Semiconductor fabricating apparatus having vacuum control and detection system
US5769948A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 10, 1997 |
| Grant date | Jun 23, 1998 |
| Priority date | — |
| Expiry date | Jun 10, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/6715
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A vacuum control and detection system for a semiconductor fabricating apparatus includes a vacuum line connected to a plate for holding a semiconductor wafer to be processed. An electromagnetic valve is connected to the vacuum line for selectively opening and closing the vacuum line. A control unit receives a wafer sensing signal from the plate, and supplies an actuating voltage to the electromagnetic valve to open the vacuum line and securely hold the wafer to the plate via a vacuum force. A time delay device also receives the actuating voltage from the control unit and outputs a wafer holding signal to the control unit after a 2-3 second time delay. After wafer processing operations are completed, the control unit deactivates the actuating voltage supplied to the electromagnetic valve and the time delay device to close the vacuum line and release the vacuum force on the wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.