Cavitation and spallation in liquid metal droplets produced by subpicosecond pulsed laser radiation

Krivokorytov, M. S.; Vinokhodov, A Yu; Sidelnikov, Yu. V.; Krivtsun, V. M.; Компанец, В. О.; Lash, A. A.; Koshelev, K. N.; Медведев, В. В.

doi:10.1103/physreve.95.031101

Cited by 34 publications

(45 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Intense, short-pulse laser radiation can produce strong shock waves in liquids leading in some spectacular cases to explosive cavitation and violent spallation of the material [1][2][3][4][5]. Such dramatic physical phenomena can readily find application, a very recent example of which is found in the field of nanolithography where microdroplets of liquid tin are used to create extreme ultraviolet (EUV) light [6][7][8].…”

Section: Introductionmentioning

confidence: 99%

Expansion Dynamics after Laser-Induced Cavitation in Liquid Tin Microdroplets

et al. 2018

View full text Add to dashboard Cite

The cavitation-driven expansion dynamics of liquid tin microdroplets is investigated, set in motion by the ablative impact of a 15-ps laser pulse. We combine high-resolution stroboscopic shadowgraphy with an intuitive fluid dynamic model that includes the onset of fragmentation, and find good agreement between model and experimental data for two different droplet sizes over a wide range of laser pulse energies. The dependence of the initial expansion velocity on these experimental parameters is heuristically captured in a single power law. Further, the obtained late-time mass distributions are shown to be governed by a single parameter. These studies are performed under conditions relevant for plasma light sources for extreme-ultraviolet nanolithography.

show abstract

Section: Introductionmentioning

confidence: 99%

Expansion Dynamics after Laser-Induced Cavitation in Liquid Tin Microdroplets

et al. 2018

View full text Add to dashboard Cite

show abstract

“…The physical process related to laser irradiation of droplets has been recently studied in detail. 2,3 The basic architecture of the present LPP sources has been well-described in many research papers. [8][9][10] The latest achievement of a CE of 6% was reported, and a 375-W inburst EUV power at low duty cycle was demonstrated on test sources in the development laboratories.…”

Section: Scaling Of Lpp Euv Source Toward Kw Average Powermentioning

confidence: 99%

“…The thin disc was pumped with a 2.2-kW continuous wave (CW), 969-nm fiber-coupled diode laser on a pump spot with a diameter of 5.2 mm. The disc was located in a compact 6.5-m long ring cavity with two V-passes through the disc per one roundtrip, and the footprint area of the amplifier is only 100 × 60 cm 2 . double Pockels cell with two 10 × 10 × 25 mm 3 BBO crystals in in-house developed holders was operated with a 10-kV voltage and repetition rate of <1 MHz.…”

Section: Laser Assistance In Euv Fel Source Technologymentioning

confidence: 99%

“…11,12 Recent work presents measurements and theoretical analysis of the deformation and fragmentation of spherical liquid-metal droplets by ps laser pulses. 2,3 60-μm droplets of Sn-In (tin-indium) alloy were irradiated by Ti:Sa laser pulses with a peak energy fluence of ∼100 J cm −2 . The observed evolution of the droplet shape was shown to confirm the previously reported experiment with ns and ps pulses.…”

Section: Scaling Of Lpp Euv Source Toward Kw Average Powermentioning

confidence: 99%

“…The background physics of this phenomenon is under intensive physical and experimental study. 2,3 The typical repetition rate of the droplet generation is 100 kHz, and a further increase is necessary to kW generation due to the limit of the maximum input main laser pulse energy to keep the CE at 6% level. The requirements for the prepulse laser are relatively critical: a few mJ, good beam quality, a few ps, high pointing accuracy, and pulse-to pulse energy stability at 100-kHz repetition rate.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

kW-class picosecond thin-disc prepulse laser Perla for efficient EUV generation

Endo

Smrž

Mužík

et al. 2017

J. Micro/Nanolith. MEMS MOEMS

View full text Add to dashboard Cite

, "kW-class picosecond thin-disc prepulse laser Perla for efficient EUV generation," J. Micro/Nanolith. MEMS MOEMS 16(4), 041011 (2017), doi: 10.1117/1.JMM.16.4.041011. Abstract. The technology for extreme ultraviolet (EUV) lithography sources is maturing. Laser produced plasma (LPP) sources with usable power >100 W have been used in high-volume manufacturing (HVM) applications, and 250-W sources are expected to be introduced in HVM soon. However, a further increase of power and cleanness may benefit a powerful picosecond (ps) laser in the near-infrared and wavelength converted spectral region. The HiLASE Centre has been working in thin-disc laser technology and has demonstrated a 0.5-kW platform Perla-C based on a very compact Yb:YAG regenerative amplifier. 100-kHz ps operation has been achieved with a fundamental spatial mode and excellent long-term pointing and energy stability. It is reported on a thin-disc-based ps Yb:YAG solid-state laser technology platform Perla developed in the Czech Republic and the present performance of delivering >4 mJ, <2-ps pulses at a 100-kHz repetition rate with the potential to be upgraded to 1 kW of average power and 1-MHz pulse repetition rate. The ps laser extendibility is important for kW-class LPP sources and controlled free electron laser EUV sources in 10-kW power region. © The Authors.Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI. IntroductionExtreme ultraviolet (EUV) lithography is taking off from a long technology development phase to high-volume manufacturing (HVM) in major semiconductor companies. Laser produced plasma (LPP) is the selected method for the required 13.5-nm source for its advantages of scalable output power, narrow spectrum, small source size, and cleanness. The source technology is already fairly advanced in each component level for a 250-W power supply. The next step for extension to the finer line width as a 3-nm node and beyond is based on a high NA imaging system, which requires a further increase of EUV source power to the kW level. A conceptual study based on the present LPP technology on a possible path to the realization of a kW 13.5-nm tin EUV source was reported. 1 There are several key technologies in the LPP source for high average power, and conditioning of the injected micro tin droplet into the mist target is critical for realizing higher conversion efficiency (CE) of up to 6% and full ionization for efficient exhaust in a magnetic field. It was experimentally demonstrated that the resulting mist shape is dependent on the initial laser pulses, and a picosecond (ps) laser can produce a lower density mist distribution rather than nanosecond (ns) pulses. The background physics of this phenomenon is under intensive physical and experimental study.2,3 The typical repetition rate of the droplet generation is 100 kHz, and a further increase is necessary to kW generation due to t...

show abstract

Cylindrically and non-cylindrically symmetric expansion dynamics of tin microdroplets after ultrashort laser pulse impact

et al. 2021

View full text Add to dashboard Cite

In this work, the expansion dynamics of liquid tin micro-droplets irradiated by femtosecond laser pulses were investigated. The effects of laser pulse duration, energy, and polarization on ablation, cavitation, and spallation dynamics were studied using laser pulse durations ranging from 220 fs to 10 ps, with energies ranging from 1 to 5 mJ, for micro-droplets with an initial radius of 15 and 23 $$\upmu$$ μ m. Using linearly polarized laser pulses, cylindrically asymmetric shock waves were produced, leading to novel non-symmetric target shapes, the asymmetry of which was studied as a function of laser pulse parameters and droplet size. A good qualitative agreement was obtained between smoothed-particle hydrodynamics simulations and high-resolution stroboscopic experimental data of the droplet deformation dynamics.

show abstract

Cavitation and spallation in liquid metal droplets produced by subpicosecond pulsed laser radiation

Cited by 34 publications

References 35 publications

Expansion Dynamics after Laser-Induced Cavitation in Liquid Tin Microdroplets

Expansion Dynamics after Laser-Induced Cavitation in Liquid Tin Microdroplets

kW-class picosecond thin-disc prepulse laser Perla for efficient EUV generation

Cylindrically and non-cylindrically symmetric expansion dynamics of tin microdroplets after ultrashort laser pulse impact

Contact Info

Product

Resources

About