The influence on the internal stress and optical properties of Nb<sub>2</sub>O<sub>5</sub> thin films with ion-beam energy was investigated. Nb<sub>2</sub>O<sub>5</sub> thin films were deposited on unheated glass substrates by means of ion-beam sputtering with different ion-beam voltage, <i>V</i><sub><i>b</i></sub>. The refractive index, extinction coefficient, and surface roughness were found to depend on the ion-beam energy. The stresses in thin films were measured by the phase-shifting interferometry technique. The film stress was also found to be related to <i>V</i><sub><i>b</i></sub>, and a high compressive stress of −0.467 GPa was measured at <i>V</i><sub><i>b</i></sub> = 850 V. The Nb<sub>2</sub>O<sub>5</sub>–SiO<sub>2</sub> multilayer coatings had smaller average compressive stress as compared with single-layer Nb<sub>2</sub>O<sub>5</sub> film.
© 2002 Optical Society of America
Cheng-Chung Lee, Chuen-Lin Tien, and Jin-Cherng Hsu, "Internal Stress and Optical Properties of Nb2O5 Thin Films Deposited by Ion-Beam Sputtering," Appl. Opt. 41, 2043-2047 (2002)