Sub-10-nm patterning via directed self-assembly of block copolymer films with a vapour-phase deposited topcoat
Source abstract
Abstract
Directed self-assembly (DSA) of the domain structure in block copolymer (BCP) thin films is a promising approach for sub-10-nm surface patterning. DSA requires the control of interfacial properties on both interfaces of a BCP film to induce the formation of domains that traverse the entire film with a perpendicular orientation. Here we show a methodology to control the interfacial properties of BCP films that uses a polymer topcoat deposited by initiated chemical vapour deposition (iCVD). The iCVD topcoat forms a crosslinked network that grafts to and immobilizes BCP chains to create an interface that is equally attractive to both blocks of the underlying copolymer. The topcoat, in conjunction with a chemically patterned substrate, directs the assembly of the grating structures in BCP films with a half-pitch dimension of 9.3 nm. As the iCVD topcoat can be as thin as 7 nm, it is amenable to pattern transfer without removal. The ease of vapour-phase deposition, applicability to high-resolution BCP systems and integration with pattern-transfer schemes are attractive properties of iCVD topcoats for industrial applications.
Source: europepmc · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Block Copolymer Self-Assembly · Fluid Dynamics and Thin Films · Advancements in Photolithography Techniques
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (46)
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