Z-axis monitoring apparatus for robot blade
US6727994B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 2002 |
| Grant date | Apr 27, 2004 |
| Priority date | — |
| Expiry date | Jun 26, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/14
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus for monitoring the Z-axis position of a transfer blade on a wafer transfer robot which transfers wafers among multiple chambers in a semiconductor fabrication facility. The invention comprises a CCD laser displacement sensor which measures the height or Z-axis position of the transfer blade and generates an analog voltage the value of which depends on the height of the transfer blade. An analog controller connected to the CCD laser displacement sensor converts the analog voltage signal to physical distance, which may be displayed on an LCD display on the analog controller. The analog controller may further be connected to a robot controller through an interface PCB, in which case a voltage signal corresponding to an abnormal position of the transfer blade is transmitted to the robot controller and the wafer transfer operation is terminated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.