Appeal No. 2005-0123
Application No. 10/114,759
in a semiconductor integrated circuit and depositing metal lines
interconnecting the contacts. Xu summarizes the method (column
8, lines 3-28) as depositing by high density plasma vapor
deposition a first sublayer of refractory metal (such as Ti), a
second sublayer of a refractory metal nitride (such as TiN), and
a third sublayer of the refractory metal (graded from TiN in its
lower portion), and then depositing by a standard plasma vapor
deposition an interconnect metal (such as aluminum). To remedy
the deficiency of Xu, the examiner turns to Simpson.
Specifically, the examiner states (Answer, page 5) that based on
Simpson's disclosure of a method of electroplating copper over a
refractory metal seed layer without an intervening deposition, it
would have been obvious to "replac[e] the sputtered aluminum
layer with electroplated copper since copper is an alternative to
aluminum metalization and electroplating is one of the most
desirable ways to deposit copper."
Appellant agrees (Brief, page 6) that "Simpson's statements
show a general desire in the art to replace aluminum with copper
and the indication of copper electroplating." However, appellant
contends that "Simpson's statements do not provide sufficient
teaching, suggestion or motivation to modify Xu in particular and
therefore the two references cannot be properly combined." In
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