Ion source having wide output current operating range
First Claim
1. An attenuator (90) for an ion source (26), the ion source comprising a plasma chamber (76) in which a gas is ionized by an exciter (78) to create a plasma which is extractable through at least one aperture (64) in an aperture plate (50) of said chamber to form an ion beam, said attenuator (90) comprising:
- a member (90) positioned within said chamber (76) intermediate said exciter (78) and said at least one aperture (64), said member providing at least one first opening (97) corresponding said at least one aperture (64), said member being moveable between first and second positions with respect to said at least one aperture, wherein said member and said aperture plate form a generally closed region (102) therebetween when said member is in said first position, and wherein said aperture (64) is in direct communication with said chamber (76) when said member is in said second position, such that in said first position plasma within said chamber (76) diffuses through said region (102) and is extracted through said aperture and in said second position plasma within said chamber is extracted directly through said aperture.
3 Assignments
0 Petitions
Accused Products
Abstract
An attenuator (90) for an ion source (26) is provided. The ion source comprises a plasma chamber (76) in which a gas is ionized by an exciter (78) to create a plasma which is extractable through at least one aperture (64) in an apertured portion (50) of the chamber to form an ion beam. The attenuator (90) comprises a member (90) positioned within the chamber (76) intermediate the exciter (78) and the at least one aperture (64), the member providing at least one first opening (97) corresponding the at least one aperture (64), and being moveable between first and second positions with respect to the at least one aperture. In one embodiment, in the first position, the member is positioned adjacent the aperture (64) to obstruct at least a portion of the aperture, and in the second position the member is positioned away from the aperture (64) so as not to obstruct the aperture. In a second embodiment, the aperture (64) resides in an aperture plate (50) and (i) the member and the aperture plate form a generally closed region (102) between the aperture plate and the chamber (76) when the member is in the first position, and (ii) the aperture (64) is in direct communication with the chamber (76) when the member is in the second position. In this second embodiment, plasma within the chamber (76) diffuses through the region (102) before being extracted through the aperture in the first position, and plasma within the chamber is extracted directly through the aperture in the second position.
38 Citations
18 Claims
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1. An attenuator (90) for an ion source (26), the ion source comprising a plasma chamber (76) in which a gas is ionized by an exciter (78) to create a plasma which is extractable through at least one aperture (64) in an aperture plate (50) of said chamber to form an ion beam, said attenuator (90) comprising:
a member (90) positioned within said chamber (76) intermediate said exciter (78) and said at least one aperture (64), said member providing at least one first opening (97) corresponding said at least one aperture (64), said member being moveable between first and second positions with respect to said at least one aperture, wherein said member and said aperture plate form a generally closed region (102) therebetween when said member is in said first position, and wherein said aperture (64) is in direct communication with said chamber (76) when said member is in said second position, such that in said first position plasma within said chamber (76) diffuses through said region (102) and is extracted through said aperture and in said second position plasma within said chamber is extracted directly through said aperture. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. An ion source (26), comprising:
a plasma chamber (76) in which a gas is ionized by an exciter (78) to create a plasma which is extractable through at least one aperture (64) in an aperture plate (50) of said chamber to form an ion beam, said attenuator (90) comprising; a member (90) positioned within said chamber (76) intermediate said exciter (78) and said at least one aperture (64), said member providing at least one first opening (97) corresponding said at least one aperture (64), said member being moveable between first and second positions with respect to said at least one aperture, wherein said member and said aperture plate form a generally closed region (102) therebetween when said member is in said first position, and wherein said aperture (64) is in direct communication with said chamber when said member is in said second position, such that in said first position plasma within said chamber (76) diffuses through said region (102) and is extracted through said aperture and in said second position plasma within said chamber is extracted directly through said aperture. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18)
Specification