Advanced Search  
JWJ > Volume 23(3); 2005 > Article
Journal of KWJS 2005 June;23(3) :61-67.
Published online July 15, 2005.
Lower Temperature Soldering of Capacitor Using Sn-Bi Coated Sn-3.5%Ag Solder
Mi-Jin Kim, Sun-Yun Cho, Sook-Hwan Kim, Jae-Pil Jung



Correspondence:   Published online July 15, 2005
ABSTRACT
Since lead (Pb)-free solders for electronics have higher melting points than that of eutectic Sn-Pb solder, they need higher soldering temperatures. In order to decrease the soldering temperature we tried to coat Sn-Bi layer on Sn-3.5%Ag solder by electroplating, with applies the mechanism of transient liquid phase bonding to soldering. During heating Bi will diffuse into the Sn-3.5Ag solder and this results in decreasing soldering temperature. As bonding samples, the 1608 capacitor electroplated with Sn, and PCB, its surface was finished with electroless-plated Ni/Au, were selected. The Sn-95.7%Bi coated Sn-3.5Ag was supplied as a solder between the capacitor and PCB land. The samples were reflowed at 220℃, which was lower than that of normal reflow temperature, 240~250℃, for the Pb-free. As experimental result, the joint of Sn-95.7%Bi coated Sn-3.5Ag showed high shear strength. In the as-reflowed state, the shear strength of the coated solder showed 58.8N, whereas those of commercial ones were 37.2N (Sn-37Pb), 31.4N (Sn-3Ag-0.5Cu), and 40.2N (Sn-8Zn-3Bi). After thermal shock of 1000 cycles between -40℃ and +125℃N and 45.1N. As the microstructures, in the solder Ag₃Sn intermetallic compound (IMC), and along the bonded interface Ni₃Sn₄ IMC were observed.
TOOLS
PDF Links  PDF Links
Full text via DOI  Full text via DOI
Download Citation  Download Citation
CrossRef TDM  CrossRef TDM
  E-Mail
Share:      
METRICS
3,004
View
0
Download
Related articles
Low Temperature Bonding Process of Silicon and Glass using Spin-on Glass  2005 December;23(6)
Thermal Fatigue Life Prediction of μBGA Solder Joint Using Sn-37mass%Pb Solder and Sn-3.5mass%Ag Lead-free Solder   2001 August;19(4)
Low Temperature Bonding Process of Silicon and Glass using Spin-on Glass  2005 December;23(6)
Thermal Fatigue Life Prediction of μBGA Solder Joint Using Sn-37mass%Pb Solder and Sn-3.5mass%Ag Lead-free Solder   2001 August;19(4)
e-sciencecentral
Register for e-submission
Register here to access the e-submission system of Journal of KWJS for authors and reviewers.
Manuscript Submission
To submit a manuscript, please visit the Journal of KWJS e-submission management system at http://submit.e-jwj.org, read the Instructions for Authors, and log into the Journal of KWJS e-submission system. For assistance with manuscript submission, please contact: koweld@kwjs.or.kr.
Free archive
Anyone may access any past or current articles without logging in.
Editorial Office
#304, San-Jeong Building,
23, Gukhoe-daero 66-gil, Yeongdeungpo-gu, Seoul 07237, Korea
TEL : +82-2-538-6511    FAX : +82-2-538-6510   E-mail: koweld@kwjs.or.kr
Browse Articles |  Current Issue |  For Authors and Reviewers |  About
Copyright© by The Korean Welding and Joining Society. All right reserved.           Developed in M2PI