摘要 |
PURPOSE: An STT-MRAM device comprising a multi-level cell and a driving method thereof are provided to obtain various resistances according to the degree of magnetization at each magnetization reverse device. CONSTITUTION: A memory layer(230) is formed on a bottom electrode(220). A plurality of magnetization reverse devices(231) and a conductive layer are laminated alternately to form a memory layer. When a current higher than threshold current density is flowed, the plural magnetization reverse devices are reversed through spin transmitting torque. The top electrode is formed on the memory layer. At least two of plural magnetization reverse devices have different threshold current density. The plural magnetization reverse devices have different resistance.
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