It would be worth having your pcb supplier measure the plating thickness,
too thin and you see soldering problems.
Best Regards
ian
>From: Francis Lai <[log in to unmask]>
>Reply-To: "TechNet E-Mail Forum." <[log in to unmask]>, Francis Lai
><[log in to unmask]>
>To: [log in to unmask]
>Subject: Re: [TN] Sloder bubbles on the VIAs
>Date: Wed, 14 Jul 1999 21:49:08 -0700
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>X-To: "Tempea, Ioan" <[log in to unmask]>
>
>"Tempea, Ioan" wrote:
>
> > Hi,
> >
> > now that the problem with the blistering solder mask is fixed ( we sent
>the
> > boards back since backing them was of no use), I have another one.
> >
> > Some of our assemblies have a high density of VIAs. On these products,
> > pretty often we get after wave some solder bubbles over the VIAs, some
>of
> > them exploded, like degassing. Since on some we see the same bubbling
>even
> > on the fiducials, I wonder if the humidity is the only one to blame, I
>even
> > wonder if there's any issue related to humidity at all.
> >
> > So, what could it be? Incompatibility between flux and solder sounds
> > possible?
> >
> > I would appreciate any input,
> >
> > Ioan
>
>Dear Ioan :
>
>To me it sounds like copper plating problem. The surface of the base copper
>probably was not cleaned enough, it caused blisters. I think if you do a
>tape
>test after copper plating, probably, copper plated will peel.
>
>Please correct me if I am wrong!!!
>
>Francis
>
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