IEC 62047-31:2019

IEC 62047-31 ®
Edition 1.0 2019-04
INTERNATIONAL
STANDARD
colour
inside
Semiconductor devices – Micro-electromechanical devices –
Part 31: Four-point bending test method for interfacial adhesion energy of
layered MEMS materials
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.

IEC Central Office Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
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 corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
details all new publications released. Available online and 67 000 electrotechnical terminology entries in English and
once a month by email. French extracted from the Terms and Definitions clause of
IEC publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or CISPR.

need further assistance, please contact the Customer Service

Centre: sales@iec.ch.
IEC 62047-31 ®
Edition 1.0 2019-04
INTERNATIONAL
STANDARD
colour
inside
Semiconductor devices – Micro-electromechanical devices –

Part 31: Four-point bending test method for interfacial adhesion energy of

layered MEMS materials
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.080.99 ISBN 978-2-8322-6717-2

– 2 – IEC 62047-31:2019 © IEC 2019
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
4.4 Evaluation of energy release rate . 7
5 Testing method and test apparatus . 7
5.1 Test principle . 7
5.2 Test machine . 8
5.3 Test procedure . 8
5.4 Test environment . 9
6 Test report . 9
Annex A (informative) Failure modes during the four-point bending test . 10
A.1 General . 10
A.2 Some failure modes . 10
Bibliography . 12

Figure 1 – Four-point bending test piece . 6
Figure 2 – Picture of a four-point bending fixture . 9
Figure A.1 – Several failure modes during the four-point bending test . 11

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

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

Part 31: Four-point bending test method for interfacial
adhesion energy of layered MEMS materials

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 62047-31 has been prepared by subcommittee 47F: Micro-
electromechanical systems, of IEC technical committee 47: Semiconductor devices.
The text of this International Standard is based on the following documents:
FDIS Report on voting
47F/326/FDIS 47F/331RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

– 4 – IEC 62047-31:2019 © IEC 2019
A list of all parts in the IEC 62047 series, published under the general title Semiconductor
devices – Micro-electromechanical devices, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

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 31: Four-point bending test method for interfacial
adhesion energy of layered MEMS materials

1 Scope
This part of IEC 62047 specifies a four-point bending test method for measuring interfacial
adhesion energy of the weakest interface in the layered micro-electromechanical systems
(MEMS) based on the concept of fracture mechanics. In a variety of MEMS devices, there are
many layered material interfaces, and their adhesion energies are critical to the reliability of
the MEMS devices. The four-point bending test utilizes a pure bending moment applied to a
test piece of layered MEMS device, and the interfacial adhesion energy is measured from the
critical bending moment for the steady state cracking in the weakest interface. This test
method applies to MEMS devices with thin film layers deposited on semiconductor substrates.
The total thickness of the thin film layers should be 100 times less than the thickness of a
supporting substrate (typically a silicon wafer piece).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
There are no normative references in this document.
3 Terms, definitions, symbols and designations
3.1 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:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
energy release rate
G
strain energy per unit surface area, which is released during the incremental growth of a crack
Note 1 to entry: The energy release rate can be regarded as the crack driving force, and its unit is given in J/m .
3.1.2
interfacial adhesion energy
G
C
critical energy release rate at the moment of crack extension
Note 1 to entry: Its unit is given in: J/m .

– 6 – IEC 62047-31:2019 © IEC 2019
3.2 Symbols and designations
The shape of the test piece and the symbols are presented in Figure 1 and Table 1,
respectively. The overall shape of the test piece is similar to a sandwiched cantilever beam,
and it should have a pre-crack or a notch for crack initiation. After initiation of the crack, the
crack follows the weakest interface in the layered materials system.

Key
1 layered material
2 notched pre-crack
3 interfacial crack
Figure 1 – Four-point bending test piece
Table 1 – Symbols and designations of a test piece
Symbol Unit Designation
L mm Spacing between two adjacent pins
b mm Width
h μm Thickness of the supporting structure
P N Force for driving crack
4 Test piece
4.1 General
The test piece for the layered MEMS materials shall be prepared using the same fabrication
process that applies to actual MEMS devices. Machining of the test piece shall b
...