Inch-Scale High Throughput Metrology of Graphene and Patterned Graphene Oxide

Abstract Inch-Scale High Throughput Metrology of Graphene and Patterned Graphene Oxide by Dennis Pleskot Master of Science, Graduate Program in Materials Science and Engineering University of California, Riverside, June 2013 Dr. Cengiz Ozkan, ChairpersonIn order to fully utilize the unique properties of graphene, large-area sheets of the material must be produced. As the demand for large, continuous sheets of graphene increases, the need to quickly and effectively characterize such a material correspondingly increases. In tandem, the use of patterned graphene oxide in practical applications has also expanded at a rapid pace, leading to a greater need to characterize this material as well. In this study, fluorescence quenching microscopy was examined as a means of analyzing 4 in2 sheets of graphene and patterned graphene oxide in a fast and efficient manner. It was determined that fluorescence microscopy offers a number of advantages in imaging these materials over conventional techniques such as Raman spectroscopy, SEM, and TEM. Fluorescence microscopy proved to be a highly scalable technique that is able to image a graphitic material in substantially less time than would be possible in these other methods while still maintaining adequate resolution. Unlike SEM and TEM, fluorescence microscopy is also a non-destructive characterization technique, allowing the samples that were actually characterized to be used in practical applications. Additionally, a clear contrast between graphene oxide and pristine graphene could be observed. Analysis of the fluorescence contrast histogram shows that graphene oxide displays a unique intensity peak and can thus not only be distinguished from pristine graphene but also defects in the sample, the presence of multiple layers, and changes in the uniformity of the graphene surface. These observations and results demonstrate the expanding usefulness of fluorescence microscopy as a high-throughput characterization technique