Improving the microwave window breakdown threshold by using a fluorinated, periodically patterned surface

Chen, C. H.; Chang, Chao; Liu, W. Y.; Sun, Jun; Huang, Huijun; Ke, Changfeng; Song, Wei; Teng, Yan; Wu, Xiaolong; Xie, Jinlong; Meng, Zhu; Li, S.; Fang, Jinyong; Wu, Ping; Zhang, L. J.

doi:10.1063/1.4826627

Cited by 19 publications

(4 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…PS has good mechanical properties and a high working temperature. In terms of these advantages, PS is one of the best candidate materials for vacuum solid surface insulation and has been widely used in pulsed power devices [6,7].…”

Section: Introductionmentioning

confidence: 99%

Low-temperature plasma polymerized fluorocarbon coating promotes surface charge dissipation in polystyrene

Zhang

et al. 2020

Nanotechnology

View full text Add to dashboard Cite

Polystyrene (PS) is a common insulating material in pulsed power devices, which has excellent and reliable insulation properties. However, the charge accumulation on the insulator surface seriously threatens its surface insulation property. Surface modification has been verified as an effective way for inhibiting surface charge accumulation. In this paper, plasma polymerized fluorocarbon (PPFC) coating was prepared by low-temperature plasma polymerization in the mixture of methyl-methacrylate and dodecafluoroheptyl-methacrylate (DFHMA). Compared with the untreated PS, the surface charge dissipation rate of PPFC coating is increased by more than 6 times. The introduction of DFHMA makes the coating have no obvious ageing effect after the storage, and has good reusability after the surface flashover. This work provides a new method for modification of polymer dielectrics and a novel way for the preparation of high-charge-dissipation polymers in other related fields.

show abstract

Section: Introductionmentioning

confidence: 99%

Low-temperature plasma polymerized fluorocarbon coating promotes surface charge dissipation in polystyrene

Zhang

et al. 2020

Nanotechnology

View full text Add to dashboard Cite

show abstract

“…Finally, a final breakdown happens after electron-induced gas desorption accumulates sufficiently high local neutral pressure before a Townsendlike plasma discharge occurs [11]. The flashover mitigation is therefore driven by local field optimization [12][13][14], multipactor suppression [15][16][17], and neutral desorption reduction [18]. This paper introduces an innovative method focusing on multipactor suppression to mitigate the vacuum flashover.…”

Section: Introductionmentioning

confidence: 99%

“…Zhang et al [24] analyzed different groove shapes and discovered trapezoid grooves to be the optimal shape distribution of microstructures. In addition, material-based approaches such as plasma treatment [25], fluorinations [16], and doping ceramics [26,27] were also proved to be feasible modification techniques for SEY reduction. However, the studies on SEY reduction mentioned above all work on a dielectric with a SEY that is still greater than 1, and the modifications have to be conducted throughout the whole dielectric surface with a complicated procedure.…”

Section: Introductionmentioning

confidence: 99%

Metal-wire-embedded alumina insulating material using micro- and nanoscale 3D printing for surface flashover mitigation in a vacuum

Mu¹,

Yao²,

Zhang³

et al. 2022

J. Phys. D: Appl. Phys.

View full text Add to dashboard Cite

Micro and nanoscale 3D printing technic is applied to fabricate functional insulating material which mitigates surface discharge in vacuum based on the microscopic electron multipactor suppression. The proposed alumina ceramic insulator design consists surface-embedded thin metal wires which introduce a local gradient of secondary electron emission yield, such that the trajectories of multipactor electrons are distorted by accumulated negative surface charges and the secondary electron emission avalanche across the insulator surface is intermitted. Considerable increases of surface flashover threshold and surface charging reduction are verified by experiment. Also, additional efforts are made to determine the optimal size and spatial distribution of the metal wire. A convex-shape flashover voltage trace is observed when increasing the wire width, suggesting a trade-off between the multipactor mitigation and the insulator strength. Wire position between the adjacency of cathode triple junction and middle of the insulator is proved to be favorable for flashover mitigation. The physical details of surface flashover mitigation by the proposed insulator design are revealed by an ab initio particle-in-cell (PIC) simulation code, corroborating the experiment from microscopic aspect.

show abstract

“…Surface treatment on metals has long been researched, mainly including Alodine coatings [8,9], inert metal coatings, surface amorphous carbonation [10][11][12][13][14][15][16][17] and roughening [18][19][20][21][22][23][24][25]. In the field of rough surfaces, some aspects, such as calculations and mechanisms, have been well-defined [26,27] while experimental studies continue to prosper.…”

Section: Introductionmentioning

confidence: 99%

Effect of the Surface Morphology of Porous Coatings on Secondary Electron Yield of Metal Surface

Peng

Lin

Zhang³

et al. 2022

Materials

View full text Add to dashboard Cite

Surface roughening is an important material surface treatment technique, and it is particularly useful for use in secondary electron yield (SEY) suppression on metal surfaces. Porous structures produced via roughening on coatings have been confirmed to reduce SEY, but the regulation strategy and the influence of process parameters both remain unclear in the practical fabrication of effective porous structures. In this paper, the effect of the surface morphology of porous coatings on the SEY of aluminum alloy substrates was studied. Surface characterization and SEY measurements were carried out for samples with a specific process technique on their surfaces. An exponential fitting model of the correlation between surface roughness and the peak values of SEY curves, δm, was summarized. Furthermore, an implementation strategy to enable low surface SEY was achieved from the analysis of the effect of process parameters on surface morphology formation. This work will aid our understanding of the effect of the irregular surface morphology of porous coatings on SEY, thereby revealing low-cost access to the realization of an easy-to-scale process that enables low SEY.

show abstract

Improving the microwave window breakdown threshold by using a fluorinated, periodically patterned surface

Cited by 19 publications

References 22 publications

Low-temperature plasma polymerized fluorocarbon coating promotes surface charge dissipation in polystyrene

Low-temperature plasma polymerized fluorocarbon coating promotes surface charge dissipation in polystyrene

Metal-wire-embedded alumina insulating material using micro- and nanoscale 3D printing for surface flashover mitigation in a vacuum

Effect of the Surface Morphology of Porous Coatings on Secondary Electron Yield of Metal Surface

Contact Info

Product

Resources

About