NiSi nano-contacts to strained and unstrained silicon nanowires

Nano-contacts of NiSi to n
⁺
and p
⁺
doped strained and unstrained Si nanowires (NWs) were studied. Several Ni silicide phases were found: Ni
₂
Si formed under the Ni electrodes, Ni
₃
Si very close to the Ni electrodes, while NiSi was observed along the Si NWs. The NiSi nanowire length decreases with increasing wire cross section A. The silicidation speed along the Si NW shows a linear relation to 1/A, indicating volume silicidation of the Si NW. Uniaxial strain seems to have no effect on the silicidation speed. Contact resistivities as low as 1.2 × 10
^-8
Ω·cm
²
were obtained for NiSi contacts to both, strained and unstrained Si nanowires.