VERFAHREN UND VORRICHTUNG ZUR GUETEPRUEFUNG VON MASKEN.

摘要

A method of inspecting masks which have lithographic patterns thereon, comprises the steps of depositing an electron-emissive layer on the patterned first major surface of the mask, the electron-emissive layer on the clear area of the patterned surface emitting electron beams when irradiated with energy beams, applying energy beams to the patterned surface from behind through the second major surface of the mask, guiding the electron beams emitted from the electron-emissive layer to an electron optical system, thereby forming an electron beam image of the pattern on a detector means, and comparing detection signals corresponding to the pattern and output by the detector means with reference signals representing the design shape and size of the pattern, thereby to inspect the mask.