The effects of O2/Ar ratio on the structure and properties of hafnium dioxide (HfO2) films

HfO2 films at various O2/Ar flow ratios were prepared by reactive dc magnetron sputtering. The effects of O2/Ar ratio on the structure and properties of HfO2 films were studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and UV-Visible spectroscopy. The results showed that the HfO2 films were amorphous at different O2/Ar ratios, and the atomic ratio of O/Hf in the HfO2 films at high O2/Ar ratio was nearly to 2:1. The peaks of Hf4f and O1s shifted to higher binding energy with increasing the oxygen flow proportion. The HfO2 films at high O2/Ar ratio had high transmissivity at the range of 400–1100 nm.