Pulsed microdischarge, 121.6 nm VUV source with 40 watt peak power

Summary form only given. A micro hollow cathode discharge VUV source, with time averaged power above 3 watts, and peak power above 40 watts is presented¹. Such operation is achieved by driving the microdischarge (MD) in the arc mode where high electron densities and low discharge impedances exist. Improved theoretical estimations regarding the timescales of arc formation are presented. With typical electrical sources, the arc regime is associated with a collapse of the potential and poor coupling of energy. However, the pulsed driver utilized in this study features a low output impedance, thus sustaining a reasonable voltage across the MD while simultaneously delivering 10s of amperes when the arc mode is achieved. This allows for time averaged input power on the order of 550 watts. Gas mixtures such as Ar-H₂ (99.7%/0.3% by volume) have demonstrated strong VUV emission at Lyman-α (121.6 nm), with measured power levels exceeding 40 watts peak.This study details the influence of the MD performance under various drive modes. Utilizing a pulse forming line based driver the behavior of the MD under 10 ns excitation and various repetition frequencies, with and without DC bias are presented. The MOSFET based low impedance driver, enables investigating the operation of the MD under high average input power. We will demonstrate the feasibility of utilizing the developed MD to achieve volume pre-ionization in appropriate target gases.