Title :
Development of fluxes for selected Sn-Cu based lead-free solders
Author :
Yang, Min ; Liu, Xiuzhong ; Wang, Chunqing ; Zou, Zengda ; Jiang, Dalei
Author_Institution :
Sch. of Mater. Sci. & Eng., Shandong Univ., Jinan, China
fDate :
30 Aug.-2 Sept. 2005
Abstract :
Fluxes which are suitable for Sn-0.8Cu and Sn-0.8Cu-3Bi lead-free solder have been investigated in this paper. Fluxes were evaluated in spread test by measuring the spread areas of solders on copper substrate. The effect of flux on the intermetallic compounds (IMCs) at the interface between solder and copper substrate was studied through analyzing the morphology of IMCs of interface by electron probe microanalysis (EPMA). Results show that both NST flux (flux consists of natural rosin and SnCl2) and SAT flux (by adding SnCl2 into stearic acid ) can greatly improve the wetting ability of Sn-Cu based lead-free solder on copper substrate. SnCl2 in flux influences the morphology and thickness of IMCs at the interface of solder/Cu joint. The concentration of SnCl2 contained in fluxes also affects the spread areas of solder on copper plate.
Keywords :
copper alloys; electron probe analysis; materials testing; solders; surface morphology; tin alloys; NST flux; SAT flux; SnCl2; SnCuBi; electron probe microanalysis; interface morphology; intermetallic compounds; lead-free solders; spread test; wetting ability; Area measurement; Conducting materials; Copper; Electronics packaging; Environmentally friendly manufacturing techniques; Lead; Materials science and technology; Morphology; Testing; Tin;
Conference_Titel :
Electronic Packaging Technology, 2005 6th International Conference on
Print_ISBN :
0-7803-9449-6
DOI :
10.1109/ICEPT.2005.1564733
