Ultrafast Laser Texturing of Copper Metal Surface: Superhidrophobicity and UV-NIR Reflectance Properties
Yuliati Herbani (a*), Nursidik Yulianto (a,b), Kirana Yuniati Putri (a), Affi Nur Hidayah (a) Hutomo Suryo Wasisto (b)

a) Research Center for Physics, Indonesian Institute of Sciences, Jl Riset, Gedung 442, Kawasan Puspiptek Serpong, Setu, Tangerang Selatan, Banten, Indonesia, 15314
*yuliati.herbani(at)lipi.go.id

b) Laboratory for Emerging Nanometrology (LENA), Technische Universitat Braunschweig, Langer Kamp 6, D38106 Braunschweig, Germany

Abstract

Functional surfaces are key components of nearly every mechanical device and they have become a special focus in both academia and industry. The no contact, one step, direct, and maskless laser surface texturing technique is one of the most encouraging approaches for realizing the surface functions. We use a high power and high repetition rate ultrafast laser system to produce nano structures on metal surfaces. We demonstrate that metal surface nano structures and correspondingly their wetting property and the optical responses can be facilely tailored by simple controlling the ultrafast laser processing parameters. A surface nanostructures with nano particles of tens to hundreds nm have been fabricated on copper (Cu) surfaces. The wetting property was found to be superhydrophobic with a maximum contact angle of 143.2. Surface reflection of copper surfaces has been tuned from 10% to 90% in spectra level from UV to NIR in spectrum range, with unique optical properties like visible selective reflection, linear changing reflection, band reflection, and broadband absorption being achieved. The formation processes of those particle structures as well as the underlying mechanisms for their wetting property and optical responses are discussed.

Keywords: femtosecond laser texturing- superhydrophobicity- UV-NIR reflectance

Topic: Materials Physics