Research On The Fabrication And Properties Of Crystal Micro/Nano-Structures Based On Femtosecond Laser Processing And Ion Implantation

Ion irradiation and femtosecond laser ablation(FLA)are powerful technologies for micronano machining of transparent materials.Ion implantation technology is a mature semiconductor processing technology,which has been widely used in the production of optical communication devices and optical waveguides in recent years.In the process of ion implantation to form an optical waveguide,positively charged ions or protons are accelerated to a higher energy by the acceleration system and then bombard the surface of the target material,interacting with the nuclei and electrons in the target material to lose energy.Through the damage and defect mechanism,it finally stays at a depth of micron level on the surface of the target material and induces changes in the refractive index of the target material in the injection region to form a surface optical waveguide structure.With the rapid development of high-power pulsed femtosecond laser technology,pulsed femtosecond laser processing technology has been widely used.The interaction between femtosecond laser and matter has obvious advantages,such as non-thermal melting during processing,sub-micron processing,three-dimensional processing,wide range of processing materials,etc.The material surface processed by femtosecond laser has a variety of super-strong properties,such as super optical absorption efficiency,super hydrophilicity,super hydrophobicity,super electromagnetic radiation,super adhesion and desorption,etc.Therefore,it has been widely used in ultra-high-speed optical communication,new energy,nanoscience,biomedicine and other fields.In this paper,we report the selective surface processing of optical crystals by ion implantation and femtosecond laser ablation,namely ion-irradiation-assisted FLA.Based on the material modification effects in the ion-irradiated layers,different types of surface structuring characterized by grooves,nanogratings or sub-micron tracks are selectively induced by FLA.It is revealed that the ion-electron interaction induced localized lattice defects and related property modulation in target crystal play important roles in the formation and evolution of laser ablation regimes.Furthermore,the formation process of high-spatial-frequency nanograting is illustrated with the periodical enhancement of local field through the excitation of surface plasmon polaritons,which is experimentally supported through the measurements of transmission electron microscope and energy-dispersive spectroscopy.Our findings further clarify the ion-and laser-matter interactions and the correlation between these processes and surface modifications.The approach proposed in this work shows potential applications in the rapid fabrication of hybrid and versatile surface structures on crystalline materials.