The Challenge to Develop Metrology at the Nanoscale
Since nanotechnology goods are manufactured and utilised by the community, legal metrology, human safety, and the environment demand traceable measurement techniques. This is the business of the international network of measurements called metrology. Afte
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The Challenge to Develop Metrology at the Nanoscale R. Ince
Abstract Since nanotechnology goods are manufactured and utilised by the community, legal metrology, human safety, and the environment demand traceable measurement techniques. This is the business of the international network of measurements called metrology. After 2017 the realisation of the international metre will be through the lattice parameter of silicon or another suitable crystalline material. Many NMI’s have developed traceable instrumentation systems primarily for AFM, but only partly for SEM and optical instrumentation. None of the existing techniques is able to meet the present requirements for reliable metrology of nanomaterials. However suitable reference materials are being developed alongside standardised sample preparation methods. Present second generation nanostructures are complex requiring multiparameter and ensemble measurements that AFM or SEM cannot offer. Ensemble techniques reveal the sub-nanometre detail required in the healthcare and electronics industry. The next generation of manufacturing in these industries will be three-dimensional complex sub-nm architectures, and nanometrology is currently being driven there.
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Metrology
Metrology is the science of measurement; its mission and implementation is international and ensures that each of the seven international SI units [1] is reliable at all the levels shown in Fig. 4.1. This is achieved via traceability to the representation of each unit held in national laboratories through a chain of unbroken documented calibrations. Representation of each unit is the experiment that realises the unit in national standards laboratories. The national representations must therefore be traceable to the international values (some still held at the international R. Ince (&) Department of Physics, Yeditepe University, Kayisdagi Caddessi, Kadikoy, 34755 Istanbul, Turkey e-mail: [email protected] © Springer International Publishing Switzerland 2016 H. Ünlü et al. (eds.), Low-Dimensional and Nanostructured Materials and Devices, NanoScience and Technology, DOI 10.1007/978-3-319-25340-4_4
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Decreasing measurement accuracy BIPM
National standards
Primary standards
Working standards Research, industrial and community instruments Fig. 4.1 Traceability pyramid showing laboratory hierarchy. Absolute accuracy refers to how close a measurement is to a traceable standard held in the national standards laboratory
bureau of weights and measures, BIPM in Paris) by international comparisons which is described by an uncertainty (a value expressing how near to the real value the measurement is). This creates a highly correlated set of international base units. Scientists themselves are often unaware that such a vast network of perpetual calibrations exists at so many levels (traceability pyramid) and underscores all global measurements for science, trade, and research. Indeed the SI is just as important a part of the national infrastructure as roads, buildings and bridges; the tra
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