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US5554852A Expired / Lapsed US ⏱️ 0.0 years remaining

Ion implantation having increased source lifetime

Assignee: Applied Materials Inc
•
Filing: 1995-04-03
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Granted: 1996-09-10
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Expires: 2015-04-03
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Abstract

Abstract Ion implantation equipment is modified so as to provide filament reflectors to a filament inside of an arc chamber, and to remove the electrical insulators for the filament outside of the arc chamber and providing a shield, thereby reducing the formation of a conductive layer on said insulators and greatly extending the lifetime and reducing downtime of the equipment. The efficiency of the equipment is further enhanced by an interchangeable liner for the arc chamber that increases the wall temperature of the arc chamber and thus the electron temperature. The use of tungsten parts inside the arc chamber, obtained either by making the arc chamber itself or portions thereof of tungsten, particularly the front plate having the exit aperture for the ion beam, or by inserting a removable tungsten liner therein, decreases contamination of the ion beam. Serviceability of the arc chamber is improved by using a unitary clamp that separately grips both the filament and filament reflectors. This clamp can also advantageously be made of tungsten.

Inventors

  • 👤 Nicholas Bright
  • 👤 Paul A. Burfield
  • 👤 John Pontefract
  • 👤 Bernard F. Harrison
  • 👤 Peter Meares
  • 👤 David R. Burgin
  • 👤 Andrew S. Devaney
  • 👤 Peter T. Kindersley

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 22:59
CPC Classifications
H; H01; H01J; H01J27/00; H01J27/02; H01J27/16; H01J27/18; H01J27/022; H01J27/08; H01J2237/00; H01J2237/30; H01J2237/317; H01J2237/31701; H01J2237/31705

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 85 words
In an ion implantation system comprising an ion source including an arc chamber for producing an ion beam of a preselected chemical species at a predetermined beam current level, beam analyzing means for receiving said beam and selectively separating various ion species on the basis of mass to produce an analyzed beam, and beam resolving means for permitting said separated species to pass to a target to be implanted, the improvement which comprises using tungsten as the material of the source or a portion thereof.
Claim 2
Dependent Claim 85 words
In an ion implantation system comprising an ion source including an arc chamber for producing an ion beam of a preselected chemical species at a predetermined beam current level, beam analyzing means for receiving said beam and selectively separating various ion species on the basis of mass to produce an analyzed beam, and beam resolving means for permitting said separated species to pass to a target to be implanted, the improvement which comprises using tungsten as the material of the source or a portion thereof.
Claim 3
Dependent Claim 21 words
An ion implantation system according to claim 1 wherein one or more walls of said arc chamber is made of tungsten.
Claim 4
Dependent Claim 24 words
An ion implantation system according to claim 2 wherein the front plate having an exit aperture for said ion beam is made of tungsten.
Claim 5
Dependent Claim 17 words
An ion implantation system according to claim 2 wherein said arc chamber has a removable tungsten liner.
Claim 6
Dependent Claim 17 words
An ion implantation system according to claim 1 wherein said arc chamber has a removable tungsten liner.
Claim 7
Dependent Claim 27 words
An ion implantation system according to claim 1 wherein said arc chamber has a filament therein and a reflector therefor, wherein said reflector is made of tungsten.
Claim 8
Independent Claim 81 words
A method of improving the ionization efficiency of an ion source having an arc chamber including a filament therein in an ion implantation apparatus which comprises lining the walls of the arc chamber with a removable refractory material so that heat generated in the arc chamber when power is fed to the filament and the arc chamber plasma, is transferred by the liner to the walls of the arc chamber by radiation, thereby increasing the electron temperature of the arc chamber.
Claim 9
Independent Claim 81 words
A method of improving the ionization efficiency of an ion source having an arc chamber including a filament therein in an ion implantation apparatus which comprises lining the walls of the arc chamber with a removable refractory material so that heat generated in the arc chamber when power is fed to the filament and the arc chamber plasma, is transferred by the liner to the walls of the arc chamber by radiation, thereby increasing the electron temperature of the arc chamber.
Claim 10
Dependent Claim 25 words
A method according to claim 7 wherein said liner is separated from the walls of the arc chamber by a gap of about 0.1 mm.
Claim 11
Dependent Claim 25 words
A method according to claim 7 wherein said refractory material is selected from the group consisting of carbon, glassy carbon, silicon carbide, molybdenum and tungsten.
Claim 12
Dependent Claim 12 words
A method according to claim 9 wherein said refractory material is tungsten.
Claim 13
Dependent Claim 59 words
In an arc chamber for generating ions including a filament connected to a source of current, a source of gas for generating a plasma and an exit aperture in a front plate of said arc chamber for extracting a beam of ions from said chamber, the improvement which comprises said front plate having said exit aperture made of tungsten.
Claim 14
Dependent Claim 59 words
In an arc chamber for generating ions including a filament connected to a source of current, a source of gas for generating a plasma and an exit aperture in a front plate of said arc chamber for extracting a beam of ions from said chamber, the improvement which comprises said front plate having said exit aperture made of tungsten.
Claim 15
Dependent Claim 47 words
An arc chamber according to claim 11 further including a replaceable refractory liner for said chamber and maintaining an insulating gap between said liner and walls of the arc chamber so that the walls of the chamber are heated by radiation from said liner to said walls.
Claim 16
Dependent Claim 30 words
An arc chamber according to claim 12 wherein said liner is made of a refractory material selected from the group consisting of molybdenum, tungsten, glassy carbon, carbon and silicon carbide.
Claim 17
Dependent Claim 13 words
An arc chamber according to claim 13 wherein said refractory material is tungsten.
Claim 18
Dependent Claim 16 words
An arc chamber according to claim 13 wherein the chamber walls are also made of tungsten.

References Cited (Backward Citations)

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US4135093A Cited
US4383177A Cited
US4447773A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1999-09-10 2000-03-11 2000-09-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2003-09-10 2004-03-11 2004-09-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2007-09-10 2008-03-11 2008-09-10 $7700.00 Window Closed / Lapsed

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