Patent ID: 8113014

Claim:
A method of manufacturing a glass substrate for a recording medium comprising: conducting a first lapping process of polishing a first surface of a glass substrate and polishing a second surface of the glass substrate to adjust parallelism, flatness and thickness of the first surface and the second surface; subsequent to completion of the first lapping process, conducting a second lapping process of polishing the first surface and polishing the second surface to finely adjust parallelism, flatness and thickness of the first surface and the second surface; subsequent to completion of the second lapping process, conducting a chemical strengthening process by which the glass substrate, held by a holding jig, and the holding jig are immersed in a chemical strengthening solution, and a first alkali metal ion on the first surface of the glass substrate is substituted by a second alkali metal ion contained in the chemical strengthening solution and having a larger ion diameter than that of the first alkali metal ion, wherein the holding jig comprises a member of material, made of a metal comprising an alkali metal element; and subsequent to completion of the chemical strengthening process, conducting a polishing process by precisely polishing the first surface and precisely polishing the second surface to complete the glass substrate for use with a recording medium.