Modeling of Process Mechanisms in Pulsed Laser Micro Machining on Lithium Niobate Substrates
Teppei Onuki, Ippei Murayama, Hirotaka Ojima,
Jun Shimizu, and Libo Zhou
Ibaraki University, 4-12-1 Nakanarusawa, Hitachi, Ibaraki 316-8511, Japan
The mechanism behind the laser ablation of LN is investigated using near infrared pico-second-pulsed laser. A model of the mechanism is developed, deriving the mechanical, thermal, and photonic properties of LN in addition to doing preliminary experiments on laser ablation with controlled laser fluence. β is material removal using the nonthermal process via multiphoton ionization, γ is nonthermal material removal with chipping or cracking produced by generated heat (but at temperatures below the melting point), and δ is material removal using the thermal process with temperatures above the melting point, resulting in resolidification at the surface and the adhesion of oncemolten burrs around the processed area. In a process modes map constructed through exhaustive experiments on laser ablation under various irradiation conditions (at specific energy ρ and with number of pulse shots N’), different contributions of ρ and N’ in the machining process are found. In terms of machining quality, desirable conditions in the control of laser irradiations are the use of weaker ρ and increased N’ to keep thermal damage to a minimum and to raise the removal rate.
Jun Shimizu, and Libo Zhou, “Modeling of Process Mechanisms in Pulsed Laser Micro Machining on Lithium Niobate Substrates,” Int. J. Automation Technol., Vol.8, No.6, pp. 896-902, 2014.
-  T. Sano, T. Onuki, Y. Hamate, M. Hojo, S. Nagasawa, and H. Kuwano, “Micro blender and separator using inner-vortex of droplet induced by surface acoustic wave,” IEEE Proc. of Transducers2009, pp. 370-373, 2009.
-  M. Miyashita, T. Onuki, S. Nagasawa, and H. Kuwano, “A surface acoustic wave dynamics control device by grating structure,” IEEE Proc. of MEMS2008, pp. 661-664, 2008.
-  J. Meijer D. Deshpande, E. Stach, K. Rajukar, and D. Alexander, “Investigation of Femtosecond Laser-assistedMicromachining of Lithium Niobate,” CIRP Annals-Manufacturing Technology, Vol.51, Issue 2, pp. 531-550, 2002.
-  Y. Di Maio, J. P. Colombier, P. Cazottes, and E. Audourd, “Ultrafast laser ablation characteristics of PZT ceramic: Analysis methods and comparison with metals,” Optics and Lasers in Engineering, Vol.50, pp. 1582-1591, 2012.
-  T. Nakamoto, N. Shirakawa, K. Kishida, K. Tanaka, and H. Inui, “Synthesis of Porous Titanium with Directional Pores by Selective Laser Melting,” Int. J. of Automation Technology, Vol.6, No.5, pp. 597-603, 2012.
-  G. Zhou and M. Gu, “Direct optical fabrication of threedimensional photonic crystals in a high refractive index LiNbO3 crystal,” Opt. Lett., Vol.31, 2783, 2006.
-  A. Malshe, D. Deshpande, E. Stach, K. Rajukar, and D. Alexander, “Investigation of Femtosecond Laser-assisted Micromachining of Lithium Niobate,” CIRP Annals-Manufacturing Technology, Vol.53, Issue 1, pp. 187-190, 2004.
-  J. Burghoff, C. Grebing, S. Nolte, and A. Tünnermann, “Waveguides in lithium niobate fabricated by focused ultrashort laser pulses,” Applied Surface Science, Vol.253, pp. 7899-7902, 2007.
-  J. A. Chaos, R. W. Dreyfus, A. Perea, R. Serna, J. Gonzalo, and C. N. Afonso, “Delayed release of Li atoms from laser ablated lithium niobate,” Appl. Phys. Lett., Vol.76, 649, 2000.
-  R. A. Ganeev, L. A. Kulagin, A. I. Ryasnyansky, R. I. Tugushev, and T. Usmanov, “Characterization of nonlinear optical parameters of KDP, LiNbO3 and BBO crystals,” Optics Communications, Vol.229, pp. 403-412, 2004.
-  W-C. Yang, B. J. Rodriguez, A. Gruverman, and R. J. Nemanich, “Polarization-dependent electron affinity of LiNbO3 surfaces,” Appl. Phys. Lett., Vol.85, pp. 2316-2318, 2004.
-  O. Beyer, D. Maxein, K. Buse, B. Sturman, H. T. Hsieh, and D. Psaltis, “Investigation of nonlinear absorption processes with femtosecond light pulses in lithium niobate crystals,” Phys. Rev. E, Vol.71, 056603-(1-8), 2005.
-  Y. Nakagawa, K. Yamanouchi, and K. Shibayama, “Third-order elastic constants of lithium niobate,” J. Appl. Phys., 48, pp. 3969-3974, 1966.