This technology uses graphene sheets and force transducers to calibrate nanotech instruments with improved accuracy and precision. The physical properties of graphene are ideal for this application because of the unique atomic structure of graphene. Calibration and standardization with graphene gives well-defined force-versus-displacement curves. Graphene is an extremely strong material and force calibration curves can be constructed with ease by altering the number of layers of graphene being measured. This technology may improve the function and accuracy of nanoscale measurement devices such as atomic force microscopes (AFM) and nanoindenters.
Graphene is an easily manufactured two-dimensional array of covalently bonded carbon atoms. The consistency and strength of its mechanical properties arises from its atomic arrangement: there are no grain boundaries and a sheet consists of a single crystal of material. This absence of defects gives graphene a very consistent Young's modulus and lets it produce well-behaved force-versus-displacement curves.
Glass fibers have been used in the past as calibration standards for AFM and nanoindenters but exhibit inconsistent elastic and mechanical properties because of defects in the atomic structure of glass. Graphene is an attractive alternative and provides improved results when calibrating nanotech instruments.
Jeffrey W. Kysar, Ph.D. James Hone, Ph.D.
Patent Issued (US 8,418,547)
Tech Ventures Reference: IR M09-013