A study of the pseudo-binary systems M-Si-O (M = Zr, Hf, Ti, Al, Y, La, Ta)
using cluster approach
Vladimir K. Golubev (
)
Molecular Dynamics Group, Sarov Open Computer Center, 53 Zernov
St., Sarov, 607190 Russia.
As is known, the pseudo-binary materials systems are very perspective as
potential alternative gate dielectric candidates. They offer great
opportunities for future CMOS technologies and demand a lot of various
investigations of their properties. In this work the cluster approach is used
for studying the simple model pseudo-binary cluster systems M-Si-O where M =
Zr, Hf, Ti, Al, It, La, Ta.
A large group of Si-Zr clusters, from single as Si(OH)4 and Zr(OH)4 to quinary
as Si5O4(OH)12, Si4ZrO4(OH)12, SiZr4O4(OH)12 and Zr5O4(OH)12, was studied in
the work. For other then Zr elements, the single and binary clusters as
SiHfO(OH)6 and Hf2O(OH)6 were only studied. The HF theory and DFT (B3LYP)
approximation introduced into the Gaussian code were utilized. Several various
basis sets were used in the calculations. The structural and energetic
properties of clusters and effective charges on the atoms were obtained and
analyzed. The structure characteristics were then used for fitting parameters
of the Morse and Buckingham variable-charge interatomic potentials. The method
of fitting with the charge equilibration approach introduced into the GULP
code was utilized. Examination of obtained interatomic potentials was
performed on the other then used for fitting cluster systems.
