Improvement of Endurance in HZO-Based Ferroelectric Capacitor Using Ru Electrode

Abstract

In this letter, the endurance property of Hf0.5Zr0.5O2(HZO) based ferroelectric capacitor has been improved using Ru electrodes. Compared to the widely used TiN/HZO/TiN capacitor, the Ru/HZO/Ru capacitor shows comparable remnant polarization ( ${\sim }20~\mu C/cm^{2}$ ), lower leakage current ( $5.67\times 10^{-5}A/cm^{2}$ ) and higher breakdown electric field (~4 MV/cm) at room temperature. The reduction of the leakage current and the enhancement of the breakdown electric field, which are ascribed to the small number of defects and vacancies in HZO thin films with Ru electrodes, prompt the endurance improvement of HZO-based capacitor from $3\times 10^{10}$ cycles for TiN electrodes at 3 MV/cm to more than $1.2 \times 10^{11}$ cycles for Ru electrodes at 3.5 MV/cm. This work provides an effective way to reduce the leakage current and improve the endurance property of HZO-based capacitors.