Magnetic Tunnel Junction (MTJ) devices particularly suited for efficient spin-torque-transfer (STT) magnetic random access memory (MRAM) (STT MRAM) are disclosed. In one aspect, a MTJ structure with a reduced thickness first pinned layer provided below a tunnel magneto-resistance (TMR) barrier layer is provided. The first pinned layer provided below the TMR bather layer includes one pinned layer magnetized in only one magnetic orientation. In another aspect, a second pinned layer and a spacer layer are provided above a free layer and the TMR barrier layer in the MTJ. The second pinned layer is magnetized in a magnetic orientation that is anti-parallel to that of the first pinned layer. In yet another aspect, a giant magneto-resistance (GMR) spacer layer is provided as the spacer layer between the second pinned layer and the free layer in the MTJ.

A nonvolatile magnetic memory device having a magnetoresistance-effect element includes: (A) a laminated structure having a recording layer in which an axis of easy magnetization is oriented in a perpendicular direction; (B) a first wiring line electrically connected to a lower part of the laminated structure; and (C) a second wiring line electrically connected to an upper part of the laminated structure, wherein a high Young's modulus region having a Young's modulus of a higher value than that of a Young's modulus of a material forming the recording layer is provided close to a side surface of the laminated structure.