Atomic and electronic structure of ZrO2 film on Si(100) grown by low temperature chemical vapor deposition

The low-temperature chemical vapor deposition (CVD) of ZrO2 films has attracted attention due to its potential for integration with a wide range of substrates and applications. In addition, understanding the atomic structure and electronic properties of CVD-grown ZrO2 films is essential for predicting their physical and chemical behavior. In this study, we developed a custom-designed CVD apparatus and successfully synthesized a ZrO2 film on a Si substrate at a substrate temperature of 150 °C using tetrakis(ethylmethylamino)zirconium as the precursor. A film thickness of ∼1–2 nm was achieved after a 30 min deposition process. Zr K-edge extended x-ray absorption fine structure analysis revealed that the film exhibits a polycrystalline structure with a Zr–O bond length of 2.16 Å. The electronic structure of the film was investigated using Zr L3-edge x-ray absorption near-edge structure, electron energy loss spectroscopy, and ultraviolet photoelectron spectroscopy. These measurements showed that the electronic properties of the CVD-grown ZrO2 film, particularly the valence band structure, are broadly comparable with those of bulk ZrO2. The results suggest that the ZrO2 film synthesized by low-temperature CVD can be suitable for use in electronic and optical devices, especially where thermal constraints are a concern.