Appeal No. 2002-2225
Application 09/295,132
using a nitrogen-based plasma after tungsten is deposited as the electrical contact. It is clear
from the process steps disclosed in Vuillermoz that the deposited tungsten sheds the nitrogen
from the plasma in a subsequent annealing step.
On this record, we agree with appellants’ argument that if a doped polysilicon was used
as the electrical contact in place of tungsten in the process of the reference, the polysilicon would
be converted at least in part, if not entirely, to silicone nitride in the presence of the nitrogen-
based plasma. Thus, we find that the silicon nitride layer formed would be thicker than the
electrically conductive diffusion barrier taught in Vuillermoz, which, on this record, would
destroy the intended conductivity of this layer (see specification, page 4, line 21, to page 5, line
1). Therefore, we further agree with appellants that the use of a doped polysilicon as the
electrical contact in the process set forth in Vuillermoz would not have enabled one of ordinary
skill in this art to arrive at the structure having a quantum conductive barrier layer required by
appealed claim 1. See generally, In re Payne, 606 F.2d 303, 314, 203 USPQ 245, 255 (CCPA
1979) (a reference relied upon under § 103 must provide an enabling disclosure, placing the
claimed invention in the possession of the public). Indeed, one of ordinary skill in this art would
have recognized that the structure obtained from the use of a doped polysilicon as an electrical
contact would be inoperative for the purposes of Vuillermoz. See In re Fritch, 972 F.2d 1260,
1265-66, 23 USPQ2d 1780, 1783-84 (Fed. Cir. 1992); In re Gordon, 733 F.2d 900, 902, 221
USPQ 1125, 1127 (Fed. Cir. 1984).
We are not convinced otherwise by the examiner’s arguments. First, it is prior art and not
the disclosure in appellants’ specification, which must show that the interchange of tungsten and
a doped polysilicon as electrical contacts in the context of the claimed structure on a
semiconductor substrate is “non-critical” (answer, pages 5-6). Cf. In re Saunders, 444 F.2d 599,
606-07, 170 USPQ 213, 219-20 (CCPA 1971). Indeed, the claim language of the appealed
claims must be considered vis-à-vis the prior art, regardless of the examiner’s view thereof based
on the disclosure in the specification (answer, pages 5-6). Cf. Ex parte Grasselli, 231 USPQ 393
(Bd. App. 1983), aff’d mem., 738 F.2d 453 (Fed. Cir 1984). And, second, we know of no
authority which supports the examiner’s position that the process of making a product shown by
a reference can be disregarded even though there is no other process shown in the applied
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