EP0094473A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Apparatus and method for producing a stream of ions
Assignee: Kaufman Harold Richard
•
Filing: 1983-01-14
•
Granted: —
•
Expires: 2003-01-14
Abstract
Abstract A method and apparatus for generating high current, negative ion beams is described. A plasma source of ions of one charge polarity includes an accelerator for accelerating the ions toward a target having a plurality of apertures. An electric field directs the ions exiting the apertures against a target surface which is arranged to emit ions of an opposite polarity. The electric field directs the opposite polarity ions away from the target forming a stream of oppositely charged ions. In the drawing the ions produced in the plasma chamber 10 are accelerated toward the apertured grid 12 by field 8 and pass through the aligned apertures in the grid 12 and target 16. A field established between apertured grid 18 and target 16 reverses the general direction of the ion beams so that they bombard the back surface of the target. Ions of the opposite polarity are emitted from the back of the target and are accelerated away from the target by the field between the grid 18 and the target. The opposite polarity ions exit as streams through the apertures in the grid 18.
Inventors
- 👤 Jerome John Cuomo
- 👤 Harold Richard Kaufman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 19:39
CPC Classifications
H; H01; H01J; H01J27/00; H01J27/02; H01J27/20; H01J27/028
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
112 words
A method of producing a stream of ions of one polarity comprising generating a first stream of ions of the other polarity, bombarding a target formed of a suitable material with said other polarity ions to produce ions of said one polarity, and forming a second stream of said one polarity ions, characterised in that the first stream of ions initially passes through an aperture in the target and is thereafter subject to a first electric field which reverses the general direction of the first stream so that the ions thereof are incident on the back of the target and which accelerates the ions of said one polarity away from the target.
Claim 2
Independent Claim
112 words
A method of producing a stream of ions of one polarity comprising generating a first stream of ions of the other polarity, bombarding a target formed of a suitable material with said other polarity ions to produce ions of said one polarity, and forming a second stream of said one polarity ions, characterised in that the first stream of ions initially passes through an aperture in the target and is thereafter subject to a first electric field which reverses the general direction of the first stream so that the ions thereof are incident on the back of the target and which accelerates the ions of said one polarity away from the target.
Claim 3
Dependent Claim
46 words
A method as claimed in claim 1, further characterised by establishing the first electric field between the target and a first grid plate having at least one aperture therethrough so that the second stream of ions of the said one polarity is formed by the aperture.
Claim 4
Dependent Claim
66 words
A method as claimed in claim 1 or 2, further characterised by generating the ions of the other polarity in a plasma chamber and establishing a second electric field to accelerate the ions out of the plasma chamber towards an exit mask having at least one aperture therethrough so that the first stream of ions of the said other polarity is formed by the mask aperture.
Claim 5
Dependent Claim
156 words
Apparatus for carrying out a method as claimed in claim 1, 2 or 3, comprising means (10, 12) for generating a first stream of ions of the other polarity directed along a first path and a target (16) located along the first path and formed of a material capable of emitting ions of said one polarity when bombarded with ions of the other polarity, characterised in that the target (16) comprises an aperture (28) for the passage of the stream of ions of the other polarity through the target from one side to the other without being incident thereon and in that means (18) are provided for establishing an electric field adjacent the other side of the target capable of reversing the general direction of the first beam so that the ions thereof are incident on the other side of the target (16) and accelerating the ions of the said one polarity away from the target.
Claim 6
Dependent Claim
35 words
Apparatus as claimed in claim 4, further characterised in that said field establishing means comprise an apertured grid plate (18) and means for establishing a suitable potential difference between the grid plate and the target.
Claim 7
Dependent Claim
63 words
Apparatus as claimed in claim 4 or 5, further characterised in that said first ion stream generating means comprise a plasma chamber (10) in which an ionised plasma gas can be formed and means for establishing an electric gradient in the chamber for accelerating ions of a first polarity towards and through at least one stream-forming-exit-aperture (26) through the wall of the chamber.
Claim 8
Dependent Claim
207 words
Apparatus for generating a stream of charged ions comprising a plasma chamber (10) for receiving an ionizing gas and including an anode (14) and a cathode (16) between which an ionizinig current can be established to generate an ionised plasma in the chamber; a first apertured grid plate (12) located over an exit opening of said chamber and maintained at a potential to accelerating ions formed in said chamber along a trajectory path defined by the aperture in the grid plate; a target (16) located along said trajectory path, said target having an aperture (26) for passage of said ions and comprising a material having the property of emitting ions with a charge polarity opposite to the polarity of the incident ions; a second apertured grid plate (18) adjacent said target having at least one aperture (32) located in facing relation to an ion emitting surface of said target; and means for applying a voltage potential between said second grid plate (18) and said target (16) having a polarity for directing ions passing through said target aperture back against said target as they exit said target aperture and for accelerating oppositely charged ions emitted from said target material through the aperture(s) in said second grid plate (18).
Claim 9
Dependent Claim
207 words
Apparatus for generating a stream of charged ions comprising a plasma chamber (10) for receiving an ionizing gas and including an anode (14) and a cathode (16) between which an ionizinig current can be established to generate an ionised plasma in the chamber; a first apertured grid plate (12) located over an exit opening of said chamber and maintained at a potential to accelerating ions formed in said chamber along a trajectory path defined by the aperture in the grid plate; a target (16) located along said trajectory path, said target having an aperture (26) for passage of said ions and comprising a material having the property of emitting ions with a charge polarity opposite to the polarity of the incident ions; a second apertured grid plate (18) adjacent said target having at least one aperture (32) located in facing relation to an ion emitting surface of said target; and means for applying a voltage potential between said second grid plate (18) and said target (16) having a polarity for directing ions passing through said target aperture back against said target as they exit said target aperture and for accelerating oppositely charged ions emitted from said target material through the aperture(s) in said second grid plate (18).
Claim 10
Dependent Claim
28 words
Apparatus as claimed in claim 7, further characterised in that said target is shaped to direct said emitted ions through the apertures in said second grid plate (18).
Claim 11
Dependent Claim
29 words
Apparatus as claimed in claim 7 or 8, further characterised in that said target apertures are smaller in diameter than said apertures (26) in the first grid plate (12).
Claim 12
Dependent Claim
41 words
Apparatus as claimed in claim 7, 8 or 9, further characterised in that the differences in the voltage potential between said first grid plate and the target is less than the potential difference between said second grid plate and the target.
Claim 13
Dependent Claim
23 words
Apparatus as claimed in any one of claims 7 to 10, further characterised in that said target material comprises samarium gold alloy (SMAU).
Claim 14
Independent Claim
197 words
An apparatus for generating negative ions comprising: a plasma generator comprising a chamber receiving a gas for ionization, an electron emitter and anode connected to ionize said gas whereby a plasma bordered by a plasma sheath is produced, said chamber having an exit port bounded by an exit grid having a voltage potential for accelerating positive ions in said chamber through said grid, said plasma generator further including a magnetic field for constraining energetic electrons generated in the plasma; a target having a plurality of apertures for passing ions emitted by said grid, said target having a surface on the exit side of said target apertures for emitting negative ions along a predetermined trajectory in response to bombardment by positive ions exiting said target apertures; a second grid for receiving ions emitted by said target surface; and means for applying between said target surface and second grid a voltage potential for establishing a field for reversing the direction of travel of said positive ions exiting said target apertures whereby collisions with said emitting surface occur to produce negative ions that are swept by said field through said second grid thereby to form a stream of negative ions.
Claim 15
Independent Claim
197 words
An apparatus for generating negative ions comprising: a plasma generator comprising a chamber receiving a gas for ionization, an electron emitter and anode connected to ionize said gas whereby a plasma bordered by a plasma sheath is produced, said chamber having an exit port bounded by an exit grid having a voltage potential for accelerating positive ions in said chamber through said grid, said plasma generator further including a magnetic field for constraining energetic electrons generated in the plasma; a target having a plurality of apertures for passing ions emitted by said grid, said target having a surface on the exit side of said target apertures for emitting negative ions along a predetermined trajectory in response to bombardment by positive ions exiting said target apertures; a second grid for receiving ions emitted by said target surface; and means for applying between said target surface and second grid a voltage potential for establishing a field for reversing the direction of travel of said positive ions exiting said target apertures whereby collisions with said emitting surface occur to produce negative ions that are swept by said field through said second grid thereby to form a stream of negative ions.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.