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JULY 2019 I SMT007 MAGAZINE 59 plies nominal power to the samples and some expected output is measured over the course of 500 or 1,000 hours to get the best possible idea of what to expect in a normal field service envi - ronment. This is as close to the rubber meeting the road as you can get because this is 100% representative of your full process. All of the testing you've done to this point should give you an idea of what to expect from this type of testing . If you've made good decisions up to THB, you should see very good results. These are the basic blocks of testing that I recommend at a minimum to cover, assess, and increase reliability. Of course, this doesn't cover every test you might need to consider. If your product is an under-hood application, you may need to add a vibration test. If it's going into a harsh environment, you may con- sider a mixed flow gas test. The list of appli- cable tests might grow, or you might be good with some of the basics I have mentioned here, but testing everything on the way to your final product is always a better strategy for reliabil- ity than having to react to the F word. SMT007 Eric Camden is a lead investigator at Foresite Inc. To read past columns or contact Camden, click here. Goepel electronic offers test and inspection solutions for electronics production in automotive suppliers and auto- motive companies. The company specializes in automated optical inspection (AOI), automated X-ray inspection (AXI), and solder paste inspection (SPI) systems for electronics production as well as JTAG/boundary scan and end-of-line test systems. In this interview, Barry Matties catches up with Matthias Müller to talk about Goepel electronic's overall business, the trends that he is seeing in the electronics manufactur- ing industry, and the informative webinar series produced by the company to help further educate their customer base and promote technical discussion on a number of topics. To read the interview, click here. Goepel electronic Solutions, Webinar Series, and Trends failures related to electrical leakage or electro- chemical migration. There are many ways to perform extractions for IC analysis, but one of the most important things to remember is that contamination is not evenly distributed across the entire surface of the assembly. Historical testing using resistivity of solvent extract (ROSE) as well as standard IC extrac - tions will show a result as if the contamination is indeed the same over each square inch. Each soldering process will introduce its own chemi- cal signature into the final level of cleanliness, and only by looking at much smaller areas of the board will you know for sure what each pro- cess brings to the table. There are many ways to do localized extractions, and each has a unique set of benefits and drawbacks, so each method should be examined to determine which is right for your specific application. When you know just how much residue each process is adding, you can then directly address that part of the process to optimize and reduce the amount of active contamination. Excessive active residues will easily absorb atmospheric moisture and facilitate electrical leakage. The next test I always recommend is ther - mal, humidity, and bias (or THB) testing. This process involves placing fully assembled prod- uct into an environmental chamber at elevated heat and humidity with a fixture that sup-

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