Appeal No. 2001-0445
Application No. 09/017,338
the cause of poor bonding to palladium surfaces at
temperatures below 200°C because hydrogen makes the
plated palladium material surface harder. The present
invention is known to release this hydrogen while
preventing oxidation of the palladium surface during
heating and prior to bonding a wire to the palladium
through the gold. Furthermore, successful bonds using
gold wire of 0.001 inch diameter have been made using
the present invention without heating the palladium
layer above 200°C.
Hence, according to appellants' specification, the second, or
gold, layer must be less than about 200 Angstrom thick for the
hydrogen molecules to satisfactorily pass therethrough. On the
other hand, Makoto is silent with respect to the thickness of the
second gold layer and, as noted by appellants, the figures of the
reference depict the gold layer as essentially equal to the
thickness of the copper and platinum layers. Although Makoto
heats the circuit to a temperature of 430°C for six minutes, the
examiner has not established that such heating would inherently
or necessarily result in the first metal layer being
substantially free of hydrogen molecules. It is well settled
that inherency requires inevitability, not merely possibilities
or probabilities. In our view, there is insufficient evidence of
record to support the conclusion that the first metal layer of
Makoto is substantially free of hydrogen, as required by the
appealed claims.
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