Abstract
The hydrogen barrier effect of SrRuO3(SRO) top electrode in SrBi2Ta2O9(SBT) ferroelectric capacitors was investigated. Both the SRO(270nm) and SBT(250nm) thin films were prepared by pulsed laser deposition. The remnant polarization of SRO/SBT/Pt capacitor was kept to be 8 μ C/cm2 after 3%H2/He treatment even at 400°C for 10min. Moreover, after annealing at 200°C for 10min in 3%H2, the remnant polarization during 1010 switching cycles was nearly constant. These results indicate that the SRO top electrode works as a hydrogen barrier. In case of Pt/SBT/Pt capacitor, x-ray diffraction peaks of SBT thin films disappeared after the H2 treatment even at 200°C for 20 hours. On the other hard, deffraction peak intensities of both SRO and SBT thin films in SRO/SBT/Pt capacitor remained the same after H2 treatment. The SRO top electrode is very attractive for highly integrated ferroelectrice nonvolatile memory applications.
