A duopigatron ion source is modified by replacing the normal oxide-coated wire filament cathode of the ion source with a hot tungsten oven through which hydrogen gas is fed into the arc chamber. The hydrogen gas is predissociated in the hot oven prior to the arc discharge, and the recombination rate is minimized by hot walls inside of the arc chamber. With the use of the above modifications, the atomic H.sub.1.sup.+ ion fraction output can be increased from the normal 50% to greater than 70% with a corresponding decrease in the H.sub.2.sup.+ and H.sub.3.sup.+ molecular ion fraction outputs from the ion source.
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 means of shielding, 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 means of 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 means of a unitary clamp that separately grips both the filament and filament reflectors. This clamp can also advantageously be made of tungsten.
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 means of shielding, 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 means of 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 means of a unitary clamp that separately grips both the filament and filament reflectors. This clamp can also advantageously be made of tungsten.
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.
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 means of shielding, 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 means of 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 means of a unitary clamp that separately grips both the filament and filament reflectors. This clamp can also advantageously be made of tungsten.
An ion source for ion implantation system and a method of ion implantation employs a controlled broad, directional electron beam to ionize process gas or vapor, such as decaborane, within an ionization volume by primary electron impact, in CMOS manufacturing and the like. Isolation of the electron gun for producing the energetic electron beam and of the beam dump to which the energetic beam is directed, as well as use of the thermally conductive members for cooling the ionization chamber and the vaporizer, enable use with large molecular species such as decaborane, and other materials which are unstable with temperature. Electron optics systems, facilitate focusing of electrons from an emitting surface to effectively ionize a desired volume of the gas or vapor that is located adjacent the extraction aperture. The components enable retrofit into ion implanters that have used other types of ion sources. Demountable vaporizers, and numerous other important features, realize economies in construction and operation. Achievement of production-worthy operation in respect of very shallow implants is realized.
