MAGNETIC TUNNEL JUNCTION, MAGNETORESISTIVE RANDOM ACCESS MEMORY, CHIP, AND PREPARATION METHOD FOR MAGNETIC TUNNEL JUNCTION

摘要

A preparation method for a magnetic tunnel junction (MTJ), and the MTJ and a magnetoresistive random access memory. The MTJ comprises: a fixed ferromagnetic layer (11), a free ferromagnetic layer (12), and a magnetic tunnel barrier (13) provided between the fixed ferromagnetic layer (11) and the free ferromagnetic layer (12); a side surface of the free ferromagnetic layer (12) and a surface opposite to the fixed ferromagnetic layer (11) is wrapped by means of the magnetic tunnel barrier (13), or, the magnetic tunnel barrier (13) covers a side surface of the fixed ferromagnetic layer (11) and a surface opposite to the free ferromagnetic layer (12), so that the free ferromagnetic layer (12) is more effectively separated from the fixed ferromagnetic layer (11), and the yield of the MTJ is improved. Furthermore, it is not necessary to form a vertical contour of the MTJ by using an ion or plasma etching method, the difficulty of preparation process is reduced, and the scalability of an MTJ array is improved.