Method of mending a defect in a phase shift pattern
US5468337A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 6, 1993 |
| Grant date | Nov 21, 1995 |
| Priority date | — |
| Expiry date | Apr 6, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/26
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method to mend a black defect and a white defect of a phase shift mask pattern so that the mended phase shift mask pattern has an accurately defined pattern. In the vicinity of a black defect and the area around the same, a mending phase shifter is formed into a thickness twice as large as the thickness d of a phase shifter. All light beams through a black defect area are nearly 0 degree out of phase with a non-phase-shifted light beam, thereby the phase shift mask pattern having the black defect becoming a phase shift mask pattern with an accurately defined pattern. In a similar manner, every light beam through a white defect area is nearly 180 degree out of phase with a non-phase-shifted light beam. As a result, a mended phase shift mask pattern has an accurately defined pattern.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.