Patent Number: 048312703
Section: abstract

An ion implantation system includes an ion source generating a horizontally directed ion beam. A quadrupole shapes the beam and a pair of deflector plates deflect the beam downwardly to wafers disposed on a horizontally disposed wheel. The beam is shifted radially relative to the wheel by a deflector plate carrier apparatus. This apparatus includes a stepper motor controlled driver magnet disposed externally of a beam/wheel evacuated enclosure. A driven magnet disposed in the enclosure is joined to the deflector plates all of which ride on linear bearings. Movement of the driving magnet moves the driven magnet, and therefore, the deflector plates and beam. An evacuatable transport is used to transport wafers in cassettes on or wafer mounting plates in a vacuum. A robot arm in the wheel enclosure retrieves wafers from a cassette in the transporter through adjoining sealable ports for placement on and removal from wafer support plates on the wheel. Alternatively, two independently rotatable wheels may be provided with beam impingement regions of both accessible from above. One wheel may then be loaded and unloaded while wafers on the other are being implanted.