Chemical vapor deposition of tantalum pentoxide films for metal-insulator-semiconductor devices

Thin amorphous Ta2O5 films were deposited by oxygen-assisted pyrolysis of tantalum dichloro-diethoxy-acetylacetonate. Index of refraction and the optical gap measurements of the films were in agreement with previous results. The d-c conduction mechanism appears to be bulk limited following the Poole-Frenkel mechanism with transition towards a space charge limited current at high current densities. The conduction level is high and breakdown voltage is low with respect to SiO2 or Si3N4. The higher dielectric constant of Ta2O5 films could make them attractive in double layer insulator MIS devices