TITANIUM SILICIDE FORMATION IN TISI2 TIB2 BILAYER BARRIER STRUCTURE/

Titanium disilicide is used as a sublayer in the TiB2/TiSi2 barrier st ructure to prevent fast outdiffusion of boron from titanium boride int o the semiconductor device. The TiB2/TiSi2 bilayer was deposited by ma gnetron sputtering, and the low resistance C54 TiSi2 layer was formed by post-deposition vacuum annealing. Go-sputtering method was used to deposit the TiSi, sublayer. The composition of the as-deposited films was monitored by Auger spectroscopy, and formation was studied by X-ra y diffraction (XRD) and cross-sectional TEM (XTEM). It was found by XR D and high-resolution TEM that the as-deposited bilayer had an amorpho us structure. Titanium silicide was formed not only in the co-deposite d layer between the Ti and Si atoms, but also at the Si-TiSi2 interfac e.