Properties of FRAM capacitors with oxide electrodes

La,SrCoO3 (LSCO) and LaNiO3 (LNO) thin films were deposited on (111) oriented (Pb,La)(Zr,Ti)O-3 (PLZT)/Pt films to form a top electrode and the thin film ferroelectric capacitor properties were evaluated as well as by SIMS to check for interdiffusion. The electrical results indicate that the LSCO capacitor had lower voltage switching, better fatigue endurance and higher remanent polarization than LNO capacitors prepared with PLZT films containing 7% excess Pb. In the case of LSCO, SIMS profiles indicated that the Sr was diffusing into the PLZT film during post-deposition crystallization annealing and leakage increased with increasing excess Ph in the PLZT film. The LSCO results concur with previous results on the interaction of SrRuO3 top electrode and PLZT indicating that Sr based top electrodes are reacting with excess Ph in the PLZT film and this interaction improves the capacitor ferroelectric properties.