This award is made by the Office of Special Projects in the Chemistry Division under the Materials Synthesis and Processing Initiative. The research will explore the range of ligand intermediates that may be formed in thin film depositions of binary early transition metal oxides, sulfides and nitrides. Chemical Vapor Deposition (CVD) routes to thin films will be developed using volatile metal halides and organic oxygen, nitrogen and sulphur compounds. The coordination chemistry of titanium, zirconium and hafnium tetrachlorides with alcohols, amines and thiols will be investigated to gain a deeper understanding of the types of ligand ensembles that may be produced in film-forming processes. Complexes will be prepared in both solution phase and gas phase reactions in order to understand the relationship between these potentially divergent processes. All stable complexes will be evaluated as CVD precursors. A mechanistic sequence for each material that leads from starting materials to the thin film will be developed. %%% Thin ceramic films made by CVD processes are of growing technological importance. The range of ligand intermediates that can be supported at a metal will illustrate broad principles of CVD that can be applied to other film depositions and greatly enhance chemical predictability.
