TY - JOUR
T1 - New type of discharge-produced plasma source for extreme ultraviolet based on liquid tin jet electrodes
AU - Koshelev, K.N.
AU - Krivtsun, V.M.
AU - Ivanov, V.
AU - Yakushev, O.
AU - Chekmarev, A.
AU - Koloshnikov, V.
AU - Snegirev, E.
AU - Medvedev, Viacheslav
PY - 2012
Y1 - 2012
N2 - A new approach for discharge-produced plasma (DPP) extreme ultraviolet (EUV) sources based on the usage of two liquid metallic alloy jets as discharge electrodes has been proposed and tested. Discharge was ignited using laser ablation of one of the cathode jets. A system with two jet electrodes was tested at a repetition rate of 1 to 5 kHz with dissipated electrical power up to 20 kW. Radiating spectra, time characteristics, and conversion efficiency are similar to conventional DPP schemes with rotating wheels. In the first experiments, the Ga:Sn eutectic alloy, which is liquid at room temperature, was circulating in a closed loop. The high velocity of the jets (30 m/s
30 m/s
) ensures a renewed electrode surface for every shot, for a repetition rate frequency of up to 30 to 50 kHz, and provides effective heat transportation from the discharge zone. Modeling and experiments demonstrate that the proposed scheme is able to dissipate up to 200 kW of electrical power without overheating the nozzles and tin surface. It was found that the flexible electrode configuration allows the channeling of essential parts of debris plasma in directions opposite to the EUV collector.
AB - A new approach for discharge-produced plasma (DPP) extreme ultraviolet (EUV) sources based on the usage of two liquid metallic alloy jets as discharge electrodes has been proposed and tested. Discharge was ignited using laser ablation of one of the cathode jets. A system with two jet electrodes was tested at a repetition rate of 1 to 5 kHz with dissipated electrical power up to 20 kW. Radiating spectra, time characteristics, and conversion efficiency are similar to conventional DPP schemes with rotating wheels. In the first experiments, the Ga:Sn eutectic alloy, which is liquid at room temperature, was circulating in a closed loop. The high velocity of the jets (30 m/s
30 m/s
) ensures a renewed electrode surface for every shot, for a repetition rate frequency of up to 30 to 50 kHz, and provides effective heat transportation from the discharge zone. Modeling and experiments demonstrate that the proposed scheme is able to dissipate up to 200 kW of electrical power without overheating the nozzles and tin surface. It was found that the flexible electrode configuration allows the channeling of essential parts of debris plasma in directions opposite to the EUV collector.
KW - METIS-313940
KW - IR-98810
U2 - 10.1117/1.JMM.11.2.021103
DO - 10.1117/1.JMM.11.2.021103
M3 - Article
SN - 1932-5150
VL - 11
SP - 021103-1-021103-6
JO - Journal of micro/nanolithography, MEMS, and MOEMS
JF - Journal of micro/nanolithography, MEMS, and MOEMS
IS - 2
ER -