Browse > Article
http://dx.doi.org/10.6117/kmeps.2015.22.1.043

Ion Migration Failure Mechanism for Organic PCB under Biased HAST  

Huh, Seok-Hwan (ACI Division, Samsung Electro-Mechanics)
Shin, An-Seob (ACI Division, Samsung Electro-Mechanics)
Ham, Suk-Jin (ACI Division, Samsung Electro-Mechanics)
Publication Information
Journal of the Microelectronics and Packaging Society / v.22, no.1, 2015 , pp. 43-49 More about this Journal
Abstract
By the trends of electronic package to be smaller, thinner and more integrative, organic printed circuit board is required to be finer Cu trace pitch. This paper reports on a study of failure mechanism for PCB with fine Cu trace pitch using biased HAST. In weibull analysis of the biased HAST lifetime, it is found that the acceleration factor (AF) of between $135^{\circ}C/90%RH/3.3V$ and $130^{\circ}C/85%RH/3.3V$ is 2.079. A focused ion beam (FIB) was used to polish the cross sections to reveal details of the microstructure of the failure mode. It is found that $Cu_xO/Cu(OH)_2$ colloids and Cu dendrites were formed at anode (+) and at cathode (-), respectively. Thus, this gives the evidence that Cu dendrites formed at cathode by $Cu^{2+}$ ion migration lead to a short failure between a pair of Cu nets.
Keywords
Biased HAST; Organic PCB; Copper; Ion migration;
Citations & Related Records
Times Cited By KSCI : 6  (Citation Analysis)
연도 인용수 순위
1 W. S. Hong, C. M. Oh, N. C. Park, B. S. Song and S. B. Jung, "Reliability assessment for electronic assemblies with electrical and electrochemical properties measurement", Journal of KWJS, 25, 118 (2007).
2 C. H. Hare, "Paint film degradation mechanism and control", Society for Protective Coatings, (2002).
3 F. Franz, W. Ralf and T. Axel, "Diffusion of metals in polymers", Materials Science and Engineering, R22, 1 (1998).
4 B. I. Noh, J. W. Yoon, W. S. Hong and S. B. Jung, "Evaluation of electrochemical migration on flexible printed circuit boards with different surface finishes", J. Electronic Materials, 38, 6 (2009).
5 C. Zhang, P. Yalamnchili, M. A. Sheikhley and A. Christou, "Metal migration in epoxy encapsulated ECL devices", Microelectron. Reliab., 44, 1323 (2004).   DOI
6 Y. H. Chun and L. J. Kwon, "Accelerated life test and data analysis of the silver through hole printed wiring board", J Korean Soc Qual Manag., 25(2), 15 (1997).
7 K. J. Lee, K. S. Kim and K. Suganuma, "Electro-migration phenomenon in flip-chip packages", J. Microelectron. Packag. Soc., 17(4), 11 (2010).
8 K. Suganuma, "Tin whisker growth in vaccum thermal cycling", Presented at 2010 TMS Annual Meeting & Exhibition, February 14-18, Seattle.
9 W. S. Hong, S. B. Jung and K. B. Kim, "Analysis method of metallic ion migration", Journal of KWS, 23, 32 (2005).
10 H. Tanaka and K. S. Kim, "Introduction of reliability test technology for electronics package", J. Microelectron. Packag. Soc., 19(1), 1 (2012).   DOI
11 W. J. Choi, S. H. Yoo, H. S. Lee, M. S. Kim and J. K. Kim, "Effects of hardeners on the low-temperature snap cure behaviors of epoxy adhesives for flip chip bonding", Kor. J. Mater. Res., 22, 454 (2012).   DOI
12 IPC-TM-650, Assessment of Susceptibility to Metallic Dendritic Growth: Uncoated printed wiring (North brook, IL: The iNstitute for Interconnection and Packaging Electronic Circuits, 1985).
13 K. S. Kim, K. J. Lee, K. Suganuma and S. H. Huh, "Effect of Cl content on interface characteristics of isotropic conductive adhesives/Sn plating interface", J. Microelectron. Packag. Soc., 18(3), 33 (2011).