Journal of Vacuum Science & Technology B, Vol.21, No.1, 280-287, 2003
High-power collimated laser-plasma source for proximity x-ray nanolithography
A compact laser-produced plasma x-ray source radiates 1 nm x rays with an average power of 24 W in 2pi steradians. The x-ray conversion efficiency is 9% of the laser power delivered on target. The 300 W laser power is generated by a compact diode-pumped, solid-state Nd:YAG laser system. The point source x-ray radiation is collimated with a polycapillary optic to a parallel x-ray beam. The collimated plasma source (CPS) is used to demonstrate proximity x-ray lithography of 100 nm lines with a 16 mum gap between the mask and wafer. The CPS is optimized for integration with an x-ray stepper to provide a complete collimated plasma lithography exposure tool for the manufacture of high-speed GaAs devices. (C) 2003 American Vacuum. Society.