title: Repairing amplitude defects in multilayer-coated extreme-ultraviolet lithography reticles by use of a focused ion beam.
abstract: We present a method for repairing defects near the top surfaces of multilayer coatings in general and specifically on extreme-ultraviolet lithography mask blanks. Milling away the defect and a surrounding region of the multilayer by use of a focused ion beam can repair both the reflectivity and the phase of the reflected light in the vicinity of such a defect. We describe the conditions under which the repaired region will not itself be a defect and experimentally demonstrate the feasibility of this multilayer repair technique. The results described are also applicable to understanding and controlling the optical effects of ion-induced multilayer erosion.
authors.affiliation: Lawrence Livermore National Laboratory, Livermore, California 94550, USA. barty2@llnl.gov
authors.forename: Anton
authors.initials: A
authors.lastname: Barty
authors.forename: Stefan
authors.initials: S
authors.lastname: Hau-Riege
authors.forename: Dan
authors.initials: D
authors.lastname: Stearns
authors.forename: Miles
authors.initials: M
authors.lastname: Clift
authors.forename: Paul
authors.initials: P
authors.lastname: Mirkarimi
authors.forename: Eric
authors.initials: E
authors.lastname: Gullikson
authors.forename: Henry
authors.initials: H
authors.lastname: Chapman
authors.forename: Don
authors.initials: D
authors.lastname: Sweeney