Fig. 1. Experimental setup for laser-induced discharge produced plasma

Fig. 2. Laser intensity and waveforms of voltage and current in LDP when voltage is 15 kV

Fig. 3. EUV spectra of LPP and LDP at different voltages

Fig. 4. Total radiation power and EUV radiation power of laser produced plasma when laser energy is 145 mJ

Fig. 5. Simulation results of radiation distribution of laser plasma. (a) Average ionization degree distribution of tin ions;(b) EUV radiation power density distribution

Fig. 6. Total radiation powers and EUV radiation powers of LDP when voltages are 7 kV and 15 kV

Fig. 7. Simulation results of radiation distribution of LDP (voltage is 7 kV). (a) Average ionization degree distribution of tin ions; (b) EUV radiation power density distribution

Fig. 8. Simulation results of radiation distribution of LDP (voltage is 15 kV).(a) Average ionization degree distribution of tin ions; (b) EUV radiation power density distribution

Fig. 9. UTA between different Sn¹²⁺ excited states. (a) 4p⁶4d²→4p⁶4d4f; (b) 4p⁶4d4f →4p⁶4f²; (c) 4p⁶4d²→4p⁵4d³; (d) 4p⁵4d³→4p⁴4d⁴