[21a-224A-1~10] 3.12 Nanoscale optical science and near-field optics

[21a-224A-10] Color control of Si-Based Printing with oxidation

〇Ikuto Hotta¹, Yusuke Nagasaki¹, Suzuki Masafumi¹, Junichi Takahara^1,2 (1.Osaka Univ., 2.Photonics Center)

Keywords:metasurface

We realized color control of Si-Based printing with oxidation. Reflection colors generated by Si nanostructure depend on structural geometry. Si surface is replaced by a SiO₂ layer, resulting in geometrical changes. Oxidized Si nanostructures exhibit wider tunability of reflection colors depending on the oxidation reaction. Combining color pixels enable the construction of an “invisible ink”. Invisible ink hides color information and is revealed by oxidation.