Photomask, method for manufacturing the same, and method for measuring optical characteristics of wafer exposure system using the photomask during operation
US7341809B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 12, 2006 |
| Grant date | Mar 11, 2008 |
| Priority date | — |
| Expiry date | May 12, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/706
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Provided are a photomask, a method for manufacturing the photomask and a method for measuring optical characteristics of a wafer exposure system, the measuring method using the photomask during manufacture. The photomask includes a substrate and a measuring pattern including a light opaque region pattern formed on the substrate and a plurality of light transmitting region patterns that are formed in regions divided by the light opaque region pattern and provoke phase shifts to provide phase differences to light transmitted through light transmitting regions. Precise measurements of the degree of a focus and lens aberrations of an exposure system using the photomask are obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.