A requirement for the development of EUV (5-50 nm) laser applications is a pulse power driver system that can deliver high peak currents and fast rise-times in order to be able to pump these lasers effectively. We report here the initial results in the development of a high current driver that is efficient, compact and scalable for EUV lasers.The pulse power driver is based on a low inductance integrated multiple-capacitor assembly developed by Specscan Sdn. Bhd and was tested on a well-established capillary-discharge 46.9nm Ne-like Ar laser. The pulse power driver comprises four (4) folded aluminum foil and dielectric film capacitors arranged in a two-stage LCinversion circuit. These are built into a compact 0.5 m square assembly with a pair of input bar electrodes mounted on one side and output bar electrodes on the opposite side. Twenty (20) equal lengths of HV coaxial cables are used as transmission lines connecting the output bar electrodes to a capillary discharge device. A pressurized spark-gap switch is attached to the input bar electrodes, and the system is charged with +10kV and -10kV across the input terminals, requiring a total input energy of 20.6J. Upon triggering, a quadruple increase in output voltage of approximately 40 kV is obtained.The pre-ionized capillary discharge device uses a 10 cm long alumina tube with inner and outer diameters of 2.8 and 5.6 mm respectively. Triggering the pulse power device, a discharge in Ar with a peak current of around 15.5 kA and a quarter wave rise rime of 40 ns was measured. A fast photodiode with appropriate filters was used to measure a laser pulse emitted at 46 ns from the beginning of the discharge and 6 ns after the current peaked. Using these measured values, a total circuit inductance of 25.7 nH was derived and is close to the value estimated from the physical dimensions of the discharge loop circuit.Of particular interest to note is that the new driver system requires only 20 J of input energy in order to generate 15kA of peak discharge current (i.e. at 750 A/J). This is to be compared to existing capillary discharge driver systems that can generate up to 200 kA peak current but requiring up to 8 kJ of energy input (i.e. at 25 A/J). Scaling of the new driver system can be expected in the future by increasing the operating voltage and capacitance and will be discussed.

In recent years, there have been various developments of highcurrent discharge drivers used in pulsed-power technologies including linear transformer drivers and impedance-matching transformers. As the discharge current scales up, it becomes crucial to optimize the input energy requirements. A new system was designed to provide a scalable low inductance current driver suitable for pulse-power applications including z-pinch, plasmafocus, and other direct current drive applications. This paper explores the development of a new current driver for a system with a z-pinch load using six modular units of low inductance integrated multiple-capacitor assemblies developed by Specscan Sdn. Bhd. Each of these modular units comprise four folded aluminum foil and dielectric film capacitors arranged in a twostage LC-inversion circuit. Six of these modular multi-capacitor assemblies were connected to a pair of hexagon-shaped transmission plates of 1 meter in diameter with a z-pinch load located in the center to form a voltage-discharge loop for an estimated loop circuit inductance of 6.31 nH. Six individual spark-gap switches were connected to the voltage inversion loops of the multi-capacitor assemblies. Voltages of +6.75 kV and -6.75 kV were applied across the switches to charge the capacitors requiring 280 J of total input energy. The switches were then triggered simultaneously to generate a voltageinversion that provides a near-quadruple increase in voltage across the transmission plates to form a pulse-energy driver system. A peak voltage of approximately 24.4 kV was obtained at the z-pinch load with a peak current of 211 kA and a quarterwave 10-90% rise time of 110 ns. The system generated 4.6 GW of peak power with a corresponding efficacy of 16.5 MW/J. This development illustrates a concept of an efficient scalable direct high current driver system for various pulse power applications using relatively low voltages. One particular interest in the future is the possibility of scaling these drivers to operate in the megaamperes range. This can be achieved if: a) the charging voltages are increased; and b) if the transmission plates are enlarged to accommodate a greater number of modular multi-capacitor units. This paper will describe how the existing z-pinch system operates and the results obtained. Projections will then be made on its potential current scaling while maintaining its input energy efficiencies.