Integrated circuit photomask
US4411972A · kind A · utility
24Cited by
15References
25Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 30, 1981 |
| Grant date | Oct 25, 1983 |
| Priority date | — |
| Expiry date | Dec 30, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24992
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A photomask formed of a transparent dielectric substrate, such as glass and quartz based substrates, having a conductive surface adjacent region, which is patterned with sequential overcoatings of a composite chrome oxide layer and a chrome film. The mask comprises a combination of varied reflectivities to provide proper densities for the opaque areas of the mask.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.