Appeal No. 2003-2130
Application 08/159,461
annealing the layers to form a nitride layer only between the oxide layer and the
polysilicon layer . . . .
The examiner does not set forth the factual foundation for a prima facie case under this
section of the statute in the statement of the rejection (answer, page 4). However, it seems that
the examiner’s position is that the italicized phrase limiting the implanted nitrogen ions only to
the polysilicon layer constitutes a “negative limitation or exclusionary proviso” which is not
supported by a showing of fact in the specification and figures thereof in the same manner as the
specification and FIG. 2d of Haddad which “shows nearly the identical structure” to that in
present specification FIG. 10, that is, each of the figures depict implantation of nitrogen ions into
a structure wherein a polysilicon layer is on top of a silicon oxide layer (answer, pages 6-7).
Upon comparison of the respective disclosures, we find that the present specification
discloses in the written description that nitrogen ions are implanted into the polysilicon layer 22,
and upon annealing, silicon nitride layer 20 is formed in the polysilicon layer 22 at the boundary
or interface thereof with the silicon oxide layer 16, as shown in specification FIG. 4, with no
mention anywhere in the specification of any nitrogen implantation in silicon oxide layer 16
and/or subsequent formation of a silicon nitride layer in silicon oxide layer 16 during the
annealing step (e.g., page 9, line 4, to page 10, line 3, particularly, page 9, lines 20-28). In
contrast, we find that Haddad discloses that “as shown in FIG. 2d, a nitrogen ion implantation is
performed . . . [wherein] an implant energy . . . [implanted] nitrogen ions into the polysilicon
[layer] 14 and the [silicon] oxide [layer] 12” (col. 4, lines 7-12; italicized emphasis supplied).
Haddad further discloses in this respect that
FIG. 4 . . . [shows that] the nitrogen profile changes significantly such that there is a
pile-up of nitrogen at the polysilicon/silicon dioxide interface and again at the silicon
dioxide/substrate interface. In other words, within the silicon dioxide layer 12 there are
formed SixNy compounds at the interfaces of the silicon dioxide layer with adjacent
layers (see FIG. 4, peak points 18 and 20). [Col. 4, lines 32-41.]
Thus, according to the examiner, in the absence of express process conditions in the
present specification which confine nitrogen ion implantation and the formation of a silicon
nitride layer by subsequent annealing to the polysilicon layer boundary or interface with the
silicon oxide layer and evidence that this in fact occurs in similar manner to the evidence in
Haddad, there is no disclosure of such a result in the specification, and because the implantation
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