Appeal No. 2002-0974
Application 09/332,745
appellants that in considering the prior art we must presume the
routineer is skilled not the contrary. In re Sovish, 769 F.2d
738, 743, 226 USPQ 771, 774 (Fed. Cir. 1985). In this art, the
hypothetical person of ordinary skill, the semiconductor
manufacturing engineer, would be expected to be well versed in
chemistry, engineering and physics. Further, appellants have
conceded in their specification that high temperature heat
treatments have been used in the prior art to reduce the number
density of "crystal originated pits" (COP's) and that epitaxial
deposition of thin, crystalline silicon on the wafer surface has
also been used in the prior art to produce a wafer free from
COP's (see page 2, line 14 through page 3, line 2 of the
specification).
We do not find persuasive appellants' arguments concerning
Asayama et al.'s disclosed cooling rate of "at least 10K/s" after
the growth of the epitaxial layer on the silicon wafer. The
temperature at which Asayama et al. begins cooling, between
1150°C and 1250°C meets the limitation in claim 1 that cooling at
a particular rate is effected "during and/or after" the epitaxial
deposition and when the wafer is "greater than 1000°C." Moreover,
since appellants rapidly cool their wafer for the same reason as
do Asayama et al., that is, to create internal intrinsic
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