MetaMode Deposition of Niobium Oxide Thin Films Using a Broad-Beam Ion Source

Niobium oxide (Nb₂O₅) thin films were deposited under MetaMode using a new broad-beam ion source-enhanced magnetron sputtering. The ion source significantly reduced the required oxygen concentration from over 20% to ~7.5% to form fully stoichiometric Nb₂O₅ films. The MetaMode deposition rates were over three times higher than conventional reactive magnetron sputtering, which requires significantly higher oxygen concentrations. The film properties were characterized using UV-Vis spectroscopy, atomic force microscopy (AFM), scanning electron microscope (SEM), x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), four-point probe, and spectroscopic ellipsometry. The MetaMode deposited Nb₂O₅ thin films exhibited smoother surfaces, better optical transmittance, and denser morphology, while overcoming the disappearing anode effect in conventional reactive sputtering.