Universal edged-based wafer alignment apparatus
US4907035A · kind A · utility
40Cited by
8References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 21, 1986 |
| Grant date | Mar 6, 1990 |
| Priority date | — |
| Expiry date | Mar 21, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/70
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An apparatus for aligning a wafer. The edge of a wafer is mapped by means of a photodetector array and a light source to provide a signal representative of the X-Y position and angular orientation of the wafer as the wafer is rotated one revolution on a shaft. The signal is digitized and processed to provide stored information of the X-Y position and angular orientation of the wafer. The shaft is then rotated to move the wafer from its calculated angular orientation to a desired angular orientation. The X-Y positional information may be used to center the wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.