Abstract: A method for repairing mask-blank defects uses repair-zone compensation. Local disturbances are compensated over the post-defect-repair repair-zone by altering a portion of the absorber pattern on the surface of the mask blank. This enables the fabrication of defect-free (since repaired) X-ray Mo—Si multilayer mirrors. Repairing Mo—Si multilayer-film defects on mask blanks is a key for the commercial success of EUVL. It is known that particles are added to the Mo—Si multilayer film during the fabrication process. There is a large effort to reduce this contamination, but results are not sufficient, and defects continue to be a major mask yield limiter.

Abstract: Ion-beam based deposition technique are provided for the planarization of pit and scratch defects in conjunction with particle defects. One application of this planarization technique is to mitigate the effects of pits and scratches and particles on reticles for extreme ultraviolet (EUV) lithography. In the planarization process, thin Si layers are successively deposited and etched away where the etching is directed at angles well away from normal incidence to the substrate to planarize pits and scratches without causing the particle defects to get too large; this is followed by a normal incidence etching process sequence designed primarily to planarize the particles but which will also planarize the pits and scratches to completion. The process also shows significant promise for planarizing substrate roughness.