1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationSemiconductor devices Mechanical and climatic test methodsPart 21: SolderabilityBS EN 60749-21:2011National forewordThis British Standard is the UK implementation of EN 60749-21:
2、2011. It isidentical to IEC 60749-21:2011. It supersedes BS EN 60749-21:2005 which iswithdrawn.The UK participation in its preparation was entrusted to Technical CommitteeEPL/47, Semiconductors.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publ
3、ication does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application. BSI 2011ISBN 978 0 580 69115 7ICS 31.080.01Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the a
4、uthority of the StandardsPolicy and Strategy Committee on 31 August 2011.Amendments issued since publicationAmd. No. Date Text affectedBRITISH STANDARDBS EN 60749-21:2011EUROPEAN STANDARD EN 60749-21 NORME EUROPENNE EUROPISCHE NORM August 2011 CENELEC European Committee for Electrotechnical Standard
5、ization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Management Centre: Avenue Marnix 17, B - 1000 Brussels 2011 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60749-21:2011 E I
6、CS 31.080.01 Supersedes EN 60749-21:2005English version Semiconductor devices - Mechanical and climatic test methods - Part 21: Solderability (IEC 60749-21:2011) Dispositifs semiconducteur - Mthodes dessai mcaniques et climatiques - Partie 21: Brasabilit (CEI 60749-21:2011) Halbleiterbauelemente - M
7、echanische und klimatische Prfverfahren - Teil 21: Ltbarkeit (IEC 60749-21:2011) This European Standard was approved by CENELEC on 2011-05-12. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of
8、a national 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 ver
9、sion in any 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, Bulgaria, Croatia,
10、 Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. BS EN 60749-21:2011EN 60
11、749-21:2011 - 2 - Foreword The text of document 47/2082/FDIS, future edition 2 of IEC 60749-21, prepared by IEC TC 47, Semiconductor devices, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60749-21 on 2011-05-12. This European Standard supersedes EN 60749-21:2005. E
12、N 60749-21:2011 cancels and replaces EN 60749-21:2005 and constitutes a technical revision. The significant change is the inclusion of Pb (lead)free backward compatibility. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and C
13、ENELEC shall not be held responsible for identifying any or all such patent rights. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2012-02-12 latest date by which the nationa
14、l standards conflicting with the EN have to be withdrawn (dow) 2014-05-12 Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 60749-21:2011 was approved by CENELEC as a European Standard without any modification. In the official version, for Bibliograp
15、hy, the following notes have to be added for the standards indicated: IEC 60068 series NOTE Harmonized in EN 60068 series. IEC 60068-2-69:2007 NOTE Harmonized as EN 60068-2-69:2007 (not modified). IEC 60749 series NOTE Harmonized in EN 60749 series. IEC 60749-15:2003 NOTE Harmonized as EN 60749-15:2
16、003 (not modified). IEC 60749-20:2008 NOTE Harmonized as EN 60749-20:2009 (not modified). _ BS EN 60749-21:2011- 3 - EN 60749-21:2011 Annex ZA (normative) Normative references to international publications with their corresponding European publications The following referenced documents are indispen
17、sable 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. NOTE When an international publication has been modified by common modifications, indicated by (
18、mod), the relevant EN/HD applies. Publication Year Title EN/HD Year IEC 61190-1-2 2007 Attachment materials for electronic assembly - Part 1-2: Requirements for soldering pastes for high-quality interconnects in electronics assembly EN 61190-1-2 2007 IEC 61190-1-3 2007 Attachment materials for elect
19、ronic assembly - Part 1-3: Requirements for electronic grade solder alloys and fluxed and non-fluxed solid solders for electronic soldering applications EN 61190-1-3 2007 BS EN 60749-21:2011 2 60749-21 IEC:2011 CONTENTS 1 Scope . 6 2 Normative references . 6 3 Test apparatus . 6 3.1 Solder bath 6 3.
20、2 Dipping device. 6 3.3 Optical equipment . 7 3.4 Steam ageing equipment . 7 3.5 Lighting equipment 7 3.6 Materials . 7 3.6.1 Flux . 7 3.6.2 Solder . 7 3.7 SMD reflow equipment 8 3.7.1 Stencil or screen . 8 3.7.2 Rubber squeegee or metal spatula 8 3.7.3 Test substrate . 8 3.7.4 Solder paste 9 3.7.5
21、Reflow equipment 9 3.7.6 Flux removal solvent 9 4 Procedure 9 4.1 Lead-free backward compatibility 9 4.2 Preconditioning . 10 4.2.1 General . 10 4.2.2 Preconditioning by steam ageing . 10 4.2.3 Preconditioning by high temperature storage . 11 4.3 Procedure for dip and look solderability testing . 11
22、 4.3.1 General . 11 4.3.2 Solder dip conditions . 11 4.3.3 Procedure 11 4.4 Procedure for simulated board mounting reflow solderability testing of SMDs 19 4.4.1 General . 19 4.4.2 Test equipment set-up . 19 4.4.3 Specimen preparation and surface condition . 20 4.4.4 Visual inspection . 21 5 Summary
23、21 Bibliography 22 Figure 1 Areas to be inspected for gullwing packages 15 Figure 2 Areas to be inspected for J-lead packages . 16 Figure 3 Areas to be inspected in rectangular components (SMD method) 17 Figure 4 Areas to be inspected in SOIC and QFP packages (SMD method) . 18 Figure 5 Flat peak typ
24、e reflow profile . 20 Table 1 Steam ageing conditions . 10 Table 2 Altitude versus steam temperature 10 BS EN 60749-21:201160749-21 IEC:2011 3 Table 3 Solder dip test conditions 11 Table 4 Maximum limits of solder bath contaminant . 13 BS EN 60749-21:2011 6 60749-21 IEC:2011 SEMICONDUCTOR DEVICES ME
25、CHANICAL AND CLIMATIC TEST METHODS Part 21: Solderability 1 Scope This part of IEC 60749 establishes a standard procedure for determining the solderability of device package terminations that are intended to be joined to another surface using tin-lead (SnPb) or lead-free (Pb-free) solder for the att
26、achment. This test method provides a procedure for dip and look solderability testing of through hole, axial and surface mount devices (SMDs) as well as an optional procedure for a board mounting solderability test for SMDs for the purpose of allowing simulation of the soldering process to be used i
27、n the device application. The test method also provides optional conditions for ageing. This test is considered destructive unless otherwise detailed in the relevant specification. NOTE 1 This test method is in general accord with IEC 60068, but due to specific requirements of semiconductors, the fo
28、llowing text is applied. NOTE 2 This test method does not assess the effect of thermal stresses which may occur during the soldering process. Reference should be made IEC 60749-15 or IEC 60749-20. 2 Normative references The following referenced documents are indispensable for the application of this
29、 document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 61190-1-2:2007, Attachment materials for electronic assembly Part 1-2: Requirements for soldering pastes for high-quality int
30、erconnects in electronics assembly IEC 61190-1-3:2007, Attachment materials for electronic assembly Part 1-3: Requirements for electronic grade solder alloys and fluxed and non-fluxed solid solders for electronic soldering applications 3 Test apparatus This test method requires the following equipme
31、nt. 3.1 Solder bath The solder bath shall be not less than 40 mm in depth and not less than 300 ml in volume such that it can contain at least 1 kg of solder. The apparatus shall be capable of maintaining the solder at the specified temperature within 5 C. 3.2 Dipping device A mechanical dipping dev
32、ice capable of controlling the rates of immersion and emersion of the terminations and providing a dwell time (time of total immersion to the required depth) in the solder bath as specified shall be used. BS EN 60749-21:201160749-21 IEC:2011 7 3.3 Optical equipment An optical microscope capable of p
33、roviding magnification inspection from 10 to 20 shall be used. 3.4 Steam ageing equipment A non-corrodible container and cover of sufficient size to allow the placement of specimens inside the vessel shall be used. The specimens shall be placed such that the lowest portion of the specimen is a minim
34、um of 40 mm above the surface of the water. A suitable method of supporting the specimens shall be improvised using non-contaminating material. NOTE During steam ageing, the test devices should be located in a manner so as to prevent water (steam condensate) from dripping on them. 3.5 Lighting equip
35、ment A lighting system shall be used that will provide a uniform, non-glare, non-directional illumination of the specimen. 3.6 Materials 3.6.1 Flux Unless otherwise detailed in the relevant specification, the flux shall be a standard activated rosin flux (type ROL1 in accordance with IEC 61190-1-3 (
36、2007), Table 2, Flux type and designating symbols) having a composition of 25 % 0,5 % by weight of colophony and 0,15 % 0,01 % by weight diethylammonium hydrochloride, in 74,85 % 0,5 % by weight of in 2-propanol (isopropanol). The specific gravity of the standard activated rosin flux shall be 0,843
37、0,005 at 25 C 2 C. The specification shall be as follows: Colophony Colour To WW colour specification or paler Acid value (mg KOH/g colophony) 155 (minimum) Softening point (ball and ring) 70 C (minimum) Flow point (Ubbelohde) 76 C (minimum) Ash 0,05 % (maximum) Solubility A solution of the colophon
38、y in an equal part by weight of 2-propanol (isopropanol) shall be clear, and after a week at room temperature there shall be no sign of a deposit. 2-propanol (isopropanol) Purity Minimum 99,5 % 2-propanol (isopropanol) by weight Acidity as acetic acid Maximum 0,002 % weight (other than carbon dioxid
39、e) Non-volatile matter Maximum 2 mg per 100 ml. 3.6.2 Solder 3.6.2.1 Tin-lead Unless otherwise detailed in the relevant specification, the solder specification for SnPb shall be as follows: Chemical composition BS EN 60749-21:2011 8 60749-21 IEC:2011 The composition in percentage by weight shall be
40、as follows: Tin 59 % to 61 % Antimony 0,5 % maximum Copper 0,1 % maximum Arsenic 0,05 % maximum Iron 0,02 % maximum Lead the remainder. The solder shall not contain such impurities as aluminium, zinc or cadmium in amounts which will adversely affect the properties of the solder. Melting temperature
41、range The melting temperature range of the 60 % solder is as follows: Completely solid 183 C Completely liquid 188 C. 3.6.2.2 Lead-free Unless otherwise detailed in the relevant specification, the solder specification for Pb-free shall be as follows: The composition in percentage by weight shall be
42、as follows: Tin 95 % to 96,5 % Silver 3 % to 4 % Copper 0,5 % to 1 %. 3.7 SMD reflow equipment 3.7.1 Stencil or screen A stencil or screen with pad geometry opening that is appropriate for the terminals being tested. Unless otherwise agreed upon between vendor and user, nominal stencil thickness sho
43、uld be 0,1 mm for terminals with less than 0,5 mm component lead pitch, 0,15 mm for a component with lead pitch of 0,5 mm to 0,65 mm and 0,2 mm for a component with lead pitch greater than 0,65 mm. 3.7.2 Rubber squeegee or metal spatula Solder paste shall be applied on to the stencil or screen using
44、 a spatula for fine pitch or a squeegee for standard pitch. 3.7.3 Test substrate SMD specimens for simulated board mounting reflow solderability testing shall be evaluated using a substrate. NOTE 1 A ceramic (alumina 90 % - 98 %) may be used for all reflow requirements. NOTE 2 A glass epoxy substrat
45、e may be used for all reflow requirements. The glass epoxy substrate should be capable of withstanding the soldering temperature (e.g. it is not suitable for hot plate soldering). NOTE 3 For visual inspection of the tested device terminations, the test substrate should be unmetallized (no lands). BS
46、 EN 60749-21:201160749-21 IEC:2011 9 3.7.4 Solder paste Unless otherwise specified, the composition of the solder paste shall be as follows. 3.7.4.1 Pb-containing paste The solder composition shall be as specified in 3.6.2. Unless otherwise specified in the relevant specification, the particle size
47、of the solder powder shall be 20 m to 45 m. The composition of the flux shall be as specified in 3.6.1. The viscosity range of the solder paste and method of measurement shall be detailed in the relevant specification. 3.7.4.2 Pb-free paste The solder composition shall be as specified in 3.6.2. The
48、solder powder size shall be 4 as defined in Table 2 of IEC 61190-1-2:2007, viz: no particle larger than 40m ; less than 1 %, larger than 38 m; at least 90 %, between 38 m and 20 m; less than 10 %, smaller than 22 m. The shape of solder powder shall be spherical. The flux to be used shall consist of
49、30 wt % of polymerization rosin (softening point, approximately 95 C), 30 wt % of dibasic acid degeneration rosin (softening point, approximately 140 C), 34,7 wt % of diethylene glycol monobutyl ether, 0,9 wt % of 1,3-diphenylguanidine-HBr, 0,5 wt % of adipic acid (chlorine content less than 0,1 wt %) and 4 wt % of stiffening castor oil. The solder paste to be used shall consist of 88 wt % of solder powder and 12 wt % of flux. The v
