I have been using a fr4 type material to make a substrate utilizing
Constantan and Copper  for the metallic layers  for over 10 years. The
thickness of the Fr4 is approx. 50 microns.
There are thinner materials out there , but the handling becomes an issue.
        The only way to process a very thin substrate with out the glass
cloth in it is to modify the component make up of the polymer  to make it
Flexible.

Russ Smith


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From: <[log in to unmask]>
To: [log in to unmask]
Subject: [TN] Thin FR#4 substrate
Date: Wednesday, November 01, 2000 12:23AM

Hi:
     Is there anyone using very thin(thickness) FR#4 substrate instead of
flex
cicruit ? It may be kind of FR#4 without fibre glass enforcement. Any
information are welcome.

regards,

Chan SL

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