Co-based soft magnetic thin film for SoC and preparation method of Co-based soft magnetic thin film

Abstract

The invention discloses a Co-based soft magnetic thin film for SoC and a preparation method thereof, and belongs to the technical field of soft magnetic thin films. The soft magnetic thin film comprises a stripe pattern double-layer thin film formed on a substrate, wherein the first layer of stripe thin film is an inclined columnar crystal stripe which is inclined along the length direction of the stripe and forms an included angle alpha 1 with the plane of the substrate; the second layer of stripe film is inclined columnar crystal stripes which are inclined along the length direction of the stripes and are opposite to the first layer of stripe film, and the included angle between the second layer of stripe film and the substrate plane is alpha 2. According to the method, a wedge-shaped structure and a shadow shielding effect are eliminated by adopting a two-step inclined deposition means, a thickness compensation structure is formed, and the problems of non-uniformity and magnetic performance deterioration caused by inclined deposition are solved; during deposition, a stripe-shaped mask plate is adopted, atomic flow incidence is controlled in the stripe length direction, stripe shape anisotropy and inclined columnar crystal magnetic anisotropy are controlled in the same direction, superposition of anisotropic fields is achieved, the resonant frequency and magnetic performance of the thin film are effectively improved, and the high-frequency application range of the thin film is widened.

Description

Technical Field

[0001] This invention belongs to the field of soft magnetic thin film technology, specifically relating to a Co-based soft magnetic thin film for SoC and its preparation method. Background Technology

[0002] The rapid development of next-generation communication technologies has increased public demand for portable, high-performance electronic products. Consequently, electronic products are constantly evolving towards higher frequencies, thinner and lighter designs, smaller sizes, and greater integration. In particular, this has placed higher demands on the magnetic and frequency characteristics of thin-film inductor core materials used in System-on-Chips (SoCs) of electronic products.

[0003] To expand the high-frequency application range of soft magnetic thin films, based on Kittle theory: f r =( γ / 2π)*( H k ( H k +4π M s )) (1 / 2) , ( f r Resonant frequency, γ : gyromagnetic ratio, H k Anisotropic fields M s : saturation magnetization), enhances the in-plane anisotropic field ( H k) is an effective method. Currently, the commonly used methods for inducing in-plane anisotropy are mainly: (1) Applying a magnetic field along the thin film plane. Chinese invention patent CN104465017A discloses a magnetic field-induced CoZrNb thin film and its preparation method. This patent prepares a thin film with in-plane anisotropy by adding a permanent magnet to the back of the substrate to construct a magnetic field and combining it with magnetron sputtering process. However, the external magnetic field often depends on the permanent magnet, the magnetic field control range is narrow and cannot guarantee that the magnetic field lines are uniformly distributed in the thin film, and the constructed in-plane uniaxial anisotropy field is weak. (2) Constructing a thin film with anisotropic shape patterns. Chinese invention patent CN113921216A discloses a soft magnetic thin film with an in-plane oxide / metal alternating stripe structure, which constructs in-plane anisotropy and improves the resonance frequency. However, this method requires photolithography to control the shape of the pattern, and the preparation process is long and not conducive to large-scale production. (3) Applying tensile or compressive stress along the in-plane uniaxial direction of the thin film to induce anisotropy. Chinese invention patent CN102683003A discloses a method for constructing an in-plane anisotropic thin film by providing stress using a substrate with an anisotropic coefficient of thermal expansion. This method has certain limitations. Apart from the substrate disclosed in the patent, common rigid substrates can hardly provide stress to the thin film through deformation. If a flexible substrate is used, the surface of the prepared thin film is very prone to cracking after the external stress is removed, and the magnetic properties will be severely deteriorated. (4) Prepare a thin film containing tilted columnar crystals by tilted deposition. Chinese invention patent CN116397193A discloses a thin film of CoFeB and SiO2 tilted co-sputtering. The tilted sputtering process effectively constructs an in-plane anisotropic field and improves the resonant frequency of the thin film. This method is simple and efficient and compatible with most physical vapor deposition processes, but the following problems still exist: (1) The thin film is grown into a wedge-shaped structure due to the tilting process. When used as a magnetic core, the magnetic field lines are not uniformly bound, which may lead to device failure; (2) The tilting growth causes the easy axis in the plane to be distributed along the direction perpendicular to the incident projection of the evaporation source due to the shape anisotropy, and the shape anisotropy of the tilted columnar crystal is not effectively utilized; (3) The tilting growth produces a large number of serrated structures due to the shadow self-masking effect, which increases the pinning sites and causes magnetic properties such as coercivity to deteriorate.

[0004] Therefore, developing a process for controlling the high-frequency magnetic properties of soft magnetic thin films based on published patents, which has strong compatibility, significantly improved performance, and benefits device reliability, has significant practical application value. Summary of the Invention

[0005] The purpose of this invention is to address the problems existing in the background technology by proposing a Co-based soft magnetic thin film for SoC and its preparation method.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A Co-based soft magnetic thin film for SoC includes a striped patterned bilayer thin film formed on a substrate. The first striped thin film is inclined along the stripe length direction and forms an angle with the substrate plane. α 1. Inclined columnar crystal structure stripe pattern thin film; The second striped film is tilted along the stripe length direction, with the tilt direction opposite to that of the first striped film, and forms an angle with the substrate plane. α 2. Inclined columnar crystal structure stripe pattern thin film.

[0007] Furthermore, α 1= α 2 = 10° - 80°.

[0008] Furthermore, in the first and second striped films, the width of the stripes is 10-100 μm, the length is 5-40 mm, and the spacing between the stripes is 10-100 μm.

[0009] Furthermore, the striped patterned double-layer film has an "arrow-like" interface with a thickness compensation structure.

[0010] Preferably, the substrate is Si.

[0011] Furthermore, the first and second striped thin films are binary alloy soft magnetic thin films with the chemical formula Co. x M 100-x The non-magnetic element M is selected from one of Nb, Zr, Ta, and Ti, and x is the atomic percentage (at. %) of the magnetic element in the binary alloy, where 77.0 ≤ x ≤ 99.9.

[0012] Furthermore, the thickness of the Co-based soft magnetic film is 20 nm-200 nm.

[0013] A method for preparing a Co-based soft magnetic film for SoC involves a two-step tilted electron beam evaporation process combined with a striped pattern mask to prepare a double-layer striped pattern soft magnetic film, thereby obtaining a striped pattern Co-based soft magnetic film for SoC with a thickness compensation structure and an "arrow-like" interface.

[0014] A method for preparing a Co-based soft magnetic thin film for SoC includes the following steps: Step 1. Using electron beam evaporation combined with a striped photomask, at a substrate tilt angle of... α A first thin film with an inclined columnar crystal stripe pattern distributed along the stripe length direction is grown on the sample holder of 1. Step 2. Take the sample obtained in Step 1, rotate the sample 180° in the plane of the sample holder, and adjust the tilt angle of the sample holder to... α2. Using electron beam evaporation combined with a mask, a second layer of striped patterned film with an inclined columnar crystal structure distributed along the stripe length direction is grown on the first layer of striped patterned film to obtain the Co-based soft magnetic film for SoC.

[0015] Furthermore, α 1= α 2 = 10° - 80°.

[0016] Furthermore, in steps 1 and 2, the deposition rate of the electron beam evaporation process is 0.01 nm / s–0.1 nm / s, and the deposition vacuum degree is less than 5 × 10⁻⁶. -5 Pa.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention provides a Co-based soft magnetic thin film for SoC and its preparation method. It employs a two-step tilted deposition method to eliminate wedge structure and shadowing effect, forming a thickness compensation structure and optimizing the non-uniformity and magnetic performance degradation caused by tilted deposition. During deposition, a striped mask is used to control the atomic flow along the stripe length direction, controlling the anisotropy of the stripe shape and the magnetic anisotropy of the tilted columnar crystal in the same direction, realizing the superposition of anisotropic fields, effectively improving the resonant frequency and magnetic performance of the thin film, and broadening its high-frequency application range.

[0018] 2. The present invention provides a Co-based soft magnetic thin film for SoC and its preparation method. The soft magnetic thin film obtained has advantages such as good soft magnetic properties, high initial permeability, high resonant frequency, in-plane uniaxial anisotropy, and strong film uniformity. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the Co-based soft magnetic thin film for SoC of the present invention; wherein (a) is a schematic diagram of the first striped thin film, and (b) is a schematic diagram of the striped double-layer thin film; Figure 2 This is a flowchart illustrating the fabrication process of the Co-based soft magnetic thin film for SoC according to the present invention; Figure 3 The images show the surface morphology of the Co-based soft magnetic thin film for SoC of the present invention; wherein (a) is the scanning electron microscope and atomic force microscope test results of the thin film prepared in the example, and (b) is the scanning electron microscope and atomic force microscope test results of the thin film prepared in Comparative Example 1. Figure 4 The images show cross-sectional morphology of the Co-based soft magnetic thin film for SoC of the present invention; wherein (a) is the scanning electron microscope cross-sectional test result of the thin film prepared in the example, and (b) is the scanning electron microscope cross-sectional test result of the thin film prepared in Comparative Example 1. Figure 5The magnetic spectrum curves of the Co-based soft magnetic thin film for SoC of the present invention are shown below; where (a) is the real part of the complex permeability of Examples 1-7 and Comparative Examples 1-7, (b) is the imaginary part of the complex permeability of Examples 1-7 and Comparative Examples 1-7, and (c) is the statistical representation of the resonant frequencies of Examples 1-7 and Comparative Examples 1-7. Detailed Implementation

[0020] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0021] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, regarding numerical ranges in this invention, it should be understood that the disclosed values ​​are included between the upper and lower limits. Any stated values ​​or smaller ranges within stated ranges should also be included within the scope of this invention.

[0022] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that the following description is merely a preferred embodiment of the present invention and should not be considered as a limitation on the scope of protection of the present invention. Based on a full understanding of the present invention, experimental methods in the following embodiments that do not specify specific conditions are generally performed under conventional conditions or as recommended by the manufacturer. Those skilled in the art can make non-essential modifications to the technical solutions of the present invention, and such modifications should be considered to be included within the scope of protection of the present invention. Example

[0023] This embodiment provides a soft magnetic thin film, comprising a substrate and soft magnetic thin film layer 1 and soft magnetic thin film layer 2 deposited on the substrate. The substrate is made of Si, and soft magnetic thin film layer 1 and soft magnetic thin film layer 2 have the same composition. In this embodiment, the preferred material composition is Co. 90 Nb 10 The thin film was prepared using a two-step tilted electron beam evaporation process combined with a photomask, and contains a thickness-compensating structure, an "arrow-like" interface, and a stripe pattern. Atomic vapor is incident along the length of the stripes.

[0024] The soft magnetic thin film is prepared as follows: (1) The substrate was placed in acetone, ethanol and deionized water for three-step ultrasonic cleaning. Each cleaning step lasted 6 minutes and the cleaning process was repeated twice.

[0025] (2) Place the substrate on the self-made tilted sample holder, with the tilt angle of the sample holder being... α 1. Preferably, it is 30°.

[0026] (3) The mask containing the striped pattern is attached tightly to the growth surface of the substrate. The striped pattern is preferably 60 μm wide, 50 μm apart, and 5 mm long.

[0027] (4) Place the sample holder with the substrate and striped mask on the sample stage of the electron beam evaporation equipment. The equipment vacuum should be better than 5 × 10⁻⁶. -5 Pa.

[0028] (5) The film deposition rate is preferably 0.01 nm / s, and the film thickness is controlled by a quartz crystal film thickness gauge. Considering the bonding strength between the film and the substrate, if the film is too thick, it will fall off due to the influence of internal stress and bonding force. The preferred film thickness is 50 nm.

[0029] (6) When the film has grown to half the preset thickness, remove the sample, rotate the substrate 180° along the sample holder plane, and adjust the tilt angle of the sample holder to... α 2. This embodiment is preferred. α 2. Angle 30° is maintained; continue with subsequent thin film preparation. Flowchart as follows: Figure 2 As shown.

[0030] The surface morphology of thin films was tested using scanning electron microscopy and atomic force microscopy, such as... Figure 3 As shown in (a), a distinct striped pattern and a uniform surface are observed.

[0031] The cross-sectional morphology of thin films was tested using scanning electron microscopy, such as... Figure 4 As shown in (a), a distinct tilted columnar crystal structure, an "arrow-like" interface, and a thickness-compensated structure were observed.

[0032] In contrast, the superiority of the thickness compensation structure and the "arrow-like" interface of the present invention is highlighted. Regarding the process control in the above embodiments, that is, in step (6) of the embodiments, a film of the preset thickness is directly obtained through a one-step tilting deposition method without secondary deposition. The specific implementation method is as follows: This comparative example provides a soft magnetic thin film, comprising a substrate and a soft magnetic thin film layer deposited on the substrate. The substrate is made of Si, and in this comparative example, the preferred material composition is Co. 90 Nb 10 The thin film was prepared by a one-step tilted electron beam evaporation process combined with a photomask, and contained a tilted columnar crystal structure and a stripe pattern. Vapor atoms were incident along the length of the stripes.

[0033] The method for preparing the thin film containing the tilted columnar crystal structure and stripe pattern is as follows: (1) The substrate was placed in acetone, ethanol and deionized water for three-step ultrasonic cleaning. Each cleaning step lasted 6 minutes and the cleaning process was repeated twice.

[0034] (2) Place the substrate on the self-made tilted sample holder, with the tilt angle of the sample holder being... α 1. Preferably, it is 30°.

[0035] (3) The mask containing the striped pattern is attached tightly to the growth surface of the substrate. The striped pattern is preferably 60 μm wide, 50 μm apart, and 5 mm long.

[0036] (4) Place the sample holder with the substrate and striped mask on the sample stage of the electron beam evaporation equipment. The vacuum of the equipment should be better than 5 × 10⁻⁶. -5 Pa.

[0037] (5) The film deposition rate is preferably 0.01 nm / s, and the film thickness is controlled by a quartz crystal film thickness gauge. Considering the bonding strength between the film and the substrate, if the film is too thick, it will fall off due to the influence of internal stress and bonding force. The preferred film thickness is 50 nm.

[0038] The surface morphology of thin films was tested using scanning electron microscopy and atomic force microscopy, such as... Figure 3 As shown in (b), a distinct striped pattern and a jagged structure produced by the shadow occlusion effect were observed.

[0039] The cross-sectional morphology of thin films was tested using scanning electron microscopy, such as... Figure 4 As shown in (b), a distinct tilted columnar crystal structure was observed.

[0040] In contrast, the tilted columnar crystals designed in this invention, distributed along the length of the stripe pattern, have a superimposed effect on the anisotropic field. Adjusting the mask orientation in the above embodiments restricts vapor atoms from incident along the stripe width direction. A thin film containing a thickness-compensating structure and an "arrow-like" interface is prepared using a two-step tilted electron beam evaporation process. Specific implementation details are as follows: This comparative example provides a soft magnetic thin film, comprising a substrate and soft magnetic thin film layer 1 and soft magnetic thin film layer 2 deposited on the substrate. The substrate is made of Si, and soft magnetic thin film layer 1 and soft magnetic thin film layer 2 have the same composition. In the embodiment, the preferred material composition is Co. 90 Nb 10 The thin film was prepared using a two-step tilted electron beam evaporation process combined with a photomask, and contains a thickness-compensating structure, an "arrow-like" interface, and a stripe pattern. Atomic vapor is incident along the width of the stripes.

[0041] The method for preparing the thin film containing a thickness-compensating structure, an "arrow-like" interface, and a stripe pattern is as follows: (1) The substrate was placed in acetone, ethanol and deionized water for three-step ultrasonic cleaning. Each cleaning step lasted 6 minutes and the cleaning process was repeated twice.

[0042] (2) Place the substrate on the self-made tilted sample holder, with the tilt angle of the sample holder being... α 1. Preferably, it is 30°.

[0043] (3) The mask containing the striped pattern is attached tightly to the growth surface of the substrate. The striped pattern is preferably 60 μm wide, 50 μm apart, and 5 mm long.

[0044] (4) Place the sample holder with the substrate and striped mask on the sample stage of the electron beam evaporation equipment. The equipment vacuum should be better than 5 × 10⁻⁶. -5 Pa.

[0045] (5) The film deposition rate is preferably 0.01 nm / s, and the film thickness is controlled by a quartz crystal film thickness gauge. Considering the bonding strength between the film and the substrate, if the film is too thick, it will fall off due to the influence of internal stress and bonding force. The preferred film thickness is 50 nm.

[0046] (6) When the film has grown to half the preset thickness, remove the sample, rotate the substrate 180° along the sample holder plane, and adjust the tilt angle of the sample holder to... α 2. This embodiment is preferred. α With an angle of 30°, continue with the subsequent thin film preparation.

[0047] In contrast, this invention highlights the superiority of the tilted columnar crystals distributed along the length of the stripe pattern in order to superimpose anisotropic fields and the thickness compensation structure in optimizing soft magnetic properties. The mask direction in the above embodiments is adjusted to restrict vapor atoms from incident along the stripe width direction; in step (6) of the embodiment, a film of the preset thickness is directly obtained through a one-step tilted deposition method, without secondary deposition. Specific implementation methods are as follows: This comparative example provides a soft magnetic thin film, comprising a substrate and a soft magnetic thin film layer deposited on the substrate. The substrate is made of Si, and in this comparative example, the preferred material composition is Co. 90 Nb 10 The thin film was prepared by a one-step tilted electron beam evaporation process combined with a photomask, and contained a tilted columnar crystal structure and a stripe pattern. Vapor atoms were incident along the width of the stripes.

[0048] The method for preparing the thin film containing the tilted columnar crystal structure and stripe pattern is as follows: (1) The substrate was placed in acetone, ethanol and deionized water for three-step ultrasonic cleaning. Each cleaning step lasted 6 minutes and the cleaning process was repeated twice.

[0049] (2) Place the substrate on the self-made tilted sample holder, with the tilt angle of the sample holder being... α 1. Preferably, it is 30°.

[0050] (3) The mask containing the striped pattern is attached tightly to the growth surface of the substrate. The striped pattern is preferably 60 μm wide, 50 μm apart, and 5 mm long.

[0051] (4) Place the sample holder with the substrate and striped mask on the sample stage of the electron beam evaporation equipment. The vacuum of the equipment should be better than 5 × 10⁻⁶. -5 Pa.

[0052] (5) The film deposition rate is preferably 0.01 nm / s, and the film thickness is controlled by a quartz crystal film thickness gauge. Considering the bonding strength between the film and the substrate, if the film is too thick, it will fall off due to the influence of internal stress and bonding force. The preferred film thickness is 50 nm.

[0053] In contrast, the superiority of the thin film stripe pattern design of the present invention is highlighted. The process control in the above embodiments, i.e., without adding a mask in step (3) of the embodiment, uses a two-step tilted electron beam evaporation process to prepare a thin film containing a thickness-compensating structure and an "arrow-like" interface. Specific implementation methods are as follows: This comparative example provides a soft magnetic thin film, comprising a substrate and soft magnetic thin film layer 1 and soft magnetic thin film layer 2 deposited on the substrate. The substrate is made of Si, and soft magnetic thin film layer 1 and soft magnetic thin film layer 2 have the same composition. In this comparative example, the preferred material composition is Co. 90 Nb 10 The thin film was prepared by a two-step tilted electron beam evaporation process and contains a thickness-compensating structure.

[0054] The method for preparing the thin film containing the thickness-compensating structure is as follows: (1) The substrate was placed in acetone, ethanol and deionized water respectively for three-step ultrasonic cleaning. Each cleaning step lasted 6 minutes and the cleaning process was repeated twice.

[0055] (2) Place the substrate on the self-made tilted sample holder, with the tilt angle of the sample holder being... α 1. Preferably, it is 30°.

[0056] (3) Place the sample holder with the substrate on the sample stage of the electron beam evaporation equipment, where the equipment vacuum is better than 5 × 10⁻⁶. -5 Pa.

[0057] (4) The film deposition rate is preferably 0.01 nm / s, and the film thickness is controlled by a quartz crystal film thickness gauge. Considering the bonding strength between the film and the substrate, if the film is too thick, it will be affected by internal stress and bonding force, which will cause the film to fall off. The preferred film thickness is 50 nm.

[0058] (5) When the film has grown to half the preset thickness, remove the sample, rotate the substrate 180° along the sample holder plane, and adjust the tilt angle of the sample holder to... α 2. This comparative example is preferred. α With an angle of 30°, continue with the subsequent thin film preparation.

[0059] In contrast, the superiority of the thickness compensation structure, "arrow-like" interface, and stripe pattern design of the present invention is highlighted. Regarding the process control in the above embodiments, a mask is not added in step (3) of the embodiments; in step (6) of the embodiments, a film of the preset thickness is directly obtained through a one-step tilting deposition method, without secondary deposition. Specific implementation methods are as follows: This comparative example provides a soft magnetic thin film, comprising a substrate and a soft magnetic thin film layer deposited on the substrate. The substrate is made of Si, and in this comparative example, the preferred material composition is Co. 90 Nb 10 The thin film was prepared by a one-step tilted electron beam evaporation process and contains a tilted columnar crystal structure.

[0060] The method for preparing the thin film containing the tilted columnar crystal structure is as follows: (1) The substrate was placed in acetone, ethanol and deionized water respectively for three-step ultrasonic cleaning. Each cleaning step lasted 6 minutes and the cleaning process was repeated twice.

[0061] (2) Place the substrate on the self-made tilted sample holder, with the tilt angle of the sample holder being... α 1. Preferably, it is 30°.

[0062] (3) Place the sample holder with the substrate on the sample stage of the electron beam evaporation equipment, where the equipment vacuum is better than 5 × 10⁻⁶. -5 Pa.

[0063] (4) The film deposition rate is preferably 0.01 nm / s, and the film thickness is controlled by a quartz crystal film thickness gauge. Considering the bonding strength between the film and the substrate, if the film is too thick, it will be affected by internal stress and bonding force, which will cause the film to fall off. The preferred film thickness is 50 nm.

[0064] In contrast, to highlight the superiority of the tilted deposition method of the present invention, the process in the above embodiments is adjusted by changing the sample holder used in step (2) to a conventional sample holder; and changing the process in step (5) to a conventional electron beam evaporation process. Specific implementation methods are as follows: This comparative example provides a soft magnetic thin film, comprising a substrate and a soft magnetic thin film layer deposited on the substrate. The substrate is made of Si, and in this comparative example, the preferred material composition is Co. 90 Nb 10 The thin film was prepared by a one-step electron beam evaporation process and contains a vertical columnar crystal structure and stripe pattern.

[0065] The method for preparing the thin film containing a vertical columnar crystal structure and striped pattern is as follows: (1) The substrate was placed in acetone, ethanol and deionized water for three-step ultrasonic cleaning. Each cleaning step lasted 6 minutes and the cleaning process was repeated twice.

[0066] (2) Place the substrate on a standard sample holder with the substrate facing the target.

[0067] (3) Place the mask with striped pattern tightly against the substrate growth surface. The striped pattern is preferably 60 μm wide, 50 μm apart, and 5 mm long.

[0068] (4) Place the sample holder with the substrate on the sample stage of the electron beam evaporation equipment, where the equipment vacuum is better than 5 × 10⁻⁶. -5 Pa.

[0069] (5) The film deposition rate is preferably 0.01 nm / s, and the film thickness is controlled by a quartz crystal film thickness gauge. Considering the bonding strength between the film and the substrate, if the film is too thick, it will be affected by internal stress and bonding force, which will cause the film to fall off. The preferred film thickness is 50 nm.

[0070] In contrast, the thickness compensation structure, "arrow-like" interface, and stripe pattern of the thin film of the present invention are highlighted as having comprehensive advantages. The process in the above embodiments is adjusted by changing the sample holder used in step (2) to a conventional sample holder; changing the process in step (3) by removing the mask; and changing the process in step (5) to a conventional electron beam evaporation process. Specific implementation methods are as follows: This comparative example provides a soft magnetic thin film comprising a substrate and a soft magnetic thin film layer deposited on the substrate. The substrate is made of Si, and in this comparative example, the preferred material composition is Co. 90 Nb 10 The thin film was prepared by a one-step electron beam evaporation process and contains a vertical columnar crystal structure.

[0071] The method for preparing the thin film containing the vertical columnar crystal structure is as follows: (1) The substrate was placed in acetone, ethanol and deionized water for three-step ultrasonic cleaning. Each cleaning step lasted 6 minutes and the cleaning process was repeated twice.

[0072] (2) Place the substrate on a standard sample holder with the substrate facing the target.

[0073] (3) Place the sample holder with the substrate on the sample stage of the electron beam evaporation equipment, where the equipment vacuum is better than 5 × 10⁻⁶. -5 Pa.

[0074] (4) The film deposition rate is preferably 0.01 nm / s, and the film thickness is controlled by a quartz crystal film thickness gauge. Considering the bonding strength between the film and the substrate, if the film is too thick, it will be affected by internal stress and bonding force, which will cause the film to fall off. The preferred film thickness is 50 nm.

[0075] 1. Surface morphology The surface morphology of Examples 1 and Comparative Example 1 was tested using an atomic force microscope (AFM) manufactured by Glampinger in tapping mode. The test results are as follows: Figure 3 As shown.

[0076] The cross-sectional morphology of Examples 1 and Comparative Example 1 was tested using a Zeiss Sigma 360 scanning electron microscope, and the results are as follows. Figure 4 As shown.

[0077] Compared to Comparative Example 1, the embodiment exhibits lower surface roughness and smaller particle size. This highlights the superiority of the thickness compensation structure and reduces surface defects. Furthermore, the embodiment eliminates the serrated structure, reducing pinning sites and optimizing overall magnetic performance.

[0078] 2. Soft magnetic properties The hysteresis loops in two mutually perpendicular directions within the plane of Examples 1-7 were tested using a Lake Shore 8604 vibrating sample magnetometer manufactured by Lake Shore Corporation, and their soft magnetic properties were analyzed. The test results are shown in Table 1.

[0079] Table 1 Comparison of soft magnetic properties between the examples and comparative examples. <![CDATA[Soft magnetic thin film Co 90 Nb 10 > <![CDATA[Coercive force along the easy axis H c∥ (Oe)]]> <![CDATA[Coercive force of hard axis H c⊥ (Oe)]]> <![CDATA[In-plane anisotropy field H k (Oe)]]> Example (two-step inclined deposition along the stripe length direction) 53 12 253 Comparative Example 1 (one-step inclined deposition along the stripe length direction) 71 29 163 Comparative Example 2 (two-step inclined deposition along the stripe width direction) 40 32 15 Comparative Example 3 (one-step inclined deposition along the stripe width direction) 75 68 27 Comparative Example 4 (Two-step tilting deposition process) 21 8.5 102 Comparative Example 5 (One-step tilting deposition process) 41 30.1 168 Comparative Example 6 (Conventional deposition process + stripe pattern) 27 7.5 80 Comparative Example 7 (Conventional Deposition Process) 16 32 35 The results show that the embodiment exhibits lower coercivity compared to Comparative Example 1, indicating that in practical applications, the embodiment demonstrates lower hysteresis loss and higher initial permeability compared to Comparative Example 1, demonstrating that the thickness compensation structure effectively optimizes soft magnetic properties. Furthermore, the embodiment shows a 55% improvement in the in-plane anisotropy field compared to Comparative Example 1, proving that the thickness compensation structure, "arrow-like" interface, and striped patterned thin film constructed in the embodiment have greater potential for high-frequency applications.

[0080] The in-plane anisotropy fields of Comparative Examples 2 and 3 are lower than those of the Examples and all the Comparative Examples, indicating that oblique incidence along the fringe width direction has a negative optimization effect on high-frequency applications.

[0081] Compared with Comparative Example 4, the Example 1 has a higher in-plane anisotropic field, demonstrating the effectiveness of the stripe pattern construction in improving the anisotropic field; compared with Comparative Example 5, the Example 1 has superior overall soft magnetic properties, demonstrating the advantages of the stripe pattern and thickness compensation structure; compared with Comparative Example 6, the Example 1 has a 210% improvement in anisotropic field, demonstrating the effectiveness of the two-step tilting deposition process; compared with Comparative Example 7, the Example 1 has a 622% improvement in anisotropic field, demonstrating the combined advantages of the two-step tilting deposition process and the stripe pattern.

[0082] 3. High-frequency magnetic properties The magnetic spectrum of the thin film along the easy axis was measured using an Agilent Technologies N5227A vector network analyzer via the single-ended short-circuit microstrip line method. The test results are as follows: Figure 5 As shown.

[0083] The embodiments show significant advantages in resonant frequencies compared to comparative examples 1-7, highlighting the advanced nature and effectiveness of the embodiments in controlling the high-frequency application range of magnetic thin films.

[0084] The lowest resonance frequencies in Comparative Examples 2 and 3 demonstrate the rationality of the distribution of tilted columnar crystals along the stripe length direction in this invention. It also shows that the construction of the thickness compensation structure, the "arrow-like" interface, and the selection of tilted deposition and striping synergistic control of the stripe pattern in this invention are not simply superimposed using existing processes. It is necessary to control the anisotropy of the crystal structure and the anisotropy direction of the stripe pattern to be in the same direction in order to achieve comprehensive performance optimization.

[0085] In summary, the thickness-compensated structure, "arrow-like" interface, and stripe pattern of the embodiments effectively improve the in-plane anisotropic field of the thin film by introducing shape anisotropy, thus broadening the working frequency range of the thin film; the thickness compensation method effectively reduces defects, refines grains, and solves the problem of insufficient high-frequency magnetic performance caused by single-step tilting deposition process.

Claims

1. A Co-based soft magnetic thin film for SoC, characterized in that, This includes a striped patterned bilayer film formed on a substrate, wherein the first striped film is inclined along the stripe length direction and forms an angle with the substrate plane. α 1. Tilted columnar crystal striations; The second striped film is tilted along the stripe length direction, with the tilt direction opposite to that of the first striped film, and forms an angle with the substrate plane. α 2. Tilted columnar crystal striations.

2. The Co-based soft magnetic thin film for SoC according to claim 1, characterized in that, α 1= α 2=10°-80°。 3. The Co-based soft magnetic thin film for SoC according to claim 1, characterized in that, In the first and second striped films, the width of the stripes is 10-100 μm, the length is 5-40 mm, and the spacing between the stripes is 10-100 μm.

4. The Co-based soft magnetic thin film for SoC according to claim 1, characterized in that, The striped double-layer film has an "arrow-like" interface with a thickness compensation structure.

5. The Co-based soft magnetic thin film for SoC according to claim 1, characterized in that, The substrate is Si.

6. The Co-based soft magnetic thin film for SoC according to claim 1, characterized in that, The first and second striped thin films are binary alloy soft magnetic thin films with the chemical formula Co. x M 100-x M is selected from one of Nb, Zr, Ta, and Ti, and 77.0 ≤ x ≤ 99.

9.

7. The Co-based soft magnetic thin film for SoC according to claim 1, characterized in that, The thickness of the Co-based soft magnetic film is 20 nm-200 nm.

8. A method for preparing a Co-based soft magnetic thin film for SoC, comprising a two-step tilted electron beam evaporation process combined with a striped pattern mask to prepare a double-layer striped pattern soft magnetic thin film.

9. A method for preparing a Co-based soft magnetic thin film for SoC, characterized in that, Includes the following steps: Step 1. Using electron beam evaporation combined with a striped photomask, at a substrate tilt angle of... α The first layer of inclined columnar crystal stripes distributed along the stripe length direction is grown on the sample holder of 1. Step 2. Take the sample obtained in Step 1, rotate it 180° along the plane of the sample holder, and adjust the tilt angle of the sample holder to... α 2. Using an electron beam evaporation process combined with a mask, a second layer with inclined columnar crystalline stripes distributed along the stripe length direction is grown on the first stripe film to obtain the Co-based soft magnetic film for SoC.

10. The method for preparing a Co-based soft magnetic thin film for SoC according to claim 9, characterized in that, In steps 1 and 2, the deposition rate of the electron beam evaporation process is 0.01 nm / s–0.1 nm / s, and the deposition vacuum is less than 5 × 10⁻⁶. -5 Pa.

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