| 摘要 |
PROBLEM TO BE SOLVED: To obtain a thin film having high weatherability and free from the generation of deterioration in reproduced signals by using the one obtd. by incorporating a specified amt. of Pd into Ag as a sputtering target material. SOLUTION: Preferably, this material is an Ag alloy in which Ag is incorporated with 0.5 to 4.9 atomic % Pd, and one or two kinds of elements of Cu and Cr are moreover added thereto respectively by 0.1 to 3.5 atomic % or an Ag alloy in which Ag is incorporated with 0.5 to 1.5 atomic % Pd, and 0.1 to 2.9 atomic % Ti is moreover incorporated therein. For example, as to an optical recording medium 10, a 1st substrate 1 has 1st fine ruggedness 21 such as data recording pits or the like and a translucent film 15 to form a 1st information recording layer 13. A 2nd substrate similarly has 2nd fine ruggedness 22 and a reflecting film formed of a silver alloy to form a 2nd information recording layer 12. By applying light beams with different wavelength in such a manner that the focuses are connected onto the 1st and 2nd information recording layers 11 and 12, information is reproduced. By the interaction between Ag and Pd, high weatherability can be obtd. |
