Appeal No. 2005-2351
Application No. 09/904,112
teaching in the reference that the lower electrodes 54 become
oxidized due to the tantalum oxide layer 55 being crystallized
(Brief, page 7; Reply Brief, page 3). Appellants also argue that
the need for choosing ruthenium oxide as the conductive oxide
electrode negates anticipation (Brief, page 7; Reply Brief, page
2).
Appellants’ arguments are not persuasive. Kunitomo is
directed to an information storage capacitor used in DRAM cells
where the capacitor includes a lower electrode 54 and an upper
electrode 62 consisting of a capacity insulating film 61 and a
titanium nitride film (abstract). The capacity insulating film
is inserted between the first and second electrodes and is a
multi-layered film comprising two or more tantalum oxide films
each having a polycrystalline structure (col. 3, ll. 39-51; col.
4, ll. 18-22). Kunitomo teaches crystallization of the tantalum
oxide insulating film to achieve a high dielectric constant film
and reduce leakage current (col. 2, ll. 33-56; col. 3, ll. 59-
60). The manufacturing method for the capacity insulating film
comprises the steps of (a) forming a first tantalum oxide film by
a chemical vapor deposition (CVD) method; (b) crystallizing the
first tantalum oxide film by a first heat treatment, thereby
forming a first polycrystalline tantalum oxide film; (c) forming
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