Appeal No. 2006-2218
Application No. 10/029,649
Merchant, on the other hand, describes cleaning of the wafer
surface prior to bonding as unnecessary (Merchant, col. 5, ll.
30-35) implying that bonding still takes place even if the
cleaning step is not performed. The bonding alloy that includes
the oxide affinity material can then remove the oxide when the
cleaning step is not performed and native oxide is present. As
argued by the Examiner (Answer 14), the metal layer 62 of
Terasawa is sufficient to remove a native oxide from the bonding
interface between the substrates since the metal layer is made of
Au-Sb alloy which has an affinity for oxygen higher than that of
silicon (Terasawa, col. 5, ll. 12-21).
We also observe that a composition ratio or the amount of
the oxide affinity material in the bond structure for the gold
alloy, as argued by Appellant (Br. 19), is not described in
Appellant’s Specification. Therefore, to the extent disclosed,
any combination ratio of Au-Sb specified by the references is
capable of removing the native oxide on the silicon substrate
interface.
Based on our analysis above, we remain unpersuaded by
Appellant’s arguments that the Examiner erred in determining the
obviousness of the claimed subject matter. Accordingly, as the
Examiner has established a prima facie case of obviousness with
5
Page: Previous 1 2 3 4 5 6 7 8 Next
Last modified: September 9, 2013