Claims
- 1. A method of removing neutral noise from an ion beam, comprising:(a) transmitting an ion beam having a lobed cross-sectional shape; and (b) filtering said ion beam with a mask plate that has a lobed aperture.
- 2. A method of removing neutral noise from an ion beam, as recited in claim 1, wherein said lobed aperture has a shape substantially similar to the cross-sectional area of the ion beam.
- 3. A mask plate having an aperture shaped for removing neutral noise from an ion beam that is directed along a longitudinal axis through said aperture, said aperture comprising:(a) a central portion at said axis; and (b) at least one lobe contiguous with said primary portion and extending radially from said longitudinal axis.
- 4. The mask plate as recited in claim 3, wherein said lobe is a first lobe and said aperture further comprises a second lobe extending radially from said longitudinal axis in an opposite direction from said first lobe.
- 5. The mask plate as recited in claim 4, wherein said aperture comprises third and fourth lobes extending radially from said longitudinal axis and symmetrically positioned with respect to said first and second lobes.
Parent Case Info
This is a continuation of application Ser. No. 09/655,758, filed on Sep. 6, 2000, now U.S. Pat. No. 6,545,271, the entire disclosure of which is incorporated herein by reference.
US Referenced Citations (7)
Continuations (1)
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Number |
Date |
Country |
Parent |
09/655758 |
Sep 2000 |
US |
Child |
10/293118 |
|
US |