I have to agree with Earl.  Also there are the personnel and economic
restrictions that dictate how far up the food chain a PCB supplier can go to
exchange information.  We exchange information with our leading edge
customers and with our laminate suppliers.  When our customers tell us what
they need in regard to laminate performance and we take this information back
to the laminate manufacturers, we get responses such as the OEM's don't want
to pay for it.  Look at the cost of Thermount (non-woven aramid) materials
and Quartz polyimide when it comes to CTE issues.  It seems like component
manufacturers respond to the needs of OEM's regardless of the cost of the
substrate required to match the components performance.  How does that old
saying go? "You can't have your cake and eat it too"!  Just some food for
thought. :-)

Scott A. Bowles
Engineering Mgr.
Sovereign Circuits Inc.

In a message dated 10/4/99 5:34:37 PM !!!First Boot!!!, [log in to unmask]
writes:

<< One most outstanding memory dates to the transition time from 50 mil pitch
 to 25 mil SMT. A very large, "high technology" board shop, among others,
 said there would never be a way to print and etch patterns for such
 requirements. This was in 1986, I believe. The same conversations occur
 today, as they did then and ten years prior, about what next is impossible.
 However, there are many more astute, real process engineers working in the
 PCB fab arena these days. Only trouble is there so "busy" reacting to, or
 developing new, processes for us to discover.

 And on it goes,

 Earl Moon >>

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