IEC 60749-21:2011

IEC 60749-21 ®
Edition 2.0 2011-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Semiconductor devices – Mechanical and climatic test methods –
Part 21: Solderability
Dispositifs à semiconducteur – Méthodes d’essai mécaniques et climatiques –
Partie 21: Brasabilité
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IEC 60749-21 ®
Edition 2.0 2011-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Semiconductor devices – Mechanical and climatic test methods –
Part 21: Solderability
Dispositifs à semiconducteur – Méthodes d’essai mécaniques et climatiques –
Partie 21: Brasabilité
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX S
ICS 31.080.01 ISBN 978-2-88912-433-6

– 2 – 60749-21  IEC:2011
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Test apparatus . 6
3.1 Solder bath. 6
3.2 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 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
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 . 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 type reflow profile . 20

Table 1 – Steam ageing conditions . 10
Table 2 – Altitude versus steam temperature . 10

60749-21  IEC:2011 – 3 –
Table 3 – Solder dip test conditions . 11
Table 4 – Maximum limits of solder bath contaminant . 13

– 4 – 60749-21  IEC:2011
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
MECHANICAL AND CLIMATIC TEST METHODS –

Part 21: Solderability
FOREWORD
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International Standard IEC 60749-21 has been prepared by IEC technical committee 47:
Semiconductor devices.
This standard cancels and replaces the first edition published in 2004 and constitutes a
technical revision. The significant change is the inclusion of Pb (lead)–free backward
compatibility.
The text of this standard is based on the following documents:
FDIS Report on voting
47/2082/FDIS 47/2089/RVD
Full information on the voting for the approval of this standard can be found in the report on
...