Heterogeneous Kinetics between Atomic Oxygen and Metalorganic Precursors 

Gas-phase chemistry can dramatically complicate chemical vapor deposition (CVD) process, and it is usually detrimental to the quality of the resulting films. We have developed two novel approaches for metal oxide CVD which minimize gas-phase chemistry. One is high vacuum plasma-assisted chemical vapor deposition (HVP-CVD), in which the inductively-coupled plasma source shown at right supplies atomic oxygen while the precursor is introduced into the chamber background. The high vacuum environment precludes gas-phase collisions, eliminating chemistry.  A second approach has been to engineer pulsed-plasma-enhanced chemical vapor deposition (P-PECVD) to display atomic layer deposition (ALD), i.e. monolayer/cycle growth behavior. By pulsing the plasma under appropriate conditions one can alternate between precursor exposure and atomic O exposure. The goals of this project are twofold. First, we want to develop an improved  understanding of the deposition chemistry through a combination of extensive diagnostics and detailed modeling, which is being lead by PhD candidate Pieter Rowlette. Second, we are applying these approaches for the development of metal oxides for diverse applications including high k dielectrics, electrochromics, transparent conducting oxides, barrier coatings, and photcatalysts.  MS candidate Scott Szymanski is working on alumina deposition while PhD candidate Mike Seman works with materials for electrochromic windows.  Undergraduate David Richards assists with this work as well.