Semiconductor processing workpiece support with sensory subsystem for detection of wafers or other semiconductor workpieces
US6004828A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 30, 1997 |
| Grant date | Dec 21, 1999 |
| Priority date | — |
| Expiry date | Sep 30, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/681
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A semiconductor processing workpiece support which includes a detection subsystem that detects whether a wafer or other workpiece is present. The preferred arrangement uses an optical beam emitter and an optical beam detector mounted along the back side of a rotor which acts as a workpiece holder. The emitted beam passes through the workpiece holder and is reflected by any workpiece present in the workpiece holder. The preferred units include both an optical emitter and pair of detectors. The detection is preferably able to discriminate on the basis of the angle of the reflected beam, so that a portion of the beam reflected by the workpiece holder is not considered or minimized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.