Appeal No. 96-4052
Application 08/198,511
semiconductor compounds, discloses that the electrical contact
may be the mask (col. 5, lines 59-60) or "ohmic contacts
formed by the electrodeposition of gold" (col. 6,
lines 17-18). Since the contact is required only for etching,
one of ordinary skill in the art would have known to remove it
after etching. For these reasons, we sustain the rejection of
claims 35 and 39.
Claim 36 requires a contact made of layers of titanium
(Ti), titanium nitride (TiN), and platinum (Pt). Claim 38
recites an additional layer of gold (Au). The examiner states
that "it is also admitted (and obvious to use) that SiC is
frequently contacted with Titanium, and Steitz teaches
covering a titanium contact with layers of TiN, Pt, and Au,
which would [have] be[en] obvious in etching SiC" (FR3; EA3).
The specification states that "Ti or TiC, as an ohmic contact
to n-type $-SiC, has been extensively discussed in the
literature . . ." (specification, page 14, lines 20-22), which
is taken as an admission that the teaching is in the prior
art. Appellants state that only Ti or TiC was admitted,
whereas the claims call for a compound layer of Ti/TiN/Pt
(claim 36) or Ti/TiN/Pt/Au (claim 38) and that Steitz does not
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