Optical recording medium and recording material for the same

An optical recording medium, comprising:

• a substrate;
• a first recording structure, comprising:
• a first dielectric layer disposed over the substrate;
• and
• a first recording layer disposed on and in contact with the first dielectric layer:
• a second recording structure arranged over the first recording structure, and comprising:
• a second dielectric layer disposed over the first recording layer;
• and
• a second recording layer disposed on and in contact with the second dielectric layer;
• a third recording structure arranged over the second recording structure, and comprising:
• a third dielectric layer disposed over the second recording layer;
• and
• a third recording layer disposed on and in contact with the third dielectric layer;
• and
• a first, a second, a third, a fourth, a fifth and a sixth passivation layer, wherein the first and second passivation layers are respectively disposed below and above the first recording structure, the third and fourth passivation layers are respectively disposed below and above the second recording structure, and the fifth and sixth passivation layers are respectively disposed below and above the third recording structure;
• wherein each of the first, second and third recording layers has an extinction coefficient of less than or equal to 0.3 and comprises a material represented by a composition formula of BixGeyO(1-x-y), wherein x and y respectively represent atomic ratios of bismuth and germanium, and satisfy the requirements of the following formulae:
• 2.8≦(x/y)≦25 and 0.55≦(1−x−y)<0.62;
• and
• wherein each of the first, second and third dielectric layers has a refractive index of about 2.0 to about 2.5.