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Titanium nitride ( TiN x ) is regarded as a kind of promising plasmonic material for its high performances. We studied the influence of nitrogen partial pressure p n and deposition temperature T d on the structural and plasmonic properties of the TiN x thin films prepared by ion beam assisted deposition (IBAD). The results show that IBAD is an effective method to tailor the plasmonic properties of TiN x films in visible and near-IR region. The plasmonic properties of the films have significant T d and p n dependence. Higher p n and lower T d can reduce the plasma frequency and the plasmon resonance. Higher p n and higher T d can reduce the optical loss of the samples. The modification of the plasmonic properties is related to the variation of nitrogen content.

Ion beam assisted titanium nitride (TiN) film has attracted much attention because its fast texture and high conductivity can be effectively applied in all-conductive superconducting coated conductor. In this work, TiN films were prepared by ion beam sputtering deposition from a metal titanium target. Effects of sputtering ion energy, assisting ion energy, assisting ion current and deposition temperature on the orientation and surface morphology were analyzed. The results indicate that assisting ion is an important factor in orientation selection, and high assisting ions and low assisting ion current could enhance the crystallinity. However, too high assisting ion energy and current can destroy the crystallinity in IBAD–TiN. This orientation selection can be attributed to the energy exchange between assisting ions and adatoms.

Undoped and Cu-doped ZnO (ZnO:Cu) thin films were prepared using magnetron co-sputtering. Effects of substrate temperature $$T_{s}$$ on their structural, electrical and optical properties were comparatively investigated using X-ray diffraction, atom force microscopy, and ultraviolet visible spectrophotometer. ZnO:Cu thin films with different doping content were prepared and studied in order to investigate the effects of Cu-doping content. The results show that all the films exhibit a single phase (002)-oriented hexagonal wurtzite structure. Higher $$T_{s}$$ enhances the crystallinity and reduces the compressive stress of the films. Cu-doping and increasing $$T_{s}$$ lead to rougher surface and larger granules. The resistivity of both the ZnO and ZnO:Cu films increases with $$T_{s}$$ . Interestingly, optical band gap $$E_{g}$$ of ZnO:Cu films increases significantly with $$T_{s}$$ , while $$E_{g}$$ of undoped film is not obviously influenced by $$T_{s}$$ . Cu-doping content is an important factor affecting the physical properties of ZnO:Cu thin films. In our experiments, Cu-doping composition sightly decreases with $$T_{s}$$ increasing. Cu-doping reduces the resistivity, leads to the red-shift of absorption edge, and narrows $$E_{g}$$ of ZnO thin films.

Nitrogen doped ZnO films were prepared by magnetron sputtering. We studied the influence of nitrogen partial pressure pn and oxygen partial pressure po on the microstructure, morphology and optical properties of the thin films. The results show that different defects influence the structure and optical behavior of the films. Doping-related tensile stress turns compressive, owing to a different N-doping form in the films. Red-shift of absorption edge was observed with increasing pn and decreasing po. Band-gap narrowing is improved by increasing nitrogen substitute and oxygen vacancies.

Undoped and Cu-doped zinc oxide (ZnO:Cu) films were deposited on glass substrates by magnetron sputtering at different oxygen partial pressures po. Microstructure, surface morphology, resistivity, and optical properties were systematically investigated. The results show that lower po can degrade the crystallinity, and reduce the band gap. Undoped ZnO films are not obviously influenced by po, especially at high oxygen pressure. In contrast, ZnO:Cu thin films are remarkably affected by po. This work suggests that oxygen vacancies play an important role in modifying properties and allows us to accurately modulate the band gap of the ZnO-based films.

Ion assisted MgO film has attracted much attention because of its extensive application. Most of the related work was focused on ion assisted evaporation. In this work, MgO thin films were prepared by ion beam sputtering deposition without oxygen gas present. Effects of sputtering energy, deposition temperature, deposition angle and assisting ions on the orientation were analyzed. The orientation of MgO films is found strongly dependent on these parameters. As the parameters vary, (1 1 0), (1 1 1), (1 0 0) orientation is preferred in turn. The results surface morphology indicate that assisting ions can flatten the film surface and enhance the crystallinity. This orientation selection can be attributed to the energy exchange between assisting ions, deposition atom and adatoms. The results give the possibility to modulate the orientation to meet different demands.

ZnO-based resistive switching device Ag/ZnO/TiN, and its modified structure Ag/ZnO/Zn/ZnO/TiN and Ag/graphene/ZnO/TiN, were prepared. The effects of inserted Zn layers in ZnO matrix and an interface graphene layer on resistive switching characteristics were studied. It is found that metal ions, oxygen vacancies, and interface are involved in the RS process. A thin inserted Zn layer can increase the resistance of HRS and enhance the resistance ratio. A graphene interface layer between ZnO layer and top electrode can block the carrier transport and enhance the resistance ratio to several times. The results suggest feasible routes to tailor the resistive switching performance of ZnO-based structure.