Patent Number: 6,165,649

Title: Methods for repair of photomasks

Abstract: A method of repairing defects on masks includes the step of providing a coating on the mask to prevent damage to clear regions of the mask from laser ablation splatter, laser ablation caused quartz pitting, laser deposition staining, and FIB caused gallium staining. The coating is a metal, a polymer, or a carbon material. The coating is formed on clear regions of the mask as well as either over or under the light absorbing material of the mask. A coating comprising a thin copper layer significantly improves imaging with the ion beam while protecting clear regions of the mask from FIB stain. A coating formed of a photosensitive polymer is used to etch opaque defects. While wanted opaque regions adjacent an opaque defect are also etched in this etch step, these created clear defects are then repaired in a subsequent FIB deposition step while a copper coating protects adjacent clear regions from FIB stain. In another embodiment, opaque defects are repaired with a short pulse duration laser without damage to underlying quartz or adjacent clear regions while avoiding the need for a coating.

Inventors: Grenon; Brian J. (Colchester, VT), Haight; Richard A. (Mahopac, NY), Hayden; Dennis M. (Essex Junction, VT), Hibbs; Michael S. (Westford, VT), Levin; J. Peter (Winooski, VT), Neary; Timothy E. (Essex Junction, VT), Rochefort; Raymond E. (South Burlington, VT), Schmidt; Dennis A. (South Burlington, VT), Smolinski; Jacek G. (Jericho, VT), Wagner; Alfred (Brewster, NY)

Assignee: International Business Machines Corporation

International Classification: G03F 1/00 (20060101); G03F 009/00 ()

Expiration Date: 12/26/2017