Appeal No. 2003-1501
Application 09/756,929
We find that Ito is directed to an “apparatus for gas phase treating substrates, in
particular, . . . a large number of substrates in a single operation” (col. 1, lines 7-10, and col. 1,
line 67, to col. 2, line 2). Ito acknowledges that in the prior art, resistance heaters or the like heat
the substrates to a reaction temperature and then plasma gas entering at one end of the reactor
treats the heated substrate, and thus finds that substrates located at different distances from the
plasma gas inlet “makes it difficult to supply active reaction seeds uniformly to all substrates,”
such that “a large number of substrates cannot be treated in a single operation” (col. 1, lines 20-
35; see also col. 1, lines 42-50). Ito’s solution is to form the plasma gas in the batch reactor and
to heat a radiator surrounding the substrate by high frequency power supply means, such that the
plasma gas is formed near each of the substrates, which can be arranged in parallel and very close
to each other, thus resulting in uniformly treating a large number of substrates in a single batch
operation (col. 2, lines 3-31). In an embodiment, “heat is radiated to heat silicon wafers 101 to a
temperature of about 1000°C. at their centers,” which is “as uniform as when heated by a
conventional electrical resistance heater” (col. 3, lines 35-41). Ito states that the methods and
apparatuses can be used for different plasma treatments, wherein the “radiators heated by a high
frequency power supply means and for heating wafers may be provided either outside the
reaction tube or inside a reaction tube,” with either arrangement providing “uniform treatment of
a large number of wafers in a single operation” (col. 5, lines 3-35).
We determine that contrary to appellant’s arguments, the disclosure of Ito taken with the
disclosure of Rigali provides substantial evidence supporting the examiner’s position that one of
ordinary skill in this art would have modified the apparatus of Rigali by adding radiators heated
by high frequency power supply means, such as an energy field generator, inside the process unit
as suggested by Ito, in the reasonable expectation of providing temperature control in order to
treat a large number of substrates in a batch operation, the heat generated being sufficient to cure
plastic encapsulated electronic packages when used as the substrate. Indeed, in view of the
disclosure in Ito that the apparatus and methods disclosed therein are applicable to plasma
processing generally as the examiner points out, we also cannot agree with appellant’s argument
that the references are not combinable because of differences in the plasma treatment described
in the preferred embodiments. Furthermore, we agree with the examiner that the apparatus of
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