Appeal No. 1999-2347
Application 08/892,560
Appellants make one argument on the merits. It is argued
that Balda does not teach the limitations of claim 29 (Br29), but
no explanation is provided.
The limitations of claim 29 are taught by or would have been
obvious over Figs. 5 and 6 of Balda. Figure 5 shows depositing a
silicon nitride protection layer 50 over a metal layer 48.
Figure 6 shows etching the silicon nitride layer 50 and metal
layer 48 to form a silicon nitride cap on the metal pad. This
structure is covered by an insulating layer (Fig. 7) and
subjected to a two-step etching process (Figs. 8 & 9). While the
metal layer 48 is not directly on the substrate, the limitation
of claim 21 of "a substrate having a metal pad" does not require
the pad to be directly on the substrate. In any case, however,
Balda teaches forming the etch stop layer as a conformal layer
(Figs. 2-4) or as a cap (Figs. 5-9) and it would have been
obvious to use either method on a metal pad in contact with the
substrate. Thus, we conclude that claim 29 would have been
obvious over Barber, Erie, Kim, and Balda. The rejection of
claim 29 is sustained.
- 27 -
Page: Previous 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 Next
Last modified: November 3, 2007