Varian Semiconductor Equipment Associates, Inc.

Peter E Maciejowski

Bjorn O Pedersen

Joseph C Olson

Paul J Murphy

Shengwu Chang

Leo Klos

Daniel Distaso

Charles M McKenna

Curt D Bergeron

William G Goodenough

An indirectly heated cathode ion source includes an arc chamber housing that defines an arc chamber, an indirectly heated cathode and a filament for heating the cathode. The cathode may include an emitting portion having a front surface, a rear surface and a periphery, a support rod attached to the rear surface of the emitting portion, and a skirt extending from the periphery of the emitting portion. A cathode assembly may include the cathode, a filament and a clamp assembly for mounting the cathode and the filament in a fixed spatial relationship and for conducting electrical energy to the cathode and the filament. The filament is positioned in a cavity defined by the emitting portion and the skirt of the cathode. The ion source may include a shield for inhibiting escape of electrons and plasma from a region outside the arc chamber in proximity to the filament and the cathode.

Indirectly heated cathode ion source

Methods and apparatus are provided for efficiently operating an ion implanter which includes a charged particle accelerator in a high energy mode and in a low energy mode. The charged particle accelerator includes a high voltage power supply, an accelerator column coupled to the high voltage power supply and a switching assembly. The accelerator column includes a plurality of accelerator electrodes. The high voltage power supply is disabled from energizing the accelerator column in the low energy mode. The switching assembly includes switching elements for electrically connecting the accelerator electrodes to a reference potential in the low energy mode and for electrically isolating the accelerator electrodes from the reference potential in the high energy mode. The switching assembly prevents positive potentials on the accelerator electrodes and thus minimizes space charge expansion of the beam when transporting positive ion beams in the low energy mode.

Methods and apparatus for operating high energy accelerator in low energy mode

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Amesbury, MA, United States of America

Peter E Maciejowski