Direct growth of graphene-like film microstructure on charge pre-patterned SiO_2/Si substrate

摘要

For a wide range of practical applications of graphene-like films (GLFs), it is highly desirable to have a material with high uniformity and good electric characteristics. GLFs in this work are defined as graphene films with the crystallite size of several tens of nm. The structure of a CVD-grown GLF is typically disturbed by post-deposition procedures, including transfer and lithography. In this work we aim at the catalyst-free and lithography-free selective deposition procedure, which directly yields the desired GLF pattern on a dielectric substrate, by-passing transfer and lithography, the destructive steps of the manufacturing process. The catalyst-free deposition of graphene-like films can be strongly enhanced by the near-surface electric charge, and in this work we use this effect for selective growth of GLF microstructures. The charge pattern is created by irradiation of the substrate with an e-beam. We study experimental conditions for the selective deposition of GLF from ethanol vapor on SiO2/Si substrate. The e-beam exposure parameters are optimized based on Monte-Carlo simulations and the experimental study of the deposited films Raman spectroscopy and AFM. The electrical properties are studied by the selectively-grown Hall microstructure; it is shown that the film has highly promising characteristics for practical applications.