Appeal No. 1998-0129 Page 19
Application No. 08/438,062
have suggested to one of ordinary skill in the art. As
acknowledged by appellants (brief, page 7) “McMillan et al.
shows Ba Sr TiO .” We find that McMillan specifically
0.70.3 3
teaches the use of Ba Sr TiO as a high dielectric material
0.7 0.3 3
in a capacitor and teaches the use of BST to overcome many of
the problems associated with the use of high dielectric
constant PZT. From the teachings of Miller and McMillan of
providing a capacitor having Ba Sr TiO on a gallium arsenide
0.7 0.3 3
layer and a diffusion barrier layer, we find that one of
ordinary skill in the art would have been motivated to have
utilized Ba Sr TiO in a high dielectric capacitor to
0.70.3 3
overcome problems associated with PZT, as recognized by
McMillan. We find that in view of McMillan’s specific
disclosure (Figure 2) of both ferroelectric BST and non-
ferroelectric BST, i.e., Ba Sr TiO , as a dielectric
0.7 0.3 3
material, that the resultant structure from the combined
teachings of the prior art references of Miller and McMillan
would have been a capacitor as taught by McMillan on a gallium
arsenide substrate including a diffusion barrier layer, and a
BST layer that would have been either ferroelectric or non-
ferroelectric (Ba Sr TiO ). We therefore, conclude that the
0.7 0.3 3
Page: Previous 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Next
Last modified: November 3, 2007