Abstract: A system for removal of contaminating particles from a target chamber (1) which includes a target chamber having an aperture in the floor thereof for entry of a reciprocating shaft (7) for positioning a wafer (11) within the target chamber, a seal (21) disposed at the aperture and about the shaft to seal-the interior of the target chamber from the exterior of the target chamber at the seal and a removable shield mechanism (17), preferably of polytetrafluoroethylene, disposed within the target chamber, above the seal and around the shaft to retain particles scraped from the shaft. The shield mechanism has a pocket (29) disposed over the seal and around the shaft to retain the particles therein isolated from the target chamber. The shield mechanism comprises a shield (17) disposed around the shaft and a collar (18) contacting the shield and the floor of the target chamber to form the pocket with the seal. The collar further includes a lip (16) extending toward the shaft for supporting the shield thereon.

Abstract: A system for removal of contaminating particles from a target chamber (1) which comprises the target chamber having an aperture (3) for entry of an ion beam (2) therein, an orienting device (7, 9, 13, 15) within the target chamber for orienting a wafer (11) with respect to the ion beam and a reusable, removable shield (23), preferably of stainless steel, disposed along the interior walls of the target chamber and secured to the interior walls. A securing device (24) is provided for releasably securing the shield to the interior walls of the target chamber.