The modulation of Schottky barrier height of NiSi/n-Si Schottky diodes by silicide as diffusion source technique

This paper reports that the Schottky barrier height modulation ofNiSi/n-Si is experimentally investigated by adopting a novelsilicide-as-diffusion-source technique, which avoids the damage tothe NiSi/Si interface induced from the conventional dopantsegregation method. In addition, the impact of post-BF₂ implantationafter silicidation on the surface morphology of Ni silicides is alsoillustrated. The thermal stability of Ni silicides can be improvedby silicide-as-diffusion-source technique. Besides, the electronSchottky barrier height is successfully modulated by 0.11~eV at aboron dose of 10¹⁵~cm^-2 in comparison with thenon-implanted samples. The change of barrier height is notattributed to the phase change of silicide films but due to theboron pile-up at the interface of NiSi and Si substrate which causesthe upward bending of conducting band. The results demonstrate thefeasibility of novel silicide-as-diffusion-source technique for thefabrication of Schottky source/drain Si MOS devices.