I'm don't think it makes sense to specify a class 3 annular ring requirement (1
mil annular ring) just because you have a high reliability application.  My
feeling is class 2 with some breakout allowed (provided minimum spacing to
adjacent line is OK and line entry to land is adequately flared) will last
forever for 99% of applications.  A class 3 annular ring only makes sense for
some kind of application (military?) which sees huge temperature swings.   By
blanket specifying class 3 for a commercial/ordinary application because you
want high reliability, you are getting overkill on the annular ring requirement
and unnecessarily impacting manufacturability.

Jonathan Whitcomb  IBM Endicott   607-757-1326   [log in to unmask]
Dept T49G bldg 257-2  1701 North St.  Endicott NY 13760   aisle H office X013
pager 2930  fax 607-757-1156

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