Hani Elsayed-Ali

Abstract:

Ion deposition and implantation are key steps in microelectronic and nanofabrication. Yet, at the present time, almost all industrial ion processing is based on the use of singly charged ions. Recent technological advancements have demonstrated the effectiveness of the use of multicharged ions (MCIs) for deposition and implantation. MCIs carry substantial potential energy, which, depending on the ion charge state, can be considerably more than its kinetic energy. The MCI interaction with the solid involves the release of this potential energy in addition to its kinetic energy. Ultraslow highly charged ions deposit significant energy at an atomic layer scale causing surface processes not possible with singly-charged ions. MCIs have applications in areas beyond nanotechnology. These include highly sensitive secondary ion mass spectrometry for chemical analysis, and applications in biomedicine ranging from generation of monoenergetic x-rays for diagnostic imaging to the generation of highly charged carbon ions for cancer therapy. The availability of commercial MCI sources would expand applications of MCIs in diverse areas. Most of the installed MCI instruments are of the electron cyclotron resonance ion source (ECRIS) and electron beam ion source (EBIS) type and are in Europe, Japan and the USA. Laser MCI sources are becoming more accepted as potential ion sources for implantation and deposition. MCI technology and its applications will be reviewed with emphasis on newly developed laser MCI sources.