Appeal No. 1998-0129 Page 8
Application No. 08/438,062
gallium arsenide substrate in the formulation of a capacitor
having a PZT dielectric layer between the electrodes.
Appellants assert (brief, page 9) that Miller cannot be
combined with McMillan or Koyama because there is no
suggestion or motivation in the prior art to combine the
references. We
find that McMillan (page 2) discloses that “[a]s indicated in
Figure 1, it appears, however, that barium strontium titanate
[BST] . . . could overcome many of these problems and easily
satisfy the requirements for the next generation of ULSI
DRAM’S. Rather high dielectric constant values have been
reported . . . ” and that (page 8) “[w]e have shown that very
good . . . barium strontium titanate [BST] can be deposited
via LSCVD. We have now achieved sufficient success with this
method of deposition . . . .” From these teachings of
McMillan, we are in agreement with the examiner (answer, page
6) that McMillan suggests that one of ordinary skill in the
art would have been taught to replace the high dielectric PZT
in the capacitor of Miller with BST in order to overcome many
of the problems associated with the use of PZT.
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Next
Last modified: November 3, 2007