Formation of Periodic Micro/nano-holes Array in Boro-aluminosilicate Glass by Single-pulse Femtosecond Laser Machining

Abstract

This paper reports the formation of periodic micro/nano-holes on the surface of as well as inside boro-aluminosilicate glass by controlling the irradiation conditions of a single-beam femtosecond laser. The laser beam is focused inside the glass sample to fabricate closely spaced periodic high aspect ratio nano-scale voids' array. The lowest diameter of the nanovoids reaches down to 650 nm. We also pattern periodic microholes' array on the surface of the sample glass by focusing the laser beam on the front surface of the glass substrate. The fabricated micro/nano-metric holes and voids are very uniform in size and shape throughout large sample area. We also investigate the surface properties of the nanovoids' evolved glass surface. We don't observe any significant variation in surface morphology and materials' composition among the bare glass and nanovoids' engraved glass surface. Moreover, we qualitatively explain the formation mechanism of high aspect ratio nanovoids inside the glass substrate.