Surface Micromachining by Micro Slurry-jet

Abstract

The surfaces of a lotus leaf and moth eye have fine structures that produce a water-repellent effect or reflection suppression. The purpose of this study was to explore the use of surface micromachining to create a bio-inspired surface on artificial materials. A micro slurry-jet was proposed as a removal process for a Co-28Cr-Mo alloy, an acrylic resin and a glass surface. The micro slurry-jet is a wet blasting technique that uses alumina particles as an abrasive medium along with compressed air and water to create fine structures. Although the micro slurry-jet has ultraprecision machining ability in the order of nanometers in the orthogonal direction on a material surface, only sub-millimetric machining accuracy in the parallel direction was realized because of the size limitation of the slurry-jet injection nozzle. A mask operation using microelectromechanical technology, which prevents the removal process by the micro slurry-jet, was also adopted to increase the machining accuracy of a material surface. These methods provided few restrictions on the kind of materials that could be created on a bio-inspired surface, and reduced the pre- and post-treatments of the material surfaces.