This month's PCFab is the annual edition on Laminate suppliers.  It will   
answer most of your questions for you


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From:  TechNet-request[SMTP:[log in to unmask]]
Sent:  Tuesday, June 11, 1996 11:15 AM
To:  [log in to unmask]
Subject:  FAB: BT Resin


Have seen a number of literature articles indicating the standard   
material
for a MCM-L is BT resin.

Question 1: Which laminate material suppliers make BT based resin   
laminates?

Question 2:  With the advent of multifunctionals what properties still   
make
BT resin based laminates the preferred choice?.

Question 3: Do today's BT resin formulations still show the significant
shrink previously reported?

Question 4:  Are there fabrication issues related to fine lines, feed
through holes or lamination that make BT resin based multichip module   
boards
more challenging to the fabricators and thus make them less cost   
effective
when compared to other resin systems of comparable glass transition
temperature?