1、BRITISH STANDARD BS EN 61751:1998 IEC 61751:1998 Laser modules used for telecommunication Reliability assessment The European Standard EN 61751:1998 has the status of a British Standard ICS 31.260BSEN61751:1998 This British Standard, having been prepared under the direction of the Electrotechnical S
2、ector Board, was published under the authority of the Standards Board and comes into effect on 15 September 1998 BSI 05-1999 ISBN 0 580 30143 5 National foreword This British Standard is the English language version of EN 61751:1998. It is identical with IEC 61751:1998. The UK participation in its p
3、reparation was entrusted to Technical Committee EPL/86, Fibre optics, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; m
4、onitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. From 1 January 1997, all IEC publications have the number 60000 added to the old number. For instance, IEC 27-1 has
5、 been renumbered as IEC 60027-1. For a period of time during the change over from one numbering system to the other, publications may contain identifiers from both systems. Cross-references Attention is drawn to the fact that CEN and CENELEC standards normally include an annex which lists normative
6、references to international publications with their corresponding European publications. The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspon
7、dence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of
8、 itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN title page, pages 2 to 30, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incor
9、porated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsBSEN61751:1998 BSI 05-1999 i Contents Page National foreword Inside front cover Foreword 2 Text of EN 61751 5ii blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCH
10、E NORM EN 61751 April 1998 ICS 31.260 Descriptors: Laser modules, telecommunication, reliability English version Laser modules used for telecommunication Reliability assessment (IEC 61751:1998) Modules laser utiliss pour les tlcommunications Evaluation de la fiabilit (CEI 61751:1998) Lasermodule fr
11、Telekommunikationsanwendungen Zuverlsigkeitsbewertung (IEC 61751:1998) This European Standard was approved by CENELEC on 1998-04-01. 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
12、 standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in an
13、y other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic, Denmark, Fin
14、land, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische N
15、ormung Central Secretariat: rue de Stassart 35, B-1050 Brussels 1998 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 61751:1998 EEN61751:1998 BSI 05-1999 2 Foreword The text of document 86/115/FDIS, future edition 1 of IEC 61751, pr
16、epared by SC 47C, Optoelectronic, display and imaging devices, of IEC TC 47, Semiconductor devices, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61751 on 1998-04-01. The following dates were fixed: Annexes designated “normative” are part of the body of the standar
17、d. Annexes designated “informative” are given for information only. In this standard, Annex A and Annex ZA are normative and Annex B is informative. Annex ZA has been added by CENELEC. Endorsement notice The text of the International Standard IEC 61751:1998 was approved by CENELEC as a European Stan
18、dard without any modification. Contents Page Foreword 2 Introduction 5 1 Scope 5 2 Normative references 5 3 Terms and definitions 5 4 Laser reliability and quality assurance procedure 6 4.1 Demonstration of product quality 6 4.2 Testing responsibilities 6 4.3 Quality Improvement Programmes (QIPs) 6
19、5 Tests 6 5.1 Structural similarity 7 5.2 Burn-in and screening (when applicable in the DS) 7 6 Activities 10 6.1 Analysis of reliability results 10 6.2 Technical visits to LMMs 11 6.3 Design/process changes 11 6.4 Deliveries 11 6.5 Supplier documentation 11 Annex A (normative) Laser diode and laser
20、 module failure mechanisms 12 Annex B (informative) Guide 18 Annex ZA (normative) Normative referencestointernational publicationswiththeir correspondingEuropean publications Inside back cover Figure A.1 Non-linearities in laser-current characteristics 14 Figure A.2 “Bathtub” failure rate curve 15 F
21、igure A.3 Example of cumulative failure plot showing log-normal distribution of laser failure rate 15 Figure A.4 Calculated failure rates for components having a log-normal lifetime distribution, with a median life of 10 6h and dispersion in the range 0,5 to 2,0 16 Figure A.5 Cross-section through a
22、 typical laser module showing key components 16 Figure A.6 Cross-section through a typical buried heterostructure laser (bonded junction side up) 17 Table 1 Qualification testing 8 Table 1a Initial qualifications (see notes for symbols) 8 latest date by which the EN has to be implemented at national
23、 level by publication of an identical national standard or by endorsement (dop) 1999-01-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2001-01-01EN61751:1998 BSI 05-1999 3 Page Table 1b Maintenance of qualification 10 Table 2 Proforma for laser modu
24、le reliability parameters 11 Table B.1 Recommended life test conditions for laser modules containing Peltier coolers 18 Table B.2 Recommended life test conditions for uncooled laser modules 19 Table B.3 Recommended laser diode life test conditions 19 Table B.4 Recommended photodiode life test condit
25、ions 20 Table B.5 Recommended laser diode screening and burn-in conditions 21 Table B.6 Recommended monitor photodiode screening conditions 22 Table B.7 Recommended life test failure criteria 23 Table B.8 Recommended (optional) additional failure criteria for laser module service life tests 24 Table
26、 B.9 Recommended failure criteria for laser modules after temperature cycling testing and high-temperature storage testing 24 Table B.10 Recommended values of activation energy for lifetime predictions (when an experimentally determined value is not available, i.e. default values) 26 Table B.11 Coef
27、ficient for upper and lower level of median life in log-normal distribution, (t mp /t mh )1/B 28 Table B.12 Multiplying coefficient for upper and lower level of dispersion 29 Table B.13 Failure rate for an exponential lifetime distribution 304 blankEN61751:1998 BSI 05-1999 5 Introduction The laser m
28、odules covered by this International Standard are purchased by a system supplier (SS) to be inserted in equipments which in turn are supplied/sold to a system operator (SO), for example a national PTT or a network operator (see definitions in clause 3). For the system operator to act as an informed
29、buyer, a knowledge of the potential risks posed by the use of critical components is required. Optoelectronic component technology is continuing to develop. Consequently, during product development phases, many failure mechanisms in laser modules have been identified. These failure mechanisms, if un
30、detected, could result in very short laser lifetime in system use. 1 Scope This International Standard deals with reliability assessment of laser modules used for telecommunication. The aim of this standard is: to establish a standard method of assessing the reliability of laser modules in order to
31、minimize risks and to promote product development and reliability; to establish means by which the distribution of failures with time can be determined. This should enable the determination of equipment failure rates for specified end of life criteria. In addition, guidance is given on: the testing
32、that a system supplier should ensure is in a place prior to procurement of a laser module from a laser module manufacturer; a range of activities expected of a system supplier to verify a laser module manufacturers reliability claims. Further details concerning the rationale are given in Annex A and
33、 Annex B. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All normative documents are subject to revision, and parti
34、es to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. IEC 60068-2-1:1990, Environmental
35、 testing Part 2: Tests. Tests A: Cold. IEC 60068-2-14:1984, Environmental testing Part 2: Tests. Test N: Change of temperature. IEC 60747-1:1996, Semiconductor devices Discrete devices and integrated circuits Part 1: General Amendment 3 (1996). IEC 60747-12-2:1995, Semiconductor devices Part 12: Opt
36、oelectronic devices Section 2: Blank detail specification for laser diode modules with pigtail for fibre optic systems and sub-systems. IEC 60749:1996, Semiconductor devices Mechanical and climatic test methods. ISO 9000, Quality management and quality assurance standards. MIL-STD-883:1985, Test met
37、hods and Procedures for Microelectronics. 3 Terms and definitions For the purpose of this International Standard the following definitions apply: laser module a packaged assembly containing a laser diode and photodiode NOTEThe module may also include a cooler and temperature sensor to enable laser t
38、emperature to be controlled and monitored. The optical output is normally via an optical fibre pigtail. submount a substrate upon which a laser diode or photodiode may be mounted for assembly into the laser module NOTEComponents on submounts are also subject to qualification testing. laser module ma
39、nufacturer (LMM) a manufacturer of laser modules who provides devices meeting the requirements of the relevant detail specification (DS) and the customers reliability requirements system supplier (SS) a manufacturer of telecommunications/data transmission equipment containing optoelectronic semicond
40、uctor lasers, i.e. laser module customer system operator (SO) a network operator of telecommunications/data transmission equipment containing optoelectronic semiconductor lasers in the transmission path NOTEThe system may also be part of other more extensive systems, for example telecommunications,
41、rail, road vehicles, aerospace or weapons.EN61751:1998 6 BSI 05-1999 capability qualifying components (CQC) components selected to represent critical stages of the process and limiting or boundary characteristics of mechanical and electro-optic design such components should aid the identification of
42、 end product failure mechanisms to enable the determination of activation energies 4 Laser reliability and quality assurance procedure 4.1 Demonstration of product quality This standard where required by the detail specification (DS) gives the minimum mandatory requirements and is part of a total la
43、ser reliability and quality assurance procedure adopted by the laser module manufacture. It gives guidance on the activities of the system supplier, and the system operator as well as feedback of field performance, the laser module manufacturer and the system supplier. The laser module manufacturer
44、shall be able to demonstrate, by means of qualification approval of devices, technology approval or capability approval of the manufacturing process: a) a documented and audited manufacturing process including the qualification of purchased components in accordance with ISO 9000; b) a performance qu
45、alification programme, including for example, accelerated life testing, burn-in and screening of components and modules; c) a qualification maintenance programme to ensure continuity of reliability performance; d) a procedure to feedback reliability issues to development and production. In addition,
46、 there are many elements which make up a comprehensive reliability assurance programme (seeAnnex B). 4.2 Testing responsibilities The testing detailed in Table 1a and Table 1b is to be performed by the laser module manufacturer and component suppliers (where applicable). Additional testing may be sp
47、ecified in the DS. 4.2.1 Recommendation (applicable to laser customer/system supplier) The system supplier is recommended to have a programme to analyse and verify the results including failure analysis. This programme includes an independent life test of fully packaged laser modules, see Table 1b t
48、est 2 and/or test 3 and/or test 5 (sample size 10 per test). 4.2.2 Recommendation applicable to system operator The system operator is recommended to have a programme to monitor and report field failure rates in sufficient detail to enable system supplier and laser module manufacturer to initiate an
49、y necessary corrective actions at an early stage in the lifetime of a product. Suppliers may have different approaches (i.e. to reliability concepts) during the development of product maturity and resource limitations may dictate testing strategies. Alternative tests and activities to those specified are permitted provided the LMM/SS/SO can show intent to remove end-product failures and the associated failure mechanisms. However, this will require significant data to substantiate com
