Vacuum bearing structure and a method of supporting a movable member
US6515288B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 16, 2000 |
| Grant date | Feb 4, 2003 |
| Priority date | — |
| Expiry date | Mar 16, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/31701
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A vacuum bearing structure comprises a combination of a planar gas bearing with a differentially-pumped vacuum seal. The bearing surface and the vacuum seal surfaces are formed of a porous material divided into a first outer region through which bearing gas can percolate to provide support and an inner second region providing the vacuum seal. An exhaust groove separates the two regions so that bearing gas can flow to atmosphere. The resulting structure can operate at a lower fly height to reduce loading on the differentially-pumped vacuum seal. The structure is particularly useful for motion feedthroughs into vacuum processes such as ion implantation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.