PURPOSE: To provide a cold electron emitting electrode having excellent cold electron emitting performance, a low discharge voltage, and a long usable time (life).
CONSTITUTION: A metal powder 1 on the surface of which a composite oxide thin film 2 of at least one kind of alkali metals and alkali earth metals and a metal forming a constituting component is formed is molded into a determined form and thermally treated, whereby a porous body 3 is formed. In the manufacture of a cold electron emitting electrode, the metal powder is dipped in an aqueous solution for treatment containing at least one kind of alkali metal ions and alkali earth metal ions and hydrothermally treated at a temperature of 100°C or more, whereby the composite oxide thin film of the metal and the metal ion is formed on the surface of the metal powder, and the metal powder having the composite oxide thin film formed thereon is molded into a determined form followed by thermal treatment.
WADA RYUICHIRO
HAMACHI YUKIO
