Effect of surface roughness on femtosecond laser ablation of 4H-SiC substrates

Abstract

Ablation threshold is an important concept in the study of femtosecond laser micro- and nano-machining. In this paper, the ablation experiments of three kinds of surface roughness 4H-SiC substrates irradiated by femtosecond laser were carried out. The feature thresholds were systematically measured for three surface roughness SiC substrates and found in the modification and annealing regions ranging from coincidence (R_a=0.5 nm) to a clear demarcation (R_a=5.5 nm), eventually being difficult to identify the presence of the former (R_a=89 nm). Under multi-pulse laser irradiation, oriented ripple structures were generated in the annealing region, where deep subwavelength ripples (about 110 nm, Λ ≈ 0.2λ) can be generated above substrates with surface roughness higher than 5.5 nm. We investigated the effect of surface roughness on the ablation morphology, ablation threshold, and periodic structures of femtosecond laser ablation of 4H-SiC substrates, while the ablation threshold was tended to decrease and stabilize with the increase of pulse number N⩾500.

Keywords

4H-SiC / surface roughness / ablation threshold / periodic structure / femtosecond laser

References

[1] MorkoçH, StriteS, GaoG B, et al.. Large-band-gap SiC, III–V nitride, and II–VI ZnSe-based semiconductor device technologies [J]. Journal of Applied Physics, 1994, 76(3): 1363-1398

[2] PresserV, NickelK G. Silica on silicon carbide [J]. Critical Reviews in Solid State and Materials Sciences, 2008, 33(1): 1-99

[3] VorobyevA, GuoC. Direct femtosecond laser surface nano/microstructuring and its applications [J]. Laser & Photonics Reviews, 2013, 7(3): 385-407

[4] MalinauskasM, ŽukauskasA, HasegawaS, et al.. Ultrafast laser processing of materials: From science to industry [J]. Light: Science & Applications, 2016, 5(8): e16133

[5] ZhuZ, WuJ, WuZ, et al.. Femtosecond laser micro/nano fabrication for bioinspired superhydrophobic or underwater superoleophobic surfaces [J]. Journal of Central South University, 2021, 28123882-3906

[6] SugiokaK, ChengY. Ultrafast lasers—Reliable tools for advanced materials processing [J]. Light: Science & Applications, 2014, 3(4): e149

[7] YinK, WuZ, WuJ, et al.. Solar-driven thermal-wind synergistic effect on laser-textured superhydrophilic copper foam architectures for ultrahigh efficient vapor generation [J]. Applied Physics Letters, 2021, 11821211905

[8] WU Ting-ni, WU Zhi-peng, HE Yu-chun, et al. Femtosecond laser textured porous nanowire structured glass for enhanced thermal imaging [J]. Chinese Optics Letters, 2022(3): 153–156.

[9] BonseJ, KrügerJ, HöhmS, et al.. Femtosecond laser-induced periodic surface structures [J]. Journal of Laser Applications, 2012, 244042006

[10] GeminiL, HashidaM, ShimizuM, et al.. Periodic nanostructures self-formed on silicon and silicon carbide by femtosecond laser irradiation [J]. Applied Physics A, 2014, 117149-54

[11] HöhmS, RosenfeldA, KrügerJ, et al.. Femtosecond diffraction dynamics of laser-induced periodic surface structures on fused silica [J]. Applied Physics Letters, 2013, 102(5): 054102

[12] NathalaC S R, AjamiA, IoninA A, et al.. Experimental study of fs-laser induced sub-100-nm periodic surface structures on titanium [J]. Optics Express, 2015, 2355915-5929

[13] ZhangD, GökceB, SommerS, et al.. Debris-free rear-side picosecond laser ablation of thin germanium wafers in water with ethanol [J]. Applied Surface Science, 2016, 367: 222-230

[14] ChenH, JiaT, HuangM, et al.. Visible-infrared femtosecond laser-induced optical breakdown of 6H-SiC [J]. Acta Optica Sinica, 2006, 26(3): 467-470(in Chinese)

[15] BETTIS J, HOUSE I R, GUENTHER A. 5.1 spot size and pulse duration dependence of laser-induced damage [M]//Laser Induced Damage in Optical Materials, 1976.

[16] LiuX, DuD, MourouG. Laser ablation and micromachining with ultrashort laser pulses [J]. IEEE Journal of Quantum Electronics, 1997, 33(10): 1706-1716

[17] RudolphP, BrzezinkaK W, WäscheR, et al.. Physical chemistry of the femtosecond and nanosecond lasermaterial interaction with SiC and a SiC−TiC−TiB₂ composite ceramic compound [J]. Applied Surface Science, 2003, 208209: 285-291

[18] JeeY, BeckerM F, WalserR M. Laser-induced damage on single-crystal metal surfaces [J]. Journal of the Optical Society of America B, 1988, 5(3): 648

[19] EmmonyD C, HowsonR P, WillisL J. Laser mirror damage in germanium at 10.6 µm [J]. Applied Physics Letters, 1973, 2311598-600

[20] HuangM, ZhaoF, ChengY, et al.. Origin of laser-induced near-subwavelength ripples: Interference between surface plasmons and incident laser [J]. ACS Nano, 2009, 3(12): 4062-4070

[21] BonseJ, GräfS. Maxwell meets Marangoni—A review of theories on laser-induced periodic surface structures [J]. Laser & Photonics Reviews, 2020, 14(10): 2000215

[22] WuX J, JiaT Q, ZhaoF L, et al.. Formation mechanisms of uniform arrays of periodic nanoparticles and nanoripples on 6H-SiC crystal surface induced by femtosecond laser ablation [J]. Applied Physics A, 2007, 864491-495

[23] ReifJ, VarlamovaO, CostacheF. Femtosecond laser induced nanostructure formation: Self-organization control parameters [J]. Applied Physics A, 2008, 92(4): 1019-1024

[24] JiaoL, KongD, ZhangX, et al.. Ripple period adjustment on SiC surface based on electron dynamics control and its polarization anisotropy [J]. Applied Physics A, 2021, 127(1): 1-9

[25] PanA, DiasA, Gomez-AranzadiM, et al.. Formation of laser-induced periodic surface structures on niobium by femtosecond laser irradiation [J]. Journal of Applied Physics, 2014, 115(17): 173101

[26] ZhangR, HuangC, WangJ, et al.. Evolution of micro/nano-structural arrays on crystalline silicon carbide by femtosecond laser ablation [J]. Materials Science in Semiconductor Processing, 2021, 121: 105299

[27] ZhangD, SugiokaK. Hierarchical microstructures with high spatial frequency laser induced periodic surface structures possessing different orientations created by femtosecond laser ablation of silicon in liquids [J]. Opto-Electronic Advances, 2019, 2319000201-19000218

[28] ZhangD, RanjanB, TanakaT, et al.. Underwater persistent bubble-assisted femtosecond laser ablation for hierarchical micro/nanostructuring [J]. International Journal of Extreme Manufacturing, 2020, 2(1): 015001

[29] TomitaT, KinoshitaK, MatsuoS, et al.. Effect of surface roughening on femtosecond laser-induced ripple structures [J]. Applied Physics Letters, 2007, 9015153115

[30] TomitaT, KumaiR, MatsuoS, et al.. Cross-sectional morphological profiles of ripples on Si, SiC, and HOPG [J]. Applied Physics A, 2009, 972271-276

[31] TomitaT, OkadaT, KawaharaH, et al.. Microscopic analysis of carbon phases induced by femtosecond laser irradiation on single-crystal SiC [J]. Applied Physics A, 2010, 100(1): 113-117

[32] LenznerM, KrügerJ, SartaniaS, et al.. Femtosecond optical breakdown in dielectrics [J]. Physical Review Letters, 1998, 80(18): 4076-4079

[33] ZhaiZ, WangW, ZhaoJ, et al.. Influence of surface morphology on processing of C/SiC composites via femtosecond laser [J]. Composites Part A: Applied Science and Manufacturing, 2017, 102117-125

[34] SipeJ, YoungJ F, PrestonJ, et al.. Laser-induced periodic surface structure. I. Theory [J]. Physical Review B, 1983, 27(2): 1141

[35] FlorianC, KirnerS, KrügerJ, et al.. Surface functionalization by laser-induced periodic surface structures [J]. Journal of Laser Applications, 2020, 32022063

[36] SongJ, TaoW, GongM, et al.. The three-level ripples induced by femtosecond laser on a 6H-SiC single crystal and the formation mechanism [J]. Applied Physics A, 2016, 12241-7

[37] ObaraG, ShimizuH, EnamiT, et al.. Growth of high spatial frequency periodic ripple structures on SiC crystal surfaces irradiated with successive femtosecond laser pulses [J]. Optics Express, 2013, 21(22): 26323-26334

[38] RudenkoA, ColombierJ P, HöhmS, et al.. Spontaneous periodic ordering on the surface and in the bulk of dielectrics irradiated by ultrafast laser: A shared electromagnetic origin [J]. Scientific Reports, 2017, 712306