Treating workpieces with beams
US4234797A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 23, 1979 |
| Grant date | Nov 18, 1980 |
| Priority date | — |
| Expiry date | May 23, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/3171
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In apparatus for controlling the treatment of a workpiece by a beam emanating from a source, there is translational relative movement in two orthogonal directions between the beam and the workpiece support element, and control of velocity in one (control) direction occurs in response to a detector, mounted behind the support, which periodically samples the beam through a moving slot in the support element. This slot extends over the range of movement in the control direction. An ion implanter is shown in which the support element is a constantly spinning disk the axis of which is translated in the control direction. Another ion implanter is shown in which the support element is a moving belt. A simple control circuit, useful for both embodiments, achieves a uniform ion dosage upon semiconductor substrates at a high production rate despite variations in beam intensity. The detector is not affected by a shower of electrons upon the support that neutralizes charge on the workpieces.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.