Switching properties of SrRuO ₃ /Pb(Zr _0.4 Ti _0.6 )O ₃ /SrRuO ₃ capacitor grown on Cu-coated Si substrate measured at various temperatures

Abstract

SrRuO3(SRO)/Ni-Al/Cu/Ni-Al/SiO2/Si heterostructures annealed at various temperatures are found to remain intact after annealing. Moreover, a SRO/Pb(Zr0.4Ti0.6)O3 (PZT)/SRO capacitor is grown on a Ni-Al/Cu/Ni-Al/SiO2/Si heterostructure, which is tested up to to investigate the reliability of the memory capacitor. It is found that besides the good fatigue resistance and retention characteristic, the capacitor, measured at 5 V and room temperature, possesses a large remnant polarization of and a small coercive voltage of 0.83 V, respectively. Its dominant leakage current behavior satisfies the space-charge–limited conduction at various temperatures. Very clear interfaces can be observed from the cross-sectional images of transmission electron microscopy, indicating that the Ni-Al film can be used as a diffusion barrier layer for copper metallization as well as a conducting barrier layer between copper and oxide layer.