Folks,
During some of my consulting efforts, I have had some interesting conference
calls recently. I am finding now, as some time before but not really
noticing, that some Asian PCB shops do not use 2113 or 2313 glass style
materials. They do use a lot of 1506 types (about 6 mil thickness with a
relatively low resin content approximating 7628) we do not use in the US.
What makes this particularly interesting is my need to transfer MLB
technology to Asian shops.
As one example, for some hi-rel board types I designed using, of course,
DFM/CE and my TABLE II in my book, I needed to get concurrent with the
supplier selected by our Asian cuatomer. Our Asian customer needs a "local"
shop to do their boards now that we have proven they work very well.
Anyway, we had several conference calls with our customer's potential new
supplier and found issues with the above mentioned materials, the initial
quality and long term reliability issues as well as impedance requirements
to be an interesting study in concurrent engineering. For hours we discussed
some basic and advanced isses and are proceeding rather well though I never
knew this gap existed between them and us.
Part of what came out the telephone meetings is the following table I
created many years ago and I use with all my clients to ensure the highest
initial and long term reliability MLB's at a good price:
TABLE II
POD Laminate Material
Core Chart For Dimensional Stability,
MLB Laminate Integrity, And Impedance Control
REQUIREMENT
PREFERRED NOT PREFERRED
PREG THICKNESS/" GLASS STYLE/% RESIN - SINGLE PLY
0.0017
106 (75%)
0.0025
1080 (65%)
0.0035
2113 (58%)
0.0045
2116 (55%)
0.0070
7628 (44%)
DIELECTRIC THICKNESS/" GLASS STYLE - MULTI PLY
0.004 106, 2113 1080,1080
0.005
1080, 1080
0.006 1080, 2113 106,106,106
0.007 1080, 2116 7628
0.008 2113, 2113 1080, 2113, 1080
0.009 2116, 2116 1080,2116,1080
0.010 2116, 2116 1080,2116,1080
0.011 2113, 1080, 2113 106,7628,106
0.012 1080, 7628, 1080 2113,2113,2113
0.013
2113, 7628, 2113 7628,7628
0.014 2113, 7628, 2113 7628,7628
0.015 2113, 7628, 2113
0.016 2113, 7628, 2113 or use 2116,7628,2116
I've also incorporated some changes to the table as part of the continuous
improvement process. These changes, for you having the MoonMan DFM/CE book
should be made to your TABLE II.
I'm interested in any comments regarding material types worldwide and what
others are using relative to TABLE II. Having been in this awhile, I realize
everyone has their way of doing things and using whatever they want - within
the limits of quality and reliability standards.
MoonMan
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