| 摘要 |
PURPOSE:To obtain an optical recording medium having excellent durability and high reliability by using a ceramic film consisting of silicon oxide and at least one kind of oxides among beryllium oxide, magnesium oxide, calcium oxide, strontium oxide, and barium oxide as protective films of the optical recording medium. CONSTITUTION:The protective films 12, 14 and a recording film 13 consisting of a GdTbFe film which is a rare earth-transition metallic compd. are provided on a polycarbonate substrate 11. The material having the compsn. expressed by the formula A.SiOx (where A denotes the oxide consisting of at least one kind among the beryllium oxide, magnesium oxide, calcium oxide, strontium oxide, and barium oxide and X is 0<x<2) is used as the protective films 12, 14. The protective films which have a high film forming speed and small residual stresses of the film and are resistant to cracking are thereby obtd. even if a plastic substrate is used. The power to prevent the oxidation and corrosion of the recording film is large and the deterioration of recording and reproducing characteristics with age is suppressed. |
