Abstract
Femtosecond pulsed laser (800 nm, 120 fs) micromachining of thin films of 3C-SiC (β-SiC) semiconductor deposited on silicon substrate was investigated as a function of pulse energy (0.5 μJ to 750 μJ). The purpose is to establish suitable laser parametric regime for the fabrication of high accuracy, high spatial resolution and thin diaphragms for high-temperature MEMS pressure sensor applications. Etch rate, ablation threshold and quality of micromachined features were evaluated. The governing ablation mechanisms, such as thermal vaporization, phase explosion, Coulomb explosion and photomechanical fragmentation, were correlated with the effects of pulse energy. The results show that the etch rate is higher and the ablation threshold is lower than those obtained with nanosecond pulsed excimer laser ablation, suggesting femtosecond laser’s potential for rapid manufacturing. In addition, the etch rates were substantially higher than those achievable in various reactive ion and electrochemical etching methods. Excellent quality of machined features with little collateral thermal damage was obtained in the pulse energy range (1–10 μJ). The leading material removal mechanisms under these conditions were photomechanical fragmentation, ultrafast melting and vaporization. At very low pulse energies (<1 μJ), nanoscale material removal has occurred with the formation of nanoparticles that is attributed to Coulomb explosion mechanism. The effect of assist gas on the process performance at low and high energy fluences is also presented.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
MRS Bulletin (1997) Silicon carbide electronic materials and devices. Vol. 22(3):19–56
Müller G, Krötz G, Niemann E (1994) SiC for sensors and high-temperature electronics. Sens Actuators A Phys 43(1–3):259–268, May
Okojie R, Ned A, Kurtz A (1997) Characteristics of a Hermetic 6H-SiC Pressure Sensor at 600C Tech. Dig. 1997. In: K. Wise, S. Senturia (eds) Int. Conf. Solid State Sensors and Actuators. Chicago IL, June 16–19, p.1407
Mehregany M, Zorman C (1999) SiC MEMS: opportunities and challenges for applications in harsh environments. Thin Solid Films 355–356:518–524, 1 November
Dong Y, Zorman C, Molian P (2003) Femtosecond pulsed laser micromachining of 3C-SiC structures based on a laser-induced defect-activation process. J Micromech Microeng 13(5):680–685
Chichkov B-N, Momma C, Nolte S, Alvensleben F, Tunnermann A (1996) Femtosecond, picosecond, and nanosecond laser ablation of solids. Appl Phys A 63(2):109–115
Ozono K, Obara M, Usui A, Sunakawa H (2001) High-speed ablation etching of GaN semiconductor using femtosecond laser. Opt Comm 189:103–106
Bonse J, Rudolph P, Kruger J, Baudach S, Kautek W (2000) Femtosecond pulse laser processing of TiN on silicon. Appl Sur Sci 154–155:659–663
Liu X, Du D, Mourou G (1997) Laser ablation and micromachining with ultra-short laser pulses. IEEE J Quant Electron 33(10):1706–1716
Ameer-Beg S, Perrie, W (1998) Femtosecond laser microstructuring of materials. Appl Surf Sci 127–129:875–880
Perrie W et al (2005) Femtosecond micro-structuring of alumina ceramic. Appl Surf Sci 258:213–217
Perrie W, Gilla M, Robinson B, Foxa P, O’Neil W (2004) Femtosecond laser micro-structuring of aluminum under helium. Appl Surf Sci 230:50–59
Robinson GM, Jackson MJ (2006) Femtosecond laser machining of aluminum surfaces under controlled gas atmospheres. J Mater Eng Perform 15(2):155–159
Sun J, Longtin JP (2001) Inert gas beam delivery for ultrafast laser micromachining at ambient pressure. Appl Surf Sci 89(12):8219–8223
Zoppel S, Farsari M, Merz R, Zehetner J, Stangl G, Reider G, Fotakis C (2006) Laser micro machining of 3C-SiC single crystals. Microelectron Eng 83:1400–1402
Toyoda K, Midorikawa K (2001) Micromachining of SiC by femtosecond ablation. Pacific Rim Conference on Lasers and Electro-Optics, CLEO - Technical Digest 2:II286–II287
Zorman C (2002) Deposition of 3C-SiC films on 100 mm diameter Si(100) wafers in large-volume LPCVD furnaces. Electrochem Solid-State Lett 5(10):G99
Zhang J, Sugioka K, Wada S, Tashiro H, Toyoda K (1997) Direct photoetching of single crystal SiC by VUV-266 nm multiwavelength laser ablation. Appl Phys A 64(4):367–371
Pearton S (2002) In: Zetterling C-M (ed) Process technology for silicon carbide devices, London, INSPEC, 2002 p 85
Gudde J, Hohlfeld J, Muller J, Matthias E (1998) Damage threshold dependence on electron-photon coupling in Au and Ni films. Appl Sur Sci 127–129:40–45
Bulgakova N, Burakov V, Meshcheryakov Y, Stoian R, Rosenfeld A, Hertel I (2007) Theoretical models and qualitative interpretations of fs-laser material processing. J Laser Micro/Nanoengineering 2(1):76
Von der Linde D, Schuler H (1996) Breakdown threshold and plasma formation in femtosecond laser-solid interactions. J Opt Soc Am B 13:216–222
Alexander, QW, Ihtesham HC, Xianfan X (2006) Plasma formation in fused silica induced by loosely focused femtosecond laser pulse. Appl Phys Lett 88(11):111502
Auguste T et al (1992) Defocusing effects of a picosecond terawatt laser pulse in an under dense plasma. Opt Commun 89:145–148
Rae SC (1993) Ionization-induced defocusing of intense laser pulses in high-pressure gases. Opt Commun 97:25–28
Gibbon P (2005) Short Pulse Laser Interactions with Matter: An Introduction. Imperial College Press
Perez D, Lewis L (2002) Ablation of solids under femtosecond laser pulses. Phys Rev Lett 89(25):25504
Shank C, Yen R, Hirlimann C (1983) Femtosecond-time-resolved surface structural dynamics of optically excited silicon. Phys Rev Lett 51(10):900–902
Rousse A, Rischel C, Fourmaux S, Uschmann I, Sebban S, Grillon G, Balcou P, Förster E, Geindre J, Audebert P, Gauthier J, Hulin D (2001) Non-thermal melting in semiconductors measured at femtosecond resolution. Nature 410:65–68
Stampfli P, Bennemann K (1994) Time dependence of laser-induced femtosecond lattice instability of Si and GaAs Role of longitudinal optical distortions. Phys Rev B 49(11):7299–7305
Kelly R, Miotello A (1997) On the mechanisms of target modification by ion beams and laser pulses. Nucl Instr Meth B 122:374–400
Bulgakova N, Bourakov I (2002) Phase explosion under ultra-short pulsed laser ablation: modeling with analysis of metastable state of melt. Appl Surf Sci 197–198:40–45
Sokolowski-Tinten K, Bialkowski J, Cavalleri A, von der Linde D, Oparin A, Meyer-ter-Vehn J, Anisimov S (1998) Transient states of matter during short pulse laser ablation. Phys Rev Lett 81(1):224–227
Lorazo P, Lewis L, Meunier M (2006) Thermodynamic pathways to melting, ablation, and solidification in absorbing solids under pulsed irradiation. Phys Rev B 73:134108
Miotello A, Kelly R (1999) Laser-induced phase explosion: new physical problems when a condensed phase approaches the thermodynamically critical temperature. Appl Phys A Suppl 69:S67
Stoian R, Ashkenasi D, Rosenfeld A, Campbell E (2000) Coulomb explosion in ultrashort pulsed laser ablation of Al203. Phys Rev B 62(19):13167–13172
Henyk M, Costache F, Reif J (2002) Femtosecond laser ablation from sodium chloride and barium flouride. Appl Surf Sci 186:381
Tamura H, Kohama T, Kondo K, Yoshida M (2001) Femtosecond-laser-induced spallation in aluminum. J Appl Phys 89(6):3520–3522
Nakata Y, Okada T, Maeda M (2003) Nano-size hollow bump array generated by single femtosecond laser pulse. Jpn J Appl Phys 42(12A):L1452–L1454
Korte F, Koch J, Chichkov B (2004) Formation of microbumps and nanojets on gold targets by femtosecond pulses. Applied Physics A 79(4–6):879–881
Meshcheryakov Y, Bulgakova N (2006) Thermoelastic modeling of microbump and nanojet formation on nanosize gold films under femtosecond laser irradiation. Appl Phys A 82(2):363–368
Eliezer S, Eliaz N, Grossman E, Fischer D, Gouzman I, Henis Z, Pecker S, Horovitz Y, Fraenkel M, Maman S, Lereah Y (2004) Synthesis of nanoparticles with femtosecond pulses. Physical Review B 69:144119
Bulgakova N, Bulgakov A (2001) Pulsed laser ablation of solids: transition from normal vaporization to phase explosion. Appl Phys A 73:199–208
von der Linde D, Sokolowski-Tinten K (2000) The physical mechanisms of short-pulse laser ablation. Appl Surf Sci 154–155:1–10
Song K, Xu X (1998) Explosive phase transformation in excimer laser ablation. Applied Surface Science 127–129:111–116
Henyk M, Wolfframm D, Reif J (2000) Ultra short pulse induced charged particle emission from wide bandgap crystals. Appl Surf Sci 168:263–266
Cheng H, Gillaspy J (1997) Nanoscale modification of silicon surfaces via Coulomb explosion. Phys Rev B 55:2628
Stoian R, Rosenfeld A, Ashkenasi D, Hertel I, Bulgakova N, Campbell E (2002) Surface charging and impulsive ion ejection during ultrashort pulsed laser ablation. Phys Rev Lett 88:97603
Roeterdink W, Juurlimk L, Vaughan O, Dura Diez J, Bonn M, Kleyn A (2003) Coulomb explosion in femtosecond laser ablation of Si(111). Appl Phys Lett 82(23):4190–4192
Schneider D, Briere M (1996) Investigations of interactions of highest charge state ions with surfaces. Phys Scr 53(2):228–242
Itabashi N et al (1995) Desorption of Ga and As atoms from GaAs surface induced by slow multiply charged Ar ions. Jpn J Appl Phys Part 1 34:6861–6865
Herrmann R, Gerlach J, Campbell E (1997) Molecular dynamics of laser ablation of silicon. Nucl Instrum Methods Phys Res B 122:401–404
Herrmann R, Gerlach J, Campbell E (1998) Ultrashort laser ablation of silicon: an MD simulation study. Applied Physics A 66(1):35–42
Ozkan A, Malshe A, Railkar T, Brown W, Shirk M, Molian P (1999) Femtosecond laser-induced periodic structure writing on diamond crystals and microclusters. Appl Phys Lett 75(23):3716–3718
Borowiec A, Haugen H (2003) Sub-wavelength ripple formation on the surfaces of compound semiconductors irradiated with femtosecond pulses. Appl Phys Lett 82(25):4462–4464
Yasumaru A, Miyazaki K, Kiuchi J (2003) Femtosecond-laser-indcued nanostructure on hard thin films of TiN and DLC. Appl Phys A 76(6):983–985
Pedraza A, Fowlkes J, Guan Y (2003) Surface nanostructuring of silicon. Appl Phys A 77(2):277–284
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Pecholt, B., Vendan, M., Dong, Y. et al. Ultrafast laser micromachining of 3C-SiC thin films for MEMS device fabrication. Int J Adv Manuf Technol 39, 239–250 (2008). https://doi.org/10.1007/s00170-007-1223-5
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00170-007-1223-5