GAS AND ADSORBATE EXCITATION PATHWAYS IN SYNCHROTRON-RADIATION EXCITED SI GROWTH USING DISILANE

We studied reaction kinetics in synchrotron radiation excited chemical vapor deposition of Si using disilane. It was found that the growth rate depends on temperature in the irradiated region but not in the nonirradiated region. Growth in the irradiated region occurs as a result of photolysis of disilane molecules weakly trapped on the surface followed by the formation of a hydrogenated Si network. On the other hand, in the nonirradiated region, growth occurs as a result of layer-by-layer sticking and the elimination of surface hydrogen by a fragment species generated by photolysis of gas-phase disilane. The reaction model is consistent with properties of the grown Si film.