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This chapter presents structural, optical, and magnetic properties of multiferroic LuFeO3 thin films, deposited on single crystal sapphire and YSZ substrates by an RF magnetron sputtering system. Growth temperature and annealing are found to be critical to stabilize hexagonal LuFeO3 thin films. Radio‐Frequency (RF) Magnetron Sputtering is relatively cost effective and one of the most commonly used methods for the deposition of oxides. An RF Magnetron Sputtering offers flexibility in terms of controlling the growth conditions, maintaining the stoichiometry, and a higher deposition rate. When the lattice strain is released due to annealing, the thin film can form bigger granular structures, as observed in the AFM image, by the nucleation process. The inset shows an example of the energy band edge fitting with the direct energy band gap model.
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This content will become publicly available on November 21, 2025
Optimization of superconducting niobium nitride thin films via high-power impulse magnetron sputtering
We report a systematic comparison of niobium nitride thin films deposited on oxidized silicon substrates by reactive DC magnetron sputtering and reactive high-power impulse magnetron sputtering (HiPIMS). After determining the nitrogen gas concentration that produces the highest superconducting critical temperature for each process, we characterize the dependence of the critical temperature on film thickness. The optimal nitrogen concentration is higher for HiPIMS than for DC sputtering, and HiPIMS produces higher critical temperatures for all thicknesses studied. We attribute this to the HiPIMS process enabling the films to get closer to optimal stoichiometry before beginning to form a hexagonal crystal phase that reduces the critical temperature, along with the extra kinetic energy in the HiPIMS process improving crystallinity. We also study the ability to increase the critical temperature of the HiPIMS films through the use of an aluminum nitride buffer layer and substrate heating.
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- PAR ID:
- 10556112
- Publisher / Repository:
- Institute of Physics
- Date Published:
- Journal Name:
- Superconductor Science and Technology
- ISSN:
- 0953-2048
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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