MANUFACTURING METHOD OF GLASS SUBSTRATE FOR MASK BLANKS AND MANUFACTURING METHOD OF MASK BLANKS

摘要

PROBLEM TO BE SOLVED: To provide a highly accurate and efficient manufacturing method of a glass substrate for mask blanks.;SOLUTION: The manufacturing method of the glass substrate 100 for the mask blanks comprises a glass polishing process polishing a main surface of the glass substrate. The glass polishing process has a polishing stage polishing the main surface, a substrate thickness detection stage which irradiates the front surface side or the back surface of the glass substrate with light, and detects the thickness of the glass substrate 100 based on the reflected light from the main surface of the front surface side and the main surface of the back surface side respectively, and an end determination stage which ends the glass polishing process when the detected thickness is compared with a predetermined value, and the thickness becomes the predetermined thickness or smaller than that value. The manufacturing method comprises a polishing device 10, a polishing part 12, a light irradiation part 14, a substrate thickness detection part 16, an end determination part 18, a washing water supply part 20, a lower surface plate 24, a polishing liquid supply part 26, a polishing pad 32, and a polishing pad 34.;COPYRIGHT: (C)2006,JPO&NCIPI