Titanium disilicide formation by rf plasma enhanced chemical vapor deposition and film properties

Titanium disilicide thin films have been deposited on Si(1 0 0) substrate by rf plasma enhanced chemical vapor deposition using TiCl4/H2 gas mixture at different deposition temperatures. At low temperature of 650 °C excessive silicon substrate etching took place and silicide formation could not be confirmed. While at 700 °C Ti5Si3 was the only detected phase as found by X-ray diffraction (XRD) analysis. As the deposition temperature increased from 750 to 900 °C, the polycrystalline C54-TiSi2 phase deposited. Morphology of the film surface changed noticeably as the deposition temperature increased. At low temperature of 700 °C the film had a flake structure. Increasing the temperature up to 850 °C resulted in a continuous film with smoother grains, while at 900 °C agglomeration of grains took place resulting in coarse grains and discontinuous film. At the optimum experimental conditions it was possible to deposit a homogeneous film with smooth interface and suppressing silicon etching.