Recently, mask inspection for extreme ultraviolet lithography has been in the spotlight as the next-generation lithography technique in the field of semiconductor production. This technology is used to make semiconductors more delicate even as they become tinier. In mask inspection, defect sizes and locations are major factors for aggravating mask defects which cause errors on wafer patterns. This paper addresses a simulated solution of coherent scattering stereoscopic microscopy for considering the mitigation of mask defects. To perform the inspection of mask defects for the stereoscopic microscopy, we construct a stereo aerial image with a disparity map produced by a Hybrid input-output algorithm and disparity estimation methods. Preliminary results show that mask inspection by coherent scattering stereoscopic microscopy is expected to be performed in a more accurate way compared to 2D mask inspection.