second pattern as an etch mask, the neutral pattern including a plurality of guide patterns exposing a portion of the phase separation guide layer;
• removing the second pattern to expose a top surface of the neutral pattern;
• forming a material layer on the neutral pattern and the phase separation guide layer exposed through the plurality of guide patterns, the material layer including a block copolymer;
• and
• forming a fine pattern layer on the neutral pattern and the phase separation guide layer, the fine pattern layer including a first block and a second block;
• wherein each of the plurality of second openings of the second pattern has a width that is equal to about half the width of any one of the first openings of the first pattern.