Wafer positioning device
US6471464B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 8, 1999 |
| Grant date | Oct 29, 2002 |
| Priority date | — |
| Expiry date | Oct 8, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S414/136
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A device for orienting and/or centering a wafer is provided. The device employs a CCD camera and backlighting source which enhances the CCD camera's ability to detect wafer position. The backlighting source may be positioned along the side of the wafer opposite the CCD camera, or may be positioned adjacent the CCD camera. When positioned adjacent the CCD camera one or more shields are employed to prevent direct or reflected light from impacting the top surface of the wafer being detected by the CCD camera. Accordingly the only light detected by the CCD camera is light which passes the wafer and reflects from a surface therebeyond, back to the CCD camera, resulting in effective backlighting of the wafer. The image of the wafer may be further sharpened by roughening the surface from which light reflects back to CCD camera.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.