Observations and analysis of extreme ultraviolet emission by capillary discharge with Xe as target

Abstract

The first capillary discharge produced plasma extreme ultraviolet source has been started in China. Fundamental characteristics of DPP including current, Xe gas pressure, extreme ultraviolet energy and spectrum in extreme ultraviolet region have been studied. A high voltage power source is employed, which voltage can be changed from 20kV to 30kV, and the current is from 25kA to 45kA with a FWHM of 120ns. The high voltage is loaded between the capillary which is 3mm in diameter and 12mm in length by injected Xe gas to achieve extreme ultraviolet radiation mostly in the region 10nm~18nm developed in framework of an extreme ultraviolet lithograph program. It is founded that the in-band (13.5nm, 2% bandwidth) energy is increasing with decreasing Xe gas pressure and/or increasing the current in the region 5~10Pa and 25kA~45kA.And 0.56J/2π sr/pulse energy (13.5nm, 2% bandwidth) can be got when the input energy is 47.7J, and the conversion efficiency is 0.56%.