Richard Leach - Fundamental prinsiples of engineering nanometrology (778895), страница 6
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It isasserted that what the MNT industry needs is a standards infrastructurethat will allow fabrication plants to interchange parts, packaging anddesign rules; effectively the MNT equivalent of macro-scale nuts and boltsor house bricks. This will not stifle innovation; on the contrary, it willallow designers and inventors to have more time to consider the innovativeaspects of their work, rather than having to waste time ‘re-inventing thewheel’.The results of recent government reviews [3] and surveys in Europe [4]and the USA [5] clearly indicate that standardization is the major issue thatis hampering commercial success of the MST industry. This book considersa subset of the metrology that will be required in the near future to supporta standards infrastructure for MNT. If interchangeability of parts is tobecome a reality, then fabrication plants need to move away from ‘in-house’or ‘gold’ standards, and move towards measurement standards andFundamental Principles of Engineering NanometrologyCopyright Ó 2010 by Elsevier Inc.
All rights reserved.CONTENTSWhat is engineeringnanometrology?The contents of thisbookReferences12C H A P T ER 1 : Introduction to metrology for micro- and nanotechnologytechniques that are traceable to national or international realisations of themeasurement units [6].Progress in MNT is not just of interest at the academic level. There isa considerable advantage in being able to reach a sufficient number of marketswith new devices and materials to be able to recover development costs. Thereis consequently much effort devoted not only to development of MNT devicesand materials, but also to maximising market uptake and transfer of technology from the research stage, through production, out to the commercialmarketplace.
In many cases, examination of the barriers preventing successfuluptake of new technology reveals some areas of metrology where there needsto be more research than is carried out at the moment. Also, metrology doesnot just allow control of production but can allow legal, ethical and safetyissues [7] to be settled in a quantitative and informative manner.There is a major thrust in standardization for MNT activities in manynational and regional committees.
The International Organization forStandardization (ISO) has recently set up ISO technical committee (TC) 229.The IEC has also established TC 113 to complement electrical activities.Recognising that there is an intersection between matter and radiation at theMNT level, several of the working groups are collaborations between ISO andIEC.
The Joint Working Groups (JWGs) are divided into terminology andnomenclature (JWG1), measurement and characterization (JWG2) and twosole ISO WGs on health, safety and environment (WG3) and product specifications and performance (WG4). The main work of the committees so farhas been to define common definitions for nanotechnology and to issuereviews of handling engineered nanomaterials in the workplace. Measurement and characterization standards are currently being developed especiallyfor carbon nanotube analysis. This work is also being complemented byactivities in Europe that are coordinated by CEN TC 352. There are alsomany well-established and related ISO committees that are not exclusivelyMNT but cover aspects of engineering nanometrology; for example, ISO TC213, which covers surface texture standards, and ISO TC 201, which coversmany of the standardization issues for scanning probe microscopes, and ISOTC 209 (cleanroom technologies) is also forming a working group (WG10) onnanotechnology considerations.1.1 What is engineering nanometrology?The field of engineering metrology relates to the measurement and standardization requirements for manufacturing.
In the past, engineeringmetrology mainly covered dimensional metrology, i.e. the science andThe contents of this booktechnology of length measurement (see [8,9]). Modern engineering metrologyusually encompasses dimensional plus mass and related quantity metrology.Some authors have also incorporated materials metrology into the fold [10]and this is an important inclusion. However, this book will concentrate onthe more traditional dimensional and mass areas. This choice is partly tokeep the scope of the book at a manageable level and partly because those arethe areas of research that the author has been active in.So, engineering nanometrology is traditional engineering metrology at theMNTscale.
Note that whilst nanotechnology is the science and technology ofstructures varying in size from around 0.1 nm to 100 nm, nanometrologydoes not only cover this size range. Nanometrology relates to measurementswith accuracies or uncertainties in this size range (and smaller!). Forexample, one may be measuring the form of a 1 m telescope mirror segmentto an accuracy of 10 nm.It is important to realise that there are many areas of MNT measurementthat are equally as important as dimensional and mass measurements. Otherareas not included in this book are measurements of electrical, chemical andbiological quantities, and the wealth of measurements for material properties, including the properties of particles. There are also areas of metrologythat could well be considered engineering nanometrology but have not beencovered by this book. These include the measurement of roundness [11], thinfilms (primarily thickness) [12,13], the dynamic measurement of vibratingstructures [14] and tomography measurements (primarily x-ray computedtomography [15] and optical coherence tomography [16]).
Once again, thechoice of contents has been dubiously justified above!1.2 The contents of this bookThis book is divided into ten chapters. Chapter 2 gives an introduction tomeasurement, including short histories of, and the current unit definitionsfor, length, angle, mass and force. Basic metrological terminology is introduced, including the highly important topic of measurement uncertainty.The laser is presented in chapter 2, as it is a very significant element of manyof the instruments described in this book.Chapter 3 reviews the most important concepts needed when designingor analysing precision instruments.
Chapter 4 covers the measurement oflength using optical interferometry, and discusses the concepts behindinterferometry, including many error sources. Chapter 5 reviews the area ofdisplacement measurement and presents most modern forms of displacement sensor. The field of surface texture measurement is covered in the next34C H A P T ER 1 : Introduction to metrology for micro- and nanotechnologythree chapters, as it is a very large and significant topic. Chapter 6 coversstylus and optical surface measuring instruments, and chapter 7 coversscanning probe and particle beam instruments. Both chapters 6 and 7 includeinstrument descriptions, limitations and calibration methods. Chapter 8presents methods for characterizing surfaces, including both profile and arealtechniques. Chapter 9 introduces the area of coordinate metrology andreviews the latest developments with micro-coordinate measuring machines.Lastly, chapter 10 presents a review of the latest advances in low mass andforce metrology.1.3 References[1] Storrs Hall J 2005 Nanofuture: what’s next for nanotechnology (PromethiusBooks)[2] Mulhall D 2002 Our molecular future: how nanotechnology, robotics,genetics and artificial intelligence will transform our future (PromethiusBooks)[3] 2004 Nanoscience and nanotechnologies: opportunities and uncertainties(Royal Society and Royal Academy of Engineering)[4] Singleton L, Leach R K, Cui Z 2003 Analysis of the MEMSTAND survey onstandardisation for microsystems technology Proc.
Int. Seminar MEMSTAND, Barcelona, Spain, 24-26 Feb. 11–31[5] MEMS Industry Group Report: ‘‘Focus on Fabrication,’’ Feb. 2003[6] Postek M T, Lyons K 2007 Instrumentation, metrology and standards:key elements for the future of nanotechnology Proc. SPIE 6648 664802[7] Hunt G, Mehta M 2008 Nanotechnology: risk, ethics and law (EarthscanLtd)[8] Hume K J 1967 Engineering metrology (Macdonald & Co.) 2nd edition[9] Thomas G G 1974 Engineering metrology (Newnes-Butterworth: London)[10] Anthony D M 1986 Engineering metrology (materials engineering practice)(Pergamon)[11] Smith G T 2002 Industrial metrology: surfaces and roundness (Springer)[12] Tompkins H G, Eugene A I 2004 Handbook of ellipsometry (Springer)[13] Yacoot A, Leach R K 2007 Review of x-ray and optical thin film measurementmethods and transfer artefacts NPL Report DEPC-EM 13[14] Lobontiu N 2007 Dynamics of microelectromechanical systems (Springer)[15] Withers P J 2007 X-ray nanotomography Materials Today 10 26–34[16] Brezinski M E 2006 Optical coherence tomography: principles and applications (Academic Press)CHAPTER 2Some basics of measurement2.1 Introduction to measurementOver the last couple of thousand years significant advances in technology canbe traced to improved measurements.
Whether we are admiring the engineering feat represented by the Egyptian pyramids, or the fact that in thetwentieth century humans walked on the moon, we should appreciate thatthis progress is due in no small part to the evolution of measurement.
It issobering to realise that tens of thousands of people were involved in bothoperations and that these people were working in many different placesproducing various components that had to be brought together – a large partof the technology that enabled this was the measurement techniques andstandards that were used [1].The Egyptians used a royal cubit as the standard of length measurement(it was the distance from Pharaoh’s elbow to his fingertips – see Figure 2.1),while the Apollo space programme ultimately relied on the definition of themetre in terms of the wavelength of krypton 86 radiation.In Egypt the standards were kept in temples and the priests werebeheaded if they were not recalibrated on time.
Nowadays there areworldwide systems of accrediting laboratories, and laboratories are threatened with losing their accreditation if the working standards are not recalibrated on time. Primary standards are kept in national measurementinstitutes that have a great deal of status and national pride.