Lithographic device with a three-dimensionally positionable mask holder
US5767948A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 2, 1996 |
| Grant date | Jun 16, 1998 |
| Priority date | — |
| Expiry date | May 2, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70833
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A lithographic device includes a machine frame which supports a substrate holder, a focusing system and a mask holder in a vertical direction. The substrate holder is displaceable parallel to a horizontal X-direction and a horizontal Y-direction perpendicular to the X-direction by a first positioning device, and the mask holder is displaceable parallel to the X-direction by a second positioning device. The substrate holder and the mask holder are displaced synchronously parallel to the X-direction during exposure of a semiconductor substrate. The second positioning device is capable of positioning the mask holder also parallel to the Y-direction and of rotating it about a vertical axis of rotation. Therefore, a displacement of the mask holder has a parallelism to the X-direction which is determined by a positioning accuracy of the second positioning device and which is not adversely affected by a deviation from parallelism and straightness of a guide of the second positioning device. An accuracy with which the semiconductor substrate is exposed is improved by a factor corresponding to an optical reduction factor of the focusing system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.