A planar-type surface-wave plasma source with a subwavelength diffraction grating inclusion for large-area plasma applications

Abstract

The electromagnetic wave through the subwavelength diffraction grating can be largely absorbed by surface-wave plasmas (SWPs). A SWP source is built with two slot-array antennas element. Due to the dissipation of surface waves in overdense plasmas, this source can provide remarkable discharge efficiency of 4.4 cm2/W experimentally and 96% of incident power numerically. When the applied power as low as 200 W is supplied to the SWP source, a homogeneous plasma with the uniform area up to 14×36 cm2 and the plasma density up to 1.04×1018 m−3 is generated under the quartz slab. By varying the incident power and gas pressure, the parameter of plasmas can be easily controlled without density jumping. Moreover, the characters of bi-Maxwellian electron energy distribution prove that our SWP source yield plasmas by surface heating actually. These excellent performances make the proposed source meet the requirements in large-area plasma processing and also give its advices for plasmas heating in next meter-size SWP sources.

Effect of wave-mode conversion device on production of large-area rectangular overdense surface-wave plasmas at the gas pressure about 100 Pa

“…IV. Figure 1 show the schematic of the plasma source, which has been reported in our previous works, [16][17][18][19] but its energy coupling parts in the present setup will be reset for studying the influences of different wave-mode conversion devices on plasma heating. The cavity dimensions are x =0-46 cm, y =0-22 cm, and z =0-30 cm.…”

“…Therefore, the development and application researches of the large-scale overdense SWP have attracted the unprecedented attention and the current study focus on the spatial uniformity and the temporal stability in large area. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] To address the above concerns, a lot of planar-type SWP sources have been optimized. As for these sources, the uniformity of plasma below the dielectric slab is one of the most important factors.…”

Study on the electromagnetic waves propagation characteristics in partially ionized plasma slabs

“…1,2 Characterized by non-uniformity of plasma distributions, a high number density of neutral particles, a broad frequency range of electron-neutral collisions, the partially ionized plasma slabs have been studied extensively, for radio-frequency (rf) wave communication and control, material processing, and other applications. [3][4][5][6][7][8][9][10] Especially, the interaction between partially ionized plasmas and electromagnetic (EM) waves becomes a key issue not only in the fundamental studies, but also in the practical applications. [11][12][13] Take communication and control during spacecraft reentry for example, as to the case with a highly nonuniform plasma layer covering the vehicle, understanding of the interaction between EM waves and such typical plasmas is crucial to performance reliable communication, and extensively investigated.…”

Microwave power coupling in a surface wave excited plasma

“…9 In dielectric-bounded SWP sources, more than 200 W microwave power is injected. [1][2][3][4][5][6][7][8][9][10][11][12] In MVP sources, microwave plasmas are produced along a dielectric-free metal antenna and the surface waves propagate along the plasma-sheath interfaces. In 2005, Kousaka et al 13 at Nagoya University reported a new SWP source which can generate over-dense plasma along the surface of a negative biased metal rod, called metal-antenna surface wave excited plasma (MASWP).…”