Conducting oxide electrodes for ferroelectric films

Abstract

Suitability of oxide electronic conductors [e.g. ruthenium oxide (RuO_x) and indium-tin-oxide (ITO)] as contact metallization for ferroelectric films (e.g. PbZr_xTi_1−xO₃) was investigated using techniques such as Rutherford backscattering spectrometry, x-ray diffraction and electron spectroscopy for chemical analysis. Thin films of RuO_x and ITO were deposited on Si substrates by reactive sputtering. Either PbO or PZT (x = 0.53) films were deposited onto the conducting oxides and the specimens were annealed at various temperatures between 400°C and 700°C. Less intermixing was found in Si/RuO_x/ PZT films when compared to Si/ITO/PZT under similar processing conditions. The ferroelectric properties of PZT films on RuO_x electrodes are compared to those on Pt electrodes. The PZT films show improved fatigue properties on RuO_x electrodes.