Method and apparatus for repair of reflective photomasks
US7170030B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 2003 |
| Grant date | Jan 30, 2007 |
| Priority date | — |
| Expiry date | Aug 4, 2024 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K2103/50
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method of selectively ablating an undesired material from a substrate includes providing a substrate with two regions; providing laser pulses; tuning a wavelength of the laser pulses to match a desired wavelength characteristic of a material and directing the tuned laser pulses onto the substrate; and controlling a pulse duration, wavelength, or both, of the laser pulses to ablate the undesired material without damaging the substrate or any adjacent material. In another embodiment, an apparatus for repairing a defect on a reflective photomask includes a femtosecond pulse width laser; a harmonic conversion cell; a filter for passing a selected EUV harmonic of the laser light; a lens arrangement configured to direct the selected EUV harmonic of the laser light onto the photomask; and a control unit connected to the laser to control an ablation of the defect on the reflective photomask.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.