To make it possible to easily produce a stamper by incorporating a step of forming an easily removable auxiliary thin film having grooves for tracking into a production process.
The auxiliary thin-film layer 2 consisting of a material which is different from the material of a phase transition film 4 formed on a substrate 1 and is easily removable is formed by etching on the substrate 1 prior to the formation of the phase transition film 4 in the case of producing the stamper for optical disks by subjecting the phase transition film 4 to thermal recording of information by a laser beam L1 and etching this film and forming the signal ruggedness on the surface of the substrate 1 by utilizing difference in the etching rate between the phase transition parts and the phase non-transition parts. Grooves 3 for tracking are formed on this auxiliary thin-film layer 2 and, thereafter, the phase transition film 4 is formed on the auxiliary thin-film layer 2. As a result, the stamper is formed without using a high-accuracy recording machine used before.
MIYAJIMA SHIN
ASANUMA TOYOHITO
SUZUKI TETSUYA
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