Abstract
Pb(Zr 0.3 Ti 0.7 )O 3 (PZT) thin film capacitors fabricated on an oxygen-implanted Pt bottom electrode were studied. Oxygen was implanted at a low acceleration voltage (40 kV) and dose (1×10 15 cm -2 ). Structural examination by grazing-incident X-ray diffraction (GIXD) and chemical analysis by X-ray photoelectron spectroscopy (XPS) revealed that the implantation generated a very thin amorphous top surface layer (approx. 20 nm), which contained approximately 7% of oxygen that stayed in the film in the form of PtO bonding. The amorphous layer, however, resumed the crystalline structure accompanied by the dissociation of PtO under the rapid thermal annealing at 600 °C for 5 min. The remnant polarization of sol-gel derived Pb(Zr 0.3 Ti 0.7 )O 3 (PZT) films fabricated on the oxygen-implanted Pt was slightly reduced from 11.92 μC/cm 2 for the PZT capacitors fabricated on a Pt electrode without implanted oxygen to 9.07 μC/cm 2 . Nevertheless, the fatigue endurance was significantly increased. The switching polarization of PtO x /PZT/Pt (O-implanted) capacitors remained within 95% of the starting value after 4×10 10 switching cycles, which is comparable to that of PZT capacitors made with other conducting oxides. © 2004 Elsevier B.V. All rights reserved.