Fatigue-free RuO2/Pb(Zr,Ti)O3/RuO2 capacitor prepared by metalorganic chemical vapor deposition at 395°C

We deposited an RuO2/Pb(Zr0.40Ti0.60)O-3/RuO2 capacitor by metalorganic chemical vapor deposition. RuO2 and Pb(Zr0.40Ti0.60)O-3 films were prepared at 350, 395, and 445 degreesC from respective Ru(C7H11)(C7H9)-O-2 and Pb(C11H19O2)(2)-Zr(O.t-C4H9)(4)-Ti(O.i-C3H7)(4)-O-2 systems. Good ferroelectricity was observed for PZT films deposited at 445 degreesC but not at 395 degreesC. However, we obtained ferroelectricity with a remanent polarization above 30 muC/cm(2) by inserting a 10-nm-thick sputtered-Pt layer between the PZT and RuO2 bottom electrodes, which improved the crystallinity of PZT films even those deposited at 395 degreesC. This capacitor had hardly any fatigue after 1x10(10) switching cycles. This demonstrates the possibility of preparing fatigue-free capacitor all deposited below 400 degreesC for high-density ferroelectric random-access memory applications. (C) 2003 American Institute of Physics.