Method for manufacturing information recording medium

A method for manufacturing an information recording medium which prepares a plurality of information recording media in which a same digital data has been recorded, the method comprising:

• a master medium preparation step in which a process for recording digital data to be stored as a recess and protrusion structure pattern on a recording surface of a first recording medium is performed to prepare a master medium;
• an intermediate medium preparation step in which a process for transferring the recess and protrusion structure pattern recorded at the master medium onto a recording surface of a second recording medium is performed to prepare an intermediate medium;
• and
• a reproduction medium preparation step in which a process for transferring the recess and protrusion structure pattern recorded at the intermediate medium on a recording surface of a third recording medium is performed to prepare a reproduction medium;
• wherein
• in the master medium preparation step, a medium which includes a quartz glass substrate as the first recording medium is used to form a resist layer on a surface of the first recording medium, beam exposure is performed on a surface of the resist layer to draw a graphic pattern which shows bit information of digital data to be stored, the resist layer is developed to remove a part thereof, etching processing is performed, with a remaining part of the resist layer given as a mask, thereby preparing the master medium which includes a quartz glass substrate having a first recess and protrusion structure pattern on a surface thereof,
• in the intermediate medium preparation step, a shape formation process which utilizes the first recess and protrusion structure pattern formed on the surface of the master medium is performed to form, on the recording surface of the second recording medium, a second recess and protrusion structure pattern which is reverse in recess and protrusion relationship to the first recess and protrusion structure pattern,
• in the reproduction medium preparation step, a medium which includes a quartz glass substrate as the third recording medium is used to form, on the recording surface of the third recording medium, a third recess and protrusion structure pattern which is reverse in recess and protrusion relationship to the second recess and protrusion structure pattern by a shape formation process which utilizes the second recess and protrusion structure pattern formed on the surface of the intermediate medium wherein the recording surface of the third recording medium is etched,
• wherein the first recording medium and the third recording medium are first attribute mediums and the second recording medium is a second attribute medium, and in the shape formation process of the intermediate medium preparation step and the shape formation process of the reproduction medium preparation step, the second attribute medium is curved and peeled from the first attribute medium,
• wherein
• the master medium preparation step includes,
• a data input step in which a computer inputs digital data to be stored,
• a unit data creating step in which the computer divides the digital data by a prescribed bit length unit to create a plurality of unit data,
• a unit bit matrix creating step in which the computer arranges data bits which constitute individual unit data in a two-dimensional matrix form to create a unit bit matrix,
• a unit bit graphic pattern creating step in which the computer converts the unit bit matrix to a geometrical pattern arranged inside a predetermined bit recording domain, thereby creating a unit bit graphic pattern,
• a unit recording graphic pattern creating step in which the computer adds an alignment mark to the unit bit graphic pattern, thereby creating a unit recording graphic pattern,
• a drawing data creating step in which the computer creates drawing data for drawing the unit recording graphic pattern,
• a beam exposure step in which beam exposure which uses electron beams or laser light is performed on a substrate in which the resist layer is added on the first recording medium, thereby conducting drawing on the basis of the drawing data, and
• a patterning step in which patterning processing is performed on the substrate which has been exposed, thereby creating the master medium having a physically structured pattern depending on the drawing data, and
• wherein,
• in the unit bit graphic pattern creating step, one of individual bits “1” and individual bits “0” which constitute the unit bit matrix is converted to individual bit figures composed of a closed domain,
• in the drawing data creating step, there is created drawing data which shows a contour line of the individual bit figures,
• in the beam exposure step, beam exposure is performed on a part inside the contour line of the individual bit figures, and
• in the patterning step, there is formed a physically structured pattern which has a recess and protrusion structure composed of a recess which shows one of a bit “1” and a bit “0” and a protrusion which shows the other of them.