This award is made by the Office of Special Projects in the Chemistry Division. The research will explore the range of ligand intermediates that may be formed in Chemical Vapor Deposition (CVD) of thin films of important binary and ternary metal nitrides with the formula MN, where M is an early transition metal. CVD routes will be developed using volatile metal halides and nitrogen compounds. A major goal of the work is to identify structures that serve as single-source precursors and to try to understand the chemistry involved in their transformations to binary materials. All new compounds will be characterized by various analytical and spectroscopic techniques. Among the systems to be studied are precursors with hydrazido ligands, monomeric titanium nitrido complexes, amorphous titanium-silicon-nitrogen and tantalum-silicon-nitrogen films as barriers in microelectronics devices, and CVD routes to ternary metal nitrides, which possess properties superior to those of the binary materials. %%% Thin ceramic films made by CVD processes are of growing technological importance. Films of early transition metal nitrides of the type studied in this project possess a number of useful properties, including extreme hardness, excellent chemical resistance, desirable optical characteristics, and good electrical conductivity. The research supported in this project will lead to new precursors and processes for CVD which will solve problems with current methods, such as high deposition temperatures, and will develop paths to new ternary metal nitrides for which no CVD routes are currently available.
