Characterization of Reverse Leakage Current of Shallow Silicide Junction

다국어 초록 (Multilingual Abstract)

The properties of PECVD-WN_x films produced in a WF_6-N₂-H₂ gas system and their application as a glue layer for a W metallization were investigated. As the N₂/H₂ ratio in reactant gas increased from 0 to 1.5, the nitrogen concentration and the electrical resistivity in WNX film increased from 0 to 25 at % and 25.5 to 1009 Ω-cm, respectively. In the N₂/H₂ ranges, the microstructure of the film was also shown to be changed as bcc-W, mixture of W+WN+W₂N, amorphous or nanocrystal, and W₂N, in turn. The film of the best qualities was obtained at the N₂/H₂ ratio of 0.25, where it represented the most smooth surface, 230μΩ-cm of resistivity, 13 at.% of nitrogen concentration, nanocrystalline structure close to amorphous at as-deposited state, and 90% of bottom step coverage. In order to proceed further CVD-W metallization, a PECVD-W layer was employed as a seed layer for the stable deposition of the thermal CVD-W onto the WNX layer. A tri-layer structure of (thermal)CVD-W/PECVDW/PECVD-WN_x with a good thermal stability was successfully achieved in an in-situ process, and hence its application to CVD-W metallizations seemed to be promising.