| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To manufacture a product having no defect, by reliably detecting a minute internal defect in the whole region including a region close to the surface in the glass substrate. <P>SOLUTION: The method for manufacturing a glass substrate includes the following process. Inspecting light having a wavelength of 200 nm or less is introduced into a glass substrate for a mask blank, through one of the end surfaces of the glass substrate which is formed in a thin board shape having six surfaces, i.e., the front and rear surfaces 11, 12 as the main surfaces and four end surfaces 13, 14, 15, 16. Fluorescent light generated from an internal defect of the glass substrate by the inspecting light is detected so as to detect the internal defect of the glass substrate based on the detected fluorescent light. Upon detecting internal defects, the inspecting light entering the end surface is tilted at an angle of 2.0°to 4.0°with respect to the front and rear surfaces of the glass substrate. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
