[22p-C202-1~12] 6.4 Thin films and New materials

△ [22p-C202-10] Hydrophilicity Evaluation of Low Refractive Index SiO₂ Optical Thin Films by Electron Beam and Sputtering Evaporation part4

〇(M2)Mutsuki Ito¹, Takayuki Matsudaira², Hiroshi Murotani¹ (1.Tokai Univ., 2.SHINCRON Co.,Ltd.)

Keywords:optical thin film, hydrophilicity

We have developed a combination coating method in which DC pulse sputtering and EB deposition are operated simultaneously in the same vacuum chamber, and have succeeded in producing SiO₂ optical thin films with low refractive index. Ordinary SiO₂-coated glass is hydrophilic immediately after deposition, but becomes hydrophobic in about one week. In contrast, the combination coating method maintains the hydrophilic property even after one year from the deposition. The purpose of this study is to elucidate and evaluate the mechanism of the persistence of the hydrophilic function of the low refractive index SiO₂ optical thin films.