-----Original Message-----I'm learning about laminate materials and read with interest several recent tecnet emails on the subject.
From: [log in to unmask] [mailto:[log in to unmask]]
Sent: Tuesday, March 26, 2002 10:05 PM
To: [log in to unmask]
Subject: [TN] another materials question
I'd like to submit a question about a particular construction that is a challenge with respect to registration.
The construction is all 2 core and 3 core. The prepregs are 1-106 and 1-1080, which I have learned are described as resin rich. The construction is balanced with respect to copper weights, glass styles, core thicknesses, and prepreg openings.
What I am observing with this part is variation in how much certain cores shrink, lot to lot,
and variation that I would describe as a shift or possibly a rotation in some of the internal layers.
Am I correct in assuming that these thin cores and these particular prepregs will contribute to lower yields due to misregistration? If anyone would care to offer up ideas on how to tackle the registration challenge that I am observing on this kind of construction, I would appreciate hearing your ideas.
Mark J.