Appeal No. 1997-3979
Application No. 08/586,365
is read on the upper surface of region 61, which at the stage
of production shown in Figure 10 has had the emitter region 89
formed therein. We note that the foregoing limitations also
can be read on the device in the production stage depicted in
Figure 9, i.e., before the emitter region is formed in p-type
region 61. The examiner concedes that claim 8's requirement
that the p-type layer "hav[e] a peak doping concentration
within the p-type layer at less than 700 angstroms from its
upper surface" is not satisfied by Eklund. As evidence of
motivation for forming Eklund's p-type layer with such a
doping concentration, the examiner cites Eklund's disclosure
that the shallower emitter region provided by his invention
permits the use of a shallower base region, thereby allowing
tighter control of a narrow base width (col. 1, lines 26-30)
and yielding a higher performance transistor (col. 4, lines
18-29). In addition, the examiner notes Eklund's disclosure
that the base and collector regions can be formed by
conventional methods (col. 3, lines 59-64). Based on these
suggestions and the fact that Doki's disclosed method produces
a base region having a thickness as small as 340D (Doki's Fig.
13B), the examiner contends it would have been obvious to form
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