Hierarchical Micromold Structuring via 2PP Micro-Stereolithography

Inspired by nature, a common way to create hydrophobic surfaces is by introducing hierarchical and fractal microstructures on surface. While plenty of studies have demonstratedcreating PDC (polymer derived ceramic) for several applications include SiC-fiber for composite materials and cantilever in ceramic MEMs, no research from the author’s knowledge is devoted to creating hydrophobic PDC surface by fabricate micro size array-like structure on PDC. Therefore, fabricate hydrophobic PDC surface is the main goal of the project. To achieve the idea, a novel approach is introduced and presented in the report. The approach combines micro molding of PDC and 3D printing hydrophobic surface. By exploiting micro-stereolithography base on Two Photon Polymerization, the project first printed various 3D structure including fractal Sierpinski tetrahedron, pyramid, biomimic arrays and QR codes. The printed photoresists show very well define structures by using OM characterization and the hydrophobicity of structure were verified by drop shape analyser. The designed micro molds were printed on the KOH etched mold for PDC molding. In the end, using this novel method, first ever micro-featured PDC were successfully replicated. Although the hydrophobicity for pyramid arrays on PDC is not yet verified, several improvements are provided to optimize future experiment.