Method of and apparatus for aligning a substrate
US4833621A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 3, 1987 |
| Grant date | May 23, 1989 |
| Priority date | — |
| Expiry date | Jun 3, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/70
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
in the production of semiconductor devices, for example, high-accuracy, high-speed alignment of different exposure areas of a wafer with respect to a reticle is achieved by the use, for each exposure area, of a predetermined number of sampling areas that are selected so as to be adjacent to a selected exposure area. A position detector produces position information signals regarding the positions of a plurality of sampling areas and stores the position information signals in a memory. Design data indicating positions of a plurality of sampling areas are also stored in memory. A calculator calculates a correction value for the selected exposure area on the basis of the position information signals and the design data for the selected sampling areas. The wafer is then displaced relative to the reticle in accordance with the correction value and design data for the selected exposure area.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.