IEC 62951-2:2019

IEC 62951-2 ®
Edition 1.0 2019-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Semiconductor devices – Flexible and stretchable semiconductor devices –
Part 2: Evaluation method for electron mobility, sub-threshold swing, and
threshold voltage of flexible devices

Dispositifs à semiconducteurs – Dispositifs à semiconducteurs souples et
extensibles –
Partie 2: Méthode d’évaluation pour la mobilité des électrons, la pente en régime
de sous-seuil et la tension de seuil des dispositifs souples

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IEC 62951-2 ®
Edition 1.0 2019-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Semiconductor devices – Flexible and stretchable semiconductor devices –

Part 2: Evaluation method for electron mobility, sub-threshold swing, and

threshold voltage of flexible devices

Dispositifs à semiconducteurs – Dispositifs à semiconducteurs souples et

extensibles –
Partie 2: Méthode d’évaluation pour la mobilité des électrons, la pente en régime

de sous-seuil et la tension de seuil des dispositifs souples

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.080.99 ISBN 978-2-8322-6817-9

– 2 – IEC 62951-2:2019 © IEC 2019
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Test method . 6
4.1 General . 6
4.2 Test of electrical characteristics before bending . 7
4.3 Test of electrical characteristics under bending . 8
4.4 Test report . 9
Bibliography . 10

Figure 1 – Procedure for measurement of flexible thin-film transistor . 7
Figure 2 – Schematic circuit diagram of the test . 8
Figure 3 – Configuration for the TFT bending test . 9

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

Part 2: Evaluation method for electron mobility, sub-threshold swing, and
threshold voltage of flexible devices

FOREWORD
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International Standard IEC 62951-2 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
47/2541/FDIS 47/2564/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 62951-2:2019 © IEC 2019
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 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.
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SEMICONDUCTOR DEVICES –
FLEXIBLE AND STRETCHABLE SEMICONDUCTOR DEVICES –

Part 2: Evaluation method for electron mobility, sub-threshold swing, and
threshold voltage of flexible devices

1 Scope
This part of IEC 62951 specifies terms, definitions, symbols, configurations and evaluation
methods that can be used to evaluate and determine the performance characteristics of
flexible thin-film transistor (TFT) devices. This document specifies test methods and
characteristic parameters for accurately evaluating the performance and reliability in practical
use of flexible TFT devices under the bending status.
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:
• • IEC Electropedia: available at http://www.electropedia.org/
• • ISO Online browsing platform: available at http://www.iso.org/obp
3.1
flexible thin-film transistor
flexible TFT
thin-film transistor fabricated on mechanically flexible substrates such as polymers and metal
foils
Note 1 to entry: This note applies to the French language only.
3.2
mobility
quantity equal to the quotient of the modulus of the mean velocity of a
charge carrier (electron) in the direction of an electric field by the modulus of the field strength
[SOURCE: IEC 60050-521:2002, 521-02-58, modified — "electron" has been added.]
3.3
sub-threshold swing
S
parameter for quantifying how sharply the transistor is turned off by the gate voltage, de
...