Multipole implantation-isotope separation ion beam source
US4383177A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 24, 1980 |
| Grant date | May 10, 1983 |
| Priority date | — |
| Expiry date | Dec 24, 2000 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/08
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A plurality of magnetic pole pieces are arranged around the external wall of a high temperature plasma confining structure. The pole pieces are positioned between permanent magnets spaced from one another and the confining structure by distances calculated to produce a minimum field toward the center of the structure with an effective containing field around the periphery of the structure. The magnets and the pole pieces are cooled. An odd number of poles are employed such that the missing pole appears as a virtual pole at the extraction slit used for forming an ion beam for ion implantation. The resulting small package multipole plasma containment functions to provide higher beam current, longer source lifetime, higher voltage stability and reduces maintenance and cleaning operations, with the permanent magnets protected from high temperature and corrosive gases.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.