Patent · US Expired

Cathode device having smaller opening

US5576594A · kind A · utility

11Cited by
13References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 6, 1995
Grant dateNov 19, 1996
Priority date
Expiry dateNov 6, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J31/127
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A cathode device comprising a plurality of emitter tips having conical tip end portions to emit electrons therefrom. A gate electrode layer has an opening through which the tip end portion of each of the emitter tips is exposed. The diameter of the opening in the gate electrode layer is made smaller than that of the portion of the emitter tip at the juncture thereof with the substrate. In the fabrication of the cathode device, an oxide layer is formed at least on the surface of the formed emitter tip to sharpen the latter. By removing the oxide layer, an inner circumferential wall of the opening of the gate electrode layer is formed on the outside of the conical tip end portion of the emitter tip and extends approximately in parallel to the conical tip end portion of the emitter tip.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.