Infrared Studies of Ozone-Organosilicon Chemistries for SiO2 Deposition

Gas-phase Fourier transform infrared spectroscopy has been used to monitor reactants and products in the study of O3 decomposition and the reaction of O3 with tetramethylsilane and tetraethoxysilane. The results confirm the interpretation that O3 decomposition is heterogeneous, and a dominant factor in SiO2 deposition using these chemistries. Product analysis shows that the higher reactivity of TEOS with O3 is probably due to the ability of TEOS to undergo α-hydride elimination of one ethoxy group, per molecule, and one oxidative acetic acid elimination, per molecule, during the deposition process. Results also suggest elimination via the Sicenter involving a single ethoxy group rather than via a 6-center elimination involving two ethoxy groups.