Atomically Flat, 2D Edge Directed Self-Assembly of Block Copolymers.

Nanoscale shape engineering is an essential requirement for the practical use of two-dimensional (2D) materials, aiming at precisely customizing optimal structures and properties. Herein, sub-10-nm scale block copolymer (BCP) self-assembled nanopatterns finely aligned along the atomic edge of 2D flakes, including graphene, MoS 2 , and h-BN, are exploited for reliable nanopatterning of 2D materials. The underlying mechanism for the alignment of the self-assembled nanodomains was elucidated based on the wetting layer alternation of the BCP film in the presence of intermediate 2D flakes. The resultant highly aligned nanocylinder templates with remarkably low levels of line edge roughness (LER) and line-width roughness (LWR) yield a sub-10-nm wide graphene nanoribbon (GNR) array with noticeable switching characteristics (on-to-off ratio up to ∼ 6 × 10 4 ). This article is protected by copyright. All rights reserved.