SIST EN IEC 62435-6:2019
(Main)Electronic components - Long-term storage of electronic semiconductor devices - Part 6: Packaged or Finished Devices (IEC 62435-6:2018)
Electronic components - Long-term storage of electronic semiconductor devices - Part 6: Packaged or Finished Devices (IEC 62435-6:2018)
This part of IEC 62435 on long-term storage applies to packaged or finished devices in longterm
storage that can be used as part of obsolescence mitigation strategy. Long-term storage
refers to a duration that can be more than 12 months for product 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 6: Bauelemente in Gehäusen oder fertiggestellte Bauelemente
Composants électroniques - Stockage de longue durée des dispositifs électroniques à semiconducteurs - Partie 6: Dispositifs encapsulés ou finis
L’IEC 62435-6:2018 portant sur le stockage de longue durée s’applique aux dispositifs encapsulés ou finis en stockage de longue durée qui peuvent être utilisés dans le cadre d’une stratégie de réduction de l’obsolescence. Le stockage de longue durée fait référence à une durée qui peut être supérieure à 12 mois, pour un produit destiné à être stocké. Les concepts, les bonnes pratiques et les moyens généraux de nature à faciliter la réussite d’un stockage de longue durée de composants électroniques sont aussi abordés.
Elektronske komponente - Dolgoročno skladiščenje elektronskih polprevodniških elementov - 6. del: Pakirani ali končni elementi (IEC 62435-6:2018)
Ta del standarda IEC 62435 o dolgoročnem skladiščenju se uporablja za dolgoročno skladiščene pakirane ali končne naprave, ki se lahko uporabljajo kot del strategije za ublažitev zastarelosti. Dolgoročno skladiščenje se nanaša na obdobje, ki je lahko daljše od 12 mesecev, za izdelke, namenjene za skladiščenje. Obravnavana so tudi načela, dobra delovna praksa in splošna sredstva za lažjo uspešno dolgoročno skladiščenje elektronskih komponent.
General Information
Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.SUHYRGQLãNLKElectronic components - Long-term storage of electronic semiconductor devices - Part 6: Packaged or Finished Devices (IEC 62435-6:2018)31.080.01Polprevodniški elementi (naprave) na splošnoSemiconductor devices in generalICS:Ta slovenski standard je istoveten z:EN IEC 62435-6:2018SIST EN IEC 62435-6:2019en01-januar-2019SIST EN IEC 62435-6:2019SLOVENSKI
STANDARD
SIST EN IEC 62435-6:2019
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN IEC 62435-6
October 2018 ICS 31.020
English Version
Electronic components - Long-term storage of electronic semiconductor devices - Part 6: Packaged or finished devices (IEC 62435-6:2018)
Composants électroniques - Stockage de longue durée des dispositifs électroniques à semiconducteurs - Partie 6: Dispositifs encapsulés ou finis (IEC 62435-6:2018)
Elektronische Bauteile - Langzeitlagerung elektronischer Halbleiterbauelemente - Teil 6: Bauelemente in Gehäusen oder fertiggestellte Bauelemente (IEC 62435-6:2018) This European Standard was approved by CENELEC on 2018-10-03. 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: Rue de la Science 23,
B-1040 Brussels © 2018 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 62435-6:2018 E SIST EN IEC 62435-6:2019
EN IEC 62435-6:2018 (E) 2 European foreword The text of document 47/2482/FDIS, future edition 1 of IEC 62435-6, prepared by IEC/TC 47 "Semiconductor devices" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as EN IEC 62435-6:2018. The following dates are fixed: • latest date by which the document has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2019-07-03 • latest date by which the national standards conflicting with the document have to be withdrawn (dow) 2021-10-03 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 62435-6:2018 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 60721-3-1 NOTE Harmonized as EN IEC 60721-3-1 IEC 62435-1 NOTE Harmonized as EN 62435-1 IEC 62435-2 NOTE Harmonized as EN 62435-2 IEC 62435-31 NOTE Harmonized as EN IEC 62435-32
IEC 62435-4 NOTE Harmonized as EN IEC 62435-4 IEC 62435-5 NOTE Harmonized as EN 62435-5 IEC 62435-73 NOTE Harmonized as EN IEC 62435-74 IEC 62435-85 NOTE Harmonized as EN IEC 62435-86
1 Under preparation. Stage at the time of publication: IEC/CCDV 62435-3:2018. 2 Under preparation. Stage at the time of publication: prEN IEC 62435-3:2018. 3 Under preparation. Stage at the time of publication: IEC/CD 62435-7:2018. 4 Under preparation. Stage at the time of publication: prEN IEC 62435-7:2018. 5 Under preparation. Stage at the time of publication: IEC/CD 62435-8:2018. 6 Under preparation. Stage at the time of publication: prEN IEC 62435-8:2018. SIST EN IEC 62435-6:2019
EN IEC 62435-6:2018 (E) 3 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 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 EN 60749-20 -
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 EN 60749-20-1 -
JEDEC J-STD-020 -
Moisture/reflow classification for nonhermetic solid state surface mount devices - -
JEDEC J-STD-075 -
Classification of non-IC electronic components for assembly processes - -
SIST EN IEC 62435-6:2019
SIST EN IEC 62435-6:2019
IEC 62435-6 Edition 1.0 2018-08 INTERNATIONAL STANDARD NORME INTERNATIONALE Electronic components – Long-term storage of electronic semiconductor devices – Part 6: Packaged or finished devices
Composants électroniques – Stockage de longue durée des dispositifs électroniques à semiconducteurs – Partie 6: Dispositifs encapsulés ou finis
INTERNATIONAL ELECTROTECHNICAL COMMISSION COMMISSION ELECTROTECHNIQUE INTERNATIONALE
ICS 31.020
ISBN 978-2-8322-5979-5
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale ®
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. SIST EN IEC 62435-6:2019
– 2 – IEC 62435-6:2018 © IEC 2018 CONTENTS FOREWORD . 3 INTRODUCTION . 5 1 Scope . 7 2 Normative references . 7 3 Terms and definitions . 7 4 Storage considerations . 9 4.1 Failure mechanisms . 9 4.1.1 Occurrence of failure and driving force . 9 4.1.2 Storage environment and mitigation for stimuli to prevent failure . 10 4.2 Materials management . 11 4.3 Storage media . 11 4.4 Inventory check. 11 4.5 Inventory dry packing refreshing . 12 4.6 Inventory re-assessment . 12 5 Baseline long-term storage requirements . 12 5.1 General . 12 5.1.1 Categories . 12 5.1.2 Critical aspects . 12 5.1.3 Recommendations and best practice . 12 5.2 Non-moisture sensitive device storage . 13 5.2.1 Storage media . 13 5.2.2 Lot data and labelling . 13 5.3 Moisture sensitive finished device storage . 13 5.3.1 Moisture sensitivity designation . 13 5.3.2 Dry packing for storage . 13 5.3.3 Moisture barrier bag . 13 5.3.4 Dunnage . 13 5.3.5 Humidity indicator card – HIC . 14 5.3.6 Desiccant . 14 5.3.7 Labelling . 14 5.4 Storage environment . 14 5.5 Process (temperature) sensitivity designation . 14 Annex A (informative)
Packaged or finished device storage environment considerations . 15 Bibliography . 16
Table 1 – Example failure mechanisms in storage and stimuli to mitigate during storage . 9 Table 2 – Long-term environment – Sustained condition requirements . 10 Table 3 – Considerations for management, control and documentation during storage . 11 Table A.1 – Long-term storage environment – Sustained condition considerations . 15
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INTERNATIONAL ELECTROTECHNICAL COMMISSION ____________
ELECTRONIC COMPONENTS – LONG-TERM STORAGE OF ELECTRONIC SEMICONDUCTOR DEVICES –
Part 6: Packaged or finished 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 interna-tional 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, Tech-nical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publica-tion(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 Interna-tional 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 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 transparently to the maximum extent possible in their national and regional publications. Any divergence be-tween 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 Publica-tions.
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 62435-6 has been prepared by IEC technical committee 47: Semi-conductor devices. The text of this International Standard is based on the following documents: FDIS Report on voting 47/2482/FDIS 47/2495/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. SIST EN IEC 62435-6:2019
– 4 – IEC 62435-6:2018 © IEC 2018 A list of all parts in the IEC 62435 series, published under the general title Electronic compo-nents – 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-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 standard, LTS is defined as any device storage whose duration can 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 aer-onautical field, the railway industry or the energy sector. The many solutions enabling obsolescence to be resolved are now identified. However, se-lecting 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 dec-ades, 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 ac-cording 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 com-prises 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 re-quiring 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 con-taminants, and outgassing. Warranties and sparing also present a challenge for the user or repair agency as some sys-tems 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 availa-ble from the original component manufacturer for the lifetime of the system or the spare as-sembly can be built with the original production run but then requires long-term storage. This document was developed to provide a standard for storing electronic devices for long periods SIST EN IEC 62435-6:2019
– 6 – IEC 62435-6:2018 © IEC 2018 of time. For storage of devices that are moisture sensitive but that do not need to be stored for long periods of time, IEC TR 62258-3 can be consulted. 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 component 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 suppli-ers 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 is split into a number of parts. Parts 1 to 4 apply to any long-term stor-age and contain general requirements and guidance, whereas Parts 5 to 9 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 planned to be covered sepa-rately 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
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ELECTRONIC COMPONENTS – LONG-TERM STORAGE OF ELECTRONIC SEMICONDUCTOR DEVICES –
Part 6: Packaged or finished devices
1 Scope This part of IEC 62435 on long-term storage applies to packaged or finished devices in long-term storage that can be used as part of obsolescence mitigation strategy. Long-term storage refers to a duration that can be more than 12 months for product scheduled for storage. Phi-losophy, good working practice, and general means to facilitate the successful long-term stor-age 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 con-tent 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 60749-20, Semiconductor devices – Mechanical and climatic test methods – Part 20: Re-sistance 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 JEDEC J-STD-020, Moisture/reflow classification for nonhermetic solid state surface mount devices JEDEC J-STD-075, Classification of non-IC electronic components for assembly processes 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 ad-dresses: • IEC Electropedia: available at http://www.electropedia.org/ • ISO Online browsing platform: available at http://www.iso.org/obp 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 as-sembly or rework SIST EN IEC 62435-6:2019
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long-term storage LTS planned storage of components to extend the life-cycle for a duration with the intention of supporting future use Note 1 to entry: Allowable storage durations will vary by form factor (for example; 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 mois-ture 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 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 transmission 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, typically,
from blue to pink in the presence of water vapour 3.10
water vapour transmission rate
WVTR measure of permeability of MBBs to water vapour 3.11
dunnage all the matter stored in a moisture barrier bag that is additional to the packaged electronic component 3.12
electrostatic discharge ESD transfer of electric charge between bodies of different electrostatic potentials in proximity or through direct contact
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[SOURCE: IEC 60050-561:2014, 561-03-06] 4 Storage considerations 4.1 Failure mechanisms 4.1.1 Occurrence of failure and driving force Failures during long-term storage may be mitigated by control of the stimuli and driving forces likely to initiate given failure modes of interest as defined by a Failure Modes and Effects Analysis (FMEA). Storage related failures are often detected as modes of non-operation, vis-ual quality or other non-conformance. The modes of failure during storage are typically related to a failure mechanism that is driven by a physical stimuli or condition. Successful long-term storage is accomplished by controlling the failure mechanism stimuli as identified using a fail-ure modes and effect analysis based on information from technology development and test-ing. Table 1 provides examples of failure stimuli. Additional examples of deterioration mecha-nisms are found in IEC 62435-2. Successful long-term storage is accomplished by mitigating failures through control of the stimuli or driving force. Table 1 – Example failure mechanisms in storage and stimuli to mitigate during storage Failure mechanism Failure mechanism detail Failure mode
Mechanism stimuli Popcorn effect High rate vapour expansion within a package during sur-face mounting Open circuit, blistering, package cracks Temperature increase leading to moisture vapour Handling damage Cracking Open, short, visible crack Application of force Visible scratch/smudge Open, short, surface mark Mechanical abrasion Device data loss/damage Electro-magnetic current field induced short/open/error Open, short, data corrup-tion Electro-magnetic field High ionizing radiation in-duced open, short or error Open, short, data corrup-tion High-energy radiation, x-ray Soft error resulting from device damage Open, short or data cor-ruption Neutron particle hit Alpha particle emission hit Staining residue Change in surface appear-ance and specification re-sulting from unplanned ex-posure to oxidizing contents Visible defect, non-conforming appearance and potential of mispro-cessing Exposure resulting in aging, oxida-tion or hardening of residue Polymer material aging Polymer embrittlement Visible cracking, open or shorting Temperature exposure, residual mechanical stress and bright light Storage media
issues Tape on reel, tube embrit-tlement/aging Misalignment during pro-cessing Temperature exposure, mechanical stressing and bright light Tray and tube aging embrit-tlement Dropped parts from broken tray media or parts out of formed pocket Temperature, handling and bright light Box aging embrittlement Dropped parts Opens or shorts from ESD Foreign material Temperature and bright light ESD coating degradations Opens or shorts from ESD Triboelectric charging or charge potential difference Label aging Illegible mark Bright light, temperature Missing label Temperature and bright light Brittle flaking – partial label Temperature and bright light SIST EN IEC 62435-6:2019
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Mechanism stimuli Indirect material issues Moisture barrier bag leak Humidity indicator card trigger, visual non-conformance Handling abrasion, bending and shock events Humidity Indicator Card In-activated Incorrect colour or no moisture exposure indicat-ed Temperature, humidity Exposure before use Label aging Illegible mark Bright light, temperature Missing label Temperature and bright light Brittle flaking – partial label Temperature and bright light Solderability Inability to form a good sol-der joint Post surface mount elec-trical open Temperature, humidity Exposure Corrosion Electro-chemical reaction leading failure Open, short, visual non-conformance Temperature, galvanic cell, chemi-cal residue Tin
whiskers Whisker filament formed by dislocations in metal films with a gradient in surface mechanical stress. Visual whiskers, short Bright tin(Sn) surface finish (un-alloyed) crystal dislocation growth (in un-mitigated parts) Sulphur gas catalysed reaction Wettability Passivation surface change Flux or adhesion change Surface energy change 4.1.2 Storage environment and mitigation for stimuli to prevent failure Mitigation of failures during and after long-term storage occurs by directly controlling or limit-ing the stimulus for failure by a number of means. Common requirements for sustained long-term storage are given in Table 2. Knowledge
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