| 摘要 |
PROBLEM TO BE SOLVED: To appropriately select a mask blank substrate which is less susceptible to birefringence.SOLUTION: A method of manufacturing a mask blank substrate using a translucent substrate having a pair of opposing main surfaces and at least two pairs of end surfaces includes: a measurement step S202 for introducing circularly polarized inspection light into a translucent substrate from one of the main surfaces or end surfaces, splitting the inspection light exiting from a main surface or an end surface opposite the incident main surface or end surface into two linearly polarized light beams whose wavefronts are orthogonal to each other, and measuring the intensity of each linearly polarized light beam; a computation step S204 for computing a light intensity ratio which is obtained by dividing one of the measured light intensity values of the two linearly polarized light beams acquired in the measurement step S202 by the sum of the measured light intensity values of the two linearly polarized light beams; and a selection step S206 for selecting a translucent substrate suitable to be used as a mask blank substrate based on the computed light volume ratio. |
