Wüest M. 51 Wykes M. 82 Yamaguchi M. 17 Ybarra G. 129 Yubero F ...

JUNE 28 WEDNESDAY AFTERNOON
RIVA-SS-WeA-P.1 TiCr ALLOYS OF LOW SECONDARY ELECTRON EMISSION
FOR ANTIMULTIPACTOR APPLICATIONS. G. G. Fuentes and R. J. Rodríguez, AIN-Centro
de Ingeniería Avanzada de Superficies, Cordovilla, 31191, Pamplona, Spain. L. Galán, Departamento
de Física Aplicada. Universidad Autónoma de Madrid. Cantoblanco. 28049-Madrid. Spain. I.
Montero and J. L. Segovia, Instituto de Ciencia de Materiales de Madrid. CSIC. Cantoblonco.
28049-Madrid. Spain
TiCr alloys of low secondary electron emission have been investigated as potential anti-multipactor
coatings. Cathodic-arc evaporation technique in Ar atmosphere was used. The ion energy can be
controlled by the substrate biasing. Chemical state analysis and surface composition were obtained
by X-ray Photoemission Spectroscopy (XPS). Depth profiling was performed by Glow Discharge
Optical Emission Spectroscopy (GDOES). Scanning Electron Microscopy images show the formation
of grains on the surface. The film composition is homogeneous, however, the composition of the
grains varied with their size. Larger grains are richer in titanium, while small ones are rich in chromium
as indicated by energy Dispersive X-ray analysis. Total secondary electron emission yield was
determined by measuring the sample current to ground when bombarded by a primary electron beam
of determined energy. The secondary electron emission coefficient of TiCr alloy exposed to air was
lower than those of chromium or titanium coatings and their nitrides. The experimental secondary
emission yield values together with a Montecarlo model of the secondary emission process were
used to obtain the multipactor threshold.
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