Study on oxidization of Ru and its application as electrode of PZT capacitor for FeRAM

Oxidization for Ru through anneal with plenteous oxygen atmosphere and its application as the top electrode of sol–gel PZT capacitor are investigated in this study. PZT capacitor with RuO2 or oxygen-doped Ru as top electrode can be obtained from Ru/PZT/Pt capacitor through slow-rate anneal at 650 °C for 20 min in cannulation furnace. It has larger remanent polarization, better rectangle shape, better fatigue properties and lower leakage current than the other capacitors with PZT film prepared by the same process and different top electrodes in this study. Plenteous oxygen atmosphere and 650 °C in cannulation furnace are important conditions for the oxidation of Ru and renewed crystallization of PZT in this capacitor. Plenteous oxygen at interface can compensate the oxygen vacancies at PZT/electrode interface, which results in the above good characteristics.