Method of forming a nanowire and method of manufacturing a semiconductor device using the same

A method of manufacturing a semiconductor device, comprising:

• forming a trench by partially etching a semiconductor substrate;
• forming a first insulation layer pattern on the semiconductor substrate to fill up the trench, wherein the first insulation layer pattern covers a source/drain formation region of the semiconductor substrate, and the first insulation layer pattern covers a nanowire formation region of the semiconductor substrate connected to the source/drain formation region;
• forming an opening by etching an exposed portion of the semiconductor substrate by the first insulation layer pattern using the first insulation layer pattern as an etching mask;
• forming a spacer on sidewalls of the opening and the first insulation layer pattern;
• forming the nanowire connected to the source/drain formation region by anisotropically etching a portion of the semiconductor substrate exposed by the opening until a portion of the first insulation layer pattern formed in the trench is exposed;
• forming a second insulation layer pattern by partially etching the first insulation layer pattern and fully etching the spacer until the nanowire is exposed;
• forming a gate insulation layer on the semiconductor substrate to cover the nanowire;
• and
• forming a gate electrode on the gate insulation layer to enclose the nanowire.