Appeal No. 1998-1728
Application 08/397,243
and submit, in this respect, that Satou does not recognize that the number of such grains should be
limited but rather specifies “the average number of the coagulated
[metal silicide] grains in order to suppress the particle generation,” citing Satou, col. 8, lines 37-38
(brief, pages 4-7). We are not convinced by this argument that the claimed and prior art targets are
distinguishable based on the cited disclosure of Satou.
As we have discussed above, appellants’ claims and specification and Satou both describe the
same characteristics of the fine mixed structure of the target with the sole exception of the number of
the metal silicide grains, said grains being described by Satou as “separately distributed” in a “linked
structure,” and by appellants as “independently existing” in a “chain” structure. Based on the disclosures
in appellants’ specification and in Satou, we find that the “structure” in each instance are the same.
Indeed, we find no disclosure in Satou with respect to “coagulated” metal grains as discussed by
appellants (brief, page 6), which would have presented a different characterization of the silicide metal
grains in the “linked structure” to one of ordinary skill in this art. The whole of that part of Satou which
includes lines 37-38 of col. 8 relied on by appellants, reads as follows:
[T]he size of [metal silicide] depends on the diameter of the metal grains forming the
metal silicide. However, most of the metal grains are coagulated so that [metal silicide] grains
of different diameters are produced. An increase in the variation of the range of grain
diameters causes projections and recesses on the eroded surface from sputtering to become
significant. Because of the increased variation in the surface level, the number of particles
generated increases. For this reason, it is necessary to use uniformly sized grains, and it is
desirable that the average grain diameter of the [metal silicide] phase be from 2 to 15 µm and
preferably from about 5 to 10 µm. [Col. 8, lines 35-48; emphasis supplied.]
We are of the view that one of ordinary skill in this art would have read this disclosure of Satou with the
further disclosure in the reference with respect to the process used therein, that
the grain sizes of the two powders significantly affect the grain sizes of the synthesized [metal
silicide] and [silicon] dispersed between the [metal silicide] grains. In order to provide a
minute structure, it is preferable to use metal powder of a maximum grain size of 10 µm
or less and [silicon] powder of a maximum grain size of 30 µm or less. [Col. 13, lines 55-
61; emphasis supplied.]
Thus, we find that one of ordinary skill in this art would have reasonably expected from the teachings of
Satou to prepare a fine mixed structure having preferred uniformly sized metal silicide grains of from 2 to
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