1、DRAFT FOR DEVELOPMENTDD IEC/PAS 62435:2005Electronic components Long-duration storage of electronic components Guidance for implementationICS 31.020g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39
2、g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58DD IEC/PAS 62435:2005This Draft for Development was published under the authority of the Standards Policy and Strategy Committee on 30 January 2006 BSI 30 January 2006ISBN 0 580 47632 4National forewordThis Draft for Development reproduces verbatim IEC
3、/PAS 62435:2005.This publication is not to be regarded as a British Standard. A PAS is a Technical Specification not fulfilling the requirements for a standard, but made available to the public and established in an organization operating under a given procedure.It is being issued in the Draft for D
4、evelopment series of publications and is of a provisional nature because it is still under development and, with insufficient data as yet to relate it to experience in the field, it may be subject to significant change. It should be applied on this provisional basis, so that information and experien
5、ce of its practical application may be obtained.Comments arising from the use of this Draft for Development are requested so that UK experience can be reported to the international organization responsible for the Technical Specification. A review of this publication will be initiated not later than
6、 3 years after its publication by the international organization so that a decision can be taken on its status at the end of its 3-year life. Notification of the start of the review period will be made in an announcement in the appropriate issue of Update Standards.According to the replies received
7、by the end of the review period, the responsible BSI Committee will decide whether to support the conversion into an international standard, to extend the life of the Technical Specification for another 3 years or to withdraw it. Comments should be sent in writing to the Secretary of BSI Technical C
8、ommittee EPL/47, Semiconductors, at British Standards House, 389 Chiswick High Road, London W4 4AL, giving the document reference and clause number and proposing, where possible, an appropriate revision of the text.A list of organizations represented on this committee can be obtained on request to i
9、ts secretary. Cross-referencesThe British Standards which implement international publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue o
10、r of British Standards Online.This publication does not purport to incldue all the necessary provisions of a contract. Users are responsible for its correct application.Summary of pagesThis document comprises a front cover, an inside front cover, the IEC/PAS title page, pages 2 to 30, an inside back
11、 cover and a back cover.The BSI copyright date displayed in this document indicates when the document was last issued.Amendments issued since publicationAmd. No. Date CommentsPUBLICLY AVAILABLE SPECIFICATIONIECPAS 62435Pre-Standard First edition2005-09Electronic components Long-duration storage of e
12、lectronic components Guidance for implementation PRICE CODE IEC 2005 Copyright - all rights reserved No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher
13、. International Electrotechnical Commission, 3, rue de Varemb, PO Box 131, CH-1211 Geneva 20, SwitzerlandTelephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmailiec.ch Web: www.iec.ch U For price, see current catalogue Commission Electrotechnique InternationaleInternational Electrotechni
14、cal Commission DD IEC/PAS 62435:2005 2 CONTENTS FOREWORD.4 INTRODUCTION.5 1 Scope 6 2 Normative references .6 3 Storage decision criteria .6 3.1 Advantages .7 3.1.1 Technical simplicity Rapidity7 3.1.2 Solution durability 7 3.1.3 Preventive storage .7 3.2 Hazards Drawbacks7 3.2.1 Generic aging hazar
15、d.7 3.2.2 Poor stock dimensioning 7 3.2.3 Incorrect control of reliability during storage .8 3.2.4 Freezing equipment functionalities .8 3.3 Storage cost .8 3.4 Decision criteria.8 4 Purchasing Procurement9 4.1 List of components 9 4.2 Quantity of components to be stored 9 4.2.1 Production stock 9 4
16、.2.2 Field service stock .9 4.3 When is it worth keeping in stock? .10 4.4 Procurement recommendations10 5 Technical validation of the components.10 5.1 Purpose 10 5.2 Relevant field 10 5.3 Test selection criteria 11 5.4 Measurements and tests11 5.4.1 Sampling .11 5.4.2 Visual examination, sealing,
17、solderability11 5.4.3 Compliance with the electrical specifications 12 5.4.4 Assessment of the supplied batch reliability13 5.4.5 Manufacturing control check (technological analysis) 15 5.5 Sanction15 6 Conditioning and storage 15 6.1 Type of environment 15 6.2 Elementary storage unit.16 6.3 Stock m
18、anagement16 6.4 Redundancy 16 6.5 Identification Traceability 16 6.6 Initial packaging 16 6.7 Stabilization bake 17 6.8 Storage conditions.17 6.8.1 Storage area17 6.8.2 Temperature 17 DD IEC/PAS 62435:2005 3 6.8.3 Temperature variations 17 6.8.4 Relative humidity Chemical attacks Contamination17 6.8
19、.5 Pressure17 6.8.6 Electrostatic discharges .17 6.8.7 Vibration Mechanical impacts 18 6.8.8 Electromagnetic field Radiation .18 6.8.9 Light 18 6.9 Maintaining storage conditions.18 7 Periodic check of the components.18 7.1 Objectives .18 7.2 Periodicity .19 7.3 Tests during periodic check .19 8 Des
20、tocking .19 8.1 Precautions .19 8.1.1 Electrostatic discharges .19 8.1.2 Mechanical impacts19 8.2 Inspection .19 9 Feedback .20 Annex A (informative) Example of a component list .21 Annex B (informative) Examples of periodic and/or destocking tests (1/3) 23 Annex C (informative) Parameters influenci
21、ng the final price of the component storage .25 Annex D (informative) Parameters influencing the quantity of components to be stored .26 Annex E (normative) Failure mechanisms: Encapsulated and non-encapsulated active components27 Annex F (normative) Failure mechanisms: GaAs components.29 DD IEC/PAS
22、 62435:2005 4 INTERNATIONAL ELECTROTECHNICAL COMMISSION _ ELECTRONIC COMPONENTS Long-duration storage of electronic components Guidance for implementation FOREWORD 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrote
23、chnical 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 Specificatio
24、ns, 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,
25、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 decisi
26、ons 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 interna
27、tional 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 orde
28、r 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 clea
29、rly indicated in the latter. 5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any equipment declared to be in conformity with an IEC Publication. 6) All users should ensure that they have the latest edition of this publication. 7) No liability shal
30、l 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 lega
31、l 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 publ
32、ication. 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. A PAS is a technical specification not fulfilling the requirements for a standard
33、but made available to the public. IEC-PAS 62435 has been processed by IEC technical committee 47: Semiconductor devices. The text of this PAS is based on the following document: This PAS was approved for publication by the P-members of the committee concerned as indicated in the following document D
34、raft PAS Report on voting 47/1792/NP 47/1826/RVN Following publication of this PAS, which is a pre-standard publication, the technical committee or subcommittee concerned will transform it into an International Standard. This PAS shall remain valid for an initial maximum period of three years starti
35、ng from 2005-09. The validity may be extended for a single three-year period, following which it shall be revised to become another type of normative document or shall be withdrawn. DD IEC/PAS 62435:2005 5 INTRODUCTION This PAS applies to the long-duration storage of electronic components. Although
36、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
37、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 must be preceded by a case-by-case technical and economic feasi
38、bility 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 cov
39、ering several decades, the qualification times, and the unavailability costs, which can also be very high, the solution to be adopted to resolve obsolescence must often be rapidly implemented. This is why the solution retained in most cases consists in systematically storing components which are in
40、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, pro
41、tection, storage and test operations must 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 p
42、otential and probable degradation factors. DD IEC/PAS 62435:2005 6 ELECTRONIC COMPONENTS Long-duration storage of electronic components Guidance for implementation 1 Scope This Publicly Available Specification (PAS) is, first of all, a practical guide to methods of long-duration storage (more than f
43、ive years) which summarizes the existing practices in the industry. Unless otherwise specified, the approach, as well as the methods presented, apply to all families of electronic components, such as passive components, including quartz crystals, connectors and relays. However, components with “manu
44、facturers“ specifications showing an expiry date or specific storage conditions are excluded from this document (for example, primary cells, storage cells, etc.); encapsulated or non-encapsulated active components of a silicon Si or gallium arsenide GaAs technology; micro-electronic assemblies. 2 No
45、rmative references The following referenced documents are indispensable for the application 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 60068-2-17:1994, Basic env
46、ironmental test procedures Part 2: Tests Test Q: Sealing IEC 60068-2-20:1979, Environmental testing Part 2: Tests Test T: Soldering IEC 60410:1973, Sampling plans and procedures for inspection by attributes IEC 61340-5-1:1998, Electrostatics Part 5-1: Protection of electronic devices from electrosta
47、tic phenomena General requirements IEC 61340-5-2:1999, Electrostatics Part 5-2: Protection of electronic devices from electrostatic phenomena User guide IEC 61945, Integrated circuits Manufacturing line approval Methodology for technology and failure analysis IEC 62380: Reliability data handbook Uni
48、versal model for reliability prediction of electronics components, PCBs and equipment EN 190 000:1995, Generic specification Integrated monolithic circuits 3 Storage decision criteria Any creation of an electronic component inventory should be carried out on the one hand, after having compared with
49、the following additional solutions: modification to the printed board by adding a “backpack“ macro-component; DD IEC/PAS 62435:2005 7 development of a specific ASIC; production relaunched at a manufacturer specialized in the resumption of obsolete technological processes and components; complete revision of the board or the equipment; on the other hand, by taking into account the following aspects. 3.1 Advantages 3.1.1 Technic
