Appeal No. 2001-2544
Application No. 08/995,108
temperature of about 190°C (column 5, lines 11-13). It is also
taught that tantalum can replace the titanium nitride. (Column 3,
lines 56-57). The only perceptible difference between Gelatos and
the instant claim is the inclusion of tantalum/tantalum nitride
for titanium/titanium nitride.
The examiner has stated that titanium/titanium nitride and
tantalum/tantalum nitride “stacks” are known equivalents. Our
review causes us to agree with the examiner that, at the time the
invention was made, titanium/titanium nitride and tantalum/
tantalum nitride were indeed well known as equivalent adhesive/
barrier layers.1 Thus, we concur that exchanging Ta/TaN for
Ti/TiN would have been obvious to one of ordinary skill in the
art at the time the invention was made. As stated in In re Fout,
675 F.2d 297, 301, 213 USPQ 532, 536 (CCPA 1982) “Express
suggestion to substitute one equivalent for another need not be
present to render such substitution obvious.”
The appellants argue that Gelatos teaches away from the
present invention by preferring simple annealing at 500°C-600°C
over the lower temperature of 400°C-500°C under forming gas
(Appeal Brief, page 9, lines 7-15). This argument is
unpersuasive for two reasons. First, a reference is available
for all that it discloses and suggests, even nonpreferred
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