Method for Directed Self-Assembly and Pattern Curing

摘要

Techniques disclosed herein include methods for DSA patterning and curing of DSA patterns. Techniques include curing phase-separated block copolymers using vacuum ultraviolet (VUV) light exposure at wavelengths from about 100 nanometers to 170 nanometers. VUV light can be generated using a plasma process system and from energizing various VUV-generating process gasses. A VUV curing step is executed (fully or partially) prior to executing an etch process to etch away one of the block copolymers. Such VUV exposure can selectively harden one block copolymer while weakening another block copolymer. This hardening and weakening increases etch selectivity enabling more effective etching and results in better patterns.

主权项

1. A method of processing a substrate, the method comprising:
positioning a substrate on a substrate holder of a plasma processing system, the substrate having a micro phase-separated pattern of block copolymers formed by directed self-assembly (DSA); flowing a first process gas into a plasma processing chamber of the plasma processing system, the first process gas being a gas that generates vacuum ultra violet radiation in a plasma state; irradiating the substrate with vacuum ultra violet radiation originating from plasma generated using the first process gas such that a first block copolymer increases in hardness and a second block copolymer decreases in hardness as compared to respective hardness values prior to exposure to vacuum ultra violet radiation; flowing a second process gas into the plasma processing chamber, the second process gas being a gas that generates etchants in a plasma state; and executing an etch process that exposes the substrate to plasma products generated from the second process gas such that at least a portion of the second block copolymer is etched and removed from the substrate.