Semiconductor devices - Micro-electromechanical devices - Part 26: Description and measurement methods for micro trench and needle structures

This part of IEC 62047 specifies descriptions of trench structure and needle structure in a
micrometer scale. In addition, it provides examples of measurement for the geometry of both
structures. For trench structures, this standard applies to structures with a depth of 1 μm to
100 μm; walls and trenches with respective widths of 5 μm to 150 μm; and aspect ratio of
0,006 7 to 20. For needle structures, the standard applies to structures with three or four
faces with a height, horizontal width and vertical width of 2 μm or larger, and with dimensions
that fit inside a cube with sides of 100 μm.
This standard is applicable to the structural design of MEMS and geometrical evaluation after
MEMS processes.

Halbleiterbauelemente - Bauelemente der Mikrosystemtechnik - Teil 26: Beschreibung und Messverfahren für Mikro-Rillen und Nadelstrukturen

Dispositifs à semiconducteurs - Dispositifs microélectromécaniques - Partie 26: Description et méthodes de mesure pour structures de microtranchées et de microaiguille

L'IEC 62047-26:2016 spécifie des descriptions de structures de tranchées et de structures d'aiguille à l'échelle micrométrique. En outre, elle donne des exemples de mesures de la géométrie des deux structures. Pour les structures de tranchées, la présente norme s'applique à des structures de profondeur comprise entre 1 µm et 100 µm, avec des parois et des tranchées de largeur comprise entre 5 µm et 150 µm et avec un rapport hauteur/largeur compris entre 0,006 7 et 20. Pour les structures d'aiguille, la norme s'applique à des structures à trois ou quatre faces dont la hauteur, la largeur horizontale et la largeur verticale sont supérieures ou égales à 2 µm, et dont les dimensions permettent de placer chaque structure dans un cube de 100 µm de côté.
La présente norme s'applique à la conception structurelle de procédés MEMS et à leur appréciation géométrique.

Polprevodniški elementi - Mikroelektromehanski elementi - 26. del: Opis in merilne metode za mikrokanalske in iglaste strukture

Ta del standarda IEC 62047 določa opise kanalske in iglaste strukture v velikosti mikrometra. Poleg tega vsebuje primere merjenja za geometrijo obeh struktur. Pri kanalskih strukturah se ta standard uporablja za strukture z globino od 1 μm do 100 μm; zidove in kanale s širino od 5 μm do 150 μm; in razmerje med višino in širino od 0,0067 do 20. Pri iglastih strukturah se ta standard uporablja za strukture s tremi ali štirimi ploskvami z višino, vodoravno širino in navpično širino vsaj 2 μm in z dimenzijami, ki se prilegajo notranjosti kocke s stranicami 100 μm.
Ta standard se uporablja za strukturne zasnove MEMS in geometrično vrednotenje po postopkih MEMS.

General Information

Status
Published
Publication Date
23-May-2016
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
11-May-2016
Due Date
16-Jul-2016
Completion Date
24-May-2016

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SLOVENSKI STANDARD
SIST EN 62047-26:2016
01-julij-2016
Polprevodniški elementi - Mikroelektromehanski elementi - 26. del: Opis in merilne
metode za mikrokanalske in iglaste strukture
Semiconductor devices - Micro-electromechanical devices - Part 26: Description and
measurement methods for micro trench and needle structures
Ta slovenski standard je istoveten z: EN 62047-26:2016
ICS:
31.080.01 Polprevodniški elementi Semiconductor devices in
(naprave) na splošno general
SIST EN 62047-26:2016 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 62047-26:2016

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SIST EN 62047-26:2016


EUROPEAN STANDARD EN 62047-26

NORME EUROPÉENNE

EUROPÄISCHE NORM
April 2016
ICS 31.080.99

English Version
Semiconductor devices - Micro-electromechanical devices -
Part 26: Description and measurement methods for micro trench
and needle structures
(IEC 62047-26:2016)
Dispositifs à semiconducteurs - Dispositifs Halbleiterbauelemente - Bauelemente der
microélectromécaniques - Partie 26: Description et Mikrosystemtechnik - Teil 26: Beschreibung und
méthodes de mesure pour structures de microtranchées et Messverfahren für Mikro-Rillen und Nadelstrukturen
de microaiguille (IEC 62047-26:2016)
(IEC 62047-26:2016)
This European Standard was approved by CENELEC on 2016-02-11. CENELEC 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 CENELEC 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 CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.


European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2016 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN 62047-26:2016 E

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SIST EN 62047-26:2016
EN 62047-26:2016
European foreword
The text of document 47F/233/FDIS, future edition 1 of IEC 62047-26, prepared by SC 47F "Micro-
electromechanical systems", of IEC/TC 47 "Semiconductor devices" was submitted to the IEC-
CENELEC parallel vote and approved by CENELEC as EN 62047-26:2016.
The following dates are fixed:
(dop) 2016-11-11
• latest date by which the document has to be implemented at
national level by publication of an identical national
standard or by endorsement
(dow) 2019-02-11
• latest date by which the national standards conflicting with
the document have to be withdrawn

Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.
Endorsement notice
The text of the International Standard IEC 62047-26:2016 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following note has to be added for the standard indicated :
ISO 3274:1996 NOTE Harmonized as EN ISO 3274:1997 (not modified).

2

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SIST EN 62047-26:2016




IEC 62047-26

®


Edition 1.0 2016-01




INTERNATIONAL



STANDARD




NORME



INTERNATIONALE
colour

inside










Semiconductor devices – Micro-electromechanical devices –

Part 26: Description and measurement methods for micro trench and needle

structures




Dispositifs à semiconducteurs – Dispositifs microélectromécaniques –

Partie 26: Description et méthodes de mesure pour structures de


microtranchées et de microaiguille













INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


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ICS 31.080.99 ISBN 978-2-8322-3122-7



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SIST EN 62047-26:2016
– 2 – IEC 62047-26:2016 © IEC 2016
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Description of trench structures in a micrometer scale . 7
4.1 General . 7
4.2 Symbols and designations . 7
4.3 Description . 9
5 Description of needle structures in a micrometer scale . 9
5.1 General . 9
5.2 Symbols and designations . 9
5.3 Description . 10
6 Measurement method . 10
Annex A (informative) Examples of measurement for trench and needle structures in
a micrometer scale . 11
A.1 General . 11
A.2 Measurement for depth of trench . 11
A.2.1 Field emission type scanning electron microscopy . 11
A.2.2 Coherence scanning interferometer (CSI) . 12
A.2.3 Stylus surface profiler . 14
A.2.4 Confocal laser scanning microscopy . 16
A.2.5 Atomic force microscopy . 17
A.3 Measurement for width of wall and trench at the upper surface of trench . 18
A.3.1 Field emission type scanning electron microscopy . 18
A.3.2 Coherence scanning interferometer . 19
A.3.3 Stylus surface profiler . 19
A.3.4 Confocal laser scanning microscopy . 19
A.3.5 Optical microscopy . 20
A.4 Measurement for side wall angle of trench by field emission type scanning
electron microscopy . 20
A.4.1 Principle of measurement . 20
A.4.2 Preparation of sample . 21
A.4.3 Procedure of measurement . 21
A.4.4 Measurable range . 21
A.5 Measurement for wall and trench width at the bottom of trench by field
emission type scanning ele microscopy . 21
A.5.1 Principle of measurement . 21
A.5.2 Preparation of sample . 21
A.5.3 Procedure of measurement . 21
A.5.4 Measurable range . 21
A.6 Measurement for geometry of needle . 21
A.6.1 Field emission type scanning electron microscopy . 21
A.6.2 Atomic force microscopy . 23
Annex B (informative)  Uncertainty in dimensional measurement . 25
B.1 General . 25
B.2 Basic concepts . 25

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SIST EN 62047-26:2016
IEC 62047-26:2016 © IEC 2016 – 3 –
B.3 Example of evaluating uncertainty of the average depth of trench . 25
B.3.1 Sample and measured data for evaluating uncertainty . 25
B.3.2 Source of uncertainty . 26
B.3.3 Type A evaluation of standard uncertainty . 26
B.3.4 Type B evaluation of standard uncertainty . 26
B.3.5 Combined standard uncertainty . 26
B.3.6 Expanded uncertainty and result . 26
B.3.7 Budget table . 26
Bibliography . 28

Figure 1 – Schematic of example for trench structure in a micrometer scale and its
cross section . 7
Figure 2 – Cross section of trench structure in a micrometer scale . 8
Figure 3 – Cross section of trench structure in a micrometer scale fabricated by a
deep-reactive ion etching process with repeated deposition and etching of silicon . 8
Figure 4 – Schematic of typical needle structures formed of three and four faces . 9
Figure 5 – Front, side and top views of typical needle structures. 10
Figure A.1 – FE-SEM image of trench structure with 5 µm-wide wall and 5 µm-wide
trench . 12
Figure A.2 – Schematic of CSI microscope comprising an equal-light-path
interferometer . 13
Figure A.3 – Measurability for depth of trench structure with a depth of D and a width
of W using a stylus surface profiler . 16
Tu
Figure A.4 – Relationship between shape of AFM probe tip and trench structure . 18
Figure A.5 – Front, side and top views of typical needle structures tilted to the back
side with 30° . 23
Figure A.6 – Relationship between shapes of AFM probe tip and needle structure . 24

Table 1 – Symbols and designations of trench structure in a micrometer scale . 8
Table 2 – Symbols and designations of needle structure in a micrometer scale . 10
Table A.1 – Example of measured data of trench depth . 12
Table A.2 – CSI magnification (objective lens/ imaging lens) for measurement of all
trench . 14
Table B.1 – Example of measured data of trench depth . 25
Table B.2 – Estimation of uncertainty in measurement . 27

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SIST EN 62047-26:2016
– 4 – IEC 62047-26:2016 © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

SEMICONDUCTOR DEVICES –
MICRO-ELECTROMECHANICAL DEVICES –

Part 26: Description and measurement methods for
micro trench and needle structures

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 62047-26 has been prepared by subcommittee 47F:
Microelectromechanical systems, of IEC technical committee 47: Semiconductor devices.
The text of this standard is based on the following documents:
FDIS Report on voting
47F/233/FDIS 47F/239/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.

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SIST EN 62047-26:2016
IEC 62047-26:2016 © IEC 2016 – 5 –
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 publication will remain unchanged until
the stability date indicated on the IEC website 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.

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SIST EN 62047-26:2016
– 6 – IEC 62047-26:2016 © IEC 2016
SEMICONDUCTOR DEVICES –
MICRO-ELECTROMECHANICAL DEVICES –

Part 26: Description and measurement methods for
micro trench and needle structures



1 Scope
This part of IEC 62047 specifies descriptions of trench structure and needle structure in a
micrometer scale. In addition, it provides examples of measurement for the geometry of both
structures. For trench structures, this standard applies to structures with a depth of 1 µm to
100 µm; walls and trenches with respective widths of 5 µm to 150 µm; and aspect ratio of
0,006 7 to 20. For needle structures, the standard applies to structures with three or four
faces with a height, horizontal width and vertical width of 2 µm or larger, and with dimensions
that fit inside a cube with sides of 100 µm.
This standard is applicable to the structural design of MEMS and geometrical evaluation after
MEMS processes.
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.
None.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
trench structure
one or more rectangular structures engraved in a planar substrate, with a constant trapezoidal
cross section profile
3.2
needle structure
projecting structures with a pointed tip formed of three or more faces, formed on a planar
substrate with the plane of symmetry in the vertical plane
3.3
wall and trench
two or more of the trench structures arranged in parallel at regular intervals
3.4
scallop
irregularity formed cyclically in the side walls after a deep-reactive ion etching (DRIE) process
with repeated deposition and selective etching of polymeric passivation layer and then etching
of a silicon substrate

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SIST EN 62047-26:2016
IEC 62047-26:2016 © IEC 2016 – 7 –
4 Description of trench structures in a micrometer scale
4.1 General
This standard specified the method of indicating the cross-sectional geometry of trench
structures with micrometer scale dimensions. Figure 1 is a diagram of the cross section
required for indicating the cross-sectional geometry of trench structures in this standard. The
cross-sectional geometry of trench structures is the cross-sectional shape at a line
longitudinally intersecting the trench structure at right angles as viewed from the upper
surface of the substrate, with an error of ±1° or less.
See Clause 6 and Annex A for the method of measuring the cross-sectional dimensions of
trench structures.
A
A'
±1°
IEC IEC

a) Example of trench structure b) Cross section of trench structure
at the A_A’ line
Figure 1 – Schematic of example for trench structure
in a micrometer scale and its cross section
4.2 Symbols and designations
The cross section of a typical trench structure is shown in Figure 2, and the symbols,
designations and units used for indicating the cross section of the trench structures are listed
in Table 1.
The horizontal datum line for indicating the cross section in Figure 2 is a straight line
approximating the upper surface of the planar substrate. The vertical datum line is defined as
a line intersecting the horizontal datum line at right angles. The trench side wall is indicated
by its straight line approximation. The bottom of trench is expressed as its approximate
straight or curved line. On the upper surface of the trench structure, the wall is defined as the
area that is considered same as the horizontal datum line without etching, and the trench is
defined as the etched area. According to these definitions, the widths of the wall and trench at
the upper surface are expressed as shown in Figure 2. The trench side wall angle is defined
as the angle between the horizontal datum line and approximate line of the side wall, and it is
indicated with a value measured clockwise from the horizontal datum line positioned on the
top of the wall to the trench side wall by the shortest distance, as shown in Figure 2. The
widths of the wall and trench at the bottom of the trench are expressed by distances between
intersection points with the approximate line of the side wall and approximate straight or
curved line at the bottom of the trench. The depth of the trench is defined as the shortest
distance from the horizontal datum line at the middle of the trench to the bottom surface of the
trench.
When the trench structure is fabricated by the DRIE process with repeated deposition and
selective etching of polymeric passivation layer and then etching of a silicon substrate,
scallops are formed in the trench side walls after etching. Figure 3 shows a cross section of a
trench structure with inverse taper side walls prepared with the DRIE etching process,
including symbols for the geometry.

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SIST EN 62047-26:2016
– 8 – IEC 62047-26:2016 © IEC 2016
W (N)
PU

W W
WU TU

Sidewall with ordered taper
θ
Sidewall with inverse taper
W W
WB TB

W (N)
PB


IEC
Figure 2 – Cross section of trench structure in a micrometer scale
W (N)
PU

W W
WU TU

Sidewall with inverse taper
θ
S
x
W
W
TB
WB

Scallops
W (N)
PB

IEC

Figure 3 – Cross section of trench structure in a micrometer scale fabricated by a deep-
reactive ion etching process with repeated deposition and etching of silicon
Table 1 – Symbols and designations of trench structure in a micrometer scale
Symbol Unit Designation
W Width of wall part at the upper surface
µm
WU
W Width of trench part at the upper surface
µm
TU
W Width of wall part at the bottom of trench
µm
WB
W Width of trench part at the bottom of trench
µm
TB
W (N) µm Distance of N pitches of Wall and Trench at the upper surface
PU
W (N) Distance of N pitches of Wall and Trench at the bottom of trench
µm
PB
N – Number of pitches
D Depth of trench at the center of trench
µm
Deg Sidewall angle
θ
S Horizontal distance of scallop
µm
x
R Mean vertical distance of scallop
S µm
m

D
D
R
sm

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SIST EN 62047-26:2016
IEC 62047-26:2016 © IEC 2016 – 9 –
4.3 Description
Trench structures shall be dimensioned using Figure 2 or Figure 3 in accordance with 4.1 and
1
4.2. See ISO 129-1[1] for indicating dimensions.
5 Description of needle structures in a micrometer scale
5.1 General
This standard specifies the method of indicating the geometry of needle structures in a
micrometer scale. Figure 4 shows an external view of a typical needle structure. The needle
structures defined in this standard are projecting structures with a pointed tip formed of three
or four faces, formed on a planar substrate with the plane of symmetry in the vertical plane.
The hatching plane in the figure is the plane of symmetry. The bottom face of the needle
structure corresponds to the surface of the planar substrate.
See Clause 6 and Annex A for the method of measuring the geometry of needle structures.
100 µm 100 µm
100 µm
100 µm
Plane of
Plane of
symmetry
symmetry
IEC

Figure 4 – Schematic of typical needle structures formed of three and four faces
5.2 Symbols and designations
Figure 5 is a three-view drawing of a typical needle structure. Table 2 lists the symbols,
designations and units used for indicating the geometrical dimensions of the needle structures.
The front position of the needle structures is defined as the position where the structure
shows bilateral symmetry with the plane of symmetry in the center and where the bottom face
of the structure corresponds to the horizontal plane. The front position of needle structures
with tips formed of three faces is the location where the two faces are in front with the plane
of symmetry in the center. The front position of needle structures with tips formed of four
faces is the location where the two faces with the largest area are in front with the plane of
symmetry in the center.
The geometric dimensions of the needle structures specified in this standard are height of
needle, H, widths at the bottom face of the needle structure, W and W , and distance, D ,
1 2 1
that is the dimension shown in the top view or side view in Figure 5.
_____________
1
 Numbers in square brackets refer to the Bibliography.
100 µm
100 µm

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SIST EN 62047-26:2016
– 10 – IEC 62047-26:2016 © IEC 2016
W
W
1
1
Top View
D
1
Top View
D
1
Front View Side View
Front View Side View
IEC
IEC


a) Typical needle structure with three faces b) Typical needle structure with four faces
Figure 5 – Front, side and top views of typical needle structures
Table 2 – Symbols and designations of needle structure in a micrometer scale
Symbol Unit Designation
W µm Horizontal width of needle structure at top view
1
W µm Vertical width of needle structure at top view
2
D µm Distance between tip and front point of needle structure
1
H
µm Height of needle structure

5.3 Description
Needle structures shall be dimensioned using Figure 5 in accordance with 5.1 and 5.2. See
[1]
ISO 129-1 for indicating dimensions.
6 Measurement method
See Annex A for examples of measurement for indicating the geometry of trench and needle
structures. The measurement conditions required for all measurements are described as
follows.
a) Record the temperature, humidity and necessary measurement conditions for each
measurement.
b) Perform measurement within the dimensional scale guaranteed in the instrument used for
each measurement.
c) Use instruments calibrated before each measurement.
d) For calibration of the instruments, consult the equipment supplier if necessary.
e) Maintain the levelness and perpendicularity of the sample when set in the instrument
within the range guaranteed in the instrument.
f) Specify the method of straight line approximation and curve approximation required for
indicating the geometry of trench structures.
g) The measurement results should be recorded in accordance with Clause B.2.
W
2
D
1
H

W
2
D
1
H

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SIST EN 62047-26:2016
IEC 62047-26:2016 ©
...

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