Re-based alloys usable as deposition targets for forming interlayers in granular perpendicular magnetic recording media & media utilizing said alloys

A granular perpendicular magnetic recording medium, comprising:

• (a) a non-magnetic substrate having a surface;
• and
• (b) a layer stack on said substrate surface, said layer stack including, in order from said surface:
• (i) a non-magnetic or substantially non-magnetic interlayer;
• and
• (ii) a granular perpendicular magnetic recording layer in overlying contact with said interlayer, wherein:
• said interlayer comprises a Re-based alloy material, comprising >50 at. % Re and at least one alloying material selected from the group consisting of:
• grain size refinement elements X which have an atomic radius larger or smaller than that of Re and a solid solubility <˜6 at. % in hcp Re at room or higher temperatures, and lattice matching elements Y which have an atomic radius different from that of Re and form a solid solution in hcp Re at room or higher temperatures.

A method of fabricating a granular perpendicular magnetic recording medium, comprising steps of:

• (a) providing a non-magnetic substrate having a surface;
• and
• (b) forming a layer stack on said substrate surface, said layer stack including, in order from said surface:
• (i) a non-magnetic or substantially non-magnetic interlayer;
• and
• (ii) a granular perpendicular magnetic recording layer in overlying contact with said interlayer, wherein:
• said interlayer comprises a Re-based alloy material, comprising >50 at. % Re and at least one alloying material selected from the group consisting of:
• grain size refinement elements X which have an atomic radius larger or smaller than that of Re and a solid solubility <˜6 at. % in hcp Re at room or higher temperatures, and lattice matching elements Y which have an atomic radius different from that of Re and form a solid solution in hcp Re at room or higher temperatures.

The method according to claim 25, wherein step (b) comprises performing one of the following alternative sputter deposition processes:

• (a) sputter deposition utilizing a target comprised of a Re—X alloy, where Re >50 at. % and X is at least one element selected from the group consisting of:
• Be, B, Si, Ti, V, Mn, Fe, Cu, Ge, Se, Y, Zr, Nb, Pd, Ag, Sn, Sb, Te, La, Nd, Sm, Gd, Tb, Ho, Er, Yb, Lu, Hf, Ta, Bi, Th, and U;
• (b) sputter deposition utilizing a target as in alternative (a), said target further comprising at least one material selected from the group consisting of oxides, nitrides, and carbides;
• (c) sputter deposition utilizing a target comprised of a Re—Y alloy, where Re >50 at. % and Y is at least one element selected from the group consisting of:
• Al, Mo, W, Os, Pt, Au, C, Cr, Co, Ni, Ir, Ru, Rh, and Os;
• (d) sputter deposition utilizing a target as in alternative (c), said target further comprising at least one material selected from the group consisting of oxides, nitrides, and carbides;
• (e) sputter deposition utilizing a target comprised of a Re—X—Y alloy, where Re >50 at. %, X is at least one element selected from the group consisting of:
• Be, B, Si, Ti, V, Mn, Fe, Cu, Ge, Se, Y, Zr, Nb, Pd, Ag, Sn, Sb, Te, La, Nd, Sm, Gd, Tb, Ho, Er, Yb, Lu, Hf, Ta, Bi, Th, and U, and Y is at least one element selected from the group consisting of:
• Al, Mo, W, Os, Pt, Au, C, Cr, Co, Ni, Ir, Ru, Rh, and Os;
• (f) sputter deposition utilizing a target as in alternative (e), said target further comprising at least one material selected from the group consisting of oxides, nitrides, and carbides;
• (g) sputter deposition utilizing a first target as in alternative (a) and a second target as in alternative (c);
• and
• (h) sputter deposition utilizing a first target as in alternative (a) and a second target as in alternative (c), at least one of said first and second targets further comprising at least one material selected from the group consisting of oxides, nitrides, and carbides.