| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent the occurrence of surface defects and deterioration of surface roughness in a polishing step when a locally worked glass substrate surface is polished. <P>SOLUTION: In a method for manufacturing a glass substrate for mask blanks comprising an irregularity form measuring step of measuring the irregularity form of a glass substrate surface, a flatness controlling step in which the protrusion degree of protruding portions present on the glass substrate surface is determined on the basis of the results of measurement obtained in the irregularity form measuring step and the flatness of the glass substrate surface is controlled to a prescribed reference value or below by locally working the protruding portions under working conditions set according to the protrusion degree, and a polishing step of polishing the locally worked glass substrate surface after the flatness controlling step, the locally worked glass substrate surface is acid- or alkali-treated after the flatness controlling step and before the polishing step. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
