Optical micro/nanopatterning on curved Ti surfaces by transported, flexible micro-particle lens array

Abstract

Laser surface patterning by Contact Particle Lens Arrays (CPLA), utilizing near field enhancement, has been extensively utilized previously. In the process a solution of Contact Particles is spread on the substrate surface which dries to form a monolayer of CPLA on the substrate. The monolayer of the particles is then scanned by a laser to form patterns on the substrate. Despite of this extensive use, the deposition of CPLA has not yet been available on curved surfaces. In this paper, a novel technique for patterning on curved surfaces using CPLA is presented. In this technique, a hexagonal closed pack monolayer of SiO2 spheres is first formed by self assembly on a flat glass surface in the conventional manner. The formed monolayer of particles is then picked up by a flexible optically transparent sticky surface and placed on the substrate to be patterned. In this work, a 532 nm wavelength Nd:YVO4 laser was used to irradiate the substrate with the laser passing through the flexible, transparent, surface and the particles. The technique was validated for patterning of curved Titanium (Ti) surfaces. Experimental investigations are carried out to ascertain the properties of the patterns. In addition, the optical near-field distribution around the particles was numerically simulated.Laser surface patterning by Contact Particle Lens Arrays (CPLA), utilizing near field enhancement, has been extensively utilized previously. In the process a solution of Contact Particles is spread on the substrate surface which dries to form a monolayer of CPLA on the substrate. The monolayer of the particles is then scanned by a laser to form patterns on the substrate. Despite of this extensive use, the deposition of CPLA has not yet been available on curved surfaces. In this paper, a novel technique for patterning on curved surfaces using CPLA is presented. In this technique, a hexagonal closed pack monolayer of SiO2 spheres is first formed by self assembly on a flat glass surface in the conventional manner. The formed monolayer of particles is then picked up by a flexible optically transparent sticky surface and placed on the substrate to be patterned. In this work, a 532 nm wavelength Nd:YVO4 laser was used to irradiate the substrate with the laser passing through the flexible, transparent, surface a...