摘要 |
The invention provides a method of manufacturing a glass substrate for magnetic recording media. And the glass substrate has high surface smoothness and little waviness. In the primary, secondary and tertiary lapping process, diamond pads 20A, 20B, and 20C are used, respectively. The diamond pad 20A has an average diamond grain size of 4 to 12μm, and a content of diamond grains of 5 to 70% by volume. The diamond pad 20B has an average diamond grain size of 1 to 5μm, and a content of diamond grains of 5 to 80% by volume. The diamond pad 20C has an average diamond grain size of 0.2 to 2μm, and a content of diamond grains of 5 to 80% by volume. In the polishing process, the silicon oxide is used as abrasive without using cerium oxide, and before the polishing process, an etching process is provided. |