Cathode commutable à nanotubes de carbone pour tube à rayons X

Abstract : This work chooses to improve the electron source by replacing thermionic emission with field emission. More especially, carbon nanotubes based cold cathodes stand out by their ability to supply high currents (>1A/cm^2) while responding fast.Through the development of an innovative structure of in-plane gated carbon nanotube based cathode, this study aims at making switchable and regulated sources for miniature, portable or polyvalent X-rays sources.The electrostatic modelling of the new structure led to the fabrication of optimized gated cathodes, where a vertically aligned array of carbon nanotubes is grown. Default analysis allows to get reliable insulated devices.Field emission characterization shows unprecedented current modulation of 10^6 at +/-40V bias voltage. Current regulation is also achieved with a stability of 0.02% over 100 h.Another structure with a burried gate electrode was designed to successfully cope with leak current and parasitic growth. A new way of growing short and thin nanotubes was tackled.Finally, gated cathodes were integrated in a compact X-ray tube and showed a current modulation of 2000 at a high voltage of 60 kV.
Complete list of metadatas

Cited literature [236 references]  Display  Hide  Download

https://pastel.archives-ouvertes.fr/tel-01505076
Contributor : Abes Star <>
Submitted on : Tuesday, April 11, 2017 - 8:33:10 AM
Last modification on : Thursday, April 11, 2019 - 7:51:23 AM
Long-term archiving on : Wednesday, July 12, 2017 - 12:33:38 PM

File

59001_SABAUT_2016_archivage.pd...
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01505076, version 1

Citation

Lucie Sabaut. Cathode commutable à nanotubes de carbone pour tube à rayons X. Micro et nanotechnologies/Microélectronique. Université Paris-Saclay, 2016. Français. ⟨NNT : 2016SACLX078⟩. ⟨tel-01505076⟩

Share

Metrics

Record views

439

Files downloads

267