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

Titanium disilicide thin films have been deposited on Si(l 0 0) substrate by rf plasma enhanced chemical vapor deposition using TiCl4/H-2 gas mixture at different deposition temperatures. At low temperature of 650 degreesC excessive silicon substrate etching took place and silicide formation could not be confirmed. While at 700 degreesC Ti5Si3 was the only detected phase as found by X-ray diffraction (XRD) analysis. As the deposition temperature increased from 750 to 900 degreesC, the polycrystalline C54-TiSi2, phase deposited. Morphology of the film surface changed noticeably as the deposition temperature increased. At low temperature of 700 degreesC the film had a flake structure. Increasing the temperature up to 850 degreesC resulted in a continuous film with smoother grains, while at 900 degreesC 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. (C) 2002 Elsevier Science B.V. All rights reserved.