Appeal No. 1998-1728
Application 08/397,243
Thus, Satou discloses that “separately distributed” metal silicide grains exist in the fine mixed structure
and are to be avoided even though the reference does not quantify the amount of such “independently
existing” grains as in the appealed claims and appellants’ specification (e.g., page 10).
We further find that, as pointed out by the examiner (answer, page 4), Satou teaches that the
generation of particles during sputtering can be further reduced when the average grain size of the metal
silicide phase is desirably from 2 to 15 µm and preferably from about 5 to 10 µm (col. 8, lines 43-48),
and the maximum silicon grain sized is preferably 20 µm or less, with the average silicon grain size
preferably 2 to 10 µm (col. 9, lines 21-22 and 26-28). Satou reports in Table 2 that in Satou Example
1, the average grain size of the metal silicide grains is 2 µm and of silicon grains is 7 µm. It is apparent
that the preferred grain sizes of metal silicide taught by Satou and the metal silicide grain size reported
for Satou Example 1 fall within the corresponding limitation of claim 1. The average silicon grain size
reported for Satou Example 1 would reasonably appear to include free silicon grains having a maximum
size of 20 µm or less as specified in claim 1, and thus the reported and preferred silicon grain sizes fall
within the corresponding limitation of claim 1.
We also find that Satou teaches that “there is a relationship between the density of the target
and the quantity of the particles generated” such that “it is desirable to achieve a relative density of more
than 99%” (col. 13, lines 3-9), and reports a density of 99.8% for Satou Example 1 in Table 2. While
there is no claim limitation corresponding to the density of the fine mixed structure, appellants disclose in
their specification that “the density ratio of the target is not less than 99%” and “preferably not less than
99.8% over the entire target” (page 16) as shown for specification Examples 1-10 as reported in
specification Table 2, which latter value is that reported for Satou Example 1. We further find that Satou
reports in Table 2 thereof that the “number of particles generated from the target” (col. 19, line 35)
prepared with Satou Example 1 is “12” (cols. 19-20), which value falls within the range of “Number of
Particles (Pieces)” formed with the targets of specification Examples 1-10 as reported in specification
Table 2.
Satou further teaches that in preparing the fine mixed structure, the powders are uniformly
mixed together with the silicon/metal atom ratio of about 2.0 to 4.0, wherein “it is preferred to use metal
powder of a maximum grain size of 10 µm or less and [silicon] powder of a maximum grain size of 30
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