Research On Composite Functional Micro-nano Structure Of Transparent Material Surface Based On Laser Interference Lithography

The surface of composite functional transparent materials has broad application scenarios in fields such as solar cells,optical lenses,screens,photonic crystals,and other areas that require high light energy utilization.However,the efficiency of preparing the surface of composite functional transparent materials has always been the main obstacle that limits its large-scale and commercial use.In this study,a laser interference lithography step-by-step splicing system was constructed to create a large-area periodic micro-nano structure on the surface of stainless steel using the double-beam single-exposure method of direct laser interference lithography.By adjusting parameters such as laser energy and pulse number of the Gaussian beam,a stainless steel metal template with high resolution and uniform light and dark stripes was obtained.The periodic micro-nano structure on the stainless steel metal template was transferred to a PET film coated with silica nanoparticles using the solid-state isothermal hot pressing method.This method not only improved the processing efficiency of hot embossing but also prevented secondary crystallization of the PET film,which could affect its light transmittance.The PET films prepared at different embossing temperatures were characterized using scanning electron microscopy(SEM),and the experimental results demonstrated improved deformability of crystalline polymers near the heat distortion temperature.The contact angle of the PET film prepared under different embossing pressures was measured using a contact angle measuring instrument,and it was found that the PET film prepared at a pressure of 20 MPa and a temperature of95℃ exhibited the best hydrophobicity,with a maximum contact angle of 152.3°.The reflectance of the PET film prepared at different embossing temperatures was measured using an angle-resolved spectroscopic microscope,and the experimental results showed that the PET film prepared at a pressure of 20 MPa and a temperature of 95℃ had a minimum reflectance of 7.5%.In summary,this study successfully prepared a transparent material surface with a superhydrophobic anti-reflection composite function,exhibiting a contact angle of 152.3° and a reflectivity of 7.5%.This study provides a large-area and high-efficiency method for preparing the surface of composite functional transparent materials.The area and efficiency of the prepared composite functional transparent material surface depend on the area of the metal template and the efficiency of thermal embossing.Additionally,this method proposed in this study offers a new approach for preparing the surface of composite functional transparent materials.