Fatigue and Retention of Pb(Zr[sub(0.53)]Ti(0.47)])O[sub(3)] Thin Film Capacitors with Pt and RuO2 Electrodes

MgO) two bottom electrodes were used: Pt and Ru02. The RuOz and Pt electrodes were deposited by ion beam sputter deposition using procedures which were pre­ viously developed. 6 In addition, a Ti layer was also deposited by ion beam sputter deposition to improve Pt adhesion. The Ru0 2 bottom electrodes were annealed at 800°C for 10 minutes in air prior to PZT film deposition. PZT thin films (0.180 . 2 0 pm thick) were subsequently deposited by a spin-on sol-gel process similar to that described by Schwartz et al.7 The solution used to make films for this study had a Zr/Ti ratio of 53/47 and a 5% excess lead to compensate for lead loss during annealing. Each film was formed by multilayer deposition, with each layer heated at 300°C for 5 minutes in air. The films were finally annealed at temperatures of 700-750°C for 1 0 minutes in air. Each layer was approximately 900 A thick and the final film thickness was around 1800 A. The top electrodes were sputterdeposited and patterned either by positive photolithography followed by ion beam etching (500 eV Ar + ) or by lift-off photolithography.