Performance of a plasma flood gun in the medium current ion implanter Exceed200OA

Device charging problems arise in medium-current ion implantation processes due to the very thin gate oxide thickness and large photo-resist coverage ratio. To compensate the ion beam charge-up a PFG for the hybrid scanning medium current ion implanter Exceed2000A was developed which didn't degrade the dose uniformity (<0.5%), dose shift (<2%), and a metal contamination under a condition with a clamp-less electrostatic chuck. The characteristics of this PFG is evaluated by MOS Capacitor TEG, floating electrode charge sensor and Charm2 wafer, which show good charge compensation performances. The small flow rate of the PFG gas makes it possible to apply a PFG to the medium current ion implanter.