Formation of the Submicron Oxidative LIPSS on Thin Titanium Films During Nanosecond Laser Recording

Abstract

Laser-induced periodic surface structures (LIPSSs) spontaneously appearing on the laser-treated (melted or evaporated) surfaces of bulk solid materials seem to be a well-studied phenomenon. Peculiarities of oxidative mechanisms of LIPSS formation on thin films though are far less clear. In this work, the appearance of oxidative LIPSSs on thin titanium films was demonstrated under the action of commercially available nanosecond-pulsed Yb-fiber laser. The temperature and energy regimes favoring their formation were revealed, and their geometric characteristics were determined. The period of these LIPSSs was found to be about 0.7 λ, while the modulation depth varied between 70 and 110 nm, with high stability and reproducibility. It was shown that LIPSS orientation is rather easily manageable in the regimes of our interest, which could provide a way of controlling their properties.

Laser Thermochemical High-Contrast Recording on Thin Metal Films

“…Laser thermochemical recording on thin Ti films requires a rather long (up to ms) exposure to obtain through oxidation due to the feedback complexities of the oxidation process [ 25 , 26 , 27 , 30 , 31 , 32 , 33 , 34 ]. However, in order to avoid the accumulation of heat in the film and its thermal damage, it is preferable to expose the film by several thousand consecutive picosecond pulses with a low repetition rate (around 1000 Hz or lower) [ 34 ].…”

“…Recently, various technical combinations of the thermochemical laser recording method were realized on Ti films: the direct action of a focused scanning laser beam [ 24 , 25 ], the formation of thermochemical laser-induced periodic surface structures (LIPSSs) [ 21 , 23 , 26 , 27 ], or the thermochemical registration of an interference pattern [ 28 , 29 ], including researches by our own group. However, to this day, there is no confirmed theoretical model that could predict the optimal laser processing parameters (e.g., number of laser pulses or fluence) required to fabricate the structure of minimum width while maintaining the maximum contrast.…”

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 ].…”