Electromigration in flip chip solder bump of 97Pb-3Sn/37Pb-63Sn combination structure

被引:51
作者
Nah, JW [1 ]
Kim, JH [1 ]
Lee, HM [1 ]
Paik, KW [1 ]
机构
[1] Korea Adv Inst Sci & Technol, Dept Mat Sci & Engn, Taejon 305701, South Korea
关键词
electromigration; phase transformation; intermetallic compounds; diffusion; soldering;
D O I
10.1016/j.actamat.2003.08.035
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Electromigration damage in the flip chip solder bump of 97Pb-3Sn/37Pb-63Sn (numbers are all in wt% unless specified otherwise) combination structure was studied after current stressing at 140 degreesC with a density of 2.55 x 10(4) A/cm(2) for up to 20 h. The under bump metallurgy for the 97Pb-3Sn solder on the chip side was TiW/Cu/electroplated Cu while the bond-pad for the 37Pb-63Sn solder on the printed circuit board (PCB) side was electroless Ni/Au. We observed in the thermo-electromigration test that failure occurred at the top of the bump with a downward electrical current flow while there was no failure in the opposite current polarity. The Pb atoms were found to move in the same direction as with the electron current flow. Therefore, in the case of the downward electron flow, the composition of the upper solder bump changed from 97Pb-3Sn to 83Pb-17Sn and it enabled the Cu6Sn5 phase to precipitate onto the chip side. Due to the precipitation and growth of the Cu6Sn5 intermetallic compound, the Cu under bump metallurgy was quickly consumed and the subsequent void formation induced failure. (C) 2003 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
引用
收藏
页码:129 / 136
页数:8
相关论文
共 27 条
[1]   Electromigration of flip chip solder bump on Cu/Ni(V)/Al thin film under bump metallizaton [J].
Choi, WJ ;
Yeh, ECC ;
Tu, KN .
52ND ELECTRONIC COMPONENTS & TECHNOLOGY CONFERENCE, 2002 PROCEEDINGS, 2002, :1201-1205
[2]   Thermodynamic modeling of the nickel-lead-tin system [J].
Ghosh, G .
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE, 1999, 30 (06) :1481-1494
[3]   THE FORMATION OF CU3SN INTERMETALLIC ON THE REACTION OF CU WITH 95PB-5SN SOLDER [J].
GRIVAS, D ;
FREAR, D ;
QUAN, L ;
MORRIS, JW .
JOURNAL OF ELECTRONIC MATERIALS, 1986, 15 (06) :355-359
[4]   Interface diffusion in eutectic Pb-Sn solder [J].
Gupta, D ;
Vieregge, K ;
Gust, W .
ACTA MATERIALIA, 1998, 47 (01) :5-12
[5]  
HAYES FH, 1986, Z METALLKD, V77, P749
[6]  
Huntington H., 1975, DIFFUSION SOLIDS REC, P303
[7]  
JANG SY, 2002, THESIS KAIST TAEJON
[8]  
Karakaya I., 1988, B ALLOY PHASE DIAGRA, V9, P144, DOI [10.1007/BF02890552, DOI 10.1007/BF02890552]
[9]  
Kirkaldy J.S., 1987, DIFFUSION CONDENSED
[10]  
Lau J. H., 1996, FLIP CHIP TECHNOLOGI, P123