Lon,
        Don't worry about the PCB finish for BGA's.  They are pretty robust.
We regularly use BGA's on all three of your listed board finishes.  Fine
pitch, microBGA and the use of a no clean process will determine preferred
board finish.

Ryan G.

> -----Original Message-----
> From: Lon Weffers [SMTP:[log in to unmask]]
> Sent: Friday, February 04, 2000 7:37 AM
> To:   [log in to unmask]
> Subject:      [TN] FW: pcb finish with bga
>
> -----Original Message-----
> From:   Lon Weffers [SMTP:[log in to unmask]]
> Sent:   vrijdag 4 februari 2000 11:19
> To:     [log in to unmask]
> Subject:        pcb finish with bga
>
> Dear friends,
>
> We are starting to use bga's on our pcb's.
> I was wondering what the usual board finish should be. HAL, or gold or
> bare
> copper? Ideas and tips for reflow are very welcome, we are new in the bga
> business.
>
> Greetings
> Lon Weffers
> Matas Electronics Bv
> visit us at www.matas.nl
>
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