US Patent 7596058 Recording medium having multiple magnetic layers

The magnetic recording medium comprises a backing layer including a first magnetic layer, a second magnetic layer which is formed over the first magnetic layer, is ferrimagnetic and is magnetized in a direction opposite to the first magnetic layer, and a third magnetic layer formed over the second magnetic layer and magnetized in a direction opposite to the second magnetic layer; and a perpendicular magnetic recording layer for recording magnetic information formed over the backing layer. Antiferromagnetic exchange interconnection is formed between the first magnetic layer and the second magnetic layer and between the second magnetic layer and the third magnetic layer.