Study for Laser Controlled Fabrication of Micro/Nano-Structures of Silicon Based on Multi-Physics Model

This work proposes a detailed process of micro/nano-structure surface modification in relation to temperature field. In this paper, a femtosecond laser is used to induce the surface morphology of a silicon substrate. We provide a new method for the fabrication of a micro/nano-cantilever probe by controlling the aspect ratio of the silicon surface morphology. A computational method is used to investigate the mechanical behaviors of early perturbation to late-stage structure. A diffuse interface model is employed to describe the evolution and provide a general framework. The theoretical model of femtosecond laser control surface morphology is verified by the experiments. For systematic study, the model involves the interface energy and kinetics of diffusion. This method provides an effective way to improve the sensitivity of micro/nano-cantilever sensors.

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Multipulse irradiation of silicon by femtosecond laser pulses: Variation of surface morphology

Applied Surface Science ◽

10.1016/j.apsusc.2011.11.121 ◽

2012 ◽

Vol 258 (8) ◽

pp. 3589-3597 ◽

Cited By ~ 13

Author(s):

S. Lugomer ◽

A. Maksimović ◽

B. Farkas ◽

Z. Geretovszky ◽

T. Szörényi ◽

...

Keyword(s):

Femtosecond Laser ◽

Surface Morphology ◽

Laser Pulses ◽

Femtosecond Laser Pulses

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Effect of metal surface morphology on nano-structured patterns induced by a femtosecond laser pulse and its experimental verification

Chinese Optics Letters ◽

10.3788/col201816.073202 ◽

2018 ◽

Vol 16 (7) ◽

pp. 073202

Author(s):

Haiying Song Haiying Song ◽

Shengwang Tan Shengwang Tan ◽

Elshaimaa M. Emara Elshaimaa M. Emara ◽

Yanjie Zhang Yanjie Zhang ◽

Shibing Liu Shibing Liu ◽

...

Keyword(s):

Laser Pulse ◽

Femtosecond Laser ◽

Surface Morphology ◽

Metal Surface ◽

Femtosecond Laser Pulse ◽

Experimental Verification

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A geometric diffuse-interface method for droplet spreading

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2019.0222 ◽

2020 ◽

Vol 476 (2233) ◽

pp. 20190222

Author(s):

Darryl D. Holm ◽

Lennon Ó Náraigh ◽

Cesare Tronci

Keyword(s):

Numerical Simulations ◽

Large Scale ◽

Computational Cost ◽

Computational Method ◽

Diffuse Interface ◽

Precursor Film ◽

Droplet Spreading ◽

Wetting Fluids ◽

Thin Film Equation ◽

Wetting Fluid

This paper exploits the theory of geometric gradient flows to introduce an alternative regularization of the thin-film equation valid in the case of large-scale droplet spreading—the geometric diffuse-interface method. The method possesses some advantages when compared with the existing models of droplet spreading, namely the slip model, the precursor-film method and the diffuse-interface model. These advantages are discussed and a case is made for using the geometric diffuse-interface method for the purpose of numerical simulations. The mathematical solutions of the geometric diffuse interface method are explored via such numerical simulations for the simple and well-studied case of large-scale droplet spreading for a perfectly wetting fluid—we demonstrate that the new method reproduces Tanner’s Law of droplet spreading via a simple and robust computational method, at a low computational cost. We discuss potential avenues for extending the method beyond the simple case of perfectly wetting fluids.

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Influence of surface morphology on processing of C/SiC composites via femtosecond laser

Composites Part A Applied Science and Manufacturing ◽

10.1016/j.compositesa.2017.07.031 ◽

2017 ◽

Vol 102 ◽

pp. 117-125 ◽

Cited By ~ 20

Author(s):

Zhaoyang Zhai ◽

Wenjun Wang ◽

Jie Zhao ◽

Xuesong Mei ◽

Kedian Wang ◽

...

Keyword(s):

Femtosecond Laser ◽

Surface Morphology ◽

Sic Composites

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Periodic Nano-Structure Formation with Femtosecond Laser Ablation and Patterning of Silicon

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.275-277.2186 ◽

2013 ◽

Vol 275-277 ◽

pp. 2186-2189

Author(s):

Jian Ting Xu ◽

Dong Qing Yuan

Keyword(s):

Femtosecond Laser ◽

Pulse Length ◽

Femtosecond Laser Ablation ◽

Objective Lens ◽

Micro Machining ◽

Nano Structure ◽

Laser Micro Machining ◽

Silicon Bulk ◽

The Relationship ◽

Focused Beam

Regular micro-apparatus which covered with periodic nano-hole, nano-ridge and ripple structures on silicon bulk were formed by laser micro-machining with tightly focused beam of the femtosecond laser with wavelength of 800 nm, repetition rate of 1 kHz and the pulse length of 130 fs in air. The periodic nano-hole structures which focus with a 20× focusing objective lens (NA = 0.4) is reported. Investigating the relationship between the width of structures and the speed of processing.

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Особенности наноструктурирования поверхности кремния в результате ее сверхбыстрого нагрева фемтосекундным лазерным импульсом в воде

Письма в журнал технической физики ◽

10.21883/pjtf.2018.14.46345.17271 ◽

2018 ◽

Vol 44 (14) ◽

pp. 58

Author(s):

С.А. Ромашевский

Keyword(s):

Atomic Force Microscopy ◽

Laser Pulse ◽

Femtosecond Laser ◽

Surface Morphology ◽

Silicon Surface ◽

Ablation Threshold ◽

Water Environment ◽

Force Microscopy ◽

Atomic Force ◽

Minimum Depth

AbstractSilicon surface morphology induced by a femtosecond laser pulse at near-threshold fluences in water environment is investigated by means of atomic-force microscopy (AFM). With increasing fluence, the silicon surface transforms into nanoscale ring-shaped and blister structures, as well as smooth and nanostructured microcraters with a minimum depth of 1 nm. The formation of starlike patterns imprinted at the surface of microcraters at fluences above the ablation threshold is observed.

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Machining millimeter-scale deep holes in SiCf/SiC material using femtosecond laser filamentation effect

Materials Science Advanced Composite Materials ◽

10.18063/msacm.v2i1.748 ◽

2018 ◽

Vol 2 (3) ◽

Author(s):

Jie Zhao 1,2 ◽

Wenjun Wang 1,2 ◽

Ruijia Wang 1,2 ◽

Jianlei Cui 1,2

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Femtosecond Laser ◽

Surface Morphology ◽

Peak Power ◽

Processing Time ◽

Ablation Threshold ◽

Focus Position ◽

Laser Focus ◽

Scanning Electron

A 3.5 mm thick SiCf/SiC material was drilled in air environment using a femtosecond laser filament effect. The surface morphology of deep micropores was observed by scanning electron microscopy and the depth and profile of the pores were observed using μm-CT. The variation of entrance diameter, exit diameter and depth variation with laser focus position and processing time was further analyzed. The results showed that as the processing time of femtosecond laser increases, the ablation threshold of the material reached saturation. The exit and entrance diameter also stopped increasing and the aperture tend to saturate. The focus entered the interior of the material, allowing the location of the peak power near the surface of the material. So the entrance aperture was of good quality and the exit aperture was round.

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A Rapid Computational Method for Reducing the Search Space Required in Nuclear Reactor Optimization

Volume 11: New Developments in Simulation Methods and Software for Engineering Applications; Safety Engineering, Risk Analysis and Reliability Methods; Transportation Systems ◽

10.1115/imece2010-40244 ◽

2010 ◽

Author(s):

Andrew G. Osborne ◽

Mark R. Deinert

Keyword(s):

Nuclear Reactor ◽

Search Space ◽

Computational Method ◽

High Fidelity ◽

Reactor Physics ◽

Dimensional Parameter ◽

Fuel Cycles ◽

Reactor Optimization ◽

Fuel Pin ◽

Physics Model

Reactor optimization is central to increasing the efficiency of nuclear fuel cycles and critical for making meaningful comparisons between different design options. Optimization algorithms work by generating trial parameter sets which can be used as inputs to reactor physics models. Unfortunately, many reactor physics codes require substantial CPU time, making optimization of large parameter sets impractical. We have developed a method for finding optima within an N-dimensional parameter space using a fast, flexible reactor physics model that is capable of performing fuel burnup calculations on the order of once per second. Global optima found in this way can then be verified using a high fidelity reactor physics code. We demonstrate our approach by considering a simple fuel pin pitch optimization for a light-water reactor, and we find our code executes in 5 minutes. Repeating this approach using a high-fidelity Monte Carlo simulation requires approximately 15 days of runtime by contrast.

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