Patent · US Expired

Endcap for indirectly heated cathode of ion source

US5703372A · kind A · utility

34Cited by
8References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 31, 1996
Grant dateDec 30, 1997
Priority date
Expiry dateDec 31, 2016

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01J2237/31701
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An ion source for use in an ion implanter. The ion source comprises a gas confinement chamber having conductive chamber walls that bound a gas ionization zone. The gas confinement chamber includes an exit opening to allow ions to exit the chamber. A base positions the gas confinement chamber relative to structure for forming an ion beam from ions exiting the gas confinement chamber. A portion of a cathode extends into an opening in the gas confinement chamber. The cathode includes a cathode body defining an interior region in which a filament is disposed. The cathode body comprises an inner tubular member a coaxial outer tubular member and an endcap having a reduced cross section body portion with a radially extending rim. The endcap is pressed into the inner tubular member. The filament is energized to heat the endcap which, in turn, emits electrons into the gas ionization zone. The filament is protected from energized plasma in the gas ionization zone by the cathode body.

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