High-Performance MIM Capacitors Using Zr-Sn-Ti-O Dielectrics Derived from Atomic Layer Deposition

Metal-insulator-metal (MIM) capacitors fabricated with Zr-Sn-Ti-O dielectrics by the plasma-enhanced atomic layer deposition (PEALD) were first demonstrated. By changing the pulse cycle ratio and cycle number of PEALD, the comprehensive electrical properties of the Zr-Sn-Ti-O MIM capacitors were optimized to meet the requirements of system-level chips for the high-density MIM capacitors. When the cycle ratio of ZrO2:SnO2:TiO2 is 2:10:2, the sample of Zr0.45Sn0.06Ti0.48O2 shows the best electrical properties: a capacitance density of 10.8 fF/mu m(2), a quadratic voltage linearity of -83 ppm/V-2, a leakage current density of 5 x 10(-7) A/cm(2) at 3 V, a breakdown voltage of 6.8 V, and a temperature linearity coefficient of 95.1 ppm/degrees C. These results indicate that PEALD Zr-Sn-Ti-O dielectrics are promising candidates for future high-density MIM capacitor applications in radio frequency and analog-/mixed-signal integrated circuits.