Study of High Transmittance of SiO[sub.2]/Nb[sub.2]O[sub.5] Multilayer Thin Films Deposited by Plasma-Assisted Reactive Magnetron Sputtering

• Published in: Applied sciences 2023-12, Vol.13 (24)
• Main Authors: Kim, Soyoung, In, Jung-Hwan, Kim, Seon Hoon, Han, Karam, Lim, Dongkook, Hwang, Yun Sik, Lee, Kyung Min, Choi, Ju Hyeon
• Format: Article
• Language: English
• Subjects: Dielectric films; Superconductors; Thin films
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app132413271

SiO[sub.2]/Nb[sub.2]O[sub.5] multilayer thin films were designed for the special application of an aviation lighting system emitting green light. For optical components in this system to meet requirements such as a high transmittance and durability, SiO[sub.2]/Nb[sub.2]O[sub.5] multilayer thin films of 60 individual layers were fabricated by a plasma-assisted reactive magnetron sputtering method. As a result, the transmittance spectra were confirmed to have a flat top surface and a square bandwidth. The transmittances of the SiO[sub.2]/Nb[sub.2]O[sub.5] multilayer thin films in the range of 500 nm to 550 nm was approximately 96.14%. The reason for high transmittance was attributed to the almost matching between the designed and fabricated SiO[sub.2]/Nb[sub.2]O[sub.5] multilayer thin films. It was found that there was little difference in the total thickness between the designed and fabricated SiO[sub.2]/Nb[sub.2]O[sub.5] multilayer thin films without interlayer diffusion. The surface roughness and hardness of the SiO[sub.2]/Nb[sub.2]O[sub.5] multilayer thin films on a glass substrate was 2.32 nm ± 0.19 nm and 6.6 GPa, respectively. These results indicate that SiO[sub.2]/Nb[sub.2]O[sub.5] multilayer thin films can be applied not only to the optical filters used in aviation lighting devices, but also to various optics applications because of high transmittance.