Spiral magnetic linear translating mechanism

摘要

A spiral magnetic linear translating mechanism for use with a wafer processing system which includes a plurality of evacuatable housings connected in a series to form a processing line comprises at least one wafer support structure which is mounted to move on a track through the housings along the processing line. The structure includes a base disposed proximate a wall of the housing and includes a plurality of magnetic thread segments extending thereon to face the wall. Outside of the housing, a cylindrical shaft is mounted proximate the wall. An elongated magnetic drive with successive sections is wound spirally around the shaft to rotate with the shaft so that the sections of the drive face the wall opposite the thread segments. The magnetic thread segments are attracted to the magnetic drive, thus coupling the wafer support structure to the shaft such that when the shaft rotates the thread segments are exposed to different successive sections of the drive located further along the shaft and the wafer carrier is driven linearly along the track and through the housing. Preferably, the magnetic thread segments and spiral magnetic drive are made up of individual magnetic elements alternately magnetically polarized at their outer extremities with opposite magnetic polarities so that the individual thread segment elements are attracted to drive elements having opposite magnetic polarities. In an alternative embodiment, the shaft includes a plurality of magnetic drives wound spirally thereon. The shaft is covered with a non-magnetic sleeve to protect the magnetic drive.