|Ask the Experts|
May 14, 2007
I have heard of tin whiskers creeping along the surface of a PCB under paralyene. Would vacuum impregnating potting 100% mitigate this disposable assembly?
|Expert Panel Responses|
Unfortunately, your terminology is slightly confusing. Tin whiskers can penetrate paralyene. On the other hand, if the interface is weak, it may seek a more preferential path under the paralyene. If the interface is weak, vacuum impregnation would likely have minimal effect unless it places the paralyene under stress. But, you then risk damage to your components.
CEO & Managing Partner
Vacuum would help but will not prevent it. The only way to prevent whisker growth under any condition is to remove the driving force, which is the compressive stress, from the Sn coating. This can be done quite effectively by using the thin Sn (<3 um When there is a large external applied (regardless intentional or non-intentional) compressive stress, it could induce whisker growth in the Sn layer also - it is a matter of time.
Cookson Electronics, Enthone
I am not an expert on Tin Whiskers, but everything I have read or been told by experts is that there is no method to 100% guarantee that Tin Whiskers will not develop. There is detailed information on the iNEMI and many other web sites.
|Submit A Comment|
Free Newsletter Subscription
Circuitnet is built for professionals who bear the responsibility of looking ahead, imagining the future, and preparing for it.
Insert Your Email Address