A New Cost-Effective Metal–Insulator–Metal Capacitor Processed at 350 $^{\circ}\hbox{C}$ Using $ \hbox{Ni}_{2}\hbox{Si}$ Fully Silicided Amorphous Silicon Electrodes

Without requiring noble metal materials, a novel low-cost Ni 2 Si/TiO 2 /Ni 2 Si metal-insulator-metal (MIM) capac itor processed at 350°C has been developed using nickel fully sili cided (Ni-FUSI) amorphous silicon electrodes. A high capacitance density of 17 fF/μm 2 along with a low top-electrode resistivity of ~38 μΩ · cm were achieved. At 25°C, this MIM capacitor also displays a good leakage current density of 6.4 × 10 -6 A/cm 2 at -1 MV/cm (-2.5 V) and a quadratic voltage coefficient a of 4110 ppm/V 2 . Schottky emission dominates the leakage current in low negative field ( ;1.4 MV/cm). The Schottky barrier height Φ B at the Ni 2 Si/TiO 2 interface was first extracted to be 0.8 eV, whereas the trap barrier height Φt in the TiO 2 film was 0.39 eV. Material characterization further reveals that this structure is highly appropriate for future ultralarge-scale-integration technologies.