Electrical properties of PZT thin films grown on Ir/IrO2 bottom electrodes by MOCVD

Electrical properties of Ir/IrO2/PZT/Ir/IrO2 and IrO2/IrPZT/Ir/IrO2 capacitors were investigated. SIMS analysis showed that the Ir/IrO2 bottom electrode acted as a good barrier layer of the interdiffusion. Ir/IrO2/PZT/Ir/IrO2 capacitors did not show good electrical properties due to plasma damage during top electrode sputtering. On the other hand, IrO2/Ir/PZT/Ir/IrO2 capacitors showed no fatigue up to 10(9) cycles, when annealing after top electrode deposition was performed. Electrical properties of IrO2/Ir/PZT/Ir/IrO2 capacitors were dependent on the thickness of Ir/IrO2 bottom electrode. These experimental results suggested that electrical properties of PZT capacitors were influenced by the interdiffusion at the bottom interface and the plasma damage at the upper interface.