FOD on the lamination press plate is definitely possible.

This was a prototype run so just a couple of panels. 4500 cm^2 of board
total.

We're opening an 8D with our bare board supplier. I'll be sure to post any
additional information or results!

Thank you,
Tom

On Thu, Feb 7, 2019 at 12:26 PM Yuan-chia Joyce Koo <[log in to unmask]>
wrote:

> are those high volume product or just one or two panels?
> jk
> On Feb 7, 2019, at 10:07 AM, Tom Brendlinger wrote:
>
> > Unfortunately I don't have XRF capability in house. I'm hoping to get
> > approval to send it out.
> >
> > Interesting theory Steve. The only thing about that theory that I
> > don't
> > understand is why it would be in the same location on two boards,
> > but not
> > on the rest. It's possible that it was just luck, but it isn't a super
> > satisfying answer. I'll see what analysis I can get approved and if it
> > supports that theory.
> >
> > Thank you!
> > Tom
> >
> > On Thu, Feb 7, 2019 at 7:51 AM Steve Herring
> > <[log in to unmask]>
> > wrote:
> >
> >> Is it possible there was a glass fiber on that area when it was
> >> plated,
> >> leaving you with the original copper foil thickness?
> >> The fiber was then removed prior to ENIG?
> >>
> >> My guess at the cause.
> >>
> >> Steven E Herring
> >> Director of Engineering
> >> Pennatronics Corp
> >>
> >> -----Original Message-----
> >> From: TechNet [mailto:[log in to unmask]] On Behalf Of FTL Quality
> >> Sent: Thursday, February 07, 2019 3:07 AM
> >> To: [log in to unmask]
> >> Subject: Re: [TN] "Wrinkle" on outer copper layer
> >>
> >> Are you able to complete an XRF analysis on the Nickel thickness
> >> of the
> >> ENIG?
> >>
> >> -----Original Message-----
> >> From: Tom Brendlinger
> >> Sent: Wednesday, February 6, 2019 8:36 PM
> >> To: [log in to unmask]
> >> Subject: [TN] "Wrinkle" on outer copper layer
> >>
> >> Hello TechNet,
> >>
> >> I've recently received some boards that have a defect I've never seen
> >> before.
> >>
> >> There is a linear depression in a 2oz outer copper layer on two
> >> out of 45
> >> boards. One of the boards was on a solder sample panel, the other was
> >> assembled with the defect.
> >>
> >> The depression has the appearance of a wrinkle or groove, it is
> >> approximately straight and square to the edge of the board. At its
> >> widest
> >> point it is about 0.006" wide, and as far as we can measure it is
> >> between
> >> 0.0015" and 0.002" deep. There are a couple of small delaminations
> >> nearby
> >> (on a panel that has not been reflowed).
> >>
> >> I looked through IPC-A-600 and did not find anything about this
> >> type of
> >> issue. I don't have the equipment to microsection or x-ray the
> >> board, so
> >> I'm not sure whether the foil is damaged under the plating (Which
> >> is RoHS
> >> ENIG).
> >>
> >> Hopefully this image link works:
> >> https://snag.gy/Kx58Oy.jpg
> >>
> >> Please let me know if you've seen this before or otherwise know
> >> how I can
> >> find more information.
> >>
> >> Thank you!
> >> Tom Brendlinger
> >> Senior Electrical Engineer
> >> Superpedestrian, Inc.
> >>
>
>