Electron field emission from surface treated tetrahedral amorphous carbon films
نویسندگان
چکیده
The electron field emission properties of tetrahedral amorphous carbon thin films deposited using a filtered cathodic vacuum arc system have improved as a result of surface treatment with H, O, and Ar ions. The limiting factor of the emission process does not appear to be only the front surface of the films. The improvement in the emission after ion beam treatment appears to be independent of the ions used. The surface which has been analyzed using ultraviolet photospectroscopy, reflected electron energy loss spectroscopy, and scanning tunneling microscopy shows evidence of the creation of segregated sp and sp rich regions of less than 20 nm in dimension. An extension to the space charge-induced band bending model including a multistep emission process that occurs in this mixed phase material is proposed. © 1999 American Institute of Physics. @S0003-6951~99!02304-9#
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