George,
               Single ply construction has become a market driven
          decision for awhile now. With the PCMCIA at single ply
          106 for 6 lyr. (.002 dielectrics)
          Next came .004 - .005 linewidths on innerlayers that forced
          single ply to achieve 50 Ohm transmission lines.
          Some outerlayers combinations also dictate this requirement.
          (No other way to get there)
          Dimensional Stability is different that what most fab shops
          are accustomed too. 2 ply construction yields different
          results due to weave combos and nesting of weaves.
          The attitude has changed about what the volumn of resin is
          required in order to adequately fill etched circuitry areas.
          We're being very successful at this single ply construction
          issue. 10 years ago I would have said impossible. Now I'm
          doing it!

          Green Laminate - My only experience with this term is in
          regards to undercured laminate. This is basically an issue
          of the past. (Possibly unfounded) With todays modern PLC
          controlled presses I have not recently found this to be
          an issue.

          I'm not familiar with the bromide issue. (Educate me)
          94 V0 has always been the target. Has it always been
          necessary? That sounds like a UL question or for a
          OEM consensus / consortium.

          Dave Hoover
          Senior Process Engineer
          Hadco Tech Center Two/Watsonville, Ca
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