Ir Thin Films for PZT Capacitors Prepared by MOCVD Using a New Ir Precursor

Abstract

ABSTRACTPreparation of Ir thin films for PZT capacitors by MOCVD using a new liquid Ir precursor, Ir(EtCp)(CHD) was investigated. Ir thin films with a highly reflecting surface and (111)-orientation were successfully obtained at 230–400 C. When Ir(EtCp)(CHD) was used, shorter incubation time (20min at 230°C and not observed above 240°C) and higher nucleation density (300–400mm-2at 250–300°C) were observed because of its lower decomposition temperature (300°C) than that of previously reported liquid precursor, Ir(EtCp)(COD). Resistivity of 100nm-thick Ir films grown at 250–350°C were less than 20μΩ·cm. PZT capacitors with top and bottom electrodes prepared using Ir(EtCp)(CHD) showed D-E hysteresis loop with Pr of 15μC/cm and Ec of 60kV/cm. No degradation of switching up to 10 switching cycles by bipolar pulses of ±231kV/cm (±3V) and 500kHz.