Electronics Forum | Thu Oct 26 13:56:08 EDT 2000 | ptvianc
Hello: Pre-baking laminates should only be performed:(1) to meet contractual agreements or (2) in response to an actual defect that can be traced to PWB water absortion. Besides the fact that a pre-bake is an enormous process "bottleneck," it also
Electronics Forum | Tue Nov 16 18:02:29 EST 1999 | John Holland
What are the main advantages of moving from a 140 degree C FR4 laminate to a higher Tg laminate 180 degree C ?. Would the higher Tg laminate be less susceptable to bow and twist ?. John Holland
Electronics Forum | Mon May 16 22:59:40 EDT 2005 | davef
We believe your problem is caused by the mismatch in CTE of the material ised in your BGA. In fact, this "potato chipping" [where the corners curl-up] is present in all BGA. The issue is the matter of degree. [Mismatching CTE is how old thermostats
Electronics Forum | Thu Feb 03 06:21:57 EST 2000 | Ignacio Simon
I would like to have information about the materials commonly used for laminates of printed circuit boards, their main thermal, mechanical, humidity and electrical characteristics and proper finishing and aplicattions, and advantages/disadvantages be
Electronics Forum | Thu Feb 15 22:55:45 EST 2007 | davef
Questions are: * Is the blistering in the solder mask or the laminate? * If the blistering is in the solder mask, what do the blisters look like [eg, size, quantity, distribution, etc]? * If the blistering is in the laminate, what do the blisters loo
Electronics Forum | Thu Sep 09 19:32:12 EDT 2021 | kumarb
Forgot to ask earlier - what is the TG rating for your laminate? If not selected already, use a high TG rating like TG155 or TG170 laminates for the ROHS temps. Never saw swollen PCBAs with such rated PCBs to date.
Electronics Forum | Wed Feb 21 05:52:17 EST 2007 | Stephen- SMT engineer trainee
Some of the blister in solder mask, normally 1 circle blister(about 1cm in Dim.) in each PCB. In addition, there are also blister in laminate, the also look like 1 circle blister(about 1cm in Dim.) in each PCB.
Electronics Forum | Mon Apr 02 20:47:22 EDT 2001 | davef
Cuppla questions for ya ... Where are the shorts [above the mask or between the mask and the laminate]? On the board, what material is between the copper traces and the mask? What type of solder mask(s) used by your suppliers? What are they using
Electronics Forum | Wed May 28 08:25:08 EDT 2003 | davef
That's what we do [no more than three reworks or mods]. Your "four reworks permissable" was probably based on the 55110 five thermal cycles, counting wave soldering as the first cycle. How do you plan to keep track of each of those rework actions?
Electronics Forum | Sat May 02 08:48:32 EDT 2009 | davef
You have a board defect. Any moisture and/or organic contaminants trapped by the solder resist during lamination may cause solder mask delamination, blistering and/or adhesion loss during subsequent soldering operations or during extended use.
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