SIST EN 62435-5:2017
(Main)Electronic components - Long-term storage of electronic semiconductor devices - Part 5: Die and wafer devices (IEC 62435-5:2017)
Electronic components - Long-term storage of electronic semiconductor devices - Part 5: Die and wafer devices (IEC 62435-5:2017)
This part of IEC 62435, is applicable to long-term storage of die and wafer devices and
establishes specific storage regimen and conditions for singulated bare die and partial or
complete wafers of die including die with added structures such as redistribution layers and
solder balls or bumps or other metallisation. This part also provides guidelines for special
requirements and primary packaging that contain the die or wafers for handling purposes.
Typically, this part is used in conjunction with IEC 62435-1 for long-term storage of devices
whose duration can be more than 12 months for products scheduled for long duration storage.
Elektronische Bauteile - Langzeitlagerung elektronischer Halbleiterbauelemente - Teil 5: Chip- und Wafererzeugnisse
Composants électroniques - Stockage de longue durée des dispositifs électroniques à semiconducteurs - Partie 5: Dispositifs de puces et plaquettes
L’IEC 62435-5:2017 est applicable au stockage de longue durée des dispositifs de puces et plaquettes et établit le régime et les conditions de stockage pour les puces nues singularisées et les plaquettes partielles ou complètes de puces incluant les puces avec ajout de structures telles que des couches de redistribution et des billes ou des perles de soudure ou d’autres métallisations. La présente partie donne également des lignes directrices pour les exigences spéciales et l’encapsulation primaire destinée à contenir la puce ou les plaquettes à des fins de manipulation. Elle s’utilise habituellement conjointement avec l'IEC 62435-1:2017 pour tout stockage de longue durée de dispositifs dont la durée peut être supérieure à 12 mois, pour un produit destiné à être stocké pendant une durée prolongée.
Elektronske komponente - Dolgoročno skladiščenje elektronskih polprevodniških elementov - 5. del: Elementi na čipih in rezinah (IEC 62435-5:2017)
Ta del standarda IEC 62435 se uporablja za dolgoročno skladiščenje elementov na čipih in rezinah ter določa poseben režim skladiščenja in pogoje za singularne čipe brez ohišja in delne ali celotne rezine čipov, vključno s čipi z dodanimi strukturami, kot so prerazporeditveni sloji in kroglice ali izbokline oz. druga metalizacija. Ta del zagotavlja tudi smernice za posebne zahteve in primarno embalažo, ki vsebuje čipe ali rezine, za namene ravnanja z njimi. Običajno se ta del uporablja skupaj s standardom IEC 62435-1 za dolgoročno skladiščenje poljubne naprave, ki je lahko daljše od 12 mesecev za izdelke, ki so načrtovani za dolgoročno skladiščenje.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 62435-5:2017
01-junij-2017
(OHNWURQVNHNRPSRQHQWH'ROJRURþQRVNODGLãþHQMHHOHNWURQVNLKSROSUHYRGQLãNLK
HOHPHQWRYGHO (OHPHQWLQDþLSLKLQUH]LQDK ,(&
Electronic components - Long-term storage of electronic semiconductor devices - Part 5:
Die and wafer devices (IEC 62435-5:2017)
Composants électroniques - Stockage de longue durée des dispositifs électroniques à
semiconducteurs - Partie 5: Dispositifs de puces et plaquettes
Ta slovenski standard je istoveten z: EN 62435-5:2017
ICS:
31.080.01 Polprevodniški elementi Semiconductor devices in
(naprave) na splošno general
SIST EN 62435-5:2017 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 62435-5:2017
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SIST EN 62435-5:2017
EUROPEAN STANDARD EN 62435-5
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2017
ICS 31.020
English Version
Electronic components - Long-term storage of electronic
semiconductor devices - Part 5: Die and wafer devices
(IEC 62435-5:2017)
Composants électroniques - Stockage de longue durée des Elektronische Bauteile - Langzeitlagerung elektronischer
dispositifs électroniques à semiconducteurs - Halbleiterbauelemente - Teil 5: Chip- und Wafererzeugnisse
Partie 5: Dispositifs de puces et plaquettes (IEC 62435-5:2017)
(IEC 62435-5:2017)
This European Standard was approved by CENELEC on 2017-02-24. 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, 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: Avenue Marnix 17, B-1000 Brussels
© 2017 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN 62435-5:2017 E
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SIST EN 62435-5:2017
EN 62435-5:2017
European foreword
The text of document 47/2328/FDIS, future edition 1 of IEC 62435-5, prepared by
IEC/TC 47 "Semiconductor devices" was submitted to the IEC-CENELEC parallel vote and approved
by CENELEC as EN 62435-5:2017.
The following dates are fixed:
(dop) 2017-11-24
• latest date by which the document has to be
implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2020-02-24
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 62435-5:2017 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 60068-2-17 NOTE Harmonized as EN 60068-2-17.
IEC 60068-2-20 NOTE Harmonized as EN 60068-2-20.
IEC 60749-3 NOTE Harmonized as EN 60749-3.
IEC 60749-20-1 NOTE Harmonized as EN 60749-20-1.
IEC 60749-21 NOTE Harmonized as EN 60749-21.
IEC 60749-22 NOTE Harmonized as EN 60749-22.
IEC 61340-5-1 NOTE Harmonized as EN 61340-5-1.
IEC 61340-2-1 NOTE Harmonized as EN 61340-2-1.
IEC/TR 62258-3 NOTE Harmonized as CLC/TR 62258-3.
IEC 62435-1 NOTE Harmonized as EN 62435-1.
2
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SIST EN 62435-5:2017
EN 62435-5:2017
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1 When 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 62435-2 - Electronic components - Long-term EN 62435-2 -
storage of electronic semiconductor
devices -
Part 2: Deterioration mechanisms
3
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SIST EN 62435-5:2017
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SIST EN 62435-5:2017
IEC 62435-5
®
Edition 1.0 2017-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Electronic components – Long-term storage of electronic semiconductor
devices –
Part 5: Die and wafer devices
Composants électroniques – Stockage de longue durée des dispositifs
électroniques à semiconducteurs –
Partie 5: Dispositifs de puces et plaquettes
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.020 ISBN 978-2-8322-3837-0
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
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SIST EN 62435-5:2017
– 2 – IEC 62435-5:2017 © IEC 2017
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 8
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 8
3.1 Terms and definitions . 8
3.2 Abbreviations . 9
4 Storage requirements . 9
4.1 General . 9
4.2 Assembly data . 9
4.3 Prerequisite for storage. 9
4.4 Damage to die products during long-term storage . 9
4.5 Mechanical storage conditions . 10
4.6 Long-term storage environment . 10
4.7 Recommended inert atmosphere purity . 11
4.8 Chemical contamination . 11
4.9 Vacuum packing . 11
4.9.1 General . 11
4.9.2 Vacuum dry pack . 11
4.10 Positive pressure systems for packing . 11
4.11 Use of packing material having sacrificial properties . 11
4.12 Use of bio-degradable material . 12
4.13 Plasma cleaning . 12
4.14 Electrical effects . 12
4.15 Protection from radiation . 12
4.16 Periodic qualification of stored die products . 12
5 Long-term storage failure mechanisms . 13
6 LTS concerns, method, verification and limitations . 13
6.1 General . 13
6.2 Wafers . 13
6.3 Bare dice . 14
7 Deterioration mechanisms specific to bare die and wafers . 15
7.1 Wire bondability . 15
7.2 Staining . 15
7.3 Topside delamination . 16
8 Specific handling concerns . 16
8.1 Die on wafer film frames . 16
8.2 Devices and dice embossed or punched tape storage . 16
8.3 Handling damage . 16
Annex A (informative) Audit checklist . 17
Bibliography . 20
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IEC 62435-5:2017 © IEC 2017 – 3 –
Table 1 – LTS exposure concerns for wafers . 14
Table 2 – LTS exposure concerns for bare dice . 15
Table A.1 – Planning checklist . 17
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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTRONIC COMPONENTS – LONG-TERM STORAGE
OF ELECTRONIC SEMICONDUCTOR DEVICES –
Part 5: Die and wafer 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 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 62435-5 has been prepared by IEC technical committee 47:
Semiconductor devices.
The text of this standard is based on the following documents:
FDIS Report on voting
47/2328/FDIS 47/2351/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.
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SIST EN 62435-5:2017
IEC 62435-5:2017 © IEC 2017 – 5 –
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.
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INTRODUCTION
This document applies to the long-duration storage of electronic components.
This is a document 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 standard 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 its 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, ultra-violet light, large variations in temperature, air-borne
contaminants, and outgassing.
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.
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IEC 62435-5:2017 © IEC 2017 – 7 –
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 original device 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 these 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-term 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 IEC 62345 series includes a number of parts. Parts 1 to 4 apply to any long-term storage
1
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 Parts 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 – MEMS
Part 8 – Passive electronic devices
Part 9 – Special cases
______________
1
Under preparation.
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ELECTRONIC COMPONENTS – LONG-TERM STORAGE
OF ELECTRONIC SEMICONDUCTOR DEVICES –
Part 5: Die and wafer devices
1 Scope
This part of IEC 62435, is applicable to long-term storage of die and wafer devices and
establishes specific storage regimen and conditions for singulated bare die and partial or
complete wafers of die including die with added structures such as redistribution layers and
solder balls or bumps or other metallisation. This part also provides guidelines for special
requirements and primary packaging that contain the die or wafers for handling purposes.
Typically, this part is used in conjunction with IEC 62435-1 for long-term storage of devices
whose duration can be more than 12 months for products scheduled for long duration storage.
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 62435-2, Electronic components – long-term storage of electronic semiconductor devices
– Part 2: Deterioration mechanisms
3 Terms, definitions and abbreviated terms
For the purposes of this document, the following terms, definitions and abbreviated terms
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 Terms and definitions
3.1.1
storage environment
specially controlled storage area, with particular control of temperature, humidity, atmosphere
and any other conditions depending on the product requirements
3.1.2
long-term storage
LTS
planned storage of components to extend the life-cycle for a duration with the intention of
supporting future use
3.1.3
desiccant
hygroscopic substance used to remove moisture from an atmosphere
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IEC 62435-5:2017 © IEC 2017 – 9 –
3.2 Abbreviations
MEMS microelectromechanical systems
rH relative humidity
ESD electro-static discharge
EMR electromagnetic radiation
RF radio frequency
MBB moisture barrier bag
HIC humidity indicator card
V voltage threshold
T
QSS surface state charge
I current off
OFF
V voltage off
OFF
VCI volatile corrosion inhibitors
ILD inter-layer dielectric
4 Storage requirements
4.1 General
This clause details requirements for storage of dies and wafers including specific
environmental options. The required environment and control for any product shall be
determined according to the exposure concern detailed in Tables 1 and 2.
For example, if oxygen is determined to be a possible concern for degradation of product over
the expected length of storage, then a storage environment should be selected that best
reduces the risk of long-term exposure to oxygen during storage.
This section details the different storage options commonly available.
4.2 Assembly data
Care should be taken that data or information required for subsequent processing of the
product, such as wafer maps, is useable after storage.
4.3 Prerequisite for storage
Only a product with a known status, including quality and functionality, shall be stored. If in
wafer form, the wafer should be inked or a wafer map should be stored in a way that can be
used at the end of LTS. Be aware that wafer maps on electronic media may not be retrievable
at the end of the storage period and backup methods should be periodically reviewed. It
should be noted that ink may also be a potential source of contamination and may require
evaluation for LTS.
Where initial 100 % test of the wafer cannot be performed, an alternative method shall be
used to determine the overall quality and functionality of the product to be stored. This may
include sample testing or qualification of an assembled sample of product representative of
the wafers being stored.
4.4 Damage to die products during long-term storage
Defects caused by mechanical damage may affect different regions of the die or wafer and
should be considered when designing long-term storage schemes.
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4.5 Mechanical storage conditions
In order to ensure adequate mechanical protection for die and wafers, care shall be taken in
the initial placement of products in storage containers and removal from these containers
after storage. Damage can easily occur during loading and unloading.
During storage, sufficient protection shall be given to the product to guard against movement
or vibration. Die or wafer orientation can be important, especially for MEMS or sensor
products, to minimize damage due to shock or vibration. Containers and shelving may require
anti-vibration or anti-resonance mounting. Packing material should be designed to offer some
degree of protection against shock or vibration.
Die and wafers shall not be inspected unless required under a specific sample programme in
order to minimize the amount of handling to which the die or wafers are subjected.
Material in contact with the wafer or die surface shall ensure that there is minimal abrasion
and adhesion of foreign matter to surfaces.
4.6 Long-term storage environment
These conditions are more stringent than those for short-term storage since the storage
environment is critical to successful long-term storage. Packing methods suggested here may
not be suitable for shipping, especially by air transportation.
This storage atmosphere is designed to exclude oxygen and limit humidity which are known
deterioration sources for unencapsulated semiconductor devices. Actual failure mechanisms
shall be determined according to the device being stored with reference to IEC 62435-2.
Cabinets or containers for long-term storage of die or wafers shall use the following conditions:
a) purge gas: 99 % nitrogen or inert gas (see 4.7);
b) temperature: 17 °C to 25 °C;
c) cabinet humidity: rH minimum of 7 %, maximum of 25 %;
d) pressure: slightly above ambient atmospheric pressure.
The gas pressure should be sufficiently high to prevent the ingress of external contaminants.
To control the relative humidity, it is normal for die and wafer storage environments to use
high-purity nitrogen, for example, derived from a liquid source.
Relative humidity should not fall below 7 % in order to prevent build-up of electrostatic fields
and should not exceed 25 % in order to prevent condensation and moisture ingress. This is
important after a storage cabinet has been opened; it is normal to fit a timed purge regulator
to rapidly bring the relati
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