Fabrication of Periodic Nanostructures on Silicon Suboxide Films with Plasmonic Near-Field Ablation Induced by Low-Fluence Femtosecond Laser Pulses

Abstract

Silicon suboxide (SiOx, x ≈ 1) is a substoichiometric silicon oxide with a large refractive index and optical absorption coefficient that oxidizes to silica (SiO2) by annealing in air at ~1000 °C. We demonstrate that nanostructures with a groove period of 200–330 nm can be formed in air on a silicon suboxide film with 800 nm, 100 fs, and 10 Hz laser pulses at a fluence an order of magnitude lower than that needed for glass materials such as fused silica and borosilicate glass. Experimental results show that high-density electrons can be produced with low-fluence femtosecond laser pulses, and plasmonic near-fields are subsequently excited to create nanostructures on the surface because silicon suboxide has a larger optical absorption coefficient than glass. Calculations using a model target reproduce the observed groove periods well and explain the mechanism of the nanostructure formation.

In-process monitoring of femtosecond laser-induced periodic nanostructures on glass by using anti-reflective property

“…Superimposed multiple shots of femtosecond (fs) laser pulses form nanostructures with a period size of 1/13-1 of the laser wavelength λ on solid surfaces through ablation [1][2][3][4][5][6][7][8][9][10][11]. Since this phenomenon can be induced on a variety of materials such as titanium nitride [4], diamond-like carbon [4,11], silicon carbide [5], aluminum nitride [5], and sapphire [3,7], it is expected as a potential nanofabrication technique.…”

Editorial: Special Issue “Laser-Generated Periodic Nanostructures”

“…We aimed to attract both academic and industrial researchers in order to collate the current knowledge of nanomaterials and to present new ideas for future applications and new technologies. By 8 August 2021, 22 scientific articles have been published in the Special Issue [ 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ], see .…”

“…Three “Feature Papers” [ 15 , 16 , 17 ] were invited by the Guest Editors for the adequate framing of this Special Issue. An additional 19 papers were published as regular contributions [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ]. The publications in this Special Issue can generally be divided into three groups: (1) manuscripts related to self-organized laser-induced periodic surface structures [ 15 , 18 , 19 , 21 , 23 , 24 , 25 , 26 , 28 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ], (2) manuscripts related to interference-based periodic surface structuring [ 17 , 22 , 27 , 29 ], or (3) manuscripts combining both approaches [ 16 , 20 ].…”

“…Several publications focus on the relevance of chemical surface alterations during or after laser-processing, including studies of superficial oxidation on the formation of specific types of LIPSS [ 18 , 23 , 24 , 25 , 30 ], chemo-capillary effects in DLIP [ 29 ], or even post-laser irradiation effects due to reactions with the environment [ 30 ]. Other publications study the fundamental mechanisms of structure formation on the basis of experimental and theoretical plasmonic approaches [ 15 , 21 , 26 ], and also in combination with a two-temperature model [ 28 ], advanced molecular dynamics simulations [ 22 ], or multi-physical hydrodynamic continuum considerations [ 31 , 34 ]. Two articles investigate in vitro the growth of different types of biological cells (either scar-forming fibroblasts or bone-forming osteoblasts) on laser-generated micro- and nanostructures for medical applications [ 19 , 25 ].…”

“…Takaya et al [ 21 ] irradiated silicon suboxide (SiO x , x ≈ 1) with femtosecond laser pulses (800 nm, 100 fs, 10 Hz) in air. Upon multipulse irradiation at moderate fluences around 700 mJ/cm 2 , the formation of periodic nanogratings with a period in the range of 200–300 nm was observed.…”