Performance summary on a high power dense plasma focus x-ray lithography point source producing 70 nm line features in AlGaAs microcircuits

A high average power dense plasma focus (DPF), x-ray point source has been used to produce similar to70 nm line features in AlGaAs-based monolithic millimeter-wave integrated circuits (MMICs). The DPF source has produced up to 12 J per pulse of x-ray energy into 4pi steradians at similar to1 keV effective wavelength in similar to2 Torr neon at pulse repetition rates up to 60 Hz, with an effective x-ray yield efficiency of similar to0.8%. Plasma temperature and electron concentration are estimated from the x-ray spectrum to be similar to170 eV and similar to5.10(19) cm(-3), respectively. The x-ray point source utilizes solid-state pulse power technology to extend the operating lifetime of electrodes and insulators in the DPF discharge. By eliminating current reversals in the DPF head, an anode electrode has demonstrated a lifetime of more than 5 million shots. The x-ray point source has also been operated continuously for 8 h run times at 27 Hz average pulse recurrent frequency. Measurements of shock waves produced by the plasma discharge indicate that overpressure pulses must be attenuated before a collimator can be integrated with the DPF point source. (C) 2004 American Institute of Physics.