Reflection type photomask and reflection type photolithography method comprising a concavo-convex surface
US5338647A · kind A · utility
10Cited by
1References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 22, 1992 |
| Grant date | Aug 16, 1994 |
| Priority date | — |
| Expiry date | Oct 22, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/26
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A reflection type photomask includes a substrate, and a reflecting surface formed on the substrate and including a first region and a second region which have a relative height difference. Due to the concavo-convex structure of the reflecting surface, a light reflected from the first region and a light reflected from the second region have a predetermined phase difference which may be used effectively to form a pattern on a photoresist layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.