CVD OF HIGH-K DIELECTRIC THIN FILMS,

J.W. Rogers, Jr.

Department of Chemical Engineering, University of Washington, Seattle, Washington, U.S.A.,

In less than 5 years, the Roadmap for semiconductors suggests that silicon dioxide will no longer be an acceptable material for the gate dielectric in MOSFET-based devices. As feature size shrinks, the films of silicon dioxide for gate dielectrics will be so thin (equivalent oxide thickness 1.5-2.0 nm) that growth becomes an issue and electron tunneling through the dielectric layer will prevent their use. The search for new "high k" dielectric materials suitable for these applications is underway. Candidate materials include aluminum nitride, tantalum oxide, titanium oxide, and perhaps perovskites such as the alkaline earth titanates. Chemical vapor deposition will likely be the preferred technique for depositing these films. In this talk I will review our work in the area of aluminum nitride deposition using amine alanes and ammonia as precursors. High quality amorphous thin films have been grown on silicon(100) substrates at temperatures as low as 675 K. Recent results on the deposition of titanium and tantalum oxides using metal alkoxide precursors will also be presented.