Title :
A study on solder-joints fall-off failure of electroless nickel/immersion gold pad
Author :
Wan Zhonghua ; Zou Yabing ; He Guanghui ; Luo Daojun
Author_Institution :
Reliability Res. & Anal. Center, China Ceprei Lab., Guangzhou, China
Abstract :
Solder joints which had fell from the electroless nickel/immersion gold (ENIG) pads during the assembly process after reflow were studied in this paper. In order to probe the root cause of the failure in solder joints, cross section and Scanning Electron Microscopy/Energy Dispersive X-ray (SEM&EDS) techniques were applied. In addition, solderability test was also put forward to verify the failure phenomenon. Results showed that, because of the serious corrosion of Ni layer on pad, the interface intermetallic compound (IMC) layer of test samples formed badly, which resulted in the insufficient mechanical strength of solder joints and caused crack or fell off. The Ni-corrosion resulted from poor ENIG process.
Keywords :
X-ray chemical analysis; corrosion; electroless deposition; failure analysis; nickel; reflow soldering; scanning electron microscopy; solders; EDS techniques; ENIG pads; Ni; Ni layer; SEM techniques; corrosion; cross section; electroless nickel-immersion gold pads; energy dispersive X-ray techniques; failure phenomenon; interface IMC layer; interface intermetallic compound; mechanical strength; reflow; scanning electron microscopy techniques; solder joints failure; solderability test; Corrosion; Electronics packaging; Gold; Nickel; Soldering; Surface cracks; Surface morphology; Ni-corrosion; electroless nickel/immersion gold (ENIG); solderability test;
Conference_Titel :
Electronic Packaging Technology (ICEPT), 2013 14th International Conference on
Conference_Location :
Dalian
DOI :
10.1109/ICEPT.2013.6756588
