High-Density and Low-Leakage-Current MIM Capacitor Using Stacked $\hbox{TiO}_{2}/\hbox{ZrO}_{2}$ Insulators

We have fabricated high-kappa Ni/TiO
₂
/ZrO
₂
/TiN metal-insulator-metal (MIM) capacitors. A low leakage current of 8 times 10
^-8
A/cm
²
at 125degC was obtained with a high 38- fF/mum
²
capacitance density and better than the ZrO
₂
MIM capacitors. The excellent device performance is due to the lower electric field in 9.5-nm-thick TiO
₂
/ZrO
₂
devices to decrease the leakage current and to a higher kappa value of 58 for TiO
₂
as compared with that of ZrO
₂
to preserve the high capacitance density.