Patent ID: 6798126
Filing Date: 2004-09-28
Classification: H01J

Abstract:
A method of forming an electron emitter, comprising:providing an emitter including tungsten; electrochemically etching a tip on the emitter, the tip having an end radius of less than about 0.4 &mgr;m and cone angle of less than about 15 degrees; depositing a material comprising zirconium oxide on a portion of the emitter away from the tip; and heating the emitter sufficiently to diffuse zirconium oxide from the portion of the emitter away from the tip to the tip but not sufficiently to change the shape of the tip to the extent that emission characteristics are significantly degraded, electromechanically etching the tip on the emitter and heating the emitter sufficiently to diffuse zirconium oxide producing an emitter capable of producing greater that 1.5 mA/sr using a total emission current of less than 750 &mgr;A.