caa a22 4500 463213750 CHVBK 20180405153149.0 cr unu---uuuuu 170326e20071101xx s 000 0 eng 10.1007/s00339-007-4132-4 doi (NATIONALLICENCE)springer-10.1007/s00339-007-4132-4 Influence of substrate cooling on femtosecond laser machined hole depth and diameter [Elektronische Daten] [H.Y. Zheng, Y.C. Lam, C. Sundarraman, D.V. Tran] Substrate temperature was observed to affect the machined hole depth and diameter during Ti:sapphire femtosecond laser machining of a copper substrate. We studied the blind holes drilled on copper specimens by multiple femtosecond laser (fs) pulses under two temperature conditions, namely the liquid nitrogen temperature (∼77K) and the atmospheric temperature (∼298K). Compared to the atmospheric temperature condition, we found that the diameters of the holes are smaller and the depths of the holes are deeper under the liquid nitrogen temperature condition. We attribute the reduction in diameter to the faster heat dissipation of the cooler substrate. We calculated multiple beam reflections in a channel and attribute the increased depth of the cooler substrate to the enhanced multiple laser beam reflections inside the laser drilled hole. Springer-Verlag, 2007 Zheng H.Y. The University of New South Wales Asia, 1 Kay Siang Road, 248922, Singapore, Singapore aut Lam Y.C. School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore, Singapore aut Sundarraman C. School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore, Singapore aut Tran D.V. School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore, Singapore aut Applied Physics A Springer-Verlag 89/2(2007-11-01), 559-563 0947-8396 89:2<559 2007 89 339 https://doi.org/10.1007/s00339-007-4132-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00339-007-4132-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Zheng H.Y. The University of New South Wales Asia, 1 Kay Siang Road, 248922, Singapore, Singapore aut NATIONALLICENCE 700 1- Lam Y.C. School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore, Singapore aut NATIONALLICENCE 700 1- Sundarraman C. School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore, Singapore aut NATIONALLICENCE 700 1- Tran D.V. School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore, Singapore aut NATIONALLICENCE 773 0- Applied Physics A Springer-Verlag 89/2(2007-11-01), 559-563 0947-8396 89:2<559 2007 89 339 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer