Tony

In all probability you will not encounter any problems.

A true conformal coating will have a Youngs Modulus that should make it
"squausshy" enough not to exacerbate CTE mismatch. BTW, squausshy is a new
technical term :-)

As you are using a silicone, it is almost certainly sufficiently "squausshy"
enough - there's that term again!

David is quite right to caution you about trapped air but as you are dip
coating, I would assume that this will not be an issue unless you are
dipping too fast in and out - for general guidance, <12"/min in and <6"/min
out.

Regards
Graham Naisbitt

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> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]]On Behalf Of Tony Whitfort
> Sent: Wednesday, January 24, 2001 10:07
> To: [log in to unmask]
> Subject: [TN] Conformal Coating BGA
>
>
> We are dip coating a product with a BGA part on it.
>
> I am concerned that the coating under the BGA may cause reliability
> problems due to thermal expansion.
>
> We are using a silicon based coating and the BGA part is a standard
> 1.27mm pitch.
>
>  Can anyone point me to some literature on this.
>
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