To provide a silicon substrate for a magnetic recording medium and its manufacturing method capable of improving dimensional accuracy of a circular hole at the center of a substrate and preventing occurrence of flaw due to friction with a spindle, and provide a magnetic recording medium using the silicon substrate and a magnetic recording device.
A lot of silicon substrates are finished so that the dimensional accuracy (maximum value - minimum value) of the inside diameter of the circular hole of the center is within 4 μm. As for the manufacturing method, a lot of pieces of silicon substrate laminated bodies are prepared, a brush polishing is performed after the circular hole of the center is ground, and the silicon substrate laminated bodies are reversed ups and downs in the middle of the brush polishing process. A magnetic layer is formed on a main surface of the silicon substrate obtained thereby, made to be the magnetic recording medium, and a magnetic recording device incorporating the magnetic recording medium.
Tadashi Takahashi
Takashi Watanabe
Masakazu Aoyama
Suzuki Mitsuyoshi
Kazuya Nishi
Yasuhiko Murayama