Methods of manufacturing a mask blank substrate, a mask blank, a photomask, and a semiconductor device

摘要

A before-chucking main surface shape is measured in an actual measurement region of a main surface of a substrate which has been precision-polished. Based on that shape and a shape of a mask stage (1), a simulated after-chucking main surface shape of the substrate, when a photomask (2) manufactured from the substrate is set in an exposure apparatus, is obtained. A selection is made of the substrate in which the after-chucking main surface shape has a flatness of a first threshold value or less in a virtual calculation region thereof. A calculation is performed and a selection is made of the substrate in which an after-correction main surface shape has a flatness of a second threshold value or less in the correction region.