1、BS ISO 16700:2016Microbeam analysis Scanning electron microscopy Guidelines for calibratingimage magnificationBSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS ISO 16700:2016 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 1670
2、0:2016. It supersedes BS ISO 16700:2004 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee CII/9, Microbeam analysis.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to inc
3、lude all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2016 .Published by BSI Standards Limited 2016ISBN 978 0 580 89052 9 ICS 37.020 Compliance with a British Standard cannot confer immunity from legal obligations.This B
4、ritish Standard was published under the authority of the Standards Policy and Strategy Committee on 31 July 2016.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS ISO 16700:2016 ISO 2016Microbeam analysis Scanning electron microscopy Guidelines for calibrating image magnif
5、icationAnalyse par microfaisceaux Microscopie lectronique balayage Lignes directrices pour ltalonnage du grandissement dimageINTERNATIONAL STANDARDISO16700Second edition2016-08-01Reference numberISO 16700:2016(E)BS ISO 16700:2016ISO 16700:2016(E)ii ISO 2016 All rights reservedCOPYRIGHT PROTECTED DOC
6、UMENT ISO 2016, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written
7、 permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 16700:2016ISO
8、 16700:2016(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Terms and definitions . 14 Image magnification . 34.1 Scale marker 34.2 Expressing magnification 35 Reference material . 35.1 General . 35.2 Requirements for CRM . 45.3 Pitch patterns on CRM 45.4 Storage and handling . 46 Ca
9、libration procedures 56.1 General . 56.2 Mounting CRM . 56.3 Setting SEM operation conditions for calibration . 56.4 Image recording . 66.5 Measurement of image . 66.6 Calibration of magnification and scale marker . 76.6.1 General 76.6.2 Magnification 76.6.3 Scale marker 77 Accuracy of image magnifi
10、cation and scale marker 88 Calibration report . 98.1 General . 98.2 Contents of calibration report . 9Annex A (informative) Reference materials for magnification 11Annex B (informative) Parameters that influence the resultant magnification of an SEM .13Annex C (informative) Uncertainties in magnific
11、ation measurements .15Annex D (informative) Example of a test report 16Bibliography .18 ISO 2016 All rights reserved iiiContents PageBS ISO 16700:2016ISO 16700:2016(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member b
12、odies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental a
13、nd non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are d
14、escribed in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is draw
15、n to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on t
16、he ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment
17、, as well as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.The committee responsible for this document is ISO/TC 202, Microbeam analysis, Subcommittee SC 4, Scanning elec
18、tron microscopy (SEM).This second edition cancels and replaces the first edition (ISO 16700:2004), which has been technically revised.iv ISO 2016 All rights reservedBS ISO 16700:2016ISO 16700:2016(E)IntroductionThe scanning electron microscope is widely used to investigate the surface structure of a
19、 range of important materials such as semiconductors, metals, polymers, glass, food and biological materials, and this International Standard is relevant to the need for magnification calibration of the images. It describes the requirements for calibration of the image magnification in the scanning
20、electron microscope using a reference material or a certified reference material. ISO 2016 All rights reserved vBS ISO 16700:2016BS ISO 16700:2016Microbeam analysis Scanning electron microscopy Guidelines for calibrating image magnification1 ScopeThis International Standard specifies a method for ca
21、librating the magnification of images generated by a scanning electron microscope (SEM) using an appropriate reference material. This method is limited to magnifications determined by the available size range of structures in the calibrating reference material. This International Standard does not a
22、pply to the dedicated critical dimension measurement SEM.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest
23、 edition of the referenced document (including any amendments) applies.ISO/IEC 17025:2005, General requirements for the competence of testing and calibration laboratoriesISO Guide 30, Reference materials Selected terms and definitionsISO Guide 34, General requirements for the competence of reference
24、 material producersISO Guide 35, Reference materials General and statistical principles for certification3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1scanning electron microscopeSEMinstrument that produces magnified images of a specimen by sc
25、anning its surface with an electron beam3.2imagetwo-dimensional representation of the specimen surface generated by SEM (3.1)Note 1 to entry: A photograph of a specimen taken using an SEM is a good example of an image.3.3image magnificationratio of the linear dimension of the scan display to the cor
26、responding linear dimension of the specimen scan field3.4scale markerline/generated line (intervals) on the image (3.2) representing a designated actual length in the specimen3.5reference materialRMmaterial, sufficiently homogeneous and stable with respect to one or more specified properties, which
27、has been established to be fit for its intended use in a measurement processINTERNATIONAL STANDARD ISO 16700:2016(E) ISO 2016 All rights reserved 1BS ISO 16700:2016ISO 16700:2016(E)3.6certified reference materialCRMreference material (3.5) characterized by a metrologically valid procedure for one or
28、 more specified properties, accompanied by a certificate that provides the value of the specified property, its associated uncertainty, and a statement of metrological traceabilityNote 1 to entry: For the purposes of this International Standard, an RM/CRM possesses pitch pattern(s) with the desired
29、range of pitch size(s) and accuracy, to be used for the calibration of the image magnification (3.3).3.7calibrationset of operations which establish, under specified conditions, the relationship between the magnification indicated by the SEM (3.1) and the corresponding magnification determined by ex
30、amination of an RM (3.5) or a CRM (3.6)3.8tilt angleangle of the inclined specimen surface from the plane perpendicular to the electron beam axisNote 1 to entry: See Figure 1.Key1 tilted specimen2 electron beam3 specimen4 tilt angleFigure 1 Tilt angle3.9displayanalog or digital device used for visua
31、lization of images (3.2)Note 1 to entry: Examples of display are a cathode ray tube, plasma display panel, liquid crystal display, etc.3.10working distancedistance between the specimen surface and the bottom plane of the objective lens of the SEM (3.1)3.11pitchclosest separation of two similar featu
32、res on a specimen which are equivalent points on a repeat pattern2 ISO 2016 All rights reservedBS ISO 16700:2016ISO 16700:2016(E)3.12accuracycloseness of agreement between a test result and the accepted reference valueNote 1 to entry: A “test result” constitutes the observed values of a pitch (3.11)
33、 of a CRM (3.6) obtained by the procedure outlined in this International Standard.Note 2 to entry: The term “accepted reference value” is a value certified by a national or an international calibrating laboratory. There will be an uncertainty associated with this value which should also appear on th
34、e certificate.Note 3 to entry: Accuracy and precision are different. Precision is defined as the closeness of agreement between independent test results obtained under stipulated conditions. See ISO 5725-1.4 Image magnification4.1 Scale markerTo indicate magnification, superimpose on the image a sca
35、le marker and the corresponding length, in SI units, that it actually represents on the specimen. An example is shown in Figure 2.NOTE In Figure 2, the length indicated by the arrows corresponds to 500 nm after the calibration.Figure 2 Scale marker and its length4.2 Expressing magnificationMagnifica
36、tion of an image is given by a number representing the number of times the object has been magnified and it is accompanied by the symbol “” (e.g. 100 , 10 000 , 10k or 100, 10 000, 10k, where 100, 10 000 and 10k are magnitude numbers).NOTE 1 It is not always necessary to show the magnification when
37、the scale marker is shown on the image.NOTE 2 The magnification shown on the image corresponds to a chosen output device, which can be a display monitor or a printer or a photographing device. The scale marker shown on the image is independent from the output device chosen by the operator of the SEM
38、. The magnification shown corresponds to the scale marker only when the image is displayed or printed on the operator-chosen output device.5 Reference material5.1 GeneralSee ISO Guide 30.For calibrating the magnification of an image, wherever possible, choose a CRM that is produced in accordance wit
39、h ISO Guide 34 and certified in accordance with ISO Guide 35.When a suitable CRM is not available, an RM produced in accordance with ISO Guide 34 may be used. ISO 2016 All rights reserved 3BS ISO 16700:2016ISO 16700:2016(E)5.2 Requirements for CRMEnsure that the chosen CRM is stable with respect to
40、vacuum and repeated electron beam exposure, provides good contrast in the SEM image, is electrically conductive, can be cleaned to remove contamination occurring during normal use without causing mechanical damage or distortion, and has an associated valid calibration certificate.5.3 Pitch patterns
41、on CRMPitch patterns on the CRM may be in any one or more of the following forms: an orthogonal cross grid; a line array; a dot array; an orthogonal dot array.Ensure that the chosen CRM contains pitch patterns that allow for calibration in at least one direction, and that the uncertainty in the pitc
42、h patterns is consistent with the targeted accuracy.NOTE 1 There are cases where the CRM contains pitch patterns both in X and Y directions so that the measurements can be performed in orthogonal directions without the necessity of mechanically rotating the CRM. In some cases, the CRM additionally c
43、ontains other structures for testing image distortion and/or resolution.NOTE 2 There are instances where the chosen CRM has different-sized pitch patterns to cover the whole range of magnifications for which calibration is needed. It can also be necessary to have more than one CRM to cover the desir
44、ed range of magnifications.5.4 Storage and handlingStore the CRM in a desiccating cabinet or in a vacuum container.NOTE To ensure minimal handling of the actual CRM, it can be permanently mounted on a stub.Handle the CRM using fingerstalls, clean room gloves or tweezers.Visually inspect the CRM surf
45、ace for contamination and deterioration, as this may affect calibration. Do not use the CRM if it is damaged or grossly contaminated.Remove any dust, loose debris or other contamination from the CRM using clean dry air or nitrogen gas, taking care not to damage the CRM.Check the calibration of the C
46、RM at intervals by comparison with other CRMs; record the results. The frequency of verification may depend on the nature and usage of the CRM.Use the CRM for calibration purposes only.4 ISO 2016 All rights reservedBS ISO 16700:2016ISO 16700:2016(E)6 Calibration procedures6.1 GeneralParameters that
47、influence the resultant magnification of an SEM may cause systematic errors. These are listed in Annex B.The stability of the SEM will be a major factor in determining the calibration interval. Initially, it will be necessary to perform calibration at frequent intervals in order to verify that the S
48、EM is stable.The results obtained will provide an estimate of the reproducibility within the laboratory and the bias inherent in both the display and the data automatically superimposed on any output.The selection of the CRM depends on the magnification being used and accuracy required. For the purp
49、oses of this International Standard, ensure that the accuracy of calibration is better than 10 %.6.2 Mounting CRMAt the time of mounting the specimen, ensure that handling of the CRM is carried out in accordance with 5.4.Mount the CRM in accordance with the SEM and the CRM manufacturers instructions.Ascertain that there is a good electrical contact between the CRM and the specimen stage of the SEM.Check that the CRM is securely fixed on the specimen stage so that it does not move from its mounting. This enab
