Method of annealing reflective photomask by using laser
US11934092B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 24, 2022 |
| Grant date | Mar 19, 2024 |
| Priority date | — |
| Expiry date | Oct 24, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/268
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A laser annealing method performed on a reflective photomask may include preparing a reflective photomask including a pattern area and a border area surrounding the pattern area and irradiating a laser beam onto the border area of the reflective photomask. The irradiating of the laser beam may include split-irradiating a plurality of laser beam spots onto the border area. Each of the plurality of laser beam spots may be shaped using a beam shaper. The beam shaper may include a blind area, a transparent area at a center of the blind area, and a semitransparent area between the blind area and the transparent area. Each of the plurality of laser beam spots may include a center portion passing through the transparent area and having a uniform energy profile and an edge portion passing through the semitransparent area and having an inclined energy profile.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.