We have characterized physical and electrical properties of W-TiN stacked gate electrode structure with TiN as a diffusion barrier of fluorine. As the $N_2/Ar$ gas ratio increased during sputter deposition, TiN thin films became N-rich, and the resistivity of the films increased. However, the resistivity of W-TiN stacked gate reduced as a result of the crystallization of tungsten with the increase of $N_2/Ar$ gas ratio. On the other hand, tungsten in W-TiN stacked gate structure have the (100)-oriented crystalline structure although TiN films were subjected to annealing at high temperature (600~$800^{circ}C$). Leakage currents of W-TiN gate MOS capacitors were less than $10^{-7} extrm{/Acm}^2$ and also were lowered by the order of 2 compared with those of pure W gate electrode.