J. Si et al., METAL-ORGANIC CHEMICAL-VAPOR-DEPOSITION OF ZRO2 FILMS USING ZR(THD)4 AS PRECURSORS, Journal of materials research, 9(7), 1994, pp. 1721-1727
Synthesis of zirconium tetramethylheptanedione [Zr(thd)4] was optimize
d. Purity of Zr(thd)4 was confirmed by melting point determination, ca
rbon, and hydrogen elemental analysis and proton nuclear magnetic reso
nance spectrometer (NMR). By using Zr(thd)4, excellent quality ZrO2 th
in films were successfully deposited on single-crystal silicon wafers
by metal-organic chemical vapor deposition (MOCVD) at reduced pressure
s. For substrate temperatures below 530-degrees-C, the film deposition
rates were very small (less-than-or-equal-to 1 nm/min). The film depo
sition rates were significantly affected by (i) source temperature, (i
i) substrate temperature, and (iii) total pressure. As-deposited films
are carbon free. Furthermore, only the tetragonal ZrO2 phase was iden
tified in as-deposited films. The tetragonal phase transformed progres
sively into the monoclinic phase as the films were subjected to a high
-temperature post-deposition annealing. The optical properties of the
ZrO2 thin films as a function of wavelength, in the range of 200 nm to
2000 nm, were also reported. In addition, a simplified theoretical mo
del which considers only a surface reaction was used to analyze the de
position of ZrO2 films. The model predicated the deposition rates well
for various conditions in the hot wall reactor.