Methods and compositions for providing spaced lithography features on a substrate by self-assembly of block copolymers

摘要

A method is disclosed to form a row of mutually spaced elongate lithography features along an axis on a substrate, for instance for use as contact electrodes for a NAND device. The method involves directing alignment of self-assemblable block copolymer (BCP) composition in a trench in a resist layer on the substrate, having the substrate as base, with an epitaxy feature in the trench to cause the ordered BCP layer to have elongate domains stretching across the trench width, substantially parallel to each other and to the substrate. The ordered BCP layer is then used as a resist to pattern the substrate. A BCP composition adapted to assemble with spaced discontinuous elongate elliptical domains is disclosed. The method may allow for sub-resolution contact arrays to be formed using UV lithography.

主权项

1. A method of forming a row of mutually spaced elongate lithography features along a substrate axis on a substrate, the method comprising:
providing a ordered layer of self-assemblable block copolymer composition on the substrate by:
causing a self-assemblable block copolymer composition in a trench to self-assemble to give an ordered layer of self-assembled block copolymer composition in the trench, the trench being through a resist layer on the substrate, over the substrate axis, aligned with its length lying substantially parallel to the substrate axis and having a side-wall of resist and a base of substrate bared of resist,wherein the block copolymer composition is adapted to form an ordered layer comprising first elongate domains, defining long axes substantially parallel to their greatest widths, self-assembled side-by-side on the substrate, alternating with a second domain therebetween, wherein the long axes of the elongate domains lie substantially parallel to each other, and substantially parallel to the substrate,wherein an epitaxial feature is provided in the trench to direct self-assembly of the block copolymer composition such that the long axes of the elongate domains lie substantially normal to the substrate axis, andusing the ordered layer of self-assembled block copolymer composition as a further resist layer to provide the mutually spaced elongate lithography features on the substrate.