Half-metal ferromagnetic junction structure, five-layer magnetic tunnel junction device using the same, and magnetic memory device

摘要

PROBLEM TO BE SOLVED: To provide a half-metal ferromagnetic junction structure which enables the modulation of the spin polarization of a half-metal ferromagnetic layer, and a multiferroic structure.SOLUTION: A combination of a metal ferromagnetic layer 1 as a free layer, a tunnel barrier layer 2 and a half-metal ferromagnetic layer 3 as a pin layer constitutes a three-layer tunnel junction (MTJ) structure S1. To the three-layer MTJ structure S1, a ferroelectric layer 4 having an intrinsic polarization P is bonded on the side of the half-metal ferromagnetic layer 3 and further, a conductive layer 5 is bonded under the ferroelectric layer 4, thereby modulating the spin polarization of the half-metal ferromagnetic layer 3. A combination of the half-metal ferromagnetic layer 3, the ferroelectric layer 4 and the conductive layer 5 constitutes a half-metal ferromagnetic junction structure S2. A combination of the three-layer MTJ structure S1 and the half-metal ferromagnetic junction structure S2, which share the half-metal ferromagnetic layer 3, constitutes a five-layer MTJ element S3.SELECTED DRAWING: Figure 2