Laser micro structuring on a Si substrate for improving surface hydrophobicity

• Published in: Journal of micromechanics and microengineering 2009-08, Vol.19 (8), p.085025-085025 (6)
• Main Authors: Wang, X C, Wu, Linda Y L, Shao, Q, Zheng, H Y
• Format: Article
• Language: English
• Subjects: Applied sciences; Electronics; Exact sciences and technology; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Mechanical engineering. Machine design; Mechanical instruments, equipment and techniques; Microelectronic fabrication (materials and surfaces technology); Micromechanical devices and systems; Physics; Precision engineering, watch making; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices
• ISSN: 0960-1317; 1361-6439
• DOI: 10.1088/0960-1317/19/8/085025

355 nm diode-pumped solid-state (DPSS) ultraviolet (UV) laser-induced surface texturing on a Si substrate is reported in this paper. Surface patterns consisting of miro-size pits were produced by direct laser ablation. By fine-tuning key process variables such as laser beam fluence, pulse number, and beam spot separation, uniform and repeatable micropatterns with nano features have been generated on the Si surface. Under appropriate optimum laser conditions, the surface contact angle of the Si substrate was increased from 64.2 deg to 97.5 deg. Furthermore, it was demonstrated that the laser textured Si substrate could be used as a template for imprinting. After imprinting the laser-induced pattern onto the sol-gel film, the sol-gel film surface contact angle was increased by nearly 30 deg up to 138 deg due to two-tier rough surfaces.