Appeal No. 2006-1797
Application No. 09/866,319
of the collector. An overdoped SIC zone is therefore
obtained under the emitter window.
With the above discussion in mind, we find that Marty
teaches a vertical bipolar transistor having an SiGe
heterojunction base of layers into which phosphorous is implanted
in order to overdope the SIC region of the transistor. One of
ordinary skill in the art would have construed this teaching to
mean that the SIC region disclosed in Marty has a narrow vertical
width and a high dopant concentration. Therefore, the ordinarily
skilled artisan would have found such teaching to be equivalent
to the claimed limitation of an n-type dopant region having a
narrow vertical width and a high dopant concentration. We further
find that the qualifying limitation, whereby the vertical width
of the n-type dopant is sufficiently narrow to avoid lowering the
breakdown voltage, and the dopant concentration is sufficiently
high to restrict the base widening when the base emitter junction
is forward biased cannot be relied upon to distinguish the claim
over Marty. The claimed transistor and the one disclosed in
Marty are structurally similar, and they are produced by similar
processes. Additionally, we find that Appellants have merely
provided gratuitous allegations not supported by evidence to
establish a difference between the claimed transistor and
Marty’s. Therefore, Appellants have not effectively rebutted the
Examiner’s prima facie case of anticipation. Consequently, we do
not find error in the Examiner’s stated position, which concludes
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