Vacuum attraction type substrate holding device
US5203547A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 27, 1991 |
| Grant date | Apr 20, 1993 |
| Priority date | — |
| Expiry date | Nov 27, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/6838
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A vacuum attraction type substrate holding system includes a vacuum source; a distributor for distributing a vacuum from the vacuum source into plural vacuum lines; a plurality of vacuum attraction type substrate holding portions corresponding to the vacuum lines, respectively, each of the substrate holding portions having a valve which is openable and closable for control of the supply of vacuum to the corresponding substrate holding portions, wherein the opening or closing of each valve is influential to control attraction or release of a substrate to or from a corresponding substrate holding portion; and a plurality of restriction valves each being disposed between the distributor and corresponding one of the valves, for serving as a resistance to a gas flowing from the corresponding valve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.