HfO2 thin films prepared by ion beam assisted deposition

Hafnium oxide thin films were prepared using a high-energy ion beam assisted deposition (IBAD) system. Oxygen ion energy was varied the range of 1–20 keV, which is much wider than those in other IBAD works. The transport ratio (TR), defined as the ratio between the hafnium arrival rate and the oxygen ion dose, was varied at 1 and 10. The substrate was cooled by water. The structures of the films were characterized using X-ray diffraction and the morphology of films was observed by field emission scanning electron microscope. In this research, films with cubic, tetragonal and monoclinic structures, or their mixtures were obtained, and their structures were dependent on ion beam energy and TR.