Silver nanopillar coatings grown by glancing angle magnetron sputtering for reducing multipactor effect in spacecrafts

We have studied nanometric high aspect ratio Ag nanopillar coatings exhibiting reduced secondary electron emission for the mitigation of multipactor effect in radio-frequency space devices of high frequency and high power. The Ag nanopillars have been grown by glancing angle deposition with DC magne...

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Detalles Bibliográficos
Autores: Troncoso, G., García-Martín, José Miguel, González Sagardoy, María Ujué, Morales, Carlos, Fernández Castro, Marcial, Soler-Morala, Jimena, Galán, Luis, Soriano, Leonardo
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2020
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/212937
Acceso en línea:http://hdl.handle.net/10261/212937
Access Level:acceso abierto
Palabra clave:Secondary electron emission
Anti-multipactor coatings
Ag nanopillars
Glancing angle deposition
Magnetron sputtering
Descripción
Sumario:We have studied nanometric high aspect ratio Ag nanopillar coatings exhibiting reduced secondary electron emission for the mitigation of multipactor effect in radio-frequency space devices of high frequency and high power. The Ag nanopillars have been grown by glancing angle deposition with DC magnetron sputtering. Some samples have been covered by a gold capping layer to reduce oxidation and aging effects. The secondary emission yield of the surfaces of these samples has been measured and compared to those of flat Ag and Au reference samples. The results show that high aspect ratio surface roughness at the nanometer scale significantly reduce the secondary emission yield of the surface. This reduction is more important for low electron energies, which is the most influencing energy range of electrons for multipactor. The multipactor region for the nanopillar coating presenting the best secondary emission yield properties has been simulated, finding practical suppression of multipactor effect. The high-frequency surface resistance of these samples has also been estimated from published computations for similar surface roughness patterns. It was found that such nanopillar coatings are compatible with the best accomplishments of present space industry.