Patent · US Expired

Fabrication process for microminiature electron emitting device

US5221221A · kind A · utility

15Cited by
8References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 22, 1991
Grant dateJun 22, 1993
Priority date
Expiry dateJan 22, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J9/025
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A process for fabricating an electron emitting vacuum type device having a tipped electron emitter supported on a substrate and disposed in a vacuum for emitting electrons. The process utilizes a substrate having opposed substantially planar front and rear surfaces. The front surface, carrying a series of conical depressions, is plated with a metallic layer of electron emitting material which lines the apertures to form metallic structures having tips buried in the substrate. A first material removal process, comprising grinding, is performed on the rear of the substrate to remove the bulk of the substrate but leaving the tips protected within the substrate. A second operation comprising a finishing operation is then applied to the rear surface to advance the plane of the rear surface from an as-ground to an as-finished position. The finishing operation employs a wet etching solution, and may employ mechanical friction (free of abrasive particles) to assist the speed of etching and uniformity of the finished surface. The as-finished plane of the surface serves to expose the metallic tips so that they can serve as emitters in a vacuum tube device.

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