Appeal No. 2000-1848
Application No. 08/810,920
that both produce a plasma of a gas to etch a substrate." As
urged by appellants, the reactive ion etching process
disclosed in Katz is different than the dry etching process
utilized by Higashikawa. For instance, the reactive ion
etching of Katz is conducted at a low pressure
(1-3 mTorr), whereas the dry etching process of Higashikawa is
performed at relatively high pressures (0.3 Torr). Hence,
since the apparatus and processes of Higashikawa and Katz are
considerably different, it is incumbent upon the examiner to
factually establish that it was known in the art to employ a
helicon-type etching apparatus, or reactive ion etching, in a
process of the type disclosed by Higashikawa which etches the
photoresist in nitrogen gas. This the examiner has not done.
Furthermore, as pointed out by appellants, Katz provides no
teaching or suggestion that the helicon-type etching
apparatus, or reactive ion etching, can be used with an
etching atmosphere of nitrogen. Katz only discloses the use
of oxygen gas as the etching atmosphere. We find no response
by the examiner to appellants' cogent argument that "there is
no suggestion in either reference to use Nitrogen plasma in a
Helicon apparatus to etch a layer, or to use Nitrogen plasma
-4-
Page: Previous 1 2 3 4 5 6 7 Next
Last modified: November 3, 2007