CC BY
13LP-I-10
Laser micro- and nanostructuring of solids by sub-nanosecond laser pulses
E. V. Barmina1
1Prokhorov General Physics Institute of the Russian Academy of Sciences, Wave Research Center, Moscow, Russian Federation
Controlling the interactions of light with matter is crucial for the success and scalability of materials processing applications at micro and nano-scale. When lasers are used as light sources, the optimal interplay between the laser and material parameters may allow the fabrication of features with dimensions of the order or smaller than the laser wavelength diffraction limit. This report will focus on laser-assisted micro/nano structuring (NS) of surfaces and controlling materials properties via this process. A variety of different material responses have been achieved depending on the material system and the laser parameters, allowing processes to be designed and optimized to permanently alter the material's surface chemistry, crystal structure, and morphology to suite its desired function. The unique aspect of this for many applications is that the material modifications can occur over many different length scales, adding complexity to the surface and a new dimension to surface optimization. As a result, direct irradiation of materials by ultrafast laser pulses in controlled atmosphere often induces modifications leading to complex micro- and nano-scale surface structures, which are often found to have different and by far superior properties to those of the bulk materials. Indeed, we demonstrate that laser micro/nanostructured materials can be exploited for diverse emerging applications opening up new, exciting possibilities. Furthermore, laser initiation of phase transitions at the solid-liquid interface results in the formation of self-organized micro- and/or nanostructures and high-spatial-frequency laser-induced periodic surface structures (HSFL) on the solid surface.
Formation of NS is assigned to the instability of evaporation of the liquid that surrounds the irradiated target. In comparison HSFL occurre due to the development of thermocapillary instability of the melt layer on the target surface. The morphology of NS generated on various metallic as well as non-metallic bulk solids is studied as a function of laser parameters and target material.
The aim of this report to show the evolution morphology of the surface from micro (1-10 mm) to nanoscale (till 10 nm) as different unique types of micro and nanostructures are formed under laser ablation of target. Laser nanotechnologies presented in this topic found a lot of applications such as enhancement of external applied field up to 104 times, change of antifriction properties, development of the structured surface as ultrablack absorbers with unique optical properties. Besides presenting recent advances on the elucidation of the possible mechanisms behind the formation of the structures obtained by these techniques, it will also delineate existing limitations and discuss emerging possibilities and
future prospects. Fig. 1.
