A method for inducing nonuniform strain in graphene films is developed. Pillars made of a dielectric material (electron beam resist) are placed between graphene and the substrate, and graphene sections between pillars are attached to the substrate. The strength and spatial pattern of the strain can be controlled by the size and separation of the pillars. Application of strain is confirmed by Raman spectroscopy as well as from scanning electron microscopy (SEM) images. From SEM images, the maximum stretch of the graphene film reaches about 20%. This technique can be applied to the formation of band gaps in graphene.
@article{arxiv.1106.1507,
title = {Introducing Nonuniform Strain to Graphene Using Dielectric Nanopillars},
author = {Hikari Tomori and Akinobu Kanda and Hidenori Goto and Youiti Ootuka and Kazuhito Tsukagoshi and Satoshi Moriyama and Eiichiro Watanabe and Daiju Tsuya},
journal= {arXiv preprint arXiv:1106.1507},
year = {2015}
}