| 摘要 |
PROBLEM TO BE SOLVED: To produce a highlyaccurate optical disk having finer and more precise lands and grooves by producing a metallic stamper of pure Ni or Ni-base alloy, pure Co or Co-base alloy or Fe-base alloy of polycrystalline metals having the unidirectionally solidified structure grown in a thickness direction. SOLUTION: An ingot 6 of the polycrystalline pure Ni or Ni-base alloy having the unidirectionally solidified structure grown in the thickness direction is sliced by slicing lines 7, by which polycrystalline metallic plates 8 of, for example, 150 mm in outside diameter and 1 mm in thickness are manufactured. The front and near surfaces of there polycrystalline metallic plate 8 are lapped and the front surface is mirror finished. The surfaces of produced substrates for stamper production are coated with photoresist layers. The photoresist layers are thereafter subjected to treatments, such as irradiation with Ar laser beams and Ar ions and ion milling, to form recessed parts and thereafter, the residual photoresist layers are removed, by which the polycrystalline metallic stamper is produced. As a result, the optical disk having the recessed parts of high accuracy may be produced.
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