Metallic coatings - Measurement of coating thickness - Scanning electron microscope method (ISO 9220:2022)

This document specifies a destructive method for the measurement of the local thickness of metallic and other inorganic coatings by examination of cross-sections with a scanning electron microscope (SEM). The method is applicable for thicknesses up to several millimetres, but for such thick coatings it is usually more practical to use a light microscope (see ISO 1463). The lower thickness limit depends on the achieved measurement uncertainty (see Clause 10).
NOTE       The method can also be used for organic layers when they are neither damaged by the preparation of the cross-section nor by the electron beam during imaging.

Metallische Überzüge - Messung der Schichtdicke - Verfahren mit Rasterelektronenmikroskop (ISO 9220:2022)

Dieses Dokument legt ein zerstörendes Verfahren zur Messung der örtlichen Schichtdicke metallischer und anderer anorganischer Überzüge fest, in dem Querschnitte mit einem Rasterelektronenmikroskop (REM) untersucht werden. Das Verfahren ist für Schichtdicken bis zu mehreren Millimetern anwendbar, allerdings ist es für solch dicke Schichten üblicherweise praktischer, ein Lichtmikroskop (siehe ISO 1463) zu verwenden. Die untere Dickengrenze hängt von der erreichten Messunsicherheit (siehe Abschnitt 10) ab.
ANMERKUNG Das Verfahren kann auch bei organischen Überzügen angewendet werden, wenn diese weder durch die Präparation des Querschnitts noch durch den Elektronenstrahl während der Bildgebung beschädigt werden.

Revêtements métalliques - Mesurage de l'épaisseur de revêtement - Méthode au microscope électronique à balayage (ISO 9220:2022)

Le présent document spécifie une méthode destructive pour le mesurage de l’épaisseur locale des revêtements métalliques et d’autres revêtements inorganiques par examen de coupes transversales au microscope électronique à balayage (MEB). Cette méthode s’applique aux épaisseurs pouvant atteindre plusieurs millimètres; toutefois, pour les revêtements d’une telle épaisseur, il est généralement plus pratique d’utiliser un microscope optique (voir l’ISO 1463). La limite inférieure de l’épaisseur dépend de l’incertitude de mesure obtenue (voir l’Article 10).
NOTE            Cette méthode peut également être utilisée pour les couches organiques lorsqu’elles ne sont endommagées ni par la préparation de la coupe transversale ni par le faisceau d’électrons pendant l’imagerie.

Kovinske prevleke - Merjenje debeline prevleke - Postopek z vrstičnim elektronskim mikroskopom (ISO 9220:2022)

Ta dokument določa porušitveno metodo za merjenje lokalne debeline kovinskih in drugih anorganskih prevlek s pregledom prečnih prerezov z vrstičnim elektronskim mikroskopom (SEM). Postopek se uporablja za debeline do nekaj milimetrov, vendar je za tako debele premaze uporaba svetlobnega mikroskopa običajno bolj praktična (glej standard ISO 1463). Spodnja mejna vrednost debeline je odvisna od dosežene merilne negotovosti (glej točko 10). OPOMBA: Postopek je mogoče uporabiti tudi za organske sloje, če se ne poškodujejo med pripravo prečnih prerezov oziroma jih ne poškoduje elektronski snop med slikanjem.

General Information

Status
Published
Public Enquiry End Date
24-May-2021
Publication Date
02-Mar-2022
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
02-Mar-2022
Due Date
07-May-2022
Completion Date
03-Mar-2022

Relations

Overview

EN ISO 9220:2022 - Metallic coatings: Scanning electron microscope method specifies a destructive technique for measuring the local thickness of metallic and other inorganic coatings by examination of prepared cross-sections using a scanning electron microscope (SEM). The method is applicable for coating thicknesses up to several millimetres (for very thick coatings, ISO 1463 / light-microscope methods are usually more practical). The lower usable thickness is governed by the achievable measurement uncertainty (see Clause 10). The standard also notes the method can be used for organic layers if they are not damaged by cross-section preparation or by the electron beam.

Key topics and technical requirements

  • Principle: Cut, mount, grind and polish a cross-section; capture a calibrated digital SEM image and perform thickness measurements using SEM software or external image-processing tools.
  • Instrumentation: Commercial SEMs and calibration tools for the SEM length-measurement function are required.
  • Calibration tools (examples from Clause 5.2):
    • Stage micrometre or graticule
    • Silicon wafer with certified regular pattern (metallic bumps)
    • Spherical polymer particles with certified diameters
    • Tools should have uncertainty < 5 %
  • Factors affecting measurement results (detailed in Clause 6):
    • Surface roughness, cross-section taper and specimen tilt
    • Coating deformation, edge rounding, smearing or etching artefacts
    • Presence of protective plating layers and poor contrast
    • Choice of magnification and SEM imaging parameters (explicitly linked to measurement uncertainty)
  • Preparation, calibration and procedure: Clauses 7–9 set out cross-section preparation, instrument calibration, image capture and measurement workflows.
  • Precision and reporting: Clause 10 (and informative Annex B) covers repeatability and reproducibility considerations and includes precision data from round-robin tests. Clause 11–12 specify how to express results and the required test-report content.

Applications and users

EN ISO 9220:2022 is intended for laboratories and professionals involved in:

  • Quality control and inspection of metallic coatings (plating, electrochemical and PVD/CVD coatings)
  • Failure analysis, metallography and surface-engineering investigations
  • Corrosion protection assessment where accurate local thickness data are needed Typical users: materials laboratories, metallurgists, coating suppliers, automotive/aerospace quality engineers, and research institutions.

Related standards

  • ISO 1463 - light-microscope method for thicker coatings (recommended when coatings are several millimetres thick)
  • Refer to Clause 10 and Annex B of EN ISO 9220:2022 for precision guidance and round‑robin data.

Keywords: EN ISO 9220:2022, coating thickness measurement, scanning electron microscope, SEM method, metallic coatings, calibration, cross‑section preparation, measurement uncertainty.

Standard
SIST EN ISO 9220:2022
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Standards Content (Sample)


SLOVENSKI STANDARD
01-april-2022
Nadomešča:
SIST EN ISO 9220:1999
Kovinske prevleke - Merjenje debeline prevleke - Postopek z vrstičnim
elektronskim mikroskopom (ISO 9220:2022)
Metallic coatings - Measurement of coating thickness - Scanning electron microscope
method (ISO 9220:2022)
Metallische Überzüge - Messung der Schichtdicke - Verfahren mit
Rasterelektronenmikroskop (ISO 9220:2022)
Revêtements métalliques - Mesurage de l'épaisseur de revêtement - Méthode au
microscope électronique à balayage (ISO 9220:2022)
Ta slovenski standard je istoveten z: EN ISO 9220:2022
ICS:
17.040.20 Lastnosti površin Properties of surfaces
25.220.40 Kovinske prevleke Metallic coatings
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 9220
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2022
EUROPÄISCHE NORM
ICS 25.220.40 Supersedes EN ISO 9220:1994
English Version
Metallic coatings - Measurement of coating thickness -
Scanning electron microscope method (ISO 9220:2022)
Revêtements métalliques - Mesurage de l'épaisseur de Metallische Überzüge - Messung der Schichtdicke -
revêtement - Méthode au microscope électronique à Verfahren mit Rasterelektronenmikroskop (ISO
balayage (ISO 9220:2022) 9220:2022)
This European Standard was approved by CEN on 19 February 2022.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2022 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 9220:2022 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 9220:2022) has been prepared by Technical Committee ISO/TC 107 "Metallic
and other inorganic coatings" in collaboration with Technical Committee CEN/TC 262 “Metallic and
other inorganic coatings, including for corrosion protection and corrosion testing of metals and alloys”
the secretariat of which is held by BSI.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by August 2022, and conflicting national standards shall
be withdrawn at the latest by August 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 9220:1994.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 9220:2022 has been approved by CEN as EN ISO 9220:2022 without any modification.

INTERNATIONAL ISO
STANDARD 9220
Second edition
2022-02
Metallic coatings — Measurement of
coating thickness — Scanning electron
microscope method
Revêtements métalliques — Mesurage de l'épaisseur de revêtement —
Méthode au microscope électronique à balayage
Reference number
ISO 9220:2022(E)
ISO 9220:2022(E)
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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 permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 9220:2022(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Instrumentation . 1
5.1 Scanning electron microscope . 1
5.2 Tools to calibrate the length measurement function of the SEM software . 1
6 Factors influencing the measurement results . 2
6.1 Surface roughness . 2
6.2 Taper of cross-section . 2
6.3 Specimen tilt . 2
6.4 Coating deformation . 2
6.5 Rounding of edges of the coating . 2
6.6 Plating a protection layer . 2
6.7 Etching . 2
6.8 Smearing . 3
6.9 Poor contrast . 3
6.10 Magnification . 3
6.11 SEM imaging parameters . 3
7 Preparation of cross-sections . 3
8 Calibration of instruments . 3
8.1 General . 3
8.2 Photography . 4
8.3 Measurement . 4
9 Procedure .4
10 Precision . 4
10.1 General . 4
10.2 Repeatability, r. 4
10.3 Reproducibility limit, R . 5
11 Expression of results . 5
12 Test report . 5
Annex A (informative) General guidance on the preparation and measurement of cross-
sections . 7
Annex B (informative) Details on precision .10
Bibliography .12
iii
ISO 9220:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). 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 and 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
described 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 drawn 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 the 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 of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 107, Metallic and other inorganic coatings,
in collaboration with the European Committee for Standardization (CEN) Technical Committee CEN/
TC 262, Metallic and other inorganic coatings, in accordance with the Agreement on technical cooperation
between ISO and CEN (Vienna Agreement).
This second edition cancels and replaces the first edition (ISO 9220:1988), which has been technically
revised.
The main changes are as follows:
— addition of two further calibration methods in 5.2, 8.2, and 8.3;
— deletion of technically outdated content concerning instability of SEMs and analogue photos or
concerning the operation of SEMs [removal of old Subclauses 6.11, 6.12, 6.13, 8.4, 9.2.1, 9.2.2, 9.3,
A.2.3, A.3.2, A.3.3, A.3.4, and A.3.7; revision of item e) in Clause 12];
— discussion of influences of imaging parameters on measurement uncertainty (new 6.11);
— revision of Clause 10 and addition of Annex B with precision data from round robin tests;
— revision of Annex A to (re-) align it with ISO 1463:2021;
— adding a bibliography with informative references.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
INTERNATIONAL STANDARD ISO 9220:2022(E)
Metallic coatings — Measurement of coating thickness —
Scanning electron microscope method
1 Scope
This document specifies a destructive method for the measurement of the local thickness of metallic
and other inorganic coatings by examination of cross-sections with a scanning electron microscope
(SEM). The method is applicable for thicknesses up to several millimetres, but for such thick coatings it
is usually more practical to use a light microscope (see ISO 1463). The lower thickness limit depends on
the achieved measurement uncertainty (see Clause 10).
NOTE The method can also be used for organic layers when they are neither damaged by the preparation of
the cross-section nor by the electron beam during imaging.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
local thickness
mean of the thickness measurements, of which a specified number is made within a reference area
[SOURCE: ISO 2064:1996, 3.4]
4 Principle
A test specimen is cut, ground, and polished from a cross-section of the coating for materialographic
examination by a scanning electron microscope. The measurement is made on the digital image
generated by the SEM using either the tools of the SEM’s operating software or by importing the image
file together with its calibration data into an image processing software and using that software’s tools.
5 Instrumentation
5.1 Scanning electron microscope
Suitable instruments are available commercially.
5.2 Tools to calibrate the length measurement function of the SEM software
Suitable tools are required for the calibration of the length measurement function of the SEM’s
software, e.g. a stage micrometre, or a graticule, or a piece from a silicon wafer with a regular pattern
of (cylindrical) metallic bumps with a certified distance of the cylinder axes, or spherical polymer
ISO 9220:2022(E)
particles of certified diameter in the range of a few tenths of a micrometre to a few micrometres can be
used, all of which are commercially available. They should have an uncertainty of less than 5 %.
6 Factors influencing the measurement results
6.1 Surface roughness
If the coating or its substrate is rough relative to the coating thickness, one or both of the interfaces of
the coating cross-section can be too irregular to permit accurate measurement of the average thickness
in the field of view. In this case, it can be helpful to use software solutions, which can identify the
boundary lines of the coating and either determine its area and divide it by the image width or place
automatically, for example, 100 measurement lines in order to calculate an average coating thickness.
6.2 Taper of cross-section
If the plane of the cross-section is not perpendicular to the plane of the coating, the measured thickness
will be greater than the true thickness. For example, an inclination of 10° to the perpendicular will
contribute a 1,5 % error.
NOTE This source of error is also known as cosine error in the small-angle approximation.
6.3 Specimen tilt
Any tilt of the specimen (plane of cross-section) with respect to the SEM beam can result in an
inaccurate measurement.
NOTE 1 If the tilt of the test specimen is different from that used for calibration, inaccuracies can result.
NOTE 2 This source of error is also known as cosine error in the small-angle approximation.
6.4 Coating deformation
Detrimental deformation of the coating can be caused by excessive temperature or pressure during the
mounting and preparation of cross-sections of soft coatings or coatings that melt at low temperatures,
and by excessive abrasion of brittle materials during preparation of cross-sections.
6.5 Rounding of edges of the coating
If the edge of the coating cross-section is rounded, i.e. if the coating cross-section is not completely flat
up to its edges, the observed thickness can differ from the true thickness. Edge rounding can be caused
by improper mounting, grinding, polishing, or etching (see 6.6 and A.2).
6.6 Plating a protection layer
Overplating of the test specimen, i.e. plating a protection layer onto the test specimen, serves to protect
the coating edges during preparation of cross-sections and thus to prevent an inaccurate measurement.
Removal of the coating material during surface preparation for overplating can cause a low thickness
measurement.
6.7 Etching
Optimum etching will produce a clearly defined and narrow dark line at the interface between the two
materials. A wide or poorly defined line can result in an inaccurate measurement.
NOTE Etching is usually applied for the microscopic method (see ISO 1463) and can be useful for relatively
thick coatings in the SEM, too, especially when individual layers from the same material need to be distinguished
and there is no or too weak material contrast in the back scattered electron image (see 6.9). For (very) thin
coatings, etching has often a negative effect on the measurement uncertainty.
...

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Frequently Asked Questions

SIST EN ISO 9220:2022 is a standard published by the Slovenian Institute for Standardization (SIST). Its full title is "Metallic coatings - Measurement of coating thickness - Scanning electron microscope method (ISO 9220:2022)". This standard covers: This document specifies a destructive method for the measurement of the local thickness of metallic and other inorganic coatings by examination of cross-sections with a scanning electron microscope (SEM). The method is applicable for thicknesses up to several millimetres, but for such thick coatings it is usually more practical to use a light microscope (see ISO 1463). The lower thickness limit depends on the achieved measurement uncertainty (see Clause 10). NOTE       The method can also be used for organic layers when they are neither damaged by the preparation of the cross-section nor by the electron beam during imaging.

This document specifies a destructive method for the measurement of the local thickness of metallic and other inorganic coatings by examination of cross-sections with a scanning electron microscope (SEM). The method is applicable for thicknesses up to several millimetres, but for such thick coatings it is usually more practical to use a light microscope (see ISO 1463). The lower thickness limit depends on the achieved measurement uncertainty (see Clause 10). NOTE       The method can also be used for organic layers when they are neither damaged by the preparation of the cross-section nor by the electron beam during imaging.

SIST EN ISO 9220:2022 is classified under the following ICS (International Classification for Standards) categories: 17.040.20 - Properties of surfaces; 25.220.40 - Metallic coatings. The ICS classification helps identify the subject area and facilitates finding related standards.

SIST EN ISO 9220:2022 has the following relationships with other standards: It is inter standard links to SIST EN ISO 9220:1999. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.

You can purchase SIST EN ISO 9220:2022 directly from iTeh Standards. The document is available in PDF format and is delivered instantly after payment. Add the standard to your cart and complete the secure checkout process. iTeh Standards is an authorized distributor of SIST standards.

この記事は、SIST EN ISO 9220:2022規格について説明しています。この規格は、走査型電子顕微鏡(SEM)を使用して金属およびその他の無機コーティングの局所的な厚さを破壊的な方法で測定する手法を定めています。この手法は数ミリメートルまでの厚さに対して適用可能ですが、そうした厚いコーティングの場合には、光学顕微鏡の使用が一般的により実用的です(ISO 1463を参照)。最小厚さは、測定の不確かさによって異なります(10節参照)。 ただし、この手法は、クロスセクションの準備時や電子ビームによるイメージング中に損傷しない限り、有機層の厚さも測定することができます。

The article discusses the SIST EN ISO 9220:2022 standard, which focuses on measuring the thickness of metallic and other inorganic coatings using a scanning electron microscope (SEM). This method is destructive and involves examining cross-sections. It is suitable for coatings of various thicknesses, although for thicker coatings, a light microscope may be more practical. The accuracy of the measurement depends on the achieved measurement uncertainty. Additionally, the SEM method can also be used for organic layers as long as they are not damaged during cross-section preparation or imaging with the electron beam.

이 문서는 스캔전자현미경(SEM)을 사용하여 금속 및 기타 무기질 코팅의 국부 두께를 파괴적인 방법으로 측정하는 표준인 SIST EN ISO 9220:2022에 대해 설명하고 있습니다. 이 방법은 몇 밀리미터까지의 두께에 대해서 적용 가능하지만, 이러한 두꺼운 코팅의 경우 광학현미경을 사용하는 것이 보통 더 실용적입니다 (ISO 1463 참조). 최소 두께는 측정의 불확도에 따라 다릅니다 (10 절 참조). 참고로, 이 방법은 준비과정에서 손상되거나 전자 빔으로 인해 이미징이 손상되지 않은 경우 유기층의 두께도 측정할 수 있습니다.

The article discusses the SIST EN ISO 9220:2022 standard, which establishes a method for measuring the thickness of metallic and other inorganic coatings using a scanning electron microscope (SEM). This technique is particularly useful for coatings that are several millimeters thick, although a light microscope may be more practical for thicker coatings. It should be noted that this method can also be used for measuring the thickness of organic layers as long as they are not damaged during the process.

기사 제목: SIST EN ISO 9220:2022 - 금속 도금 - 도금 두께 측정 - 주사 전자 현미경 방법 (ISO 9220:2022) 기사 내용: 이 문서는 주사 전자 현미경(SEM)을 사용하여 금속 및 기타 무기질 도금의 지역 두께를 측정하기 위한 파괴적인 방법을 명시합니다. 이 방법은 몇 밀리미터까지의 두께에 적용될 수 있으나 그런 두꺼운 도금의 경우 광학 현미경을 사용하는 것이 더 실용적입니다(ISO 1463 참조). 최소 두께 한계는 측정 불확도에 따라 다릅니다(10 절 참조). 참고: 이 방법은 교차섹션 제작이나 전자 빔 이미징 과정에서 손상되지 않는 한 유기 층에도 사용할 수 있습니다.

記事タイトル:SIST EN ISO 9220:2022 - 金属めっき - めっき厚さの測定 - 走査型電子顕微鏡法(ISO 9220:2022) 記事内容:この文書では、走査型電子顕微鏡(SEM)を使用して、金属および他の無機めっきの局所的な厚さを破壊的な方法で測定することを規定しています。この方法は数ミリメートルまでの厚さに適用されますが、そのような厚いめっきに対しては、一般に光学顕微鏡を使用する方が実用的です(ISO 1463参照)。最小の厚さの制限は、測定の不確かさによって異なります(10条参照)。 注:この方法は、クロスセクションの作製や電子ビームによるイメージング中に損傷がない限り、有機層にも使用することができます。