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78 The PCB Magazine • July 2017 clusion reached from the data was interesting, with the suggestion that solder joint reliability isn't the problem, but rather component func- tional integrity. Dave concluded by stating that the solution is an emphasis on component se- lection and producibility addressing the func- tion requirements of either thermal transfer or electrical ground characteristics. Industry Consortium Work: How Collaborative Projects Help Your Organization Jack Fisher, project facilitator of the High- Density Packaging User Group (HDPUG) pre- sented next on a Collaborative Approach to Reli- ability Assessment. HDPUG is a project oriented industry consortium addressing the integration of new electronics component packaging and interconnect technologies into member compa- ny supply chains. Their mission is to drive in- novations in the electronics industry, with over 50 electronics industry companies participating in the group. Jack reviewed the status of a cou- ple current projects: Multiple Laminations, led by Ivan Straznicky of Curtiss-Wright, and the Optical Interface Phase II Project, led by Brice Achkir of Cisco, and M. Immonen with TTM. Jack concluded with the results of the recent- ly closed Electro-Chemical Migration project, led by Mike Bixenman of KYZEN Corp. Signifi- cant data, information and results were shared on each of the projects. Mitigation of Pure Tin Risk by Tin-Lead SMT David Pinsky, senior fellow with Raytheon Company reviewed the results of an industry round-robin study on components with pure tin finished terminations that are at risk for tin whisker growth and potential unreliability. The goal of the study was to evaluate the conditions under which typical SMT components will achieve self-mitigation, and a DoE was devel- oped. Many potential factors for consideration were considered for inclusion in the study, and the four factors that were selected were 1) Com- ponent packages (16 P/Ns); 2) Board finish (OSP & SNPb HASL); 3) Pad size; and 4) Manufactur- ing processes. David reviewed the DoE specifics, data and results, including the results of new boards (6−13 months old) and older boards (>5 years old). David presented the conclusions of the DoE, which included 1) Undersides of leads will be mitigated more often than upper sides of leads; 2) Opportunities exist for enhancing self-mitigation through process adjustments; 3) Parts outside of normal shelf life cannot be as- sumed to self-mitigate in the same manner as parts within normal shelf life. ENEPIG—Impact of Surface Finishes and No-clean Fluxes Bill Fox, materials and process assoc. engi- neer with Lockheed Martin Company present- ed on the reliability of ENEPIG in small solder joints. The premise of Bill's discussion was that HDI drives finer features on the printed board, and as solder joints become smaller, HASL be- comes problematic. Electroless Nickel/Electro- less Palladium/Immersion Gold (ENEPIG) is a surface finish that has been demonstrated to have a variety of benefits, however, there are concerns that palladium above a certain thick- ness or content has an adverse effect on the sol- der joint. Bill reviewed the specifics and results of a number of experimental procedures that were developed to test for a number of condi- tions. The conclusions noted were 1) No notice- able extent of PdSn 4 intermetallics in joints due to the lower Pd thickness of the ENEPIG specifi- cation; 2) Solder joints on ENEPIG demonstrat- REVIEW OF THE 2017 IPC RELIABILITY FORUM Figure 7: David Pinsky, Raytheon.