Abstract: A system and method for controlling an ion implantation system as a function of sampling ion beam current and uniformity thereof. The ion implantation system includes a plurality of ion beam optical elements configured to selectively steer and/or shape the ion beam as it is transported toward a workpiece, wherein the ion beam is sampled at a high frequency to provide a plurality of ion beam current samples, which are then analyzed to detect fluctuations and/or nonuniformities or unpredicted variations amongst the plurality of ion beam current samples. Beam current samples are compared against predetermined threshold levels, and/or predicted nonuniformity levels to generate a control signal when a detected nonuniformity in the plurality of ion beam current density samples exceeds a predetermined threshold.

Abstract: A system and method for controlling an ion implantation system as a function of sampling ion beam current and uniformity thereof. The ion implantation system includes a plurality of ion beam optical elements configured to selectively steer and/or shape the ion beam as it is transported toward a workpiece, wherein the ion beam is sampled at a high frequency to provide a plurality of ion beam current samples, which are then analyzed to detect fluctuations and/or nonuniformities or unpredicted variations amongst the plurality of ion beam current samples. Beam current samples are compared against predetermined threshold levels, and/or predicted nonuniformity levels to generate a control signal when a detected nonuniformity in the plurality of ion beam current density samples exceeds a predetermined threshold.

Abstract: An ion implanter includes an dosage control apparatus for measuring and controlling ion beam dosage applied to workpieces disposed in an implantation station of the implanter. The dosage control apparatus permits the direct calculation of a calibration function. The calibration function includes at least one calibration factor, called a K value. The K value is used by dosage control circuitry of the dosage control apparatus to convert from a measured ionized beam current, I.sup.f, as measured by a Faraday cage disposed in the implantation station, to a true or effective beam current, I.sup.T. The K value is determined from a relationship between the measured ionized beam current, I.sup.+, and a pressure, P, in the implantation station. The relationship between the effective beam current, I.sup.T, the measured ionized beam current, I.sup.f, and the implantation station pressure, P, will normally take the form of an exponential relationship, e.g., I.sup.T =I.sup.f [e.sup.-(KP) ].