Hi Annie, Jerry Hoppke again. You say you baked the boards, did you bake over 212 F for two to three
hours, and store in dry box, or use in six hours or less? If not, they could well contain enough moisture
to cause problems(depends on time of year, where you work, etc.). If moisture is the root cause of pin
holes, your real concern should be delamination, pad lifting, solder balls, and other major issues that
outgassing steam can cause.
annie laberge wrote:
> Hi Earl Moon !
>
> Did you check your G-200 ? We are confident that your solder joints are
> more than perfect !!!
>
> By the way, this pinhole problem as per IPC is within specification but is
> a "non-conforming process indicator"...
> For us, the difference between a pinhole and a blowhole is that a blowhole
> clearly shows that there was outgasing and gas came out of the hole while
> pinhole is only a little hole in the solder.
> Can we say that a pinhole is the same as a blowhole but less critical
> ???...We taught that it was 2 different problems.
> We think that the root cause might be different between a blowhole and a
> pinhole. We baked the boards and still have pinhole...it did not make any
> difference...that is why we think it is not a moisture or gas escape problem.
> Could it be a process issue ?
>
> Annie
>
> At 09:25 AM 1/6/99 -0600, you wrote:
> >Annie,
> >
> >Next to my favorite main board manufacturer (Tyan), Matrox is my (and so
> many others) favorite
> >graphics card maker. To hear you are having these difficulties makes me
> run to my G-200 and check
> >the solder joints, on the one hand, and congratulate you for your honesty
> and courage on the other.
> >
> >I will send you a couple of pretty/ugly pictures as x-sections, if you
> like, showing some
> >possibilities. Moisture may be an issue. Other issues may include glass
> fiber protrusion into plated
> >hole walls (not effectively removed after etch back) acting as a conduit
> for gas escape while also
> >reducing plating thickness below that specified.
> >
> >With that much copper inside the MLB, you and your fabricator might be
> experiencing other problems.
> >For you, as you well know, there is a serious thermal barrier to effective
> solder process
> >management. Plating quality/thickness, or?, may play a part. Other issues
> might include certain
> >laminate conditions as micro voiding or larger than specified voids in the
> thermal evaluation area.
> >However, I would bet you are using a very good fabrication facility that
> could render much help.
> >
> >Are you using quality conformance test circuitry? How do your x-sections
> look as received and after
> >thermal stress?
> >
> >Keep up the good work and I can't wait to see what this product turns out
> to be,
> >
> >Earl Moon
> >
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