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Theses
dépôts multicouches Fe/W sur substrat de Fe par pulvérisation magnétron D.C.
dépôts multicouches Fe/W sur substrat de Fe par pulvérisation magnétron D.C.
Abstract : The shadow mask of cathode-ray tubes is an element which exploits a part of the quality of pictures. Grid mask shadow is an iron plate (Fe) oxidized in the form of magnetite (Fe3O4). Electronic bombardment submitted to the shadow mask induces a doming. Then contrast and brightness can be weak. This study is thus related to the definition, development and characterization of a protective coating on the mask dealing with temperature gradient reduction. The selected material for this protective coating are tungsten (W) and iron (Fe). Tungsten is a refractory material with high electron backscattering coefficient. Moreover, magnetite has a good thermal emissivity coefficient. These two properties are essential to avoid the deformation due to the variation in temperature. During these three years of thesis, we studied the deposits of thin layers (double-layered system) Fe3O4/W but also alloy Fe-W on Fe substrate (material of the shadow mask). The deposits were carried out using simple or pulsed DC magnetron sputtering. An auxiliary discharges can be created to assist deposition using an internal radiofrequency antenna. For obtaining Fe3O4 thin films, we studied Fe thin film oxidations after deposition and in-situ during or after deposition.
Characterization where conducted to determine structure, composition, adhesion, and emissivity measurements.
Characterization where conducted to determine structure, composition, adhesion, and emissivity measurements.
Cited literature [52 references]
https://tel.archives-ouvertes.fr/tel-00123902
Contributor : Pascale Plantin <>
Submitted on : Thursday, January 11, 2007 - 2:08:10 PM
Last modification on : Thursday, March 5, 2020 - 6:48:55 PM
Long-term archiving on: : Tuesday, April 6, 2010 - 8:53:34 PM
Contributor : Pascale Plantin <>
Submitted on : Thursday, January 11, 2007 - 2:08:10 PM
Last modification on : Thursday, March 5, 2020 - 6:48:55 PM
Long-term archiving on: : Tuesday, April 6, 2010 - 8:53:34 PM