Thermal Cycle Testing of PWBs – Surface Finish and PWB Reliability

There are two ways in which metallic surface finishes, on exposed traces and pads, can affect PWB reliability results when tested with thermal cycling. The surface finish can have a direct influence by extending or reducing cycles. There can be a indirect influence where the application of a surface finish requires a high temperature thermal excursion can degrade the interconnection or material which in turn affect cycles to failure.

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