| 摘要 |
<p>PURPOSE:To take out large probe current stably by adsorbing a particular metal through oxygen within the depth of mono atomic layer on the surface of area where electrons are emitted from a needle cathode. CONSTITUTION:In a vacuum container ambient where the field emission can be performed, at least one metal selected from Cr, Al, Ce, Mg, Ti, Si is deposited on the surface of area where at least the electron is emitted from a needle electrode 1 with the depth approximately same with that of mono atomic layer. Thereafter proper amount of oxygen gas is provided into the vacuum ambient to adsorb the oxygen gas with the depth approximately same with that of monomolecular layer on the metallic monomolecular layer, then the oxygen gas is evacuated to return to the ambient where the field emission can be performed. Thereafter the needle cathode 1 is heated for 10-60sec under the temperature range of 1,300-1,500 deg.C.</p> |
