High precision laser direct microstructuring system based on bursts of picosecond pulses

Mur, Jaka (author), Petelin, Jaka (author), Osterman, Natan (author), Petkovšek, Rok (author)

We have developed an efficient, high precision system for direct laser microstructuring using fiber laser generated bursts of picosecond pulses. An opto-mechanical system for beam deflection and sample movement, precise pulse energy control, and a custom built fiber laser with the pulse duration of 65 ps have been combined in a compact setup. The setup allows structuring of single-micrometer sized objects with a nanometer resolution of the laser beam positioning due to a combination of acousto-optical laser beam deflection and tight focusing. The precise synchronization of the fiber laser with the pulse burst repetition frequency of up to 100 kHz allowed a wide range of working parameters, including a tuneable number of pulses in each burst with the intra-burst repetition frequency of 40 MHz and delivering exactly one burst of pulses to every chosen position. We have demonstrated that bursts of pulses significantly increase the ablation efficiency during the microstructuring of a copper layer and shorten the typical processing time compared to the single pulse per spot regime. We have used a simple short-pulse ablation model to describe our single pulse ablation data and modified the model to describe the ablation with bursts. Bursts of pulses also contribute to a high quality definition of structure edges and sides. The increased ablation efficiency at lower pulse energies compared to the single pulse per spot regime opens a window to utilize compact fiber lasers designed to operate at lower pulse energies, reducing the overall system complexity and size.

• Language: English
• Keywords: light-matter interaction, laser processing, direct laser microstructuring, bursts of pulses, fiber lasers, picosecond pulses
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Author Accepted Manuscript
• Year: 2017
• Number of pages: f. 1-7
• Numbering: Vol. 50
• PID: 20.500.12556/RUL-105550
• UDC: 535.374:620.3(045)
• ISSN on article: 0022-3727
• DOI: 10.1088/1361-6463/aa7b5a
• COBISS.SI-ID: 15571227
• Publication date in RUL: 05.12.2018

Record is a part of a journal

• Title: Journal of physics
• Shortened title: J. phys., D, Appl. phys.
• Publisher: Institute of Physics
• ISSN: 0022-3727
• COBISS.SI-ID: 1011215

Secondary language

• Language: Slovenian
• Keywords: interakcija svetloba-snov, laserska obdelava, direktno lasersko mikrostrukturiranje, paketi pulzov, vlakenski laserji, pikosekundni pulzi

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: L2-6780, P2-0270, P2-0392
• Name: Hibridni ps laser velikih moči, Proizvodni sistemi, laserske tehnologije in spajanje materialov, Optodinamika