Tunable Electrical Properties of Vanadium Oxide by Hydrogen-Plasma-Treated Atomic Layer Deposition.

In this study, a plasma-modified process was developed to control the electrical properties of atomic layer deposition (ALD)-grown vanadium dioxide (VO), which is potentially useful for applications such as resistive switching devices, bolometers, and plasmonic metamaterials. By inserting a plasma pulse with varying H gas flow into each ALD cycle, the insulator-to-metal transition (IMT) temperature of postdeposition-annealed crystalline VO films was adjusted from 63 to 78 °C. Film analyses indicate that the tunability may arise from changes in grain boundaries, morphology, and compositional variation despite hydrogen not remaining in the annealed VO films. This growth method, which enables a systematic variation of the electronic behavior of VO, provides capabilities beyond those of the conventional thermal ALD and plasma-enhanced ALD.