Determining beam alignment in ion implantation using Rutherford Back Scattering
US6555832B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 12, 2000 |
| Grant date | Apr 29, 2003 |
| Priority date | — |
| Expiry date | Apr 29, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/1501
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A back scattered ion receiver is mounted on the process chamber of an ion implanter to receive beam ions back scattered from a wafer mounted on the wafer holder in the chamber. Minima in the intensity of back scattered ions as the wafer on the holder is moved relative to the beam direction, can be used to obtain an accurate calibration of the true beam direction. Beam direction error can then be compensated for when operating holder tilt and twist mechanisms so as to bring a process wafer accurately into the required orientation relative to the true beam. If the crystallographic alignment and orientation of process wafers has been precharacterised, this data can be used to control the wafer holder to align process wafers crystallographically to the process beam.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.