Method of repairing a defect in a lithographic mask comprising metal deposition from solution via U.V. stimulated electron emission

Abstract

The invention provides a method by which a transparent defect (3) in a lithographic mask (1) can be effectively restored in a simple manner. For this purpose, the mask (1) is provided with a photosensitive layer (4) and is introduced into a solution of a metal ion (5). Subsequently, the mask is exposed at the area of the defect. The photosensitive layer (4) is capable of depositing the metal ion in the form of metal under the influence of the radiation (6) supplied. According to the invention, the exposure is continued until such a quantity of metal (7) has been deposited that the radiation can no longer penetrate to the photosensitive layer (4). At that instant, the metal deposition is stopped so that overgrowth of the metal deposit (7) is automatically counteracted in a simple manner.

Dependencies are inferred from the claim text.