Pb-free plating: a process and solder joint reliability study

Author

Ong, Ming Sing ; Lau, Yi Ming ; Tan, Ah Chin

Author_Institution

Micron Semicond. Asia Pte. Ltd.

fYear

2004

fDate

8-10 Dec. 2004

Firstpage

162

Lastpage

168

Abstract

The lead-free (Pb-free/100% tin) lead finish quality from two plating suppliers was compared to that of standard 90wt%Sn-1 0wt%Pb plating. A characterization study of the properties of the electroplated tin (Sn) showed that the finish exhibited large stable grains, high purity, comparable ionic contamination levels, and solderability. The assembled modules that employed Pb-free paste for the Sn finish showed better temperature cycling (T/C) performance, as those with Sn-Pb paste showed distinguished crack propagation. Sn whisker observation and characterization were performed on the components at time-zero, after module reflow and with the progression of T/C. The Sn whisker growth rates are explained in relation to tensile and compressive stresses on the plated layer

Keywords

assembling; compressive strength; cracks; electroplating; lead; reflow soldering; surface treatment; tensile strength; tin; whiskers (crystal); Pb; Pb free plating; Pb-free paste; Sn; Sn whiskers; compressive stresses; crack propagation; cycling performance; electroplated tin; finish temperature; grains stability; ionic contamination levels; module reflow; plating suppliers; solder joint reliability; solder paste; solderability; tensile stresses; time-zero; Contamination; Environmentally friendly manufacturing techniques; Lead; Packaging; Scanning electron microscopy; Soldering; Strips; Temperature; Testing; Tin;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronics Packaging Technology Conference, 2004. EPTC 2004. Proceedings of 6th

Conference_Location

Singapore

Print_ISBN

0-7803-8821-6

Type

conf

DOI

10.1109/EPTC.2004.1396596

Filename

1396596