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edfas.org 51 ELECTRONIC DEV ICE FA I LURE ANALYSIS | VOLUME 23 NO . 2 GUEST COLUMNIST of legal experts on retainer, the resources are always avail- able, and a staff of highly trained FA specialists can be maintained. If you are fortunate enough to have in-house FA capability you know that its easy availability makes it very popular, and the drawback to easy access is that queue times become an issue. For many organizations, FA is contracted to independent labs on a case-by-case basis. Such labs do excellent materials analysis work and screening analyses such as MIL-STD-1580. It stands to reason that FA labs outside the manufacturer’s umbrella do better with material and chemical evaluation than electrical troubleshooting because electrical schematics, custom test resources, andmanufacturing details are not available. Manufacturer labs, with their detailed knowl- edge of the devices, do much better at troubleshooting functional failures. However, few are willing to invest the time and expense in troubleshooting a cold temperature failure in a five-year-old device for a customer who buys a small number of units per year. I’m sure none of the preceding discussion is a revela- tion to anyone in the field. The most significant issue at hand is the poor communication that exists between the customer and the FA lab. As a customer, it is our responsi- bility to communicate as much detail about the failure as we can. If you send a failure symptom that simply states “IC37 bad” I must inform you that you are part of the problem. Give the FA lab as much detailed symptomatic information as you can, and it wouldn’t hurt to include some failure history if this is a problem you have seen before. Another good step to take is tomake sure you have a strong line of technical communication between your organization and the FA lab. Be a teammember, check in frequently and ask questions. Let them know your needs and what information is important to you. If you can add collaborationbetween you and the FA lab into the analysis process, you will see much better results. FA labs, you are not blameless here either. Too many times I see a task-oriented cookbook approach taken to failure analysis, where each analysis task is passed to I ’ve had the good fortune to have lived in two worlds, having spent a number of years in the failure analysis (FA) lab working for semiconductor manufacturers and also having spent additional years in the aerospace industry. (Pleasedon’t askmehowold I am.) After youhave seen both sides of the electronics industry, as a supplier and customer, it sheds a lot of light on how the two sides interactwith eachother. My personalmoment of epiphany camewhen I realized that I amnow the irritated customer that gave the younger Me such angst. This mademe want to sharewithmy former compatriots in the supplier world how the failure analysis process is perceived from a cus- tomer’s point of view. On the manufacturer side, FA resources are focused primarily to identify process defects, potential reliability shortcomings, and design issues so they can be corrected beforeproduct is released to themarket. Because thereare far fewer options for corrective action on a product that has already left the factory, the percentage of FA capacity dedicated to customer returns is typically small. Meanwhile on the customer side, the FAprocess largely becomes an applications issue. For example, you want to knowwhy “deviceU3” keeps failing in yourmotor control- ler that will be installed into a communications satellite even though the boarddesign and operating environment seemcorrect. It can alsobe a real struggle for the customer to interpret what is found in a typical FA report. Perhaps you want to know if that single yellow dot in the CSAM acoustic microscope map of your microcontroller really points to a reliability concern in the blood sugar sensor your company produces. After all, it says “FAIL” in red letters next to the image in the report, right? And does a 1.1% nickel content in the lead finish really cause a reli- ability problem when the data sheet says that it should be 1.0%? As a customer, you want to ensure that your products are robust. With this in mind, where do you turn for FA? Some larger organizations fund their own FA labs, so the work can be done in house. This is akin to having a team FAILURE ANALYSIS FROM A CUSTOMER POINT OF VIEW Ted Kolasa, Northrop Grumman Space Systems ted.kolasa@ngc.com