FORMATION OF HIGH-CONDUCTIVITY WSIX LAYER AND ITS CHARACTERIZATION ASA GATE ELECTRODE

A novel integrated clustered electrode for gate electrode application has been developed. This method includes a sequential deposition of in situ phosphorus doped polycrystalline silicon and dichlorosilane-base d tungsten silicide films using a clustered platform without a vacuum break. The dopant atom: phosphorus, in the polycrystalline silicon sub strate enhances the reduction of WF6, resulting in the formation of an amorphous layer (WS1.1) with a uniform thickness and a lower resistiv ity of 234 mu Omega cm. Upon thermal annealing, the composition of the silicide was converted into WSi2.2 with an accompanying thickness inc rease of the silicide. At the interface of WSix/polycrystalline silico n, no defects due to the thickness change were observed at all, while the grain size and the resistivity of the silicide were measured to be 100-400 nm and about 36 mu Omega cm, respectively As a result of its application to a complementary metal oxide semiconductor device having a 0.25 mu m minimum linewidth, the line resistance was three times lo wer than with the conventional WSix. In addition, characteristics such as the dopant depletion of the gate electrode and the reliability of the gate oxide were superior to those of the conventional WSix. This s ystematic study has also reviewed the correlation between the silicide 's structural properties and device performance.