Homogeneous and Heterogeneous Chemistry Models of the Codeposition of Silica, Alumina, and Aluminosilicates Development and Experimental Validation

摘要: The chemical vapor codeposition (CVD) of silica, alumina, and aluminosilicates from mixtures silicon tetrachloride or methyltrichlorosilane (MTS), aluminum trichloride, carbon dioxide, hydrogen is addressed, detailed homogeneous surface reaction mechanisms that describe the chemistry process are formulated. Information obtained thermodynamic analysis equilibrium gas phase past experimental theoretical studies employed to determine which elementary steps play an important role in deposition process. Homogeneous heterogeneous models were formulated by us for silica alumina chlorosilane (silicon MTS) respectively, dioxide used as submodels mechanism. Experimental data a hot-wall, CVD reactor our laboratory validate predictions model. A comprehensive study effect operating conditions (e.g., temperature) residence time on variation gas-phase composition, species coverages, rate conducted range experiments. model found be capable predicting most behavior patterns observed experiments, including those enhancement presence uf AlCl 3 feed, suppression incorporation deposit silane higher MTS.