Title :
Alternative UBM for Lead Free Solder Bumping using C4NP
Author :
Ruhmer, Klaus ; Laine, Eric ; Donnell, Kathy O. ; Kostetsky, John ; Hauck, Karin ; Manessis, Dionysios ; Ostmann, Andreas ; Toepper, Michael ; Juergensen, Nils
Author_Institution :
Waterbury Center, Waterbury
fDate :
May 29 2007-June 1 2007
Abstract :
This paper analyzes two alternative under bump metallurgy (UBM) structures: sputtered TiW/Ni and electroless Ni/immersion Au (ENIG), with and without Pd. Wafers were fabricated with these UBM structures, solder applied with C4NP, and chip level stressing performed to determine the robustness of these alternative stack-ups. Microelectronic packaging continues the migration from wire bond to flip chip first level interconnect (FLI) to meet aggressive requirements for improved electrical performance, reduced size and weight. Analysis of these structures following multiple reflows and thermal cycling is presented.
Keywords :
chip scale packaging; flip-chip devices; integrated circuit interconnections; nickel alloys; solders; titanium alloys; tungsten alloys; wafer level packaging; C4NP technology; TiW-Ni; alternative under bump metallurgy structure; chip level stressing; controlled collapse chip connection new process; electrical performance; electroless Ni-immersion Au UBM structure; flip chip first level interconnect; lead free solder bumping; microelectronic packaging; palladium; sputtered TiW-Ni UBM structure; thermal cycling; wafers fabrication; wire bond; Environmentally friendly manufacturing techniques; Flip chip; Gold; Lead; Microelectronics; Packaging; Performance analysis; Robustness; Wafer bonding; Wire;
Conference_Titel :
Electronic Components and Technology Conference, 2007. ECTC '07. Proceedings. 57th
Conference_Location :
Reno, NV
Print_ISBN :
1-4244-0985-3
Electronic_ISBN :
0569-5503
DOI :
10.1109/ECTC.2007.373770
