To eliminate the damage to the filmy base material at the time of subjecting the filmy base material to plasma treatment by enhancing the film formation rate at the time of forming a diamond-like carbon film on a filmy base material with a CVD (chemical vapor deposition) method in the manufacture of this recording medium.
In the manufacturing device of this recording medium, a plasma treatment device is provided with a vacuum vessel 6 having a plasma treatment vessel, a means for supplying a gaseous reactant 2 to the plasma treatment vessel and a mechanism for introducing a filmy base material 16 into the plasma treatment vessel and transferring the filmy base material 16 from the plasma treatment vessel. At this time, a high-frequency voltage 1 is applied to a counter electrode 3 placed opposite to the filmy base material 16 that is introduced onto an earth electrode 8, to retain a plasma in the plasma treatment vessel. By using the counter electrode 3 having a sufficiently larger area than that of the earth electrode 8 within the plasma treatment vessel, high energy ions are allowed to flow out to the surface to be treated of the filmy base material 16, and also, the capacitance of the device structure can be minimized by incorporating the counter electrode 3 into the vacuum vessel 6 as a part of the vessel 6, and further, a part of the surface of a magnetic layer formed on the other surface of the filmy base material 16 is electrically earthed with a ≥100mm2 contact area.
KATAOKA HIROYUKI
FUJIMAKI SHIGEHIKO
YANO AKIRA
MIZUMURA TETSUO
KUSADA HIDEO
ASANO MICHIO
HITACHI MAXELL