Anhydride copolymer top coats for orientation control of thin film block copolymers

摘要

The use of self-assembled block copolymer structures to produce advanced lithographic patterns relies on control of the orientation of these structures in thin films. In particular, orientation of cylinders and lamellae perpendicular to the plane of the block copolymer film is required for most applications. The preferred method to achieve orientation is by heating. The present invention involves the use of polarity-switching top coats to control block copolymer thin film orientation by heating. The top coats can be spin coated onto block copolymer thin films from polar casting solvents and they change composition upon thermal annealing to become “neutral”. Top coats allow for the facile orientation control of block copolymers which would otherwise not be possible by heating alone.

主权项

1. A method, comprising:
a. providing a substrate having a surface, a surface neutralization layer, a block copolymer, and a top coat; b. treating said substrate surface with said surface neutralization layer under conditions such that a first layer is created; c. coating said surface neutralization layer with block copolymer under conditions such that a second layer on said surface is created comprising a block copolymer film, and d. coating said block copolymer with a top coat so as to create a third layer on said surface, wherein said third layer controls the orientation of the block copolymer domains perpendicular to the plane of the film by thermal annealing alone.