Surface structuring of optically transparent materials toward nanometer-scale resolution for the fabrication of optics and micro-chemical devices has been performed by UV and Vacuum UV laser Ablation. Recently, we have investigated a one-step method to fabricate a microstructure on the transparent materials such as silica glass, sapphire, and fluoride crystals by using a conventional UV laser under the atmospheric pressure. Laser-Induced Backside Wet Etching (LIBWE) fabricates microstructures with well-defined micro-patterns on the surfaces. Our idea of LIBWE is based on an indirect excitation onto the surface of materials by using ablation of organic solutions such as dye solution or toluene. Upon UV laser irradiation of the solution, shock wave and vapor bubble were formed and propagated. These transient phenomena are possible for the surface microstructuring of the materials.
