Appeal No. 1999-2576
Application 08/836,960
P regions 8a and 10a constitute the collector and emitter
respectively, while N- epitaxial layer 6 constitutes the base.
N+ poly region 24 is separated from base 6 by a silicon oxide
layer 18b, which "prevents diffusion of the of the arsenic
dopant into N- epi region 6 from N+ poly region 24" so that
"[t]he base region of the transistor thus remains N- epi"
(col. 4, ll. 53-56), thereby yielding "a transistor with
breakdown voltages greater than conventional transistors
fabricated such that the N+ poly is in contact with the N- epi
base" (id. at ll. 56-59).
Also, the base contact includes a refractory metal
interconnect 45b supported by a doped polysilicon contact
layer 24, which is separated from the base region 6 by a
diffusion barrier layer 18b of silicon oxide, formed as part
of a grown oxide layer 14 (Fig. 2) (col. 3, ll. 41-52).
While P+ POLY regions 30a and 30b function as the
collector and emitter contacts respectively (col. 4, ll. 47-
49), appellant correctly notes (Brief at 6) that N+ POLY 24
- 6 -
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