Mocvd of Tantalum Pentoxide for Large-area Ulsi Circuit Wafers

Ta2O5 films of 10-150 nm thickness were prepared by oxygen-assisted pyrolytic LPCVD at 450-490°C from tantalum penta ethoxide and 0 2 with N2 diluent. Silicon wafers 150 mm in diameter were used as substrates with a novel LPCVD reactor. The films were annealed in dry 0 2 a t 700-800°C. Compositional, structural, and electrical evaluations demonstrate that these uniform, pure, and conformal Ta2O5 films are a viable alternative dielectric suitable for advanced megabit DRAM applications.