Work

Glow-to-arc transition in graphite cathode with high-current magnetron discharge

Year: 2024

Type: article

Abstract: The glow-to-arc transition is a critical phenomenon in plasma discharges, commonly leading to detrimental effects. The physical mechanisms triggering this transition remain poorly understood. The advent of a discharge called Hyper-Power Impulse Magnetron has opened possibilities. Hyper-Power Impulse Magnetron allows the glow mode to be maintained over long periods (1 ms) and at high-current densities (>5 A .cm−2), which has unveiled certain features in the glow-to-arc transition. This work focuses on a graphite target that transits easily in the arc regime. The high-speed video-camera analysis revealed specific properties of graphite in ExB discharges, and the statistical study of the arc transition revealed differences from other refractory target materials. The early stage of cathodic spot formation, observed as bright dots, will be presented and analyzed within the known “ecton” and “vaporization” models for spot formation. This experimental study highlights the role of luminous spot formation prior to arc transition, with possible optimization on the stability of magnetron discharges.

Source: Applied Physics Letters

DOI: 10.1063/5.0238958

Authors: Erwan Morel, Yoann Rozier, Tiberiu Minea

Institutions: Centre National de la Recherche Scientifique, Université Paris-Saclay, Laboratoire de Physique des Gaz et des Plasmas, Supergrid Institute, Supélec

Language: English

Topic: Vacuum and Plasma Arcs

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funder: Agence Nationale de la Recherche

Award: G6062483920