Micromachining using the high energy flat-top beam of a femtosecond pulse UV laser system: micropillar prefabrication

• DOI: 10.1007/s00339-023-06679-x
• Publication Date: 2023-05-11T01:21:44Z
• Authors: Péter Imre Szabó; Dávid Ugi; Barnabás Gilicze; Zoltán Dankházi; Sándor Lipcsei; Zsolt Homik; Zsolt Tóth
• Keywords: Laser Ablation

Abstract Ablation with ultrashort laser pulses as a surface micromachining tool was studied using hybrid die-excimer system that has high energy per pulse (tens of mJ’s), about 600 fs duration and low repetition rate (2 Hz). The effect ablation on the material microstructure this pulsed studied. Micropillars were fabricated by spot size hundreds micrometers. Two methods tested for micromachining. Multiple standing sample resulted in columnar microscturcure around micropillars. This unwanted structure avoided beam scanning, resulting rather homogeneous ditch. By HR-EBSD measurement it found heat affected zone is less than 1 $$\mu \textrm{m}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>μ</mml:mi> <mml:mtext>m</mml:mtext> </mml:mrow> </mml:math> , which confirmed numerical temperature simulations, too. dislocation density measured below specimen unaltered, meaning no significant crystal degradation occurred. In summary, large-scale micro objects diameter order $$100~\mu <mml:mn>100</mml:mn> <mml:mspace /> without change crystalline surface, like micropillars compression tests, can be fabricated.