Low Contact Resistivity Of Ti/Tin/Al For Nisi2 On Epitaxial Si:P Structure At Full Low-Temperature Process Below 450 Degrees C

Combined with Ti/TiN/Al for ultra-thin NiSi2 and in situ-doped Si:P, an ultra-low contact resistivity of 4.6 x 10(-9) omega cm(2) was achieved under a low thermal budget (<= 450 degrees C). The in situ-doped Si:P layer was grown by molecular beam epitaxy at 350 degrees C with a high doping concentration of 1.2 x 10(21) cm(-3) exceeding the solid solubility. On the Si:P substrate, ultra-thin NiSi2 film of 12.8 nm was formed by low-temperature drive-in diffusion and alloying at 180 degrees C and 450 degrees C, respectively. The Ti/TiN/Al-NiSi2-Si:P scheme provides a solution to the dilemma between performance boosting and reliability degradation in advanced very-large-scale integration manufacturing technology. It can also be applied in future monolithic three-dimensional integration.