Ion implantation beam monitor
US6608316B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 2, 2001 |
| Grant date | Aug 19, 2003 |
| Priority date | — |
| Expiry date | Apr 2, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/31703
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An ion implanter, the total return current between the substrate holder and flight tube is measured. Measuring the total current returned to the flight tube provides a useful indication of the total ion current in the ion beam leaving the flight tube as well as any electrons travelling back to, and being absorbed by, the flight tube. This in turn permits the quality of the ion beam post mass selection to be monitored, continuously if desired. The total current returned to the flight tube can be compared with the current measured by the beam, the latter varying rapidly with time as the beam stop is periodically occluded by the rotating substrate wheel.In order to general a potential difference between the substrate holder and the flight tube, either a power supply or an active resistance such as an FET chain can be employed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.