NAKATANI Ryoichi Osaka University, Graduate School of Engineering, Professor, 大学院工学研究科, 教授 (60314374)
ENDO Yasushi Osaka University, Graduate School of Engineering, Assistant Professor, 大学院工学研究科, 助手 (50335379)
SHIRATSUCHI Yu Osaka University, Graduate School of Engineering, Assistant Professor, 大学院工学研究科, 助手 (70379121)
|Budget Amount *help
¥102,960,000 (Direct Cost: ¥79,200,000、Indirect Cost: ¥23,760,000)
Fiscal Year 2006: ¥8,580,000 (Direct Cost: ¥6,600,000、Indirect Cost: ¥1,980,000)
Fiscal Year 2005: ¥8,580,000 (Direct Cost: ¥6,600,000、Indirect Cost: ¥1,980,000)
Fiscal Year 2004: ¥16,900,000 (Direct Cost: ¥13,000,000、Indirect Cost: ¥3,900,000)
Fiscal Year 2003: ¥24,180,000 (Direct Cost: ¥18,600,000、Indirect Cost: ¥5,580,000)
Fiscal Year 2002: ¥44,720,000 (Direct Cost: ¥34,400,000、Indirect Cost: ¥10,320,000)
We have investigated magnetic properties and magnetization processes of sub-micron magnetic memory cells in order to find a breakthrough that increases a density of MRAM (magnetic random access memory).
(1) We have investigated method for recording magnetic memory. The magnetization direction of the asymmetric ring dots (material: 5-20 nm thick Ni-20at%Fe, diameter: 500-1000 nm) that have partly planed outer sides were controlled between clockwise and counterclockwise by in-plane magnetic fields, even though the ordinary ring dots needed the clockwise and counterclockwise magnetic fields caused by the perpendicular current.
(2) We also have found that the cup-shaped magnetic memory cell required lower magnetic field to be recorded than the ring memory.
(3) The Ni-Fe(10 nm)/Mn-Ir(10 nm) ring dot has fixed magnetization direction.
(4) The information recorded in the magnetic memory can be detected using atomic force microscopy with conductive probe.