Improved Stress Reliability of Analog Metal-Insulator-Metal Capacitors Using TiO2/ZrO2 Dielectrics

Abstract

We have studied the stress reliability of high-k Ni/TiO2/ZrO2/TiN metal-insulator-metal capacitors under constant-voltage stress. The increasing TiO2 thickness on ZrO2 improves the 125-degrees C leakage current, capacitance variation (Delta C/C), and long-term reliability. For a high density of 26 fF/mu m(2), good extrapolated ten-year reliability of small Delta C/C similar to 0.71% is obtained for the Ni/10-nm-TiO2/6-5-nm-ZrO2/TiN device at 2.5-V operation.