Results of comparative reliability tests on lead-free solder alloys

Author

Grossmann, Günter ; Nicoletti, Giovanni ; Solèr, Ursin

Author_Institution

Res. EMPA, Swiss Fed. Inst. for Mater. Testing, Dubendorf, Switzerland

fYear

2002

fDate

6/24/1905 12:00:00 AM

Firstpage

1232

Lastpage

1237

Abstract

The use of lead-free solder brings up concerns regarding the reliability of the new alloys to be used. In a European project (LEADFREE) SnAg, SnAgCu, SnAgCuSb, SnZn and SnPbAg have been tested in order to evaluate comparative data of the growth of cracks in solder joints. Reliability tests performed in other projects use accelerated tests proposed for tin-lead solders and showed a superior reliability of lead free solder over tin-lead alloys. The validity of these tests has to be questioned since they do not allow full relaxation of the stresses in solder joints. Thus each alloy is subject to another amount of strain. LEADFREE tests are run with slow temperature ramps and long dwell times to account for this fact. As a result a faster growth of cracks has been observed in lead free solder joints compared to Sn62Pb36Ag2.

Keywords

copper alloys; cracks; deformation; life testing; packaging; relaxation; reliability; silver alloys; soldering; tin alloys; zinc alloys; LEADFREE European project; Pb-free solder alloys; SnAg; SnAgCu; SnAgCuSb; SnPbAg; SnZn; accelerated tests; comparative reliability tests; crack growth; lead-free solder; long dwell times; slow temperature ramps; solder joints; stress relaxation; Capacitive sensors; Creep; Deformable models; Environmentally friendly manufacturing techniques; Lead; Soldering; Temperature; Testing; Thermal degradation; Thermal stresses;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic Components and Technology Conference, 2002. Proceedings. 52nd

ISSN

0569-5503

Print_ISBN

0-7803-7430-4

Type

conf

DOI

10.1109/ECTC.2002.1008264

Filename

1008264