Abstract: In one embodiment, a perpendicular magnetic recording medium includes an oxide recording layer including an oxide and a non-oxide recording layer which does not contain an oxide positioned above the oxide recording layer. The oxide recording layer includes a region R1 where a grain boundary width in a direction parallel to a plane of formation of R1 increases therealong from a lowermost portion of the oxide recording layer toward a medium surface, a region R3 positioned above R1 wherein a grain boundary width increases therealong toward the medium surface, a region R2 where a grain boundary width of R2 decreases therealong from R1 to R3, with R2 being positioned between R1 and R3, and a region R4 where a grain boundary width of R4 decreases therealong from R3 toward the medium surface, with R4 being positioned above R3 and near an uppermost portion of the oxide recording layer.

Abstract: Disclosed is a method of testing a magnetic recording medium including a magnetically isolated magnetic recording pattern (41a) on a non-magnetic substrate. The method includes: a first signal writing step of writing a first signal (6) with a width less than a track width at a plurality of measurement positions (5) on the magnetic recording pattern (41a) using a writing head; a first signal reading step of reading the first signal (6) using the reading head to obtain a plurality of first read signals corresponding to the measurement positions (5); and an analysis step of analyzing magnetic characteristics of the magnetic recording pattern (41a) using the plurality of first read signals obtained in the first signal reading step. The test method is suitable for testing the magnetic characteristic distribution of a discrete track medium and is capable of testing the magnetic characteristic distribution of a magnetic recording medium with high accuracy.

Abstract: A production method for a magnetic recording medium including forming thin films on a substrate using a sputtering method with a target, wherein the target on which an annular-shaped erosion area is formed during sputtering and a substrate holder on which a plurality of substrates are mounted are installed, opposed in parallel, in a manner such that center axes of the target and the substrate holder align with each other, and the substrates are mounted on the substrate holder in positions such that R3/R1 is 1.1 or smaller and R4 is R2 or greater to form thin films.