Creating periodic local strain in monolayer graphene with nanopillars patterned by self-assembled block copolymer

A simple and viable method was developed to produce biaxial strain in monolayer graphene on an array of SiO2 nanopillars. The array of SiO2 nanopillars (1 cm2 in area, 80 nm in height, and 40 nm in pitch) was fabricated by employing self-assembled block copolymer through simple dry etching and deposition processes. According to high resolution micro-Raman spectroscopy and atomic force microscopy analyses, 0.9% of maximum biaxial tensile strain and 0.17% of averaged biaxial tensile strain in graphene were created. This technique provides a simple and viable method to form biaxial tensile strain in graphene and offers a practical platform for future studies in graphene strain engineering.