Patent ID: 7915597
Filing Date: 2011-03-29
Classification: H01J

Abstract:
1. A variable aperture electrode apparatus, comprising: an ion source comprising an extraction electrode, wherein the extraction electrode generally defines an extraction aperture in an outside wall of the ion source, and wherein the extraction electrode is configured to extract ions from the ion source, therein defining an ion beam; a suppression electrode positioned downstream of the extraction electrode, wherein the suppression electrode comprises first and second suppression electrode plate disk halves defining a variable suppression aperture therebetween, and wherein a gap is defined along a path of the ion beam between the extraction aperture and suppression aperture; a ground electrode positioned downstream of the suppression electrode by a predetermined distance along the path of the ion beam, wherein the ground electrode comprises first and second ground electrode plate disk halves defining a variable ground aperture therebetween; and a moving mechanism configured to concurrently translate the suppression electrode and ground electrode along the path of the ion beam along a first axis, wherein the gap between the extraction aperture and suppression aperture is variable based on the translation along the first axis, and wherein the moving mechanism is further configured to translate the first and second suppression electrode plate disk halves with respect to one another and to translate the first and second ground electrode plate disk halves with respect to one another, wherein the translation of the first and second suppression electrode plate disk halves and first and second ground electrode disk plate halves is parallel to a second axis generally perpendicular to the first axis.