Flip chip reliability: comparative characterization of lead free (Sn/Ag/Cu) and 63Sn/Pb eutectic solder

Author

Balkan, Haluk ; Patterson, Deborah ; Burgess, Guy ; Carlson, Craig ; Elenius, Peter ; Johnson, Michael ; Rooney, Brian ; Sanchez, Joseph ; Stepniak, David ; Wood, Jim

Author_Institution

Flip Chip Div., Kulicke & Soffa, Phoenix, AZ, USA

fYear

2002

fDate

6/24/1905 12:00:00 AM

Firstpage

1263

Lastpage

1269

Abstract

The reliability of a ternary Sn/Ag/Cu alloy for flip chip solder joints will be reported in this paper. Dominant failure mechanisms for given thermal stress regimes are well defined for 63Sn/Pb eutectic solder. Characterizing Sn/Ag/Cu solder reliability in comparison to 63Sn/Pb solder provides a true baseline for these thermal stress regimes and still allows for a broad search of mechanisms due to the change in alloy properties inherent in this new metallurgic system. Reliability characterization must examine both solder bump and under bump metallization (UBM) robustness, because the interaction between the two contributes to the overall efficacy of the structure. Reported in this work are thermal cycle, high temperature storage, and die shear test results demonstrating the solder bump reliability. Electromigration, multiple reflow, and bare die high temperature test results verifying the UBM robustness are also presented. In addition, the assembly-related details are reported in an effort to provide a foundation for improved yield.

Keywords

chip scale packaging; copper alloys; electromigration; environmental degradation; eutectic alloys; failure analysis; flip-chip devices; integrated circuit bonding; integrated circuit interconnections; integrated circuit metallisation; integrated circuit reliability; integrated circuit testing; lead alloys; reflow soldering; silver alloys; tin alloys; SnPb eutectic solder; UBM robustness; bare die high temperature tests; device yield improvement; die shear tests; electromigration; flip chip solder joint reliability; high temperature storage; lead-free alloy properties; multiple reflow tests; solder bump metallization; ternary Pb-free SnAgCu alloys; thermal cycle tests; thermal stress failure mechanisms; thermal stress regimes; under bump metallization; Copper alloys; Environmentally friendly manufacturing techniques; Flip chip; Flip chip solder joints; Lead; Robustness; Temperature; Testing; Thermal stresses; Tin;

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.2002.1008268

Filename

1008268