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PCBD-Aug2016

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August 2016 • The PCB Design Magazine 37 nologies. However, these technology sectors are continuously in development due to newer ma- terial research and cost pressures to compensate for newer harsh environments than previous designs and/or even legal requirements such as RoHS and/or even local requirements connect- ed to emission either into the air or down the drain. With this all stated, one aspect that is a hot topic—depending on whom you discuss with— is no-clean. From the information that I have obtained over the years, this was a great mar- keting term; however, is not true if you have the perception that no-clean means that assem- bly cleaning is not required. For the bare PCB this may be true; however after you run a PCB via the SMT process, add manually and/or via automated equipment components for a wave soldering process, then perform various manual touch points such as handling for test and/or in- spection, the resulting ionic levels at this point usually do not mean the assembly is clean—yet all materials are "no clean." At this point the challenge is what the next step should be? This would be a challenge that I see coming that the industry will need to understand and what test methods and guidelines should be used and fol- lowed. _____________________________________ Laura Turbini International Reliability Consultant (Chapters 45, 59) Q: What do you really enjoy about the industry? A: I have had the privilege of working in the electronics industry for almost 40 years, starting in 1977 when I joined Western Elec- tric's Engineering Research Center. As one of the early women in the industry, I was treated with respect and support by my many male as- sociates. One thing that always impressed me in my colleagues is the way they worked to- gether and helped each other. Over the years I had a chance to learn from the industry's lead- ing thinkers. The insights I received from them led me into the area of research related to fail- ure modes in printed circuit boards—particu- larly to the study of CAF (conductive anodic filament) formation. "Standing on the shoul- ders of giants" enabled me and my students to identify the chemical nature of CAF and how it is formed. I was first asked by Clyde Coombs to con- tribute to the 4th edition, which published in 1996, and subsequently to the 5th, 6th and 7th editions. The present 7th edition was very im- portant as a central resource for lead-free sol- dering. Writing a technical book chapter took a great deal of time to compose it in a clear man- ner and to make sure there were no errors—but I had learned to do that early in my career when I was the editor of the Western Electric Engi- neer. I am pleased to have been a participant in this book and I hope my former students will pick up where I left off. _____________________________________ Reza Ghaffarian Principal Engineer, Jet Propulsion Laboratory, California Institute of Technology (or JPL/NASA, CIT) (Chapters 60, 61) Q: Why did you de- cide to write two chapters on PCB reliability for the Printed Circuits Handbook? A: Well, when I look back, I find it to be in- teresting, even maybe amusing, as how a simple request by Happy, a dear long-time colleague friend and a co-editor, caused me months of hard work followed by a final proud moment of accomplishment. I am not joking since this for me is another extra activity, only work dur- ing weekend since I have a day job to do and that also put additional burden of as what I can publish. Well, I said OK to a simple request of review and republish with minor modification of a previously written chapter on PCB reliabil- ity. I thought a few weekends would be OK, es- pecially knowing the Christmas holiday of 2014 was on the way. A few weeks became more than six months of nonstop weekend work and now THE AUTHORS OF THE PRINTED CIRCUITS HANDBOOK SPEAK

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