Abstract
The ablation of copper, using a 10 GHz burst ultrafast laser with a wavelength of 1030 nm, a pulse duration of 1 ps, a variable total laser fluence, and a number of sub-pulses per burst, is investigated theoretically. A two-temperature model with an extended Lorentz–Drude model for dynamic optical properties is used to simulate the melting and ablation process. Due to the heat accumulation from the preceding pulses, multipulse laser ablation could be advantageous over a single pulse. Moreover, the ablation performance can be maximized by properly selecting the pulse number, separation time, and energy in a laser burst. The numerical result shows that the present prediction is in fairly agreement with existing experimental result. Under the same total laser fluence of 32 J/cm2, a 10 GHz burst laser with an optimized 128 sub-pulse can significantly enhance the ablation depth, 4.2 times that a single pulse does. It is found that the optimized ablation depth is a linear function of the total fluence of ultrafast laser bursts.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
R.R. Gattass, E. Mazur, Femtosecond laser micromachining in transparent materials. Nat. Photonics 2, 219–225 (2008)
S. Nolte, C. Momma, H. Jacobs, A. Tunnermann, B.N. Chichkov, B. Wellegehausen, H. Welling, Ablation of metals by ultrashort laser pulses. J Opt Soc Am B Opt Phys 14, 2716–2722 (1997)
K.-H. Leitz, B. Redlingshöfer, Y. Reg, A. Otto, M. Schmidt, Metal Ablation with short and ultrashort laser pulses. Phys. Proc. 12, 230–238 (2011)
C.W. Cheng, S.Y. Wang, K.P. Chang, J.K. Chen, Femtosecond laser ablation of copper at high laser fluence: Modeling and experimental comparison. Appl. Surf. Sci. 361, 41–48 (2016)
A. Ancona, S. Döring, C. Jauregui, F. Röser, J. Limpert, S. Nolte, A.J.O.L. Tünnermann, Femtosecond and picosecond laser drilling of metals at high repetition rates and average powers. Opt. Lett. 34, 3304–3306 (2009)
C. Kerse, H. Kalaycıoğlu, P. Elahi, B. Çetin, D.K. Kesim, Ö. Akçaalan, S. Yavaş, M.D. Aşık, B. Öktem, H. Hoogland, R. Holzwarth, F.Ö. Ilday, Ablation-cooled material removal with ultrafast bursts of pulses. Nature 537, 84–88 (2016)
G. Bonamis, K. Mishchick, E. Audouard, C. Hönninger, E. Mottay, J. Lopez, I. Manek-Hönninger, High efficiency femtosecond laser ablation with gigahertz level bursts. J. Laser Appl. 31, 022205 (2019)
Z. Lin, H. Matsumoto, J. Kleinert, Ultrafast laser ablation of copper with~ GHz bursts, in: Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XXIII, International Society for Optics and Photonics, pp. 1051902 (2018)
K. Mishchik, G. Bonamis, J. Qiao, J. Lopez, E. Audouard, E. Mottay, C. Hönninger, I.J.O.L. Manek-Hönninger, High-efficiency femtosecond ablation of silicon with GHz repetition rate laser source. Opt. Lett. 44, 2193–2196 (2019)
Y. Ren, C.W. Cheng, J.K. Chen, Y. Zhang, D.Y. Tzou, Thermal ablation of metal films by femtosecond laser bursts. Int. J. Therm. Sci. 70, 32–40 (2013)
J. Byskov-Nielsen, J.-M. Savolainen, M.S. Christensen, P. Balling, Ultra-short pulse laser ablation of copper, silver and tungsten: experimental data and two-temperature model simulations. Appl. Phys. A Mater. Sci. Process. 103, 447–453 (2011)
Y.P. Ren, J.K. Chen, Y.W. Zhang, J. Huang, Ultrashort laser pulse energy deposition in metal films with phase changes. Appl. Phys. Lett. 98, 191105 (2011)
G.D. Tsibidis, The influence of dynamical change of optical properties on the thermomechanical response and damage threshold of noble metals under femtosecond laser irradiation. J. Appl. Phys. 123, 085903 (2018)
P.T. Mannion, J. Magee, E. Coyne, G.M. O'Connor, T.J. Glynn, The effect of damage accumulation behaviour on ablation thresholds and damage morphology in ultrafast laser micro-machining of common metals in air. Appl. Surf. Sci. 233, 275–287 (2004)
R. Kelly, A. Miotello, Comments on explosive mechanisms of laser sputtering. Appl. Surf. Sci. 96–98, 205–215 (1996)
T. Hirsiger, M. Gafner, S. Remund, M.V. Chaja, A. Urniezius, S. Butkus, B. Neuenschwander, Machining metals and silicon with GHz bursts: Surprising tremendous reduction of the specific removal rate for surface texturing applications, in: Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XXV, International Society for Optics and Photonics, pp. 112670T (2020)
G. Bonamis, K. Mishchik, J. Lopez, I. Manek-Hönninger, E. Audouard, C. Honninger, E. Mottay, Industrial GHz femtosecond laser source for high efficiency ablation, in: CLEO: Applications and Technology, Optical Society of America, pp. AM2M.4 (2018)
Acknowledgements
This work was supported by the Ministry of Science and Technology of Republic of China, under Contract MOST 107-2221-E-009-061-MY3.
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Cheng, CW., Chen, JK. Ultrafast laser ablation of copper by GHz bursts. Appl. Phys. A 126, 649 (2020). https://doi.org/10.1007/s00339-020-03853-3
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s00339-020-03853-3