Patent ID: 8333899

Claim:
A method of manufacturing a magnetic recording medium, comprising: forming, on a magnetic recording layer, a first hard mask made of a material selected from the group consisting of Mg, Al, Sc, Ti, V, Mn, Y, Zr, Nb, La, Ce, Nd, Sm, Eu, Gd, Hf, Zn, Sn, Pb, Ga, In and alloys thereof, a second hard mask made of a material selected from the group consisting of Cu, Ge, Ag, Ir, Pt, Au, Bi and alloys thereof, a third hard mask comprising carbon as a main component, and a resist; imprinting the resist with a stamper that transfers a pattern of protrusions and recesses to the resist; removing a residue in the recesses of the patterned resist; etching the third hard mask by use of the patterned resist as a mask, using O 2 or O 3 gas, that transfers the pattern of protrusions and recesses to the third hard mask; etching the second hard mask by use of the third hard mask as a mask, using a gas selected from the group consisting of SF 6 , CF 4 , Cl 2 and HBr, a gas obtained by mixing SF 6 , CF 4 , Cl 2 or HBr with He, Ne, Ar, Xe or Kr, an inert gas selected from the group consisting of He, Ne, Ar, Xe or Kr, or a gas obtained by mixing He, Ne, Ar, Xe or Kr with N 2 , that transfers the pattern of protrusions and recesses to the second hard mask; etching the first hard mask by use of the second hard mask as a mask, using a gas selected from the group consisting of SF 6 , CF 4 , Cl 2 and HBr, a gas obtained by mixing SF 6 , CF 4 , Cl 2 or HBr with He, Ne, Ar, Xe or Kr, an inert gas selected from the group consisting of He, Ne, Ar, Xe or Kr, or a gas obtained by mixing He, Ne, Ar, Xe or Kr with N 2 , that transfers the pattern of protrusions and recesses to the first hard mask; patterning the magnetic recording layer with ion beam irradiation; and removing the first hard mask with a remover liquid having higher reactivity to the metal material of the first hard mask than to a constituent element of the magnetic recording layer.