Abstract: A magnetic recording medium comprising a non-ferromagnetic substrate and a magnetic recording layer formed on the substrate with an underlayer of Cr or a Cr alloy interposed therebetween, which has a seed layer between the substrate and the underlayer, wherein said seed layer is made of a material which contains at least 30 ppm of oxygen and which has a B2 crystal structure.

Abstract: A magnetic recording medium comprising a non-ferromagnetic substrate and a magnetic recording film formed on the substrate with an underlayer interposed therebetween, wherein the magnetic recording film comprises a plurality of magnetic layers and an interlayer made of a material having a B2 crystal structure or an interlayer made of Ru, disposed between the adjacent magnetic layers.

Abstract: A substrate for a magnetic recording medium. The substrate is a non-magnetic brittle material having a substantially flat surface on which laser marks having a height in a range of 10-500 .ANG. are formed in a landing zone. The laser marks are formed by irradiating a pulsed laser beam having a wavelength capable of being absorbed in the non-magnetic brittle material within a range of substantially circular form having a waist diameter D .mu.m, and which has a physical property of 0.5<E.sup.v /(D/20).sup.2 <6 .mu.J where E.sup.v .mu.J represents a pulse energy for initiating vaporization of the glass substrate by irradiation of the pulsed laser.

Abstract: A magnetic recording medium having a magnetic thin film, wherein crystal grains constituting the magnetic thin film are separated by a crystal boundary region containing a non-ferromagnetic and non-metallic phase. The magnetic recording medium of the present invention provides a high coercivity and a remarkably reduced media noise property, and a high productivity in the mass production thereof.