Charging control on high energy implanters: A process requirement demonstrated by plasma damage monitoring

Charging phenomena is one of the main problems faced in ion implantation. Anti-charging system such as plasma flood gun (PFG) are currently running on high current and medium current implanters to reduce potential charging damage on device structures. However, in a conventional production line, high energy implantation steps are still often used without any charge compensation technique. Faced with micro-arcing defects detected after Well implantation steps on production lots, we have clearly demonstrated that the defectivity issue was eradicated by enabling the PFG system on the VIISta3000 high energy implanter. In addition we have investigated charging as a function of PFG properties by plasma damage monitoring (PDM) and proved that voltages developed on oxidized wafers processed on the VIISta3000 were not insignificant.