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60 SMT007 MAGAZINE I JUNE 2025 electrical shorts caused by whisker growth. Among the most effective coatings are Parylene C and silicone, which have been shown to sup- press whisker growth. In contrast, acrylic coat- ings are generally less effective because of their lower hardness. Harder coatings perform better because they require greater force for a whisker to penetrate, making it more difficult for whis- kers to spread and create shorts. e International Electronics Manufactur- ing Initiative (INEMI) recommends specific board finishes to reduce the risk of whisker formation from the copper surfaces of the cir- cuit board. ese include nickel palladium gold (NiPdAu), nickel palladium (NiPd), electroless nickel immersion gold (ENIG), and nickel gold (NiAu). Alternatively, man- ufacturers can use matte tin finishes, pro- vided they apply a plating thickness of at least 6 microns (µm), as thinner plating is more prone to whisker formation. ere are also several manufacturing tech- niques to mitigate whisker growth, including modifications to the annealing process, which involve repeated heating and cooling, as well as the addition of elements such as copper and nickel to solder alloys. Historically, lead was used to slow whisker growth in tin-based sol- ders. However, with the implementation of lead-free regulations, alternative approaches have become more prominent. e GEIA-STD-0005-2—a standard for mit- igating the effects of tin whiskers in aerospace and high-performance electronic systems— provides a framework for developing a tin whisker risk management plan. e standard defines three control levels, each offering vary- ing degrees of mitigation: Figure 3: Enhanced lighting techniques, such as right- angle lighting and high magnification, improve the chances of detection.