Alignment apparatus
US4677301A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 1984 |
| Grant date | Jun 30, 1987 |
| Priority date | — |
| Expiry date | Dec 14, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/70
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A position alignment apparatus aligns a photosensitive substrate and a mask (projection image) at high speed and with high precision. The apparatus has a projection optical system for projecting a pattern image on a mask or reticle onto a photosensitive substrate, a detector for detecting a two-dimensional misalignment of a projected pattern image and a wafer, and means for moving the wafer along orthogonal x- and y-axis directions and for rotating the wafer along a rotational direction within a plane defined by the x- and y-axis directions so as to eliminate the misalignment, wherein the detector has first detecting means with an optical system for detecting at least a misalignment of the wafer along the x-axis direction through the projection lens, and second detecting means with an optical system separate from the projection lens and for detecting at least a misalignment of the wafer along a rotational direction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.