CVD of Tungsten Metal Oxides, Sulfides and Nitrides for Device Applications

Gas sensors require high surface area materials to facilitate interaction with the analyte and electron migration through the device. Nanowires of tungsten oxide (WO_x) are promising candidates for this application. We are synthesizing volatile tungsten precursors with oxo and alkoxide ligands as single source precursors for the Chemical Vapor Deposition (CVD) of WO_x. Variation of the ligands allows control of the volatility, decomposition chemistry and materials properties of the deposited films.  High temperature growth of WO_x by Aerosol Assisted CVD, results in nanowires that are currently being studied in sensors in a collaborative project.

Two dimensional transition metal chalcogenide (TMD) materials such as MoS₂ and WS₂ have potential applications in nanoelectronics, sensors, batteries and catalysis. We are synthesizing precursors for the CVD of MoS₂ and WS₂ films and nanostructures. Using mechanism-based precursor design, we are studying the ways in which the precursor chemistry and interactions with the substrate influence the growth habit of the resulting TMD. 

Transition metal nitrides have been of interest as diffusion barriers to confine the metal in integrated circuits.  We are synthesizing nitirido, imido and hydrazido complexes as precursors for the CVD of metal nitride thin films.