Xenon excimer emission from pulsed high-pressure capillary microdischarges

Abstract

Intense xenon vacuum ultraviolet (VUV) emission is observed from a high-pressure capillary cathode microdischarge in direct current operation, by superimposing a high-voltage pulse of 50ns duration. Under stagnant gas conditions, the total VUV light intensity increases linearly with pressure from 400 to 1013mbar for a fixed voltage pulse. At fixed pressure, however, the VUV light intensity increases superlinearly with voltage pulse height ranging from 08to2.8kV. Gains in emission intensity are obtained by inducing gas flow through the capillary cathode, presumably because of excimer dimer survival due to gas cooling.

Optimizing drive parameters of a nanosecond, repetitively pulsed microdischarge high power 121.6 nm source

“…For similar deep VUV MD-VUV sources, efficiencies as high as 5-6% were reported [17] albeit at lower power. It should also be noted that Xe * 2 (172 nm) MD-VUV sources have demonstrated as high as 20-30% efficiency when driven by nanosecond timescale pulses at lower power [19][20][21]. However for many applications such as photolithography, a 172 nm device only holds modest advantage over existing systems.…”

Xenon excimer emission from multicapillary discharges in direct current mode

“…3,4,10,11 One way is by increasing the gas pressure which results in higher three body collision rates. The second method is increasing the current through the discharge.…”

“…This is better realized by the use of a capillary tube with a large length to diameter ratio. 10,11 In addition, the cathode fall with a deeper hole will provide a large cathode area to increase further concentration of the energetic electrons.…”

“…The decrease of the irradiance can be explained by the increase of the gas heating which destroys excited dimers. 10 To summarize the results, stable dc microdischarges in xenon have been established in the triple metal capillary tubes. The high irradiance requires both the high discharge current and the high pressure.…”

“…These n discharges in series with the excimer emission capability of the second continuum will open up the possibility for the development of a direct current (dc) excimer laser. [9][10][11] We have studied the dc microdischarges in triple multi capillary tubes at several ambient pressures ranging from 400 mbar to 1013 mbar but with a fixed flow rate of 100 sccm. The experimental set up for the triple capillary discharges is shown in Fig.…”