IEC 62047-22:2014

IEC 62047-22 ®
Edition 1.0 2014-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Semiconductor devices – Micro-electromechanical devices –
Part 22: Electromechanical tensile test method for conductive thin films on
flexible substrates
Dispositifs à semiconducteurs – Dispositifs microélectromécaniques –
Partie 22: Méthode d'essai de traction électromécanique pour les couches
minces conductrices sur des substrats souples

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.

IEC Central Office Tel.: +41 22 919 02 11
3, rue de Varembé Fax: +41 22 919 03 00
CH-1211 Geneva 20 info@iec.ch
Switzerland www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and
bibliographical information on IEC International Standards, electrical terms containing more than 30 000 terms and
Technical Specifications, Technical Reports and other definitions in English and French, with equivalent terms in 14
documents. Available for PC, Mac OS, Android Tablets and additional languages. Also known as the International
iPad. Electrotechnical Vocabulary (IEV) online.

IEC publications search - www.iec.ch/searchpub IEC Glossary - std.iec.ch/glossary
The advanced search enables to find IEC publications by a More than 55 000 electrotechnical terminology entries in
variety of criteria (reference number, text, technical English and French extracted from the Terms and Definitions
committee,…). It also gives information on projects, replaced clause of IEC publications issued since 2002. Some entries
and withdrawn publications. have been collected from earlier publications of IEC TC 37,

77, 86 and CISPR.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Customer Service Centre - webstore.iec.ch/csc
details all new publications released. Available online and If you wish to give us your feedback on this publication or
also once a month by email. need further assistance, please contact the Customer Service
Centre: csc@iec.ch.
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.

Catalogue IEC - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
Application autonome pour consulter tous les renseignements
Le premier dictionnaire en ligne de termes électroniques et
bibliographiques sur les Normes internationales,
électriques. Il contient plus de 30 000 termes et définitions en
Spécifications techniques, Rapports techniques et autres
anglais et en français, ainsi que les termes équivalents dans
documents de l'IEC. Disponible pour PC, Mac OS, tablettes
14 langues additionnelles. Egalement appelé Vocabulaire
Android et iPad.
Electrotechnique International (IEV) en ligne.

Recherche de publications IEC - www.iec.ch/searchpub
Glossaire IEC - std.iec.ch/glossary
Plus de 55 000 entrées terminologiques électrotechniques, en
La recherche avancée permet de trouver des publications IEC
en utilisant différents critères (numéro de référence, texte, anglais et en français, extraites des articles Termes et
comité d’études,…). Elle donne aussi des informations sur les Définitions des publications IEC parues depuis 2002. Plus
projets et les publications remplacées ou retirées. certaines entrées antérieures extraites des publications des

CE 37, 77, 86 et CISPR de l'IEC.
IEC Just Published - webstore.iec.ch/justpublished

Service Clients - webstore.iec.ch/csc
Restez informé sur les nouvelles publications IEC. Just
Published détaille les nouvelles publications parues. Si vous désirez nous donner des commentaires sur cette
Disponible en ligne et aussi une fois par mois par email. publication ou si vous avez des questions contactez-nous:
csc@iec.ch.
IEC 62047-22 ®
Edition 1.0 2014-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Semiconductor devices – Micro-electromechanical devices –

Part 22: Electromechanical tensile test method for conductive thin films on

flexible substrates
Dispositifs à semiconducteurs – Dispositifs microélectromécaniques –

Partie 22: Méthode d'essai de traction électromécanique pour les couches

minces conductrices sur des substrats souples

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX K
ICS 31.080.99 ISBN 978-2-8322-1649-1

– 2 – IEC 62047-22:2014 © IEC 2014
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms, definitions, symbols and designations . 5
3.1 Terms and definitions. 5
3.2 Symbols and designations . 6
4 Test piece . 6
4.1 General . 6
4.2 Shape of a test piece . 6
4.3 Measurement of dimensions . 7
5 Testing method and test apparatus . 7
5.1 Test principle . 7
5.2 Test machine . 7
5.3 Test procedure. 9
5.4 Test environment . 9
6 Test report . 9

Figure 1 – Bilayered test piece. 6
Figure 2 – Schematic of an electromechanical test machine . 8
Figure 3 – Electromechanical tensile grip . 9

Table 1 – Symbols and designations of a test piece . 6

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
MICRO-ELECTROMECHANICAL DEVICES –

Part 22: Electromechanical tensile test method
for conductive thin films on flexible substrates

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62047-22 has been prepared by subcommittee 47F: Micro-
electromechanical systems, of IEC technical committee 47: Semiconductor devices.
The text of this standard is based on the following documents:
FDIS Report on voting
47F/186/FDIS 47F/190/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

– 4 – IEC 62047-22:2014 © IEC 2014
A list of all parts in the IEC 62047 series, published under the general title Semiconductor
devices – Micro-electromechanical devices, can be found in the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
SEMICONDUCTOR DEVICES –
MICRO-ELECTROMECHANICAL DEVICES –

Part 22: Electromechanical tensile test method
for conductive thin films on flexible substrates

1 Scope
This part of IEC 62047 specifies a tensile test method to measure electromechanical
properties of conductive thin micro-electromechanical systems (MEMS) materials bonded on
non-conductive flexible substrates. Conductive thin-film structures on flexible substrates are
extensively utilized in MEMS, consumer products, and flexible electronics. The electrical
behaviours of films on flexible substrates differ from those of freestanding films and
substrates due to their interfacial interactions. Different combinations of flexible substrates
and thin films often lead to various influences on the test results depending on the test
conditions and the interfacial adhesion. The desired thickness of a thin MEMS material is
50 times thinner than that of the flexible substrate, whereas all other dimensions are similar to
each other.
2 Normative references
The 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 edition of the referenced document (including any
amendments) applies.
IEC 62047-2:2006, Semiconductor devices – Micro-electromechanical devices – Part 2:
Tensile testing method of thin film materials
IEC 62047-3:2006, Semiconductor devices – Micro-electromechanical devices – Part 3: Thin
film standard test piece for tensile testing
IEC 62047-8:2011, Semiconductor devices – Micro-electromechanical devices – Part 8: Strip
bending test method for tensile property measurement of thin films
ISO 527-3:1995, Plastics – Determination of tensile properties – Part 3: Test conditions for
films and sheets
3 Terms, definitions, symbols and designations
3.1 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1.1
gauge factor
G
F
ratio of the change in electrical resistance divided by the original resistance (R , resistance in
o
the undeformed configuration) to engineering strain (e)
Note 1 to entry: Gauge factor is expressed as G = (R – R )/R e, where R is the electrical resistance in the
F O O
deformed configuration.
– 6 – IEC 62047-22:2014 © IEC 2014
3.1.2
elongation at electrical failure
A
telic
engineering strain value at which the electrical resistance starts to exceed a predefined limit
3.2 Symbols and designations
The shape of the test piece and symbols are presented in Figure 1 and Table 1, respectively.
The overall shape of the test piece is similar to a conventional thin-film or sheet test piece (in
accordance with ISO 527-3) for tensile tests, but it has a multilayered structure.
l b
l
IEC  1841/14
Figure 1 – Bilayered test piece

Table 1 – Symbols and designations of a test piece
Symbol Unit Designation
l µm Gauge length for strain and resistance change measurements
l Overall length
µm
h Thickness of the first layer (or thin film)
µm
h µm Thickness of the second layer (or substrate)
b µm Width
4 Test piece
4.1 General
The test piece shall be prepared using the same fabrication process as the actual device
fabricated for flexible MEMS. Machining of the test piece shall be performed carefully to
prevent formation of cracks or flaws and delamination in the test piece. Chemical etching or
mechanical machining with a very sharp tool shall be applied to shape the test piece.
4.2 Shape of a test piece
The shape of a test piece is shown in Figure 1. Because the change in electrical resistance is
related to strain or stress, electrical resistance shall be measured in a region of nearly
uniform strain. To measure electrical resistance, attach lead wires to the conductive thin film
of the test piece. Conductive thin films deposited on flexible substrates are usually very thin
compared with the diameter of the lead wires, and the lead wires are easily detached from the
test piece during the electromechanical test. Therefore, place the lead wires in tensile grips
and secure the electrical contact by applying mechanical contact force. Tensile grips are
described in detail in 5.2. For uniform strain distribution, the shape of the test piece is a
rectangular strip, not a dog bone (see Figure 1 of ISO 527-3:1995 for other rectangular test
pieces). To eliminate the effect of the fixed boundary near the grips (l ), the gauge length
shall be at least 20 times larger than the width (b).
h h
2 1
4.3 Measurement of dimensions
To analyze the test results, the test piece dimensions shall be accurately measured because
the dimensions are used to determine the mechanical properties of test materials. Gauge
length (l ), width (b), and thickness (h , h ) should be measured with an error of less than
1 1 2
± 5 %. Thickness measurement shall be performed according to Annex C of IEC 62047-
2:2006 and to Clause 6 of IEC 62047-3:2006. There can be some combinations of thin film
and substrate where it is difficult to fulfil the tolerance of thickness measurement. In this case
the average and the standard deviation of the thickness measurement should be reported.
5 Testing method and test apparatus
5.1 Test principle
The test is performed by applying a tensile load to a test piece. The tensile strain induced by
the tensile load shall be uniform in a pre-defined gauge section in the elastic region of the
substrate or the thin MEMS material. To measure the change in electrical resistance along
with the change in mechanical strain, carefully select the gauge section. The gauge section
for measuring mechanical strain shall be coincident with or scalable to that for measuring
electrical resistance. This constraint is an important point in this standard.
5.2 Test machine
The test machine is similar to a conventional tensile test machine except that it is capable of
measuring electrical resistance during the test. The electrical measurement circuit can be a 2-
wire or 4-wire method depending on the magnitude of the electrical resistance of the test
piece. For a test piece with an electrical resistance greater than 1 kΩ, a 2-wire method can be
utilized for ease of measurement. For a test piece with an electrical resistance less than 1 kΩ,
the 4-wire method (Kelvin method) shall be utilized to eliminate contact and lead wire
resistance. A schematic of the test machine is shown in Figure 2a). For a material sensitive to
stress concentration and local plastic deformation, a test piece with rounded, gripped ends
shall be used according to Figure 1 of IEC 62047-2:2006, and the test machine in Figure 2b)
should be used.
– 8 – IEC 62047-22:2014 © IEC 2014

IEC  1842/14
a) Test machine setup using grips with an electrical contact
IEC  1843/14
b) Test machine setup using electrical contacts on the test piece

Key
1 Machine frame  2 Grip
3 Loadcell  4 Actuator
5 Volt meter  6 Specimen
Figure 2 – Schematic of an electromechanical test machine
To measure electrical resistance, a tensile grip with electrical contacts is utilized, and the
number of electrical contacts is dependent on the electrical measurement method (2-wire or
4-wire method). A schematic of the tensile grip is shown in Figure 3. In this standard, strain is
estimated from the grip-to-grip distance. An optical or mechanical extensometer shall be used
to measure the grip-to-grip distance.

IEC  1844/14
IEC  1845/14
a) Photograph of the installed tensile grip b) Schematic of the tensile grip

Key
1 Probe pin  2 Bolt
3 Insulating jig  4 Specimen
Figure 3 – Electromechanical tensile grip
5.3 Test procedure
The test procedure is as follows:
a) Fix the test piece using the test apparatus tensile gri
...