Abstract
Ta2O5 thin films were deposited at 155–400°C on amorphous SiO2 and Pt/TiOx/SiO2/Si substrates by metal organic chemical vapor deposition (MOCVD) from tri(tert-butoxy)(isopropylimido)tantalum [Ta[NCH(CH3)2][OC(CH3)3]3]–O2, tri(tert-butoxy)(tert-butylimido)tantalum [Ta[NC(CH3)3][OC(CH3)3]3]–O2 and pentaethoxy tantalum [Ta(OC2H5)5]–O2 systems. Temperature dependency of the deposition rate was almost the same for the films from Ta[NCH(CH3)2][OC(CH3)3]3–O2 and Ta[NC(CH3)3][OC(CH3)3]3–O2 systems irrespective of the kinds of substrates, and the deposition rate of these two systems was higher than that of Ta(OC2H5)5–O2 system for all deposition temperature range within the present study. Dielectric properties of Ta2O5 thin films deposited on Pt/TiOx/SiO2/Si substrates at 200°C from Ta[NC(CH3)3][OC(CH3)3]3–O2 system and at 300°C from Ta(OC2H5)5–O2 system were also investigated. In spite of their 100°C lower deposition temperature, the Ta2O5 films from Ta[NC(CH3)3][OC(CH3)3]3–O2 system showed lower leakage current density and almost the same dielectric constant with those from Ta(OC2H5)5–O2 system.
