Appeal No. 2005-0585
Application No. 09/821,478
The examiner further states that appellant’s argument that
Tao does not teach reducing the bias between nested and isolated
features, is unconvincing because it is not possible to etch one
without etching the other. The examiner states that appellant’s
selective reading of Tao’s teachings leads to incorrect
conclusions, and states that Tao’s Figs. 3-5 are similar to
instant Figs. 2A-2B. The examiner states that it would be
misleading to suggest that the instant invention is directed to
the trimming of an isolated line based on instant Figs. 2A-2B.
Answer, page 10.
The examiner states that Ma, admittedly, does not address
gate CD control; but is directed to an analogous problem;
namely, linewidth variations in conductor lines in nested and
isolated features, when using photoresist masks. The examiner
states that the etching process is the same as that of the
instant invention, using oxygen reactive ion etching (O-RIE).
The examiner states that the phenomenon of space charge effect
in etching a metal and polysilicon are the same is evidenced by
comparing Ma (col. 2, lines 8-21) and the instant specification
(instant specification: p.13, lines 9-18). The examiner states
that both describe the charge build up and lateral etching of
the layers above the conductor layer. The examiner states that
Ma compensates for the space charge effect by adjusting the RF
frequency of the RIE unit (Ma: abstract). The examiner states
that a person of ordinary skill in the art would recognize that
etching conductive underlayers such as polysilicon gates, would
pose the same problems as Ma’s etching of nested and isolated
metal lines. The examiner points out that Ma and Tao are both
related to device fabrication by the same lithographic
processes, and states that appellant has selectively interpreted
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