摘要 |
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.
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