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

Abstract

A high average power dense plasma focus (DPF), x-ray point source has been used to produce ∼70 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 4π steradians at ∼1 keV effective wavelength in ∼2 Torr neon at pulse repetition rates up to 60 Hz, with an effective x-ray yield efficiency of ∼0.8%. Plasma temperature and electron concentration are estimated from the x-ray spectrum to be ∼170 eV and ∼5·1019 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.

Approach to the Highest HXR Yield in Plasma Focus Device Using Adaptive Neurofuzzy Inference System to Optimize Anode Configuration

“…Ion beams of desired gas are generally used for surface treatments [8,9] as well as neutron beams for neutronic detection of hydrogen in samples [10,11] and lithography by means of electron beams [12,13]. X-rays, in particular, have extensive applications such as X-ray microscopy, X-ray lithography, micromachining, radiography, and material synthesis [14][15][16][17][18][19][20][21]. Radiography of the biological samples and X-ray imaging of moving metallic objects are two of the most noticeable applications of radiated hard X-ray in PF devices.…”

Application of an impedance matching transformer to a plasma focus

“…[8][9][10] Petr et al reported a 40% standard deviation in Neon K-shell yield so a 61% variation in neutron yield does not seem unreasonable considering that the DD fusion reaction relies on nonthermal processes, while the K-shell production relies on thermal physics with some contribution of non-thermal physics. 3 A key point is to compare the neutron yield from the transformer-based plasma focus with a conventional plasma focus pulse power system. As shown in Fig.…”

“…1,2 Petr et al demonstrated a solid state switched plasma focus system that operated for 10 7 pulses in Ne for lithography applications. 3 Many of the perceived problems of pulse power driven radiation sources were addressed including reliable pulse power, electrode lifetime and insulator lifetime. The working gas flowed, which maintained a fresh supply of gas in the chamber.…”

Correlation of Neutron and X-ray Emission from Plasma Focus with Pre-ionization

“…Plasma focus (PF) is among the low-priced available neutron and ions generators, with unique features of extremely short pulses (hundreds of ns) that suit it for different interesting applications [3][4][5][6]. Similarly, the soft X-rays emitted from PF have attracted the many researchers due to large numbers of application such as high brightness source for lithography in order to fabricate the electronic devices, X-ray laser pumping, X-ray Microscopy, X-ray backlighting and radiography [7][8][9][10][11][12].…”