Refurbishment of epoxy accelerator column bushings

This paper describes a new cleaning process developed for the refurbishment of the large epoxy bushings used as high voltage insulators in the source and accelerator columns of ion implant tools. The process is designed to remove arsenic compounds condensed on the internal surfaces of these bushing as well as scattered ions implanted into the near surface region of the epoxy. In order to remove the implanted ions, some epoxy resin on the surface of the bushing must also be stripped away. Lead oxide particles exposed on the surface as a result of the removal of this epoxy are extracted in the final step of the cleaning process. Data is presented characterizing the surface contamination found on a Varian E1000 accelerator column bushing from an arsenic implant tool. The morphology and composition of the internal surfaces of this bushing are compared before and after refurbishment.