Chemical tests

Potting compounds are often used on printed circuit boards to improve reliability.  In spite of this added protection, adhesive failures, otherwise known as delamination, can occur and lead to substantial problems from moisture ingress.  Root causes of adhesive failures may be surface contaminants, inherently weak bonding between solder mask and potting material or thermal stresses that develop during temperature cycling. In an adhesion analysis a combination of chemical and mechanical tests is often needed to determine the root cause.  Chemical testing includes surface analyses such as XPS and SIMS; both reveal chemical groups available for bonding at the surface.   Contaminants may be revealed during these tests.  Basic tests such as FTIR, TGA and EDS provide information on the …

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