25 W of average power at 172 nm in the vacuum ultraviolet from flat, efficient lamps driven by interlaced arrays of microcavity plasmas

Foundations of atmospheric pressure non-equilibrium plasmas

“…h) Front view of a 10cm x 10cm Xe 2 VUV (172nm) lamp consisting of an array of encapsulated microplasmas operating in 70% Xe/Ne admixture at 550 Torr. Reprinted from [81], with the permission of AIP Publishing. i) MW microplasma array operating in 100 Torr argon.…”

The 2017 Plasma Roadmap: Low temperature plasma science and technology

“…Plasma jets, generated in air or argon and driven at 2.45 GHz, are now offered at power levels from 5 to 400 W for applications ranging from surface cleaning and medical therapeutics at low power, to cutting and coating processes for P > 100 W. A second example is the realization of planar, high power vacuum ultraviolet (VUV)/UV lamps. For example, by interlacing two or more arrays of microcavity plasmas, 25 W of average power and more than 800 W of peak power can be generated at 172 nm from thin, flat lamps with a surface area of 10 × 10 cm 2 [15]. Microchannel plasma systems for disinfecting water with ozone have also been commercialized.…”

“…These multichannel ('massively parallel') processing architectures offer two advantages relative to conventional technology: (1) exploiting the advantages inherent to microplasmas, including power loading of the plasma and operating pressures, to produce the chemical species of interest, and (2) providing for redundancy in the system in a straightforward and inexpensive manner. This trend will continue, and the integration of microchannel or microcavity reactors with efficient optical sources [15] will result in hybrid plasmachemical/photochemical systems capable of driving the gas phase chemistry further from equilibrium than has been possible in the past. This development bodes well for realizing plasma chemistries capable of synthesizing products not available with current industrialscale chemical processing, but yet also competitive economically with the equilibrium thermal processing that has been the commercial standard for more than a century.…”

Microplasmas for Advanced Materials and Devices

“…Microplasmas are efficient emitters in the UV and VUV spectral regions. Research of the past two decades into the spectral and electrical properties of microplasma arrays recently culminated in the demonstration of flat lamps generating more than 25 W of average power at 172 nm from the Xe 2 molecule in the VUV region . Capable of realizing intensities greater than 300 mW cm −2 at pulse repetition frequencies above 130 kHz, these lamps comprise two interlaced arrays of microcavities and offer active areas of ≈90 cm 2 , a spectral bandwidth of roughly 9 nm, and peak (instantaneous) intensities above 600 W. The reported intensity and average power for these lamps are unprecedented in the VUV spectral region (wavelengths of 100–200 nm) which has been dominated by low power lamps for more than a century.…”