Sasportas,
   Be very careful when using the " BLACK PAD " scenario.   Audience can run
with this information
an make a mountain out of a mole hill.   What is the suspected failing mode?
How was this identified
and/or confirm.   If this is an ENIG process BGA, what reflow temp and how
many were subjected.
Reflow temps can lead to a thicker IMC region with nodules resulting in a
marginal BGA strength.
You will have to conduct BGA fault isolation and a series of analysis to pin
point the failing mechanism.

victor,

-----Original Message-----
From: Marki Sasportas [mailto:[log in to unmask]]
Sent: Monday, July 22, 2002 7:04 AM
To: [log in to unmask]
Subject: [TN] Au-Ni coating


Hello All,

I have problem in BGA rework, In some cases after, heating specific zone on
the board ( gold finish)
A near BGA joints are being defected. After taking off this BGA I noticed
that some of the pads are black,
What can cause the problem?

Thanks in advance,
Sasportas Marki,
CreoScitex Corporation Ltd.

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