Etching-assisted femtosecond laser modification of hard materials

Abstract

With high hardness, high thermal and chemical stability and excellent optical performance, hard materials exhibit great potential applications in various fields, especially in harsh conditions. Femtosecond laser ablation has the capability to fabricate three-dimensional micro/nanostructures in hard materials. However, the low efficiency, low precision and high surface roughness are the main stumbling blocks for femtosecond laser processing of hard materials. So far, etching-assisted femtosecond laser modification has demonstrated to be the efficient strategy to solve the above problems when processing hard materials, including wet etching and dry etching. In this review, femtosecond laser modification that would influence the etching selectivity is introduced. The fundamental and recent applications of the two kinds of etching assisted femtosecond laser modification technologies are summarized. In addition, the challenges and application prospects of these technologies are discussed.

3D Manufacturing of Glass Microstructures Using Femtosecond Laser

“…There are many laser glass processing techniques based on nonlinear light-matter interactions, and by inducing different types of modification it is possible to change the method by which we perform the processing of glass. Type I modification can be used for for smooth laser refractive index modification [ 40 ] and waveguides formation in glass [ 47 , 48 ], type II can be used for Q-plate manufacturing, while post-processing etching step of modification is necessary for selective laser etching (SLE) [ 49 ]. Meanwhile, type III modification is used for laser ablation [ 35 ] and welding [ 50 ].…”

Plastic deformation as nature of femtosecond laser writing in YAG crystal

“…Recently a new disruptive technology of a photonic crystal waveguide in YAG crystals has been proposed 9,54,55 . It is based on the phenomenon of a dramatic etching rate increase in the tracks inscribed by a femtosecond laser, however the theory of this phenomenon is not developed yet 56 . We believe that the etching rate increase is due to an anomalous multiplication of dislocations leading to their agglomeration accompanied by formation of nanocracks.…”

Femtosecond Laser Structuring for Flexible Surface-Enhanced Raman Spectroscopy Substrates

“…When the period is too large, the micro-/nano-structure is not enough. Therefore, an appropriate period is needed [63][64][65]. As a result, the detailed Fs laser processing parameters are as follows: λ = 1030 nm, the pulse duration = 290 fs, the repetition rate = 200 kHz, the laser power ≈ 1500 mW, respectively.…”