High-Temperature Leakage Improvement in Metal–Insulator–Metal Capacitors by Work–Function Tuning

Using low-cost and high work-function Ni, a low leakage current of 5times10^-6 A/cm² at 125 degC is obtained in a high 25-fF/mum²-density SrTiO₃ metal-insulator-metal (MIM) capacitor processed at 400 degC. This is approximately two orders of magnitude better than the same device using a TaN electrode, with added advantages of improved voltage and temperature coefficients of capacitance. This work-function tuning method also has merit for achieving both low thermal leakage and high overall kappa value beyond previous laminate structure