A new dose controller for the genus 1510/1520/Kestrel MeV ion implanters

A new Dose Controller has been developed for the Genus 1510/1520/Kestrel family of MeV Ion Implanters. The new Controller offers selectable scan times, permitting the end user to control the separation between adjacent beam passages across the wafer. Before every implant the total offset of the electronics, cabling and Faraday Cup is measured precisely. This value is then subtracted from the signal observed during the implant. Including the Faraday Cup in this measurement permits cancellation of any leakage currents that may be flowing in the Faraday circuit. The beam current is integrated only over the time that the disk slot is actually passing through the beam. Reducing the integration period further reduces the system's sensitivity to small offsets, and provides a consistent, minimum delay between the slot's passage and the availability of a new scan velocity.