Patent ID: 6894296

Claim:
A method of prolonging a lifetime of a filament in a plasma flood system for an ion implanter during a plasma flood operation, said method comprising: providing a generally cylindrical arc chamber comprising a sleeve having a gas entry opening, a qenerally cylindrical chamber wall defining a chamber interior provided in said sleeve and a gas flow annulus defined between said sleeve and said chamber wall; providing a plurality of gas inlet opening in said chamber wall in spaced-apart relationship to each other along at least a portion of a circumference of said chamber wall and in fluid communication with said gas flow annulus; positioning the filament in said chamber interior; transmitting a current through said filament; and introducing a plasma-forming gas into said plurality of gas inlet openings through said gas entry opening and said gas flow annulus at a gas flow rate of at least about 0.5 sccm, whereby said gas travels in a substantially turbulent path in said chamber interior and contacts said filament at multiple points of contact on said filament.