Appeal No. 2004-0652
Application No. 09/396,642
DISCUSSION
I. The 35 U.S.C. § 102(b) rejection of claims 1, 2, 4, 5 and 7 as
being anticipated by Nishioka
Nishioka pertains to methods for forming capacitors
containing materials having high dielectric constants. In
general, the capacitors comprise a silicon semiconductor
substrate 30, an insulative SiO2 layer 32 overlying the
substrate, a TiSi2/poly-Si plug 34 providing electrical
connection through the SiO2 layer, a lower electrode consisting
of a conductive adhesion layer 36 or 46 of either TiN (Figures 1
through 4) or Ru (Figures 5 through 8) deposited on the SiO2
layer and a Pt layer 38 overlying the adhesion layer, a high
dielectric constant BST layer 42 deposited over the lower
electrode, and an upper electrode consisting of a Pt layer 44
overlying the BST layer. In order to minimize expansion and
cracking of the BST layer 42 during its formation, Nishioka
deposits the respective adhesion layers in a substantially
unoxidized state and then pre-oxidizes their sidewalls to reduce
any further oxidation and expansion during the BST layer
deposition (see column 4, lines 39 through 63). The pre-
oxidation step forms a non-conductive TiO2 sidewall 40 on the TiN
adhesion layer 36 and a conductive RuO2 sidewall 50 on the Ru
adhesion layer 46. With regard the pre-oxidation of the TiN
4
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