Laser plasma-induced damage characteristics of Ta2O5 films

As a material that exhibits a high refractive index and an excellent chemical stability, Ta2O5 is widely used in the microelectronics and chemical industries. In this study, we analyzed the effect of plasma shock waves on Ta2O5 thin films. The experimental results showed that the damage characteristics of the film include thermal ablation, surface cracks, and peeling off from the substrate owing to the repeated action of the pulse. Coating characterization before and after exposure to laser plasma was performed using UV-Vis spectroscopy, energy dispersive spectroscopy (EDS), Raman spectroscopy, and X-ray diffraction. With the increase in the light absorbed by the ablated products, the transmittance of the film decreased after damage, and the Raman spectrum and X-ray diffraction pattern of the sample indicated that the film changes from an amorphous to a crystalline structure owing to the action of the high-temperature and high-pressure plasma. The EDS analysis results indicated that the oxygen content in the film decreases because of the damage inflicted to its structure.