6533b82afe1ef96bd128ca83
RESEARCH PRODUCT
Actinic inspection of sub-50 nm EUV mask blank defects
J. MaulKarsten RottG. SchoenhenseM. MerkelJingquan LinUlf KleinebergStefan HendelN. Webersubject
Materials sciencebusiness.industryExtreme ultraviolet lithographyMask inspectionlaw.inventionStanding wavePhotoemission electron microscopyWavelengthOpticslawExtreme ultravioletOptoelectronicsPhotolithographyPhotomaskbusinessdescription
A new actinic mask inspection technology to probe nano-scaled defects buried underneath a Mo/Si multilayer reflection coating of an Extreme Ultraviolet Lithography mask blank has been implemented using EUV Photoemission Electron Microscopy (EUV-PEEM). EUV PEEM images of programmed defect structures of various lateral and vertical sizes recorded at around 13 nm wavelength show that 35 nm wide and 4 nm high buried line defects are clearly detectable. The imaging technique proves to be sensitive to small phase jumps enhancing the visibility of the edges of the phase defects which is explained in terms of a standing wave enhanced image contrast at resonant EUV illumination.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2007-02-08 | 23rd European Mask and Lithography Conference |