Alignment method
US4811059A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 2, 1987 |
| Grant date | Mar 7, 1989 |
| Priority date | — |
| Expiry date | Oct 2, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F9/70
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An improved alignment method usable in a step-and-repeat type alignment and exposure apparatus for photolighographically transferring images of a pattern of a reticle onto different shot areas on a semiconductor wafer, for manufacture of semiconductor devices. According to this method, the alignment is executed with respect to an X direction, a Y direction and a rotational direction parallel to a plane containing the X and Y directions. With regard to the rotational direction, positional deviation of the wafer as a whole with respect to the reticle is measured and corrected prior to the initiation of the step-and-repeat photoprinting. With regard to the X and Y directions, detection and correction of any deviation are executed for each of the shot areas of the wafer. By this, high-accuracy and high-speed alignment is attainable for all the shot areas of the wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.