scholarly journals Structuring and functionalization of non-metallic materials using direct laser interference patterning: a review

Nanophotonics ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Lucinda Mulko ◽  
Marcos Soldera ◽  
Andrés Fabián Lasagni

Abstract Direct laser interference patterning (DLIP) is a laser-based surface structuring method that stands out for its high throughput, flexibility and resolution for laboratory and industrial manufacturing. This top–down technique relies on the formation of an interference pattern by overlapping multiple laser beams onto the sample surface and thus producing a periodic texture by melting and/or ablating the material. Driven by the large industrial sectors, DLIP has been extensively used in the last decades to functionalize metallic surfaces, such as steel, aluminium, copper or nickel. Even so, DLIP processing of non-metallic materials has been gaining popularity in promising fields such as photonics, optoelectronics, nanotechnology and biomedicine. This review aims to comprehensively collect the main findings of DLIP structuring of polymers, ceramics, composites, semiconductors and other non-metals and outline their most relevant results. This contribution also presents the mechanisms by which laser radiation interacts with non-metallic materials in the DLIP process and summarizes the developed surface functions and their applications in different fields.

2007 ◽  
Vol 1054 ◽  
Author(s):  
Diego Acevedo ◽  
Andrés Lasagni ◽  
Cesar Barbero ◽  
Frank Muecklich

ABSTRACTNovel surface engineering techniques of polymeric materials are essential to produce advanced topographies which could for example serve to modulate cell and tissue response in bio-materials. Direct Laser Interference Patterning (DLIP) permits the fabrication of repetitive arrays and microstructures by irradiation of the sample surface with coherent beams of light. Furthermore, the most important advantage of this method is that no additional process steps are required in comparison with other top-down or bottom-up techniques. In this study, we report a novel method for the advanced design of architectures in polymers using a single step process, as well as photo-activation of polymers with low absorption coefficient using a second polymer with relative high absorption coefficient. Previously calculated interference patterns using the well known interference theory could be directly produced on polymeric surface. Moreover, the cross-section of the structured polymers changes depending on the intensity of the laser beams, and photomachinability of polymers is highly influenced by laser wavelength. High absorbance of the polymeric materials at specific wavelengths allows the reduction of the laser intensity required to achieve a determined structure depth. For (60:40 %) polymethylmetacrylate/polystyrene copolymer substrate, different structures types were observed depending on the laser intensity including swelling and ablation of the material.


Langmuir ◽  
2020 ◽  
Vol 36 (45) ◽  
pp. 13415-13425 ◽  
Author(s):  
Daniel W. Müller ◽  
Anne Holtsch ◽  
Sarah Lößlein ◽  
Christoph Pauly ◽  
Christian Spengler ◽  
...  

Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 679
Author(s):  
Daniel Sola ◽  
Stephan Milles ◽  
Andrés F. Lasagni

Refractive index modification by laser micro-structuration of diffractive optical devices in ophthalmic polymers has recently been applied for refractive correction in the fields of optics and ophthalmology. In this work, Safrofilcon-A hydrogel, used as soft contact lenses, was processed by direct laser interference patterning (DLIP) to fabricate linear periodic patterns on the surface of the samples. Periodic modulation of the surface was attained under two-beam interference by using a Q-switched laser source with emission at 263 nm and 4 ns pulse duration. Features of processed areas were studied as a function of both the interference spatial period and the laser fluence. Optical confocal microscopy used to evaluate the topography of the processed samples showed that both structured height and surface roughness increased with laser fluence. Static water contact angle (WCA) measurements were carried out with deionized water droplets on the structured areas to evaluate the hydration properties of DLIP structures. It was observed that the laser structured areas induced a delay in the hydration process. Finally, microstructural changes induced in the structured areas were assessed by confocal micro-Raman spectroscopy showing that at low laser fluences the polymer structure remained almost unaltered. In addition, Raman spectra of hydrated samples recovered the original shape of areas structured at low laser fluence.


2021 ◽  
Author(s):  
Mikhael El-Khoury ◽  
Bogdan Voisiat ◽  
Tim Kunze ◽  
Andrés Fabián Lasagni

Abstract Uniform periodic microstructures formation over large areas is generally challenging in Direct Laser Interference Patterning (DLIP) due to the Gaussian laser beam intensity distribution inherent to most commercial laser sources. In this work, a diffractive fundamental beam-mode shaper (FBS) element is implemented in a four-beam DLIP optical setup to generate a square-shaped top-hat intensity distribution in the interference volume. The interference patterns produced by a standard configuration and the developed setup are measured and compared. In particular, the impact of both laser intensity distributions on process throughput as well as fill-factor is investigated by measuring the resulting microstructure height with height error over the structured surface. It is demonstrated that by utilizing top-hat-shaped interference patterns, it is possible to produce on average 44.8 % deeper structures with up to 60 % higher homogeneity at the same throughput. Moreover, the presented approach allows the production of microstructures with comparable height and homogeneity compared to the Gaussian intensity distribution with increased throughput of 53%.


Sign in / Sign up

Export Citation Format

Share Document