Joel,

Baking was indeed required for leaded PCBs, the nature of most laminates is
to suck up moisture regardless of the Tg or final finish. Also, depending
upon the laminate type, baking may be necessary immediately upon receipt
from the board supplier. I always caution assemblers to bake boards
regardless, it just makes good sense.

Franklin D Asbell

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Joel Alexander
Sent: Tuesday, October 23, 2007 11:23 AM
To: [log in to unmask]
Subject: [TN] Delamination of lead free PCBs

Has anyone experienced an increase of delamination when processing in a 
lead free environment. Typically 4 to 6 layer pcbs during SMT reflow. We 
are using the high temp laminate suggested for our process. When we 
contacted the supplier and they indicated that any PCBs that are over six 
months old should be baked prior to processing. This was never required 
with leaded PCBs. 

Is anyone seeing the same condition and similar feedback from your PCB 
suppliers



Joel Alexander
Quality Assurance Manager
TT APSCO, INC. 

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