A preparation method of femn alloy nano film with strong exchange bias effect

Abstract

The invention discloses a preparation method for Fe Mn alloy nanometer thin films with the high exchange biasing effect and belongs to the field of metal nanometer thin film preparation. Fe Mn alloy freedom clusters with the size being of the nanometer scale are prepared firstly, then the processes of collision, condensation and concretion are conducted in cavities of the clusters, and the Fe Mn alloy freedom clusters changes into Fe Mn alloy supporting clusters; and the Fe Mn alloy supporting clusters are attached to the surfaces of clean and smooth underlayers, assembling of the Fe Mn alloy clusters is completed on the surfaces of the underlayers, and thus the Fe Mn alloy nanometer thin films with nano-structures are obtained. According to the preparation method for the Fe Mn alloy nanometer thin films with the high exchange biasing effect, by adopting the cluster beam sedimentation method, the clusters are deposited into the Fe Mn alloy nanometer thin films in a soft landing mode, generation of inner stress is reduced, cluster assembling is achieved, a particular structure is obtained, and selection and control of the sizes and components of nanometer particles are achieved; and the prepared Fe Mn alloy nanometer thin films have the advantages of being high in exchange biasing effect, smooth and compact and high in density.

Description

technical field [0001] The invention relates to a preparation method of FeMn alloy nano film with strong exchange bias effect, belonging to the field of metal nano film preparation. Background technique [0002] The exchange bias effect was first discovered by Meikleijohn and Bean in the core-shell structure of Co in 1956. After the ferromagnetic (FM) / antiferromagnetic (AFM) interface is cooled in an external magnetic field from a temperature higher than the antiferromagnetic Neel temperature to a low temperature, the hysteresis loop of the ferromagnetic layer will deviate from the origin along the direction of the magnetic field, and the offset is determined by is called the exchange bias field. The exchange bias effect is widely used in the fields of low-power memory and spintronic devices, spin valve giant magnetoresistance devices and magnetic recording. The exchange bias effect mainly exists in the ferromagnetic (FM) / antiferromagnetic (AFM) bilayer film with FeMn allo...

AI Technical Summary

Problems solved by technology

There are certain defects in the preparation of alloy films by physical methods. The process of preparing alloy films by PLD method is complicated, and the size and thickness of film growth cannot be controlled during the growth process.

Although the operation process of alloy thin film prepared by magnetron sputtering is relatively simple, the size and thickness of the film cannot be controlled during the growth process.

The preparation of alloy thin films by MBE method is more complicated, the growth cycle is too long, and the size and thickness of the thin films cannot be controlled during the growth process.

[0005] Chemical methods to prepare thin films also have drawbacks

Due to the limitations of the preparation process, the first method of preparation cannot reach the nanometer size of the film; although the second method can effectively overcome the limitation of the film size, the voltage and current of the reaction conditions during the preparation of the film may be unstable, resulting in the preparation of nanomaterials. Inhomogeneity affects performance; the third process can also effectively overcome the limitation of film size, but because it usually has certain requirements for raw materials, products and reaction types, it cannot meet the requirements for preparing FeMn alloy nano film

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