Experimental characterization and mechanical behavior analysis on intermetallic compounds of 96.5Sn-3.5Ag and 63Sn-37Pb solder bump with Ti-Cu-Ni UBM on copper chip

Author

Peng, Chih-Tang ; Kuo, Chia-Tai ; Chiang, Kuo-Ning ; Ku, Terry ; Chang, Kenny

Author_Institution

Dept. of Power Mech. Eng., Nat. Tsing Hua Univ., Hsinchu, Taiwan

Volume

1

fYear

2004

fDate

1-4 June 2004

Firstpage

90

Abstract

This study investigated the mechanical behavior of flip-chip lead-free solder bumps affected by solder/UBM intermetallic compound formation in the duration of isothermal aging. To attain the objective, test vehicles of Sn-Ag (lead-free) and Sn-Pb (lead-containing) solder bump systems were used to experimentally characterize and analyze their mechanical behavior. By way of metallurgical microscopy and SEM observation, the interfacial microstructure of test vehicles were measured and analyzed. In addition, a bump shear test is utilized for the strength determination of solder bumps. The results indicated that after isothermal aging treatment at 150°C for over 1000 hours, the Sn-Ag solder revealed a better maintenance of bump strength than that of Sn-Pb solder, and the Sn-Pb solder showed a higher intermetallic compounds growth rate than that of Sn-Ag solder. In terms of the solder bump volume and the UBM size effects, both the Sn-Ag and the Sn-Pb solders showed no significant effect on the intermetallic compounds growth rate.

Keywords

ageing; copper; crystal microstructure; flip-chip devices; integrated circuit packaging; lead alloys; metallurgy; nickel; scanning electron microscopy; shear strength; silver alloys; solders; tin alloys; titanium; 1000 hour; 150 degC; IMC growth rate; SEM observation; Ti-Cu-Ni-SnAg; Ti-Cu-Ni-SnPb; UBM intermetallic compound formation; UBM size effects; bump shear test; bump strength; flip-chip; interfacial microstructure; isothermal aging; lead-free solder bumps; metallurgical microscopy; shear strength; solder bump volume; Aging; Copper; Environmentally friendly manufacturing techniques; Intermetallic; Isothermal processes; Lead; Microstructure; Scanning electron microscopy; System testing; Vehicles;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic Components and Technology Conference, 2004. Proceedings. 54th

Print_ISBN

0-7803-8365-6

Type

conf

DOI

10.1109/ECTC.2004.1319320

Filename

1319320