Formation of micro/nano-metric holes/voids in Al<inf>2</inf>O<inf>3</inf>-coated boro-aluminosilicate glass by single pulse femtosecond laser irradiation

Abstract

In this paper, we report the formation of periodic array of micro/nano-scale holes/voids on the surface of and inside Al 2 O 3 -coated boro-aluminosilicate glass by means of single pulse femtosecond laser irradiation. The lowest diameter of the nanoholes printed on the Al 2 O 3 coating reaches down to 700 nm, whereas the lowest diameter of the voids inside the glass was 1.1 μm. The fabricated micro/nano-metric holes and voids show uniformity in size and shape throughout the sample area. We also investigate the surface property of the nanovoids' evolved glass surface. We don't observe any structure on the sample surface, when the voids have been evolved inside the glass sample. In addition, we investigate the formation mechanism of the micro/nano-holes or voids in our double-layer samples. We strongly believe that, the periodic micro/nano-voids array will be useful in fabricating various photonic/optical devices, especially, in spreading light.Index Terms-Femtosecond Laser, Al 2 O 3 -coated boroaluminosilicate glass, micro-holes/voids, nano-holes/voids.