Phase shift mask for formation of contact holes having micro dimension
US5897975A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 28, 1995 |
| Grant date | Apr 27, 1999 |
| Priority date | — |
| Expiry date | Nov 28, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/34
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A phase shift mask capable of forming contact holes having a micro dimension smaller than the wavelength of exposure light while being spaced at small intervals. The phase shift mask includes a quartz substrate, a chromium pattern formed on the quartz substrate along a peripheral edge of the quartz substrate, and a plurality of uniformly spaced phase shift layer patterns formed on a portion of the quartz substrate not covered with the chromium pattern, each of the phase shift layer patterns having a desired size. Each of the phase shift layer patterns has a line width larger than the wavelength of a light source used in a light exposure procedure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.