Experimental Investigations on Laser Ablation of Aluminum in Sub-Picosecond Regimes

• Published in: Applied sciences Vol. 10; no. 24; p. 8883
• Main Authors: Garasz, Katarzyna, Kocik, Marek
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.12.2020
• Subjects: Ablation; ablation threshold; Aluminum; Energy; Femtosecond pulsed lasers; femtosecond pulses; Heat; Irradiation; Laser ablation; Laser machining; Lasers; Mechanical systems; Metal foils; Microelectromechanical systems; Micromachining; micromachining of aluminum; Nozzles; precise micromachining; Pulse duration; sub-picosecond regime; Ultrafast lasers; Japan
• ISSN: 2076-3417; 2076-3417
• DOI: 10.3390/app10248883

Due to high power and ultrashort pulses, femtosecond lasers excel at (but are not limited to) processing materials whose thicknesses are less than 500 microns. Numerous experiments and theoretical analyses testify to the fact that there are solid grounds for the applications of ultrafast laser micromachining. However, with high costs and complexity of these devices, a sub-picosecond laser that might be an alternative when it comes to various micromachining applications, such as patterns and masks in thin metal foils, micro-nozzles, thermo-detectors, MEMS (micro electro-mechanical systems), sensors, etc. Furthermore, the investigation of sub-picosecond laser interactions with matter could provide more knowledge on the ablation mechanisms and experimental verification of existing models for ultrashort pulse regimes. In this article, we present the research on sub-picosecond laser interactions with thin aluminum foil under various laser pulse parameters. Research was conducted with two types of ultrafast lasers: a prototype sub-picosecond Yb:KYW laser (650 fs) and a commercially available femtosecond Ti:S laser (35 fs). The results show how the variables such as pulse width, energy, frequency, wavelength and irradiation time affect the micromachining process.