Cathode assembly for indirectly heated cathode ion source
AssigneeVarian Semiconductor Equipment Associates, Inc.
InventorsJoseph C. Olson, Leo Klos, Anthony Renau, Nicholas A. Venuto
Life of this patent
Estimating the term…
Abstract
A cathode in an indirectly heated cathode ion source is supported by at least one rod or pin. The cathode is preferably in the form of a disk, and the support rod is smaller in diameter than the disk to limit thermal conduction and radiation. In one embodiment, the cathode is supported by a single rod at or near its center. The support rod may be held by a spring-action clamp for simple and reliable clamping and unclamping. The disk shaped cathode and the support rod may be fabricated as a single piece. A filament that emits electrons thermionically may be disposed around the rod in close proximity to the cathode.
Claims18
A cathode sub-assembly for an ion source comprising:
- an indirectly heated cathode;
- and
- a support rod fixedly attached to the indirectly heated cathode for supporting the cathode within an arc chamber of the ion source.
A cathode assembly for use in an indirectly heated cathode ion source which includes an arc chamber housing that defines an arc chamber, comprising:
- a cathode sub-assembly, including a cathode and a support rod fixedly mounted thereto;
- and
- a filament for emitting electrons, that is positioned outside the arc chamber in close proximity to the support rod of the cathode sub-assembly;
- and
- a cathode insulator for electrically and thermally isolating the cathode from an arc chamber housing, that is disposed around the cathode of the cathode sub-assembly.
A method for supporting and indirectly heating a cathode of an ion source comprising steps of:
- supporting the cathode by a rod fixedly attached to the cathode;
- and
- bombarding the cathode with electrons.
A cathode assembly for an ion source comprising:
- a cathode;
- a support rod fixedly attached to the cathode;
- and
- a cathode insulator for electrically and thermally isolating the cathode from an arc chamber housing;
- and
- an indirect heating means for indirectly heating the cathode.
Dependencies are inferred from the claim text.