| 摘要 |
A titanium layer is formed by depositing titanium over entire surface of a gate electrode, a P-type silicon substrate, an insulation layer, an oxide layer and so forth. By effecting first RTA (Rapid Thermal Annealing) under nitrogen atmosphere, titanium silicide layer of C49 type structure is formed. At this time, the regions of the titanium layer which are on the oxide layer and the insulation layer and upper part of the region of the titanium layer which is formed on the silicon substrate are reacted with N2 gas to produce titanium nitride layer. In conjunction therewith, titanium layer on the surface of the insulation layer and the oxide layer is slightly reacted to form titanium silicide thin film. Subsequently, only titanium nitride is selectively removed. Thereafter, under oxygen atmosphere, second RTA is performed at 850 DEG C. for 10 sec. to oxidize the titanium silicide thin film to make it insulative. At the same time, the titanium silicide layer of C49 type structure is caused phase transition into titanium silicide layer of C54 type structure with lowering of electric resistivity.
|
