Characterization of Polycrystalline SrRuO3 Thin Films Deposited by DC Magnetron Sputtering Method

Polycrystalline SrRuO3 (SRO) thin films were deposited on SiO2/Si substrate by using the DC magnetron sputtering method for application as buffer electrodes in PZT ferroelectric capacitors. The process parameters, such as the substrate temperature, the pre-heating time, the DC power and the oxygen gas ratio, were systematically varied to obtain high-quality SRO thin films. Among the various process conditions, the substrate temperature was a major factor having a significant effect on the electrical resistivity and the microstructure. Regardless of the deposition conditions, the SRO films showed a columnar structure and a highly (121) orientation at substrate temperatures higher than 450 C. The lowest resistivity obtained was about 440 μ ·cm for the 30-nm-thick SRO film deposited at 550 C. The PZT capacitor with the SRO buffer layer showed a very high remanent polarization value (2Pr 60 μC/cm2) and a small fatigue loss (10 %) after 1 × 1011 switching cycles.% KCI Citation Count: 5