Pitch division using directed self-assembly

A method comprising:

• forming a target pattern of a target material on a surface of a substrate, the target pattern comprising a first pitch;
• depositing a directed self-assembly alignment promotion (DSAAP) layer tailored for one of two blocks of a block copolymer on the target material;
• depositing a block copolymer on the surface of the substrate, wherein one of two blocks of the block copolymer aligns to the target material and the two blocks self assemble after deposition into repeating lamellar bodies on the surface of the substrate with an orientation perpendicular to the substrate;
• selectively removing the one of the two blocks of the block copolymer without the affinity for the target material to leave the other as a polymer pattern with a second pitch that is less than the first pitch;
• and
• patterning the substrate with the polymer pattern.

A method comprising:

• forming a target pattern of a target material on a surface of a substrate, the target pattern comprising a first pitch;
• depositing a block copolymer on the surface of the substrate, wherein one of two blocks of the block copolymer aligns to the target material and the two blocks self assemble after deposition into repeating lamellar bodies with an orientation perpendicular to the substrate;
• selectively removing the one of the two blocks of the block copolymer to leave the other as a polymer pattern;
• depositing a sacrificial material complementary to the polymer pattern;
• removing the polymer pattern while leaving the sacrificial material as a complementary pattern on the substrate;
• etching openings in the substrate with the complementary pattern as a mask, the polymer pattern comprising a second pitch that is less than the first pitch;
• and
• forming interconnects in the openings.

An apparatus comprising:

• an integrated circuit substrate comprising a plurality of contact points and a dielectric layer on the contact points;
• a target pattern formed in a surface of the dielectric layer;
• and
• a self-assembled layer of repeating alternating bodies of a block copolymer, wherein one of two blocks of the block copolymer is preferentially aligned to the target pattern.