Appeal No. 96-1583
Application 08/066,618
active base regions 64", it is clear from the context of the
referenced disclosure that the lower energy implantation is
not used to form the active base region 64. In the paragraph
bridging columns 14 and 15 of Zdebel, the reference teaches
that, preferably, less than ten percent of the low energy
implantation
penetrates into the epitaxial silicon region 68. As described
at column 15, lines 11 et seq. "[t]he purpose of the shallow
oxide implant is to completely saturate that portion of oxide
110 near silicon-oxide interface 68B with boron so that out-
diffusion of boron from region 68 into oxide 110 across
interface 68B is inhibited, so that the deep boron implant
remains in silicon region 68 and accurately determines the
doping and Gummel number of base 64." Manifestly, the
predominant portion of the low energy implantation is located
in screen oxide 11 at or near interface or surface 68B between
oxide 110 and layer 68 (column 14, lines 10-13). It is the
deeper, high energy implantation of Zdebel that "substantially
determines the Gummel number in base 64" (column 14, line 17),
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