Effects of Micro Texture Processed by Picosecond Laser on Hydrophobicity of Silicon Carbide

To enhance the surface morphology and surface energy of silicon carbide to improve its surface wetting properties, picosecond pulsed laser surface treatment and chemical modification techniques were used, respectively. Additionally, a confocal laser microscope was used to analyze the microfabrication microstructure and the relationship between ablation pattern, laser properties, and processing parameters. Results demonstrated that ablation and remelting were the dominant factors influencing the laser processing effect. An inverted triangle-shaped ablation groove was observed due to ablation threshold of silicon carbide and Gaussian distribution of laser energy in the spot. Fluoroalkyl silane modifier used in the experiments could transform the silicon carbide surface from hydrophilic to hydrophobic. By varying processing parameters of pulsed laser treatment, contact angle of the modified silicon carbide surface increased to a maximum of 157 degrees. To better understand the effect of micro-textures on hydrophobicity, we developed a solid-liquid contact angle model based on the actual morphological parameters which elucidated the mechanism of contact angle variation with characteristic parameters of micro-textures, providing theoretical guidance for finding micro-textures with optimal hydrophobic performance.