Vertical magnetic anisotropic multi-layer film

Abstract

The invention discloses a vertical magnetic anisotropic multi-layer film [Ni(x) / Co2Mz(y)]n of which the easily magnetized axis direction is vertical to a film plane, belongs to the field of magnetic materials. The vertical magnetic anisotropic multi-layer film is characterized in that: Co2MZ is a semimetal Heusler alloy component with a structure of L21, B2 or A2; M may be an element of Fe, Cr, Mn and the like; Z may be the element of Al, Si, Ge, B and the like; the thicknesses x and y of each layer of films are that: x is greater than 0.6 nm and smaller than 20 nm; y is greater than 0.4 nm and smaller than 5 nm; and the repeat number n of the periodic structure of the [Ni(x) / Co2Mz(y)]n is greater than 2 and smaller than 20. The vertical magnetic anisotropic multi-layer film has the advantages that: the film has a high vertical magnetic anisotropic field, capability of adjusting a coercive force by controlling the thickness of an Ni layer and a Co2MZ layer, and the coercive force remarkably lower than the coercive force of a traditional vertical magnetic anisotropic multi-layer film, so the film can be used as a ferromagnetic layer in a vertical spin valve or a magnetic tunnel junction, can overcome magnetic curliness under a small size and a vortex magnetic domain structure in application, has adjustable coercive force and can meet the use requirements of a magnetic sensor ora storage with super high sensitivity and storage density.

Description

Technical field [0001] The invention belongs to the field of magnetic materials, and particularly relates to a new type of perpendicular magnetic anisotropy multilayer film, the direction of the easy magnetization axis is perpendicular to the film plane. Background technique [0002] The size of the information storage unit determines the level of storage density. In recent years, the size of the storage unit has been decreasing, which has caused the magnetic storage density to continue to increase, so the magnetic storage technology has developed rapidly. The magnetization direction of the magnetic storage film is divided into parallel to the film surface and perpendicular to the film surface, that is, in-plane magnetic anisotropic thin film and perpendicular magnetic anisotropic thin film. At present, the magnetization directions of the widely used magnetic metal nano-films are all in-plane magnetic anisotropy. When the size of this kind of film is reduced to sub-micron or less...

AI Technical Summary

Problems solved by technology

But so far, the performance of all perpendicular magnetic anisotropic films is not very ideal, specifically in that their coercive force is too high, it is difficult to flip, and they are not suitable for computer readout heads or magnetic field sensors.