METHOD FOR MODIFYING VOID DEFECTIVE PART OF HALFTONE PHASE SHIFTING MASK

摘要

PROBLEM TO BE SOLVED: To provide a method for modifying the void defective part of a halftone phase shifting mask capable of accurately modifying the void defective part of the light shielding pattern of the halftone phase shifting mask. SOLUTION: In the method for modifying the void defective part of a halftone phase shifting mask in which a void defective part generated in the phase shifter of a halftone phase shifting mask is modified with an FIB (focused ion beam) modifying machine, an engraved part is formed by ion etching with the FIB modifying machine in a part corresponding to the void defective part, the depth of the engraved part is set in accordance with exposure wavelength to produce a phase shifting effect and the void defective part generated in the phase shifter is modified by forming a light shielding thin film whose transmissivity is nearly equal to that of the phase shifter on the bottom of the engraved part.