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We show that the concentration of oxygen defects trapped in Sc2O3 films by ion beam sputtering can be controlled by modifying deposition conditions. These defects play a role in the optical and structural properties of the thin film metal-oxides.

We have investigated the ion beam sputtering (IBS) of Y2O3 as an alternative to HfO2 for high index layers in interference coatings for high power lasers. We present results on structural and optical properties of Y2O3 deposited from an oxide target. The IBS Y2O3 films are amorphous with a surface roughness of

Small variations of oxygen partial pressure during the ion beam sputtering of metal oxides strongly influence the optical properties, causing an increase in the absorption loss and a decrease in laser damage fluence.

Scandium oxide is an attractive candidate for the engineering of interference coatings, although not widely explored. This paper describes the ion beam sputtering of Sc 2 O 3 . It is shown that the structural properties of the material are affected by the deposition conditions. Laser damage in different regimes of pulsewidths is investigated. These results show that the 1-on-1 laser damage fluence, in both the thermal and deterministic regimes, varies with deposition conditions but this is not the case for S-on-1, indicating that laser-induced defects are important.

Scandium oxide films were deposited using reactive dual ion beam puttering. At 1 micron, the refractive index of the films is 1.95 and the absorption loss is 18.5 ppm. X-ray photoelectron spectroscopy showed oxygen defects.

We discuss the physical and optical properties of Sc 2 0 3 single layers deposited by the dual ion beam sputtering technique at oxygen partial pressures ranging from 1.7 x 10 -5 to 5.1 × 10- 5 Torr. The films are amorphous with crystallite size ~10 nm and have surface roughness RMS values of 1.2 ± 0.3 nm. The refractive index at 1 μm is 1.95. Absorption loss is shown to be sensitive to the oxygen partial pressure during growth. Multiple-pulse damage experiments suggest that the scandia film deposited at the higher oxygen partial pressure accumulates laser-induced trap defects more slowly than the scandia film deposited in a lower oxygen partial pressure atmosphere.

In this work we use electron spin resonance (ESR) spectroscopy to investigate defects in dual ion beam sputtered HfO 2 and SiO 2 films. "As-grown" SiO 2 films exhibit an ESR feature consistent with an E' center associated with an oxygen vacancy previously reported. A similar feature with axial symmetry is seen in HfO 2 films. The defect giving rise to the HfO 2 ESR feature is distributed throughout the film. In addition, post process annealing of HfO 2 and SiO 2 films greatly reduces these defects.

We show that the concentration of oxygen interstitials trapped in Sc2O3 films by ion beam sputtering from metal targets can be controlled by modifying deposition conditions. We have identified point defects in the form of oxygen interstitials that are present in Sc2O3 films, in significantly high concentrations, i.e., ∼10(18) cm(-3). These results show a correlation between the increase of oxygen interstitials and the increase in stress and optical absorption in the films. Sc2O3 films with the lowest stress and optical absorption loss at 1 μm wavelength were obtained when using a low oxygen partial pressure and low beam voltage.