Method of forming oriented block copolymer line patterns, block copolymer line patterns formed thereby, and their use to form patterned articles

A method of preparing a block copolymer film comprising a line pattern, comprising:

• forming a block copolymer film on a substrate surface comprising parallel facets;
• and
• annealing the block copolymer film to form an annealed block copolymer film comprising linear microdomains parallel to the substrate surface and orthogonal to the parallel facets;
• wherein the parallel facets of the substrate are characterized by a pitch λ;
• wherein the block copolymer in bulk comprises a hexagonal array of cylindrical microdomains characterized by a center-to-center spacing, L2, of adjacent cylindrical microdomains;
• and
• wherein λ/L2 is either less than or equal to 0.73 or greater than or equal to 1.4.