AVS 51st International Symposium
    Nanometer-scale Science and Technology Tuesday Sessions
       Session NS-TuM

Paper NS-TuM9
Electron Emission Property from MWCNTs with Subnano Ruthenium Dioxide Clusters and with High Adhesivity on Substrate - High Current Endurance Test in UHV and Influence of H@sub 2@O or CO -

Tuesday, November 16, 2004, 11:00 am, Room 213D

Session: Nanotube Processing and Composite Materials
Presenter: S. Kato, KEK, Japan
Authors: M. Shimamoto, KEK, Japan
T. Noguchi, KEK, Japan
M. Nishiwaki, KEK, Japan
K. Tatenuma, KAKEN Inc., Japan
S. Kato, KEK, Japan
Correspondent: Click to Email
Applications of MWCNTs to FEDs, electron sources of electron accelerators and surface analytical tools, and vacuum tubes for microwave amplifier, X-ray, light tube and so on require a high current density of its electron beams, a low threshold of electric field staring the field emission and a long life time with the emission. We reported the achievement of a remarkalbly high DC current density close to 300mA/cm@super 2@ with a threshold electric field of 2V/µm using new technologies of subnano RuO@sub 2@ clusters on MWCNTs surface and of high CNT adhesivity on metalic substrate. An outstanding electron emission property achieved after those treatments would be explainable based on both further increase emission points due to the subnano clusters not only from MWCNT ends but also from strongly bent wall and better thermal conductivity resulted from the heat treatment. Reduction of work function of CNT owing impregnation of RuO@sub 2@ might contribute higher field emission current density as well. Base pressure of XHV should be also big help to make sure reasonable MWCNT life at very high emission current to drastically reduce physical and chemical ion sputtering. In this paper, endurance running tests of MWCNTs in UHV up to 700 hours with a relatively high DC current of 50 mA/cm@super 2@ and degradation of the field emission characteristics due to residual gas such as H@sub 2@O or CO are focused.