H. Shinriki et al., ETHANOL-ADDITION-ENHANCED, CHEMICAL-VAPOR-DEPOSITED TANTALUM OXIDE-FILMS FROM TA(OC2H5)(5) AND OXYGEN PRECURSORS, Journal of the Electrochemical Society, 145(9), 1998, pp. 3247-3252
Citations number
9
Categorie Soggetti
Electrochemistry,"Materials Science, Coatings & Films
An innovative chemical vapor deposition (CVD) technique of Ta2O5 film
from Ta(OC2H5)(5) including ethanol and oxygen precursors is demonstra
ted in this paper. High deposition rate of approximately 10 nm/min is
obtained by employing Ta(OC2H5)(5) including ethanol and oxygen precur
sors at 350 degrees C. Temperature-programmed decomposition analysis s
hows that decomposition of ethanol, adsorbed on the Ta2O5 film surface
, into hydrogen and aldehyde begins at 250 degrees C. These results su
ggest that Ta2O5 film plays a role as a catalyst for dehydrogenation o
f ethanol. Under oxygen ambient, water seems to be easily generated on
the Ta2O5 surface by reaction between the hydrogen and oxygen. Hydrol
ysis of ethoxide on the surface promotes deposition of Ta2O5 film. Car
bon concentration included in the as-deposited Ta2O5 film can be remar
kably reduced by the plasma oxygen annealing at 350 degrees C. Combina
tion of the CVD at 350 degrees C and plasma-activated oxygen annealing
at 350 degrees C provide favorable insulative properties for future d
ynamic random access memories and make it possible to form the film on
the storage node while preventing oxidation of the storage node.