Patent ID: 7532436
Filing Date: 2009-05-12
Classification: G11B

Abstract:
1. A magnetic recording medium in which at least a first magnetic layer, a spacer layer comprising Ru as a main ingredient, a second magnetic layer, and a third magnetic layer are formed in contact with each other in order on a substrate, wherein a thickness of the second magnetic layer is larger than a thickness of the third magnetic layer and the total for the concentrations of cobalt and platinum contained in the second magnetic layer is not higher than the total for the concentrations of cobalt and platinum contained in the third magnetic layer; wherein platinum is contained in the first magnetic layer, the second magnetic layer, and the third magnetic layer; and wherein the concentration of platinum contained in the second magnetic layer is higher than the concentration of platinum contained in the first magnetic layer, and the concentration of platinum contained in the third magnetic layer is higher than the concentration of platinum contained in the second magnetic layer.