A magnetoresistance sensor based on Kagome semi-metal material and its preparation method

Abstract

The invention discloses a magnetoresistance sensor based on Kagome semi-metal material and a preparation method thereof, which relates to the technical field of magnetoresistance sensor. The magnetoresistance sensor comprises a substrate, an isolation layer, a Kagome semi-metal material layer and a soft magnetic adjacent layer. The Kagome semi-metal material layer is a Wheatstone bridge pattern. The Kagome semi-metal material layer and the soft magnetic adjacent layer are formed on the substrate from bottom to top. The bottom and top of the Kagome semi-metal material layer are both provided with an isolation layer, and the Kagome semi-metal material layer is provided with a metal electrode. The invention greatly improves the sensitivity and linearity while ensuring low power consumption, small volume and high integration. In addition, the invention also has the technical advancement of integration with semiconductor processes.

Description

Technical Field

[0001] The present invention belongs to the technical field of magnetoresistive sensors, and in particular relates to the technical field of magnetoresistive sensors based on Kagome semi-metal materials and preparation methods thereof. Background Art

[0002] With the rapid advancement of science and technology and the in-depth development of the information society, traditional industries such as industry, agriculture and information industry are experiencing a rapid transformation from manual operation to artificial intelligence and precision operation mode. During this transformation process, the demand for smart devices has risen sharply, which has also led to a surge in demand for smart monitoring sensors. However, with the increasing complexity of the working environment, newer requirements have been put forward for the sensitivity and range of sensors.

[0003] Magnetoresistive sensors based on the anisotropic magnetoresistance (AMR) effect have been widely used in the fields of consumer electronics, gaming, medical, security, vehicle navigation, etc. However, due to the limitations of sensitivity and linearity, traditional AMR magnetoresistive sensors are limited in applications in certain fields that require high sensitivity and a large range. The traditional AMR magnetoresistive sensor structure includes a substrate / isolation layer / thin film material layer / isolation layer, and the thin film material layer is generally composed of permalloys such as Ni, Fe, and Co. In order to improve the sensitivity, the thickness of the permalloy material layer needs to be increased, which is not conducive to device integration.

[0004] Therefore, how to improve the sensitivity and linearity of the AMR magnetoresistive sensor while ensuring the miniaturization of the device has become a problem that needs to be solved urgently. Summary of the invention

[0005] In view of the problems existing in the background technology, the purpose of the present invention is to achieve high integration of the device while ensuring that the device has higher sensitivity and larger range than the traditional AMR magnetoresistive sensor. In order to solve the above technical problems, the present invention provides a magnetoresistive sensor based on Kagome semi-metal material and a preparation method thereof:

[0006] In order to achieve the above-mentioned purpose, the present invention specifically adopts the following technical solutions:

[0007] A magnetoresistive sensor based on Kagome semi-metal material, characterized in that the magnetoresistive sensor comprises a substrate, an isolation layer, a Kagome semi-metal material layer and a soft magnetic adjacent layer.

[0008] Furthermore, the Kagome semi-metal material layer and the soft magnetic adjacent layer are sequentially formed on the substrate from bottom to top, and an isolation layer is provided on the top and bottom of the Kagome semi-metal material layer.

[0009] Furthermore, the Kagome semi-metal material layer is in the shape of a Wheatstone bridge.

[0010] Furthermore, the Kagome semi-metal material layer is provided with a metal electrode.

[0011] Furthermore, the material of the Kagome semi-metal material layer is cobalt indium sulfide (Co3In2S2) or nickel indium sulfide (Ni3In2S2) or iron-tin alloy (Fe3Sn2) or manganese-tin alloy (Mn3Sn) or the like.

[0012] Furthermore, the thickness of the Kagome semi-metal material film is 1nm-100nm.

[0013] Furthermore, the material of the soft magnetic adjacent layer is cobalt iron silicon boron (CoFeSiB), cobalt zirconium niobium (CoZrNb), cobalt tantalum zirconium (CoTaZr) or iron-based alloy (FeSi), etc., which is used to provide a stable lateral bias field, which helps to enhance the sensitivity and linearity of the sensor.

[0014] Furthermore, the thickness of the soft magnetic adjacent layer film is 10 nm-10 μm.

[0015] Furthermore, the material of the isolation layer is zinc oxide (ZnO), aluminum oxide (Al2O3), nickel oxide (NiO), magnesium oxide (MgO), silicon dioxide (SiO2) or other non-magnetic metal oxides, etc., which are used to improve interface electron scattering, reduce material resistance, and improve AMR film effect.

[0016] Furthermore, the isolation layer film has a thickness of 5nm-10μm.

[0017] In order to solve the above problems, the present invention also provides a method for preparing a magnetoresistive sensor based on a Kagome semi-metal material, comprising the following steps:

[0018] Cleaning the substrate;

[0019] An isolation layer, a Kagome semi-metal material layer, and an isolation layer are grown from bottom to top on the front side of the substrate, and these three layers are photolithographically formed into a Wheatstone bridge pattern;

[0020] Growing a metal electrode on the Kagome semi-metal material layer;

[0021] growing a soft magnetic adjacent layer on the uppermost isolation layer;

[0022] The device is annealed to complete the device preparation.

[0023] In summary, compared with the existing inventions, the present invention has the following beneficial effects:

[0024] The present invention provides a magnetoresistive sensor based on Kagome semi-metallic material, which has a simple preparation method and can be mass-produced. It is widely used in the fields of geomagnetic detection, aerospace, medical surgery navigation, autonomous robot control, etc. It can directly measure the magnitude of the magnetic field and can also calculate the angle or current in combination with an algorithm, and has a wide range of applications.

[0025] The present invention greatly improves sensitivity and linearity while ensuring low power consumption, small size and high integration; in addition, the present invention also has the technical advancement of integration with semiconductor technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings described herein are used to provide further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0027] in:

[0028] Figure 1 is a schematic diagram of a magnetoresistive sensor of the Kagome semi-metal material of the present invention;

[0029] Figure 2 It is a graphic schematic diagram of Kagome's semi-metallic material layer;

[0030] Figure 3 It is a flow chart of the method for preparing the magnetoresistive sensor of the Kagome semi-metal material of the present invention. DETAILED DESCRIPTION

[0031] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer and more understandable, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0032] This embodiment provides a magnetoresistive sensor based on Kagome semi-metal material, including a substrate, an isolation layer, a Kagome semi-metal material layer and a soft magnetic adjacent layer;

[0033] The shape of the Kagome semi-metal material layer is a Wheatstone bridge;

[0034] The Kagome semi-metal material layer and the soft magnetic adjacent layer are formed on the substrate from bottom to top, and an isolation layer is provided at the bottom and top of the Kagome semi-metal material layer;

[0035] The Kagome semi-metal material layer is provided with a metal electrode.

[0036] Specific reference Figure 1The layer labeled 1 is the substrate, the layer labeled 2 is the Kagome semi-metal material layer, and the layer labeled 3 is the soft magnetic adjacent layer.

[0037] In this example, the Kagome semi-metal material layer is made of cobalt indium sulfide (Co3In2S2) with a material thickness of 40nm; the isolation layer is made of nickel oxide (NiO) with a material thickness of 5nm; the soft magnetic adjacent layer is made of cobalt iron silicon boron (CoFeSiB) with a material thickness of 20nm; and the substrate is made of silicon (Si) wafer.

[0038] The specific preparation method is as follows:

[0039] Step S1: placing the silicon wafer in an acetone solution for 10 minutes of ultrasonic cleaning; then, switching to an ethanol solution for further ultrasonic cleaning for 10 minutes; finally, performing ultrasonic cleaning in deionized water for 10 minutes and blowing the substrate dry, thereby obtaining a clean silicon substrate;

[0040] Step S2: Photolithography is performed on the clean silicon wafer obtained in step 1, and the pattern is Figure 2 Wheatstone bridge diagram;

[0041] Step S3: Using magnetron sputtering method, grow NiO / Co3In2S2 / NiO material layers from bottom to top on the pattern obtained in step 2, and the thicknesses are 5nm, 40nm, and 5nm respectively. Among them, Co3In2S2 is the Kagome semi-metal material layer, and the two layers of NiO are isolation layers;

[0042] Step S4: The device is subjected to secondary photolithography and a conductive metal electrode is prepared;

[0043] Step S5: growing a CoFeSiB material layer with a thickness of 20 nm on the device obtained in step 4 by magnetron sputtering;

[0044] Step S6: annealing the device to complete the preparation.

[0045] At room temperature, the magnetoresistance change rate of the magnetoresistance sensor can reach 4.0%, and the saturation magnetic field is ±600e.

[0046] The present invention is described above by way of example in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as various non-substantial improvements are made using the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A magnetoresistive sensor based on Kagome semi-metal material, characterized in that: The magnetoresistive sensor comprises a substrate, an isolation layer, a Kagome semi-metal material layer and a soft magnetic adjacent layer; The Kagome semi-metal material layer and the soft magnetic adjacent layer are sequentially formed on the substrate from bottom to top, and an isolation layer is provided on the top and bottom of the Kagome semi-metal material layer; The Kagome semi-metal material layer is in the shape of a Wheatstone bridge; The Kagome semi-metal material layer is provided with a metal electrode.

2. The magnetoresistive sensor based on Kagome semi-metal material according to claim 1, characterized in that: The material of the Kagome semi-metal material layer is cobalt indium sulfide or nickel indium sulfide or iron-tin alloy or manganese-tin alloy with anisotropic magnetoresistance effect; the thickness is 1nm-100nm.

3. The magnetoresistive sensor based on Kagome semi-metal material according to claim 1, characterized in that: The material of the isolation layer is zinc oxide, aluminum oxide, nickel oxide, magnesium oxide, silicon dioxide or other non-magnetic metal oxides, etc.; the thickness is 5nm-10μm.

4. The magnetoresistive sensor based on Kagome semi-metal material according to claim 1, characterized in that: The material of the soft magnetic adjacent layer is cobalt-iron-silicon-boron, cobalt-zirconium-niobium, cobalt-tantalum-zirconium or iron-based alloy, etc.; the thickness is 10nm-10μm.

5. A method for preparing a magnetoresistive sensor based on a Kagome semi-metal material, used for preparing the magnetoresistive sensor according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1, cleaning the substrate; S2, growing an isolation layer, a Kagome semi-metal material layer, and an isolation layer from bottom to top on the front side of the substrate, and photolithography these three layers into a Wheatstone bridge pattern; S3, growing a metal electrode on the Kagome semi-metal material layer; S4, growing a soft magnetic adjacent layer on the uppermost isolation layer; S5. Anneal the device to complete the preparation of the device.

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