Potential applications of fusion neutral beam facilities for advanced material processing

摘要

Surface processing techniques involving high energy ion implantation have achieved commercial success for semiconductors and biomaterials. However, wider use has been limited in good part by economic factors, some of which are related to the line-of-sight nature of the beam implantation process. Plasma source ion implantation is intended to remove some of the limitations imposed by directionality of beam systems and also to help provide economies of scale. The present paper will outline relevant technologies and areas of expertise that exist at Oak Ridge National Laboratory in relation to possible future needs in materials processing. Experience in generation of plasmas, control of ionization states, pulsed extraction, and sheath physics exists. Contributions to future technology can be made either for the immersion mode or for the extracted beam mode. Existing facilities include the High Power Test Facility, which could conservatively operate at 1 A of continuous current at 100 kV delivered to areas of about 1 m(sup 2). Higher instantaneous voltages and currents are available with a reduced duty cycle. Another facility, the High Heat Flux Facility can supply a maximum of 60 kV and currents of up to 60 A for 2 s on a 10% duty cycle. Plasmas may be generated by use of microwaves, radio-frequency induction or other methods and plasma properties may be tailored to suit specific needs. In addition to ion implantation of large steel components, foreseeable applications include ion implantation of polymers, ion implantation of Ti alloys, Al alloys, or other reactive surfaces.