No, I have not seen a good easy way to inspect BGA spheres.  One thing that
compounds the inspection problem is the reflectivity of the solder spheres.
It becomes very difficult for a pick and place machine's vision system to
accurately define the edge of the sphere (i.e. a circle in 2-D).  One method
to inspect is using oblique light and a low power microscope.

To answer the second part of your question: What should one look for?

a) Missing spheres
b) odd shaped spheres
c) large or small spheres
d) bridges
e) loose spheres

Thanks
Sundeep Nangalia
MCNC
e-mail:[log in to unmask]

-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of HGross1029
Sent: Thursday, April 09, 1998 2:47 PM
To: [log in to unmask]
Subject: [TN] BGA's


Is there a good and easy way to inspect BGA balls ?
Is there a piece of equip. available?
What should one look for ?
thanx...hg

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