High brightness EUV sources based on laser plasma at using droplet liquid metal target

Journal Article · Tue May 31 00:00:00 EDT 2016 · Quantum Electronics (Woodbury, N.Y.)

DOI:https://doi.org/10.1070/QEL16019· OSTI ID:22724636

Vinokhodov, A Yu; Krivokorytov, M S ^[1]; Sidelnikov, Yu V; Krivtsun, V M; Medvedev, V V; Koshelev, K N ^[2]

---

1. EUV Labs, Ltd., Troitsk, Moscow (Russian Federation)
2. Institute of Spectroscopy, Russian Academy of Sciences, Troitsk, Moscow (Russian Federation)

We present the study of a source of extreme ultraviolet (EUV) radiation based on laser plasma generated due to the interaction of radiation from a nanosecond Nd : YAG laser with a liquidmetal droplet target consisting of a low-temperature eutectic indium–tin alloy. The generator of droplets is constructed using a commercial nozzle and operates on the principle of forced capillary jet decomposition. Long-term spatial stability of the centre-of-mass position of the droplet with the root-mean-square deviation of ∼0.5 μm is demonstrated. The use of a low-temperature working substance instead of pure tin increases the reliability and lifetime of the droplet generator. For the time- and space-averaged power density of laser radiation on the droplet target 4 × 10{sup 11} W cm{sup -2} and the diameter of radiating plasma ∼80 μm, the mean efficiency of conversion of laser energy into the energy of EUV radiation at 13.5 ± 0.135 nm equal to 2.3% (2π sr){sup -1} is achieved. Using the doublepulse method, we have modelled the repetitively pulsed regime of the source operation and demonstrated the possibility of its stable functioning with the repetition rate up to 8 kHz for the droplet generation repetition rate of more than 32 kHz, which will allow the source brightness to be as large as ∼0.96 kW (mm{sup 2} sr){sup -1}. (laser-plasma euv radiation source)

• OSTI ID: 22724636
• Journal Information: Quantum Electronics (Woodbury, N.Y.), Vol. 46, Issue 5; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1063-7818
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BRIGHTNESS
DROPLETS
ENERGY CONVERSION
EUTECTICS
EXTREME ULTRAVIOLET RADIATION
INDIUM ALLOYS
KHZ RANGE
LASER RADIATION
LASER TARGETS
LASER-PRODUCED PLASMA
LIQUID METALS
NEODYMIUM LASERS
POWER DENSITY
RADIATION SOURCES
TEMPERATURE RANGE 0065-0273 K
TIN ALLOYS