公开(公告)号：US20200075053A1

公开(公告)日：2020-03-05

申请号：US16519157

申请日：2019-07-23

申请人： SHOWA DENKO K.K.

发明人： Takayuki FUKUSHIMA ,  Koji TAKE ,  Hisato SHIBATA ,  Takehiro YAMAGUCHI ,  Tomoo SHIGE ,  Lei ZHANG ,  Chen XU ,  Yuji UMEMOTO ,  Hiroshi KOYANAGI ,  Kazuya NIWA ,  Tetsuya KANBE

IPC分类号： G11B11/105 ,  G11B5/73 ,  G11B11/24

摘要： A heat-assisted magnetic recording medium includes a substrate, an underlayer, and a magnetic layer including an alloy having a L10 crystal structure and first and second layers, arranged in this order. Each of the first and second layers has a granular structure including C, SiO2, and BN at grain boundaries. Vol % of the grain boundaries in each of the first and second layers is 25 to 45 vol %. Vol % of C in the first layer is 5 to 22 vol %, and a volume ratio of SiO2 with respect to BN in each of the first and second layers is 0.25 to 3.5. Vol % of SiO2 in the second layer is greater than that of the first layer by 5 vol % or more. Vol % of BN in the second layer is smaller than that in the first layer by 2 vol % or more.