Ion implantation having increased source lifetime

摘要

Ion implantation equipment is modified so as to provide filament reflectors to a filament inside of an arc chamber, and to remove the electrical insulators for the filament outside of the arc chamber and providing a shield, thereby reducing the formation of a conductive layer on said insulators and greatly extending the lifetime and reducing downtime of the equipment. The efficiency of the equipment is further enhanced by an interchangeable liner for the arc chamber that increases the wall temperature of the arc chamber and thus the electron temperature. The use of tungsten parts inside the arc chamber, obtained either by making the arc chamber itself or portions thereof of tungsten, particularly the front plate having the exit aperture for the ion beam, or by inserting a removable tungsten liner therein, decreases contamination of the ion beam. Serviceability of the arc chamber is improved by using a unitary clamp that separately grips both the filament and filament reflectors. This clamp can also advantageously be made of tungsten.