Workpiece mounting and clamping system having submicron positioning repeatability
US4642438A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 1984 |
| Grant date | Feb 10, 1987 |
| Priority date | — |
| Expiry date | Nov 19, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/20
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A high precision, high throughput submicrometer workpiece positioning system, particularly useful as a workpiece positioning means in electron beam lithography tools. The positioning system increases mechanical stability by essentially eliminating mechanical hysteresis, which allows state of the art electron beam lithography systems to provide the repeatable, accurate and dense circuit patterns that modern semiconductor trends demand. The positioning system in preferred form comprises a movable positioning table, a workpiece supporting superstructure which is elastically joined to the movable positioning table by three geometrically distinct kinematic support means and a two-stage coupling means which mounts a workpiece (i.e., semiconductor mask or wafer) to the workpiece supporting superstructure. A laser interferometer locating-positioning system is utilized to position the workpiece. The interferometer mirrors are integral with the workpiece supporting superstructure. The coupling means mounts a workpiece to the workpiece supporting superstructure with a minimum of mechanical distortion. Three two-stage coupling means are utilized in preferred form. The first stage is removable …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.