Magnetic sandwich material based on nanocrystalline soft magnetic thin film and its preparing method

Abstract

The invention discloses a novel giant magnetoresistance sandwich material. This material is separated by a non-magnetic metal layer between the first ferromagnetic layer and the second ferromagnetic layer. It is characterized in that one of the first ferromagnetic layer and the second ferromagnetic layer is a nanocrystalline magnetic film, and the other It is a polycrystalline magnetic film; the nanocrystalline magnetic film applied to this magnetic sandwich material includes three nanocrystalline soft magnetic films with superior properties: cobalt niobium zirconium CoNbZr, cobalt iron boron CoFeB and cobalt manganese boron CoMnB, and polycrystalline The films are mainly three magnetic films of cobalt Co, cobalt-iron CoFe and permalloy NiFe; the non-magnetic isolation layer is copper Cu and other noble metal materials. The material has an extremely thin overall thickness (about 10nm), large magnetoresistance effect (above 10%), stable single domain state, excellent switching characteristics, and the uniformity deviation of the switching field is less than 8%. Potential new storage materials.

Description

technical field [0001] The invention belongs to the technical field of information storage, and particularly relates to the preparation technology of a novel high-performance giant magnetoresistance material used in an ultra-high-density non-volatile magnetic memory (MRAM). Background technique [0002] In spintronic devices such as giant magnetoresistive heads, nonvolatile magnetic memories, and spin transistors, magnetic information is transmitted from one end of the device to the other via mesomagnets (nanoscale magnetic units). This process requires mesoscopic magnets to "encode" magnetic information into itinerant electron spin channels and then rapidly read them out. This decoding process can be controlled by remagnetizing the mesoscopic magnet, so that the realization of the function of the spintronic device can be controlled by the change of the external magnetic field. At present, the core mesoscopic magnet component of spintronic devices is the "ferromagnetic laye...

AI Technical Summary

Problems solved by technology

As the storage density of MRAM devices increases to Gb / in 2 , the magnetic sandwich unit is required to reach the submicron / nanoscale (100nm) in terms of length and width. Under such a small scale, the performance of the magnetic sandwich material based on the polycrystalline magnetic film undergoes profound changes: (a) interlayer magnetostatic coupling Significantly enhanced, the flip characteristics become worse, and the magnetoresistance effect is reduced; (b) the magnetic unit has a complex domain structure, which affects data security; (c) the uniformity of the large-density memory cell is poor, and the flip magnetic field of the storage bit has a deviation of more than 15%, And if the memory cell size of the magnetoresistive element is at the submicron / nano level, the deviation will become more obvious

These problems seriously hinder the further development of spintronic devices and become the bottleneck of the industrialization of MRAM devices

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