IEC 62951-1:2017

Semiconductor devices - Flexible and stretchable semiconductor devices - Part 1: Bending test method for conductive thin films on flexible substrates

IEC 62951-1:2017(E) specifies a bending test method to measure the electromechanical properties or flexibility of conductive thin films deposited or bonded on flexible non-conductive substrates. Conductive thin films on flexible substrates are extensively used in flexible electronic devices and flexible semiconductors. Conductive thin films include any films deposited or bonded onto a non-conductive flexible substrate such as thin metal film, transparent conducting electrode, and thin silicon film. The electrical and mechanical behaviours of thin films on flexible substrates differ from those of freestanding films and substrates due to their interfacial interactions and adhesion between the film and substrate. The object of this standard is to establish simple and repeatable test methods for evaluating the electromechanical properties or flexibility of conductive thin films on flexible substrate. The bending test methods include outer bending test and inner bending test.

General Information

• Status: Published
• Publication Date: 09-Apr-2017
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 29.180 - Transformers. Reactors
• ICS: 31.080.99 - Other semiconductor devices
• Technical Committee: TC 47 - Semiconductor devices
• Drafting Committee: WG 6 - TC 47/WG 6
• Current Stage: PPUB - Publication issued
• Start Date: 05-May-2017
• Completion Date: 10-Apr-2017

Standards Content (Sample)

IEC 62951-1 ®
Edition 1.0 2017-04
INTERNATIONAL
STANDARD
colour
inside
Semiconductor devices – Flexible and stretchable semiconductor devices –
Part 1: Bending test method for conductive thin films on flexible substrates
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IEC 62951-1 ®
Edition 1.0 2017-04
INTERNATIONAL
STANDARD
colour
inside
Semiconductor devices – Flexible and stretchable semiconductor devices –

Part 1: Bending test method for conductive thin films on flexible substrates

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.080.99 ISBN 978-2-8322-3896-7

– 2 – IEC 62951-1:2017 © IEC 2017
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and symbols. 5
3.1 Terms and definitions . 5
3.2 Symbols and designations . 6
4 Test piece . 7
4.1 Design of test piece . 7
4.2 Preparation of a test piece . 7
4.3 Measurement of dimensions . 7
4.4 Storage prior to testing . 8
5 Testing method and test apparatus . 8
5.1 General . 8
5.2 Test apparatus . 8
5.3 Measurement of electrical resistance . 8
5.4 Test procedure . 9
5.5 Observation of cracks in test piece . 9
5.6 Data analysis . 9
5.7 Test environment . 9
6 Test report . 10
Annex A (informative) X-Y-θ bending test method . 11
Annex B (informative) Data analysis: Calculation of bending radius and bending strain . 13
B.1 Calculation of bending radius . 13
B.2 Calculation of bending strain of the film . 13
Bibliography . 15

Figure 1 – Shape of a test piece . 7
Figure 2 – Bending test apparatus . 8
Figure A.1 – X-Y-θ bending test method . 11
Figure A.2 – Schematic of the bending geometry in X-Y-θ system . 12
Figure B.1 – Geometrical shape of bent test piece . 13

Table 1 – Symbols and designations of a test piece . 7

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES – FLEXIBLE AND
STRETCHABLE SEMICONDUCTOR DEVICES –

Part 1: Bending test method for conductive
thin films on flexible substrates

FOREWORD
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International Standard IEC 62951-1 has been prepared by IEC technical committee 47:
Semiconductor devices.
The text of this International Standard is based on the following documents:
FDIS Report on voting
47/2369/FDIS 47/2384/RVD
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 62951-1:2017 © IEC 2017
A list of all parts in the IEC 62951 series, published under the general title Semiconductor
devices – Flexible and stretchable semiconductor devices, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
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related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
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SEMICONDUCTOR DEVICES – FLEXIBLE AND
STRETCHABLE SEMICONDUCTOR DEVICES –

Part 1: Bending test method for conductive
thin films on flexible substrates

1 Scope
This part of IEC 62951 specifies a bending test method to measure the electromechanical
properties or flexibility of conductive thin films deposited or bonded on flexible non-conductive
substrates. Conductive thin films on flexible substrates are extensively used in flexible
electronic devices and flexible semiconductors. Conductive thin films include any films
deposited or bonded onto a non-conductive flexible substrate such as thin metal film,
transparent conducting electrode, and thin silicon film. The electrical and mechanical
behaviours of thin films on flexible substrates differ from those of freestanding films and
substrates due to their interfacial interactions and adhesion between the film and substrate.
The object of this standard is to establish simple and repeatable test methods for evaluating
the electromechanical properties or flexibility of conductive thin films on flexible substrate.
The bending test methods include outer bending test and inner bending test.
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.
IEC 62047-2:2006, Semiconductor devices – Micro-electromechanical devices – Part 2:
Tensile testing method of thin film materials
IEC 62047-22:2014, Semiconductor devices – Micro-electromechanical devices – Part 22:
Electromechanical tensile test method for conductive thin films on flexible substrates
3 Terms, definitions and symbols
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
bending radius of curvature
r
radius of curvature that the test piece shows in bending test
...