Applied Materials, Inc.

Christopher Burgess

Richard David Goldberg

David George Armour

Adrian John Murrell

Andrew S Devaney

Richard D Goldberg

David Kirkwood

Martin Keane

The present invention relates to ion sources () comprising a cathode () and a counter-cathode () that are suitable for ion implanters (). Typically, the ion source is held under vacuum and produces ions using a plasma generated within an arc chamber (). Plasma ions are extracted from the arc chamber and subsequently implanted in a semiconductor wafer (). The ion source according to the present invention further comprises a cathode () arranged to emit electrons into the arc chamber; an electrode () positioned in the arc chamber such that electrons emitted by the cathode are incident thereon; one or more voltage potential sources () arranged to bias the electrode; and a voltage potential adjuster () operable to switch between the voltage potential source biasing the electrode positively thereby to act as an anode and the voltage potential source biasing the electrode negatively thereby to act as a counter-cathode.

Cathode and counter-cathode arrangement in an ion source

The present invention relates to a front plate for an ion source that is suitable for an ion implanter. The front plate according to the invention comprises obverse and reverse sides, an exit aperture for allowing egress of ions from the ion source that extends substantially straight through the front plate between the obverse and reverse sides, and a slot penetrating through the front plate from obverse side to reverse side at a slant for at least part of its depth, the slot extending from a side of the front plate to join the exit aperture. The slot is slanted to occlude line of sight into the ion source when viewed from in front, yet provides an expansion gap.

Front plate for an ion source

A method of tuning an ion beam in an ion implanter relative to, e.g., ion beam current, energy, size and shape, includes retrieving a set of parameters associated with operation of the ion implanter, at least some of which are stored in a dynamic database, configuring the ion implanter according to the retrieved set of parameters, to thereby provide an ion beam, optimizing the ion beam by varying one or more of the parameters, and updating the parameters stored in the dynamic database which changed during optimization.

Ion beams in an ion implanter

Provided is an ion implanter having a deceleration lens assembly comprising a plurality of electrodes in which one or more of the apertures of the deceleration electrodes are shaped in a manner which can improve performance of the ion implanter. In one embodiment, an electrode aperture is generally elliptical in shape and conforms generally to the shape of the beam passing through the aperture. In another aspect, an axis segment extends 40% of the length of the aperture from the aperture center to an intermediate point at the end of the segment. The average width of the aperture measured at each point from the center to the intermediate point is substantially less than the maximum width of the aperture.

Ion implanter electrodes

G electrode is mounted so as to be movable along the beam line and, optionally, perpendicular to it as well. G and G are curved with a constant gap between G and G in the radial direction (so that the two electrodes are concentric). This contrasts with the prior art where G and G were equidistantly spaced along the beam line direction instead. G is made re-entrant adjacent the slit so as to improve extraction efficiency from the plasma. Finally, a lens such as a quadrupole lens is formed downstream of G

Growing community of inventors

East Sussex, United Kingdom

Christopher Burgess