Patent · US Expired

Filament for ion implanter plasma shower

US5856674A · kind A · utility

23Cited by
9References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 16, 1997
Grant dateJan 5, 1999
Priority date
Expiry dateSep 16, 2017

Classification

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

Abstract

A ribbon filament (86) is provided for a thermionic emission device. The filament comprises an elongated body having a configuration defined by a length, a width, and a thickness. The length comprises a central portion (96) and first and second end portions (98) on either side of the central portion. The width of the central portion is greater than that of the first and second end portions. In addition, the thickness of the filament is substantially less than the width along its entire length. The ribbon filament (86) may be configured as a single helical coil having its first and second end portions (98) mounted to first and second legs (85), respectively, at locations of slots therein. Preferably, the filament (86) is comprised of tungsten and the first and second legs (85) are also comprised of tungsten.

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