Mechanism for preventing metallic ion contamination of a wafer in ion implantation equipment

摘要

When employing conventional ion implantation equipment, the peripheral edge of the wafer is contaminated by metallic ions generated from the collision of the accelerated ion beam with the disk that supports the target, namely a wafer. The present invention provides a magnet for forming a magnetic field which will repel the generated metallic ions. The magnet is disposed on the disk and surrounds the wafer to prevent the metallic ions from impinging the wafer.