Effect of Composition and Cooling Rate on the Microstructure of SnAgCu-Solder Joints

Research output: Contribution to book/Conference proceedings/Anthology/ReportConference contributionContributed

Contributors

Abstract

In this study the solder alloys SnAg3.5, SnAg3.0Cu0.5, SnAg3.8Cu0.7 and SnAg2.7Cu0.4Ni0.05 have been analysed in order to determine variations in microstructure caused by cooling rate, solder composition and ball diameter. Solder spheres with a diameter of approx. Ø 1100 μm, Ø 590 μm, Ø 270 μm and Ø 130 μm were solidified with cooling rates of 0.14K/s, 1.1K/s and 10.9K/s. Cross sections of these specimens were analysed by optical light microscopy. Interpretations of the analysed microstructure allow a description of the solidification process, which takes place in a solder ball. It could be concluded that this process is divided in three stages: the formation of primary intermetallics, the formation of fine structured regions and the formation of coarse dendritic areas.

Details

Original languageGerman
Title of host publication2007 Proceedings 57th Electronic Components and Technology Conference
PublisherIEEE
Pages1579-1588
Number of pages10
ISBN (print)1-4244-0985-3
Publication statusPublished - 1 Jun 2007
Peer-reviewedNo

Conference

Title2007 57th Electronic Components and Technology Conference
Conference number57
Duration29 May - 1 June 2007
CitySparks
CountryUnited States of America

External IDs

Scopus 35348925915

Keywords

Keywords

  • Microstructure, Flip chip, Electronics cooling, Optical microscopy, Environmentally friendly manufacturing techniques, Lead, Cause effect analysis, Intermetallic, Metallization, Thermomechanical processes