SIST EN IEC 62435-7:2021
(Main)Electronic components - Long-term storage of electronic semiconductor devices - Part 7: Microelectromechanical devices (IEC 62435-7:2020)
Electronic components - Long-term storage of electronic semiconductor devices - Part 7: Microelectromechanical devices (IEC 62435-7:2020)
IEC 62435-7:2020 on long-term storage applies to micro-electromechanical devices (MEMS) in long-term storage that can be used as part of obsolescence mitigation strategy. Long-term storage refers to a duration that may be more than 12 months for products scheduled for storage. Philosophy, good working practice, and general means to facilitate the successful long-term storage of electronic components are also addressed.
Elektronische Bauteile - Langzeitlagerung elektronischer Halbleiterbauelemente - Teil 7: Bauelemente der Mikrosystemtechnik (IEC 62435-7:2020)
Composants électroniques - Stockage de longue durée des dispositifs électroniques à semiconducteurs - Partie 7: Dispositifs microélectromécaniques (IEC 62435-7:2020)
L'IEC 62435-7:2020 relative au stockage de longue durée s’applique aux dispositifs microélectromécaniques (MEMS - micro-electromechanical device) du stockage de longue durée qui peuvent être utilisés dans le cadre d’une stratégie de réduction de l’obsolescence. Le stockage de longue durée implique une durée qui peut être supérieure à 12 mois, pour les produits destinés à être stockés. Les concepts, les bonnes pratiques professionnelles et les moyens généraux de nature à faciliter un stockage optimum de longue durée de composants électroniques sont aussi traités.
Elektronske komponente - Dolgoročno skladiščenje elektronskih polprevodniških elementov - 7. del: Mikroelektromehanski elementi (IEC 62435-7:2020)
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN IEC 62435-7:2021
01-marec-2021
Elektronske komponente - Dolgoročno skladiščenje elektronskih polprevodniških
elementov - 7. del: Mikroelektromehanski elementi (IEC 62435-7:2020)
Electronic components - Long-term storage of electronic semiconductor devices - Part 7:
Microelectromechanical devices (IEC 62435-7:2020)
Elektronische Bauteile - Langzeitlagerung elektronischer Halbleiterbauelemente - Teil 7:
Bauelemente der Mikrosystemtechnik (IEC 62435-7:2020)
Composants électroniques - Stockage de longue durée des dispositifs électroniques à
semiconducteurs - Partie 7: Dispositifs microélectromécaniques (IEC 62435-7:2020)
Ta slovenski standard je istoveten z: EN IEC 62435-7:2021
ICS:
31.080.01 Polprevodniški elementi Semiconductor devices in
(naprave) na splošno general
SIST EN IEC 62435-7:2021 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST EN IEC 62435-7:2021
---------------------- Page: 2 ----------------------
SIST EN IEC 62435-7:2021
EUROPEAN STANDARD EN IEC 62435-7
NORME EUROPÉENNE
EUROPÄISCHE NORM
January 2021
ICS 31.020
English Version
Electronic components - Long-term storage of electronic
semiconductor devices - Part 7: Micro-electromechanical
devices
(IEC 62435-7:2020)
Composants électroniques - Stockage de longue durée des Elektronische Bauteile - Langzeitlagerung elektronischer
dispositifs électroniques à semiconducteurs - Partie 7: Halbleiterbauelemente - Teil 7: Bauelemente der
Dispositifs microélectromécaniques Mikrosystemtechnik
(IEC 62435-7:2020) (IEC 62435-7:2020)
This European Standard was approved by CENELEC on 2021-01-08. 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, 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: Rue de la Science 23, B-1040 Brussels
© 2021 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 62435-7:2021 E
---------------------- Page: 3 ----------------------
SIST EN IEC 62435-7:2021
EN IEC 62435-7:2021 (E)
European foreword
The text of document 47/2664/FDIS, future edition 1 of IEC 62435-7, prepared by IEC/TC 47
"Semiconductor devices" was submitted to the IEC-CENELEC parallel vote and approved by
CENELEC as EN IEC 62435-7:2021.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2021-10-08
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2024-01-08
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 shall not be held responsible for identifying any or all such patent rights.
Endorsement notice
The text of the International Standard IEC 62435-7:2020 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:
IEC/TR 62258-3 NOTE Harmonized as CLC/TR 62258-3
2
---------------------- Page: 4 ----------------------
SIST EN IEC 62435-7:2021
EN IEC 62435-7:2021 (E)
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60721-3-1 - EN IEC 60721-3-1 -
Classification of environmental conditions
- Part 3-1: Classification of groups of
environmental parameters and their
severities - Storage
IEC 60749-20 - Semiconductor devices - Mechanical and EN IEC 60749-20 -
climatic test methods - Part 20:
Resistance of plastic encapsulated
SMDs to the combined effect of moisture
and soldering heat
IEC 60749-20-1 - Semiconductor devices - Mechanical and - -
climatic test methods - Part 20-1:
Handling, packing, labelling and shipping
of surface-mount devices sensitive to the
combined effect of moisture and
soldering heat
IEC 62435-2 - Electronic components - Long-term EN 62435-2 -
storage of electronic semiconductor
devices - Part 2: Deterioration
mechanisms
IEC 62435-3 - Electronic components - Long-term EN IEC 62435-3 -
storage of electronic semiconductor
devices - Part 3: Data
IEC 62435-4 - Electronic components - Long-term EN IEC 62435-4 -
storage of electronic semiconductor
devices - Part 4: Storage
IEC 62435-5 - Electronic components - Long-term EN 62435-5 -
storage of electronic semiconductor
devices - Part 5: Die and wafer devices
3
---------------------- Page: 5 ----------------------
SIST EN IEC 62435-7:2021
---------------------- Page: 6 ----------------------
SIST EN IEC 62435-7:2021
IEC 62435-7
®
Edition 1.0 2020-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electronic components – Long-term storage of electronic semiconductor
devices –
Part 7: Micro-electromechanical devices
Composants électroniques – Stockage de longue durée des dispositifs
électroniques à semiconducteurs –
Partie 7: Dispositifs microélectromécaniques
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.020 ISBN 978-2-8322-9147-4
Warning! Make sure that you obtained this publication from an authorized distributor.
Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale
---------------------- Page: 7 ----------------------
SIST EN IEC 62435-7:2021
– 2 – IEC 62435-7:2020 © IEC 2020
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Storage considerations . 9
4.1 Overview of MEMS applications . 9
4.2 Failure mechanisms . 9
4.2.1 Occurrence of failure and driving force . 9
4.2.2 Storage environment and mitigation for stimuli to prevent failure . 12
4.3 Materials management . 13
4.4 Storage media . 13
4.5 Documentation/paper lot identifiers . 14
4.6 Inventory check. 14
4.7 Inventory dry packing refreshing . 14
4.8 Inventory re-assessment . 14
5 Baseline long-term storage requirements . 14
5.1 General . 14
5.2 Moisture sensitivity designation . 15
5.3 Dry packing for storage . 15
5.4 Non-moisture sensitive device storage . 15
5.4.1 General . 15
5.4.2 Storage media . 15
5.4.3 Lot data and labelling . 15
5.5 Storage of MEMS devices before assembly – Wafer level and die level
storage . 15
5.6 Storage of moisture sensitive finished devices . 15
5.6.1 Moisture barrier bag . 15
5.6.2 Dunnage . 16
5.6.3 Humidity indicator card . 16
5.6.4 Desiccant . 16
5.6.5 Labelling . 16
5.6.6 Lot data and labelling . 16
5.6.7 Storage environment . 17
5.6.8 Process (temperature) sensitivity designation . 17
Annex A (informative) Packaged or finished device storage environment
considerations . 18
Bibliography . 19
Table 1 – Failure mechanisms in storage and stimuli to mitigate during storage . 10
Table 2 – Long-term environment – sustained condition requirements . 13
Table 3 – Considerations for management, control and documentation during storage . 13
Table A.1 – Long-term storage environment – sustained condition considerations . 18
---------------------- Page: 8 ----------------------
SIST EN IEC 62435-7:2021
IEC 62435-7:2020 © IEC 2020 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRONIC COMPONENTS – LONG-TERM STORAGE
OF ELECTRONIC SEMICONDUCTOR DEVICES –
Part 7: Micro-electromechanical devices
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 prepa-
ration 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 Stand-
ardization (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 inter-
ested 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 misinter-
pretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications trans-
parently 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 ex-
penses 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.
IEC 62435-7 has been prepared by IEC technical committee 47: Semiconductor devices. It is
an International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
47/2664/FDIS 47/2669/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
---------------------- Page: 9 ----------------------
SIST EN IEC 62435-7:2021
– 4 – IEC 62435-7:2020 © IEC 2020
A list of all parts in the IEC 62435 series, published under the general title Electronic
components – Long-term storage of electronic 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.
---------------------- Page: 10 ----------------------
SIST EN IEC 62435-7:2021
IEC 62435-7:2020 © IEC 2020 – 5 –
INTRODUCTION
This document applies to the long-term storage of electronic components.
This is a standard for long-term storage (LTS) of electronic devices drawing on the best long-
term storage practices currently known. For the purposes of this document, LTS is defined as
any device storage whose duration may be more than 12 months for product scheduled for long
duration storage. While intended to address the storage of unpackaged semiconductors and
packaged electronic devices, nothing in this document precludes the storage of other items
under the storage levels defined herein.
Although it has always existed to some extent, obsolescence of electronic components and
particularly of integrated circuits, has become increasingly intense over the last few years.
Indeed, with the existing technological boom, the commercial life of a component has become
very short compared with the life of industrial equipment such as that encountered in the
aeronautical field, the railway industry or the energy sector.
The many solutions enabling obsolescence to be resolved are now identified. However,
selecting one of these solutions should be preceded by a case-by-case technical and economic
feasibility study, depending on whether storage is envisaged for field service or production, for
example:
• remedial storage as soon as components are no longer marketed;
• preventive storage anticipating declaration of obsolescence.
Taking into account the expected life of some installations, sometimes covering several
decades, the qualification times, and the unavailability costs, which can also be very high, the
solution to be adopted to resolve obsolescence should often be rapidly implemented. This is
why the solution retained in most cases consists in systematically storing components which
are in the process of becoming obsolescent.
The technical risks of this solution are, a priori, fairly low. However, it requires perfect mastery
of the implemented process and especially of the storage environment, although this mastery
becomes critical when it comes to long-term storage.
All handling, protection, storage and test operations are recommended to be performed
according to the state of the art.
The application of the approach proposed in this document in no way guarantees that the stored
components are in perfect operating condition at the end of this storage. It only comprises a
means of minimizing potential and probable degradation factors.
Some electronic device users have the need to store electronic devices for long periods of time.
Lifetime buys are commonly made to support production runs of assemblies that well exceed
the production timeframe of their individual parts. This puts the user in a situation requiring
careful and adequate storage of such parts to maintain the as-received solderability and
minimize any degradation effects to the part over time. Major degradation concerns are moisture,
electrostatic fields, ultraviolet light, large variations in temperature, air-borne contaminants, and
outgassing.
---------------------- Page: 11 ----------------------
SIST EN IEC 62435-7:2021
– 6 – IEC 62435-7:2020 © IEC 2020
Warranties and sparing also present a challenge for the user or repair agency as some systems
have been designated to be used for long periods of time, in some cases for up to 40 years or
more. Some of the devices needed for repair of these systems will not be available from the
original supplier for the lifetime of the system or the spare assembly may be built with the
original production run but then require long-term storage This document was developed to
provide a standard for storing electronic devices for long periods of time. For storage of devices
that are moisture sensitive but that do not need to be stored for long periods of time, refer to
IEC TR 62258-3.
Long-term storage assumes that the device is going to be placed in uninterrupted storage for a
number of years. It is essential that it is useable after storage. Particular attention should be
paid to storage media surrounding the devices together with the local environment.
These guidelines do not imply any warranty of product or guarantee of operation beyond the
storage time given by the manufacturer.
The IEC 62435 series is intended to ensure that adequate reliability is achieved for devices in
user applications after long-term storage. Users are encouraged to request data from suppliers
to applicable specifications to demonstrate a successful storage life as requested by the user.
These standards are not intended to address built-in failure mechanisms that would take place
regardless of storage conditions.
These standards are intended to give practical guide to methods of long-duration storage of
electronic components where this is intentional or planned storage of product for a number of
years. Storage regimes for work-in-progress production are managed according to company
internal process requirements and are not detailed in this series of standards.
The overall standard series is split into a number of parts. Parts 1 to 4 apply to any long-term
storage and contain general requirements and guidance, whereas Parts 5 to 9 are specific to
the type of product being stored. It is intended that the product specific part should be read
alongside the general requirements of Part 1 to 4.
Electronic components requiring different storage conditions are covered separately starting
with Part 5.
The structure of the IEC 62435 series as currently conceived is as follows:
Part 1 – General
Part 2 – Deterioration mechanisms
Part 3 – Data
Part 4 – Storage
Part 5 – Die and wafer devices
Part 6 – Packaged or finished devices
Part 7 – Micro-electromechanical devices – MEMS
Part 8 – Passive electronic devices
Part 9 – Special cases
---------------------- Page: 12 ----------------------
SIST EN IEC 62435-7:2021
IEC 62435-7:2020 © IEC 2020 – 7 –
ELECTRONIC COMPONENTS – LONG-TERM STORAGE
OF ELECTRONIC SEMICONDUCTOR DEVICES –
Part 7: Micro-electromechanical devices
1 Scope
This part of IEC 62435 on long-term storage applies to micro-electromechanical devices (MEMS)
in long-term storage that can be used as part of obsolescence mitigation strategy. Long-term
storage refers to a duration that may be more than 12 months for products scheduled for storage.
Philosophy, good working practice, and general means to facilitate the successful long-term
storage of electronic components are also addressed.
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 60721-3-1, Classification of environmental conditions – Part 3-1: Classification of groups
of environmental parameters and their severities – Storage
IEC 60749-20, Semiconductor devices – Mechanical and climatic test methods – Part 20:
Resistance of plastic encapsulated SMDs to the combined effect of moisture and soldering heat
IEC 60749-20-1, Semiconductor devices – Mechanical and climatic test methods – Part 20-1:
Handling, packing, labelling and shipping of surface-mount devices sensitive to the combined
effect of moisture and soldering heat
IEC 62435-2, Electronic components – Long-term storage of electronic semiconductor devices
– Part 2: Deterioration mechanisms
IEC 62435-3, Electronic components – Long-term storage of electronic semiconductor devices
– Part 3: Data
IEC 62435-4, Electronic components – Long-term storage of electronic semiconductor devices
– Part 4: Storage
IEC 62435-5, Electronic components – Long-term storage of electronic semiconductor devices
– Part 5: Die and wafer devices
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
---------------------- Page: 13 ----------------------
SIST EN IEC 62435-7:2021
– 8 – IEC 62435-7:2020 © IEC 2020
3.1
storage environment
specially controlled storage area, with particular control of temperature, humidity, atmosphere
and any other conditions depending on the product requirements
3.2
critical moisture limit
maximum safe equilibrium moisture content for a specific encapsulated device at reflow assem-
bly or rework
3.3
long-term storage
LTS
planned storage of components to extend the life-cycle for a duration with the intention of sup-
porting future use
Note 1 to entry: Allowable storage durations will vary by product, form factor (e.g., packing materials, shape) and
storage conditions. In general, long-term storage is longer than 12 months.
3.4
LTS storeroom
area containing components that have additional packaging for storage to protect from moisture
or from mechanical impact or for ease of identification or handling
3.5
moisture-sensitive device
MSD
device that has moisture absorption or moisture retention and whose quality, process ability or
reliability is affected by moisture
3.6
electronic device
packaged electrical, electronic, electro-mechanical (EEE) item, or assemblies using such items
3.7
desiccant
hygroscopic substance used to remove moisture from an atmosphere
3.8
moisture barrier bag
MBB
storage bag manufactured with a flexible laminated vapour barrier film that restricts the trans-
mission of water vapour
Note 1 to entry: Refer to IEC 60749-20-1 for packaging of moisture sensitive products.
3.9
humidity indicator card
HIC
card printed with a moisture sensitive chemical that changes from blue to pink (colour) in the
presence of water vapour
3.10
water vapour transmission rate
WVTR
measure of permeability of MBBs to water vapour
---------------------- Page: 14 ----------------------
SIST EN IEC 62435-7:2021
IEC 62435-7:2020 © IEC 2020 – 9 –
3.11
dunnage
all the matter stored in a moisture barrier bag that is additional to the packaged electronic
component
3.12
electro-static discharge
ESD
transfer of electric charge between bodies of different electrostatic potentials in proximity or
through direct contact
[SOURCE: IEC 60050-561:2014, 561-03-06]
4 Storage considerations
4.1 Overview of MEMS applications
MEMS (Micro-electromechanical Systems) are miniaturized mechanical or electromechanical
elements that typically vary in size from 1 micron to 1 000 microns that are used to mechanically
measure or manipulate matter, light or create electric signals from environmental inputs.
Storage of MEMS devices should consider different sensitivities and risks compared to other
semiconductor devices due to the mechanical nature of the devices. MEMS may be subject to
additional mechanical related performance and failure mechanisms in addition traditional
semiconductor performance mechanisms. The storage program should consider the end use
and failure mechanisms related to the function of the MEMS device. Typical uses are listed for
initial consideration and risk assessment.
– Actuator mechanical movement related to electrostatics, thermal changes or piezoelectric
effects.
– Physical sensors related to acceleration, vibration, field/flux, force, magnetic field, electro-
static, optical stimulus or radiation effects, pressure, temperature.
– Chemisensors related to gas or liquid induced mechanical response changes (may also
have requirements for moisture or solvent which also have shelf life).
– Biosensors liquid, mechanical or fluidic induced mechanical response changes (may also
have requirements for moisture or solvent which also have shelf life).
4.2 Failure mechanisms
4.2.1 Occurrence of failure and driving force
Failures during long-term storage may be mitigated by control of the stimuli driving given failure
modes of interest as defined by risk assessment tools, for example, failure modes and effects
analysis (FMEA). Storage related failures
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.