A method and apparatus for dosage measurement and monitoring in an ion implantation system is disclosed. In one embodiment, a transferring system, includes: a vacuum chamber, wherein the vacuum chamber is coupled to a processing chamber; a shaft coupled to a ball screw, wherein the ball screw and the shaft are configured in the vacuum chamber; and a vacuum rotary feedthrough, wherein the vacuum rotary feedthrough comprises a magnetic fluid seal so as to provide a high vacuum sealing, and wherein the vacuum rotary feedthrough is configured through a first end of the vacuum chamber and coupled to the ball screw so as to provide a rotary motion on the ball screw.