Plasma electron flood for a scanned beam implanter

Recently, charging damage has been observed even in relatively low dose implantation on medium current ion implanters, especially in the case of wafers coated with photoresist patterns. To suppress the charging damage in implantation, a plasma electron flood system has been developed for the medium current ion implanter, NV-MC3, which has an electrostatic beam scanning system and accommodates up to 300mm wafers. The plasma electron flood system has a large size chamber with multi-cusp magnetic fields and supplies electrons for the scanned beam from a long slit to the whole scanning region. An in-situ charge detection system has been also developed to monitor the performance of the flood system. The evaluation results of these systems will be reported below.