Preparation and characterization of ultra-thin ferroelectric PZT films grown by plasma-assisted CVD

The preparation and characterization of ultra-thin ferroelectric PZT films were done using the RF plasma-assisted chemical vapor deposition (CVD) system. The ZrO₂ phase was observed at an early stage of the growth of PZT film (film thickness <430nm). The PZT film, including ZrO₂ phase, was observed to have poor ferroelectric properties. It was found that the ZrO₂ phase could be suppressed by delaying the supply of the Zr source. Even when the thickness was only 46 nm, monolayer PZT films with good ferroelectric properties were successfully grown. The reason for this result is thought to be because the optimum interface was prepared between the substrate and the film before the growth of the monolayer PZT by delaying the supply of Zr and thus suppressing the formation of ZrO₂.