Abstract
We report experimental results of three-dimensional (3D) modification inside intrinsic and doped silicon wafers using laser pulses with 1.55 µm wavelength and 3.5 ns pulse duration. Permanent modification in the form of lines is generated inside silicon by tightly focusing and continuously scanning the laser beam inside samples, without introducing surface damage. Cross sections of these lines are observed after cleaving the samples and are further analyzed after mechanical polishing followed by chemical etching. With the objective lens corrected for spherical aberration, tight focusing inside silicon is achieved and the optimal focal depth is identified. The laser-induced modification has triangular shape and appears in regions prior to the geometrical focus, indicating significant absorption in those regions. Experiments with doped samples show similar modification for doping concentrations (and corresponding initial free carrier densities) in the range of 1013–1016 cm−3. At carrier densities of 1018 cm−3, linear absorption of light becomes significant and the modification is reduced in size.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
R. Gattass, E. Mazur, Femtosecond laser micromachining in transparent materials. Nat. Photonics 2, 219–225 (2008)
K.M. Davis, K. Miura, N. Sugimoto, K. Hirao, Writing waveguides in glass with a femtosecond laser. Opt. Lett. 21, 1729–1731 (1996)
K. Sugioka, Y. Hanada, K. Midorikawa, Three-dimensional femtosecond laser micromachining of photosensitive glass for biomicrochips. Laser Photonics Rev. 4, 386–400 (2010)
Y. Liao, J. Song, E. Li, Y. Luo, Y. Shen, D. Chen et al., Rapid prototyping of three-dimensional microfluidic mixers in glass by femtosecond laser direct writing. Lab Chip 12, 746–749 (2012)
J. Xu, Y. Liao, H. Zeng, Z. Zhou, H. Sun, J. Song et al., Selective metallization on insulator surfaces with femtosecond laser pulses. Opt. Express 15, 12743–12748 (2007)
R. Osellame, H.J.W.M. Hoekstra, G. Cerullo, M. Pollnau, Femtosecond laser microstructuring: an enabling tool for optofluidic lab-on-chips. Laser Photonics Rev. 5, 442–463 (2011)
E.G. Gamaly, A.V. Rode, Physics of ultra-short laser interaction with matter: from phonon excitation to ultimate transformations. Prog. Quantum Electron. 37, 215–323 (2013)
P. Balling, J. Schou, Femtosecond-laser ablation dynamics of dielectrics: basics and applications for thin films. Rep. Prog. Phys. 76, 036502 (2013)
X. Yu, Q. Bian, B. Zhao, Z. Chang, P.B. Corkum, S. Lei, Near-infrared femtosecond laser machining initiated by ultraviolet multiphoton ionization. Appl. Phys. Lett. 102, 101111 (2013)
E.G. Gamaly, S. Juodkazis, K. Nishimura, H. Misawa, B. Luther, Davies, laser-matter interaction in the bulk of a transparent solid: confined microexplosion and void formation. Phys. Rev. B 73, 214101 (2006)
Y. Liao, Y. Shen, L. Qiao, D. Chen, Y. Cheng, K. Sugioka et al., Femtosecond laser nanostructuring in porous glass with sub-50 nm feature sizes. Opt. Lett. 38, 187–189 (2013)
P.C. Verburg, G.R.B.E. Römer, A.J. Huis in 't Veld, Two-photon–induced internal modification of silicon by erbium-doped fiber laser. Opt. Express 22, 21958–21971 (2014)
M. Mori, Y. Shimotsuma, T. Sei, M. Sakakura, K. Miura, H. Udono, Tailoring thermoelectric properties of nanostructured crystal silicon fabricated by infrared femtosecond laser direct writing. Phys. Status Solidi 7, 1–7 (2015)
Y. Ito, H. Sakashita, R. Suzuki, M. Uewada, K.P. Luong, R. Tanabe, Modification and machining on back surface of a silicon substrate by femtosecond laser pulses at 1552 nm. J. Laser Micro Nanoeng. 9, 98–102 (2014)
D. Grojo, A. Mouskeftaras, P. Delaporte, S. Lei, Limitations to laser machining of silicon using femtosecond micro-Bessel beams in the infrared. J. Appl. Phys. 117, 153105 (2015)
M.J. Nasse, J.C. Woehl, Realistic modeling of the illumination point spread function in confocal scanning optical microscopy. J. Opt. Soc. Am. A 27, 295–302 (2010)
X. Yu, Y. Liao, F. He, B. Zeng, Y. Cheng, Z. Xu et al., Tuning etch selectivity of fused silica irradiated by femtosecond laser pulses by controlling polarization of the writing pulses. J. Appl. Phys. 109, 053114 (2011)
S. Leyder, D. Grojo, P. Delaporte, W. Marine, M. Sentis, O. Utéza, Non-linear absorption of focused femtosecond laser pulses at 1.3 μm inside silicon: independence on doping concentration. Appl. Surf. Sci. 278, 13–18 (2013)
Acknowledgements
Finance support for the author C. T-H and laser support are provided by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, US Department of Energy (DOE) under Grant No. DE-FG02-86ER13491. Partial financial support for this work by the National Science Foundation under Grant No. CMMI-1537846 is also gratefully acknowledged.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Yu, X., Wang, X., Chanal, M. et al. Internal modification of intrinsic and doped silicon using infrared nanosecond laser. Appl. Phys. A 122, 1001 (2016). https://doi.org/10.1007/s00339-016-0540-7
Received:
Accepted:
Published:
DOI: https://doi.org/10.1007/s00339-016-0540-7