Coupled phenomena in arrays of microplasma devices and microchannel plasma devices as antennas

Microplasmas;optical coupling;electrical coupling;antennas

Sung, Seung Hoon

关键词: Microplasmas;    optical coupling;    electrical coupling;    antennas;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/18565/Sung_Seung%20Hoon.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Arrays of microcavity and microchannel plasmas with characteristic dimensions of 25-800 micrometer have been generated in glass substrates. To reproducibly fabricate the arrays, glass micromaching using replica molding and micropowder blasting was proposed and demonstrated. The microplasmas were optically and electrically probed in this work.The investigation showed that each plasma is physically separated and yet, under the proper conditions, is optically and/or electrically coupled to its neighbors. In arrays as large as 10 parallel microchannel plasmas, evidence of optical coupling among the channels is observed in the form of strongly enhanced atomic emission which is attributed to electron heating driven by the resonant absorption of scattered radiation. The transition from Townsend-like discharges to abnormal glow-like discharges was observed in arrays of microcavity plasma devices. During the transition, bistable oscillations of visible emission wereobserved in microcavity plasma devices operating in Ne at pressures of 200-700 Torr. In this situation, the time-varying distribution of charge depositedon a dielectric layer in a dielectric barrier device structure appears to be responsible for the oscillations and coupling. It was also observed, in arrays of microcavity plasma devices with a gap, that free microdischarges interactwith bounded microdischarges over a distance of less than 500 micrometer. In addition, this work explored and demonstrated the possibility of using microchannel plasma devices as antennas. The measured transmission of RF signals and theoretical predictions of the plasma conductivity show that metal antennas can be replaced by microchannel plasmas. The simulated results also suggest that MHz domain frequency is required to drive microchannel plasma antennas in a quasi-continuous mode. Operation ofmicroplasma channels as receiving antennas was also observed in a planar microstrip configuration.