Hi Everyone,

 

We've had a problem lately with fine strands of stainless steel wire
being found on top of some of our .5 mm pitch ICs.  This has caused both
internal and external issues, and we've yet to identify the source.

 

It's definitely formed wire, with a thickness ranging from 7 to 10
microns, and up to 3 mm in length.  

 

Our automated optical inspection stations can only reliably detect
widths of 12 to 15 microns.

 

I've checked the internet in an attempt to find common applications of
this wire.  I've found two, and they were for ultra-fine filters and
stencil screen mesh.  We've investigated (I think) all of our machinery
that would utilize filters this small and have found no such usage.
I've also checked every stencil in our plant, and all of our mesh
material is some type of a plastic compound.

 

Do you have any idea where this stainless steel might be coming from?

 

Any suggestions would be sincerely appreciated!

 

Thanks,

 

Leland


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