Conformal 3D Nanopatterning by Block Copolymer Lithography with Vapor-Phase Deposited Neutral Adlayer

Block copolymer (BCP) lithography is an effective nanopatterning methodology exploiting nanoscale self-assembled periodic patterns in BCP thin films. This approach has a critical limitation for nonplanar substrate geometry arising from the reflow and modification of BCP films and upon thermal or solvent annealing process, which is inevitable to induce the mobility of BCP chains for self-assembly process. Herein, reflow-free, 3D BCP nanopatterning is demonstrated by introducing a conformally grown adlayer by initiated chemical vapor deposition (iCVD) process. A highly crosslinked poly(divinylbenzene) layer was deposited directly onto BCP thin film surface by iCVD, which effectively prevented the reflow of BCP thin film during an annealing process. BCP nanopatterns could be stabilized on various substrate geometry, including nonplanar deformed polymer substrate, pyramid shape substrate, and graphene fiber surface. Fiber-type hydrogen evolution reaction (HER) catalyst is suggested by stabilizing lamellar Pt ...