Atomic layer deposition (ALD) for environmental protection and whisker mitigation of electronic assemblies

Abstract In this study, we demonstrate how metal-oxide thin-film conformal coatings grown by atomic layer deposition (ALD) can be exploited as an effective approach to mitigate tin whisker growth on printed circuit boards. First, study the effect of different ALD and process parameters Sn–Cu-electroplated test coupons, combining optical imaging scanning electron microscopy evaluating distribution surface. On these samples, found that one important parameter in mitigating is time interval between electroplating coating (pre-coat time), which should kept order few days (2, based our results). Atomic layer-deposited were also toward formation storage conditions. Furthermore, show limiting need for outgassing electronic assemblies (PCBAs), additional stringent requirement applications space industry. Our experimental results thus demonstrated a suitable technique aerospace applications, both terms degassing mitigation.