CHEMOEPITAXY-BASED DIRECTED SELF ASSEMBLY PROCESS WITH TONE INVERSION FOR UNIDIRECTIONAL WIRING

摘要

After forming a material stack including, from bottom to top, a dielectric material layer, a transfer layer, a hard mask layer and a neutral layer over a substrate, the neutral layer and the hard mask layer is patterned to create trenches therein that correspond to areas where unnecessary lines generated by a self-assembly of a self-assembling material subsequently formed and/or unnecessary portions of such lines are present. The self-assembling material is applied over the top surfaces of the patterned neutral layer and the transfer layer to form a self-aligned lamellar structure including alternating first and second domains. The second domains are removed selective to the first domains to provide a directed self-assembly (DSA) pattern of the first domains. Portions of the first domains not intersecting the trenches can be transferred into the patterned hard mask layer, resulting in a composite pattern of a pattern of trenches and the DSA pattern.

主权项

1. A method of forming a semiconductor structure comprising:
forming a vertical stack of a patterned hard mask layer and a patterned neutral layer overlying the patterned hard mask layer over a transfer layer located over a substrate, wherein the patterned hard mask layer and the patterned neutral layer include a first pattern of trenches exposing portions of the transfer layer; applying a self-assembling material over the transfer layer and the patterned neutral layer; forming a self-assembled self-aligned structure of the self-assembling material across top surfaces of the transfer layer and the patterned neutral layer, the self-assembled self-aligned structure comprising alternating first domains and second domains composed of first and second components of the self-assembling material, respectively; forming a second pattern of the first domains by removing the second domains selective to the first domains; patterning the patterned neutral layer and the patterned hard mask layer by employing portions of the first domains not intersecting the trenches as an etch mask; patterning the transfer layer employing remaining portions of the patterned hard mask layer as an etch mask to provide a patterned transfer layer; and forming tone-inversion layer portions by filling the spaces between the patterned transfer layer with a tone-inversion material.