Magnet device and magnetron sputtering cathode with reduced edge magnetic leakage

Abstract

The application provides a magnet device and a magnetron sputtering cathode with reduced edge magnetic leakage, and relates to the technical field of magnetron sputtering. By adjusting the total residual magnetism ratio of the inner magnet and the outer magnet, the magnetic field distribution is improved, the edge magnetic leakage is reduced, the target material utilization is improved, the chamber pollution and the equipment maintenance frequency are reduced, and finally the use cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of magnetron sputtering, in particular to a magnet device and a magnetron sputtering cathode with reduced edge magnetic leakage. BACKGROUND

[0002] The magnet device is arranged inside the magnetron sputtering cathode with reduced edge magnetic leakage, and generally includes an inner magnet, an outer magnet and a magnetic yoke. The inner magnet and the outer magnet are arranged above the magnetic yoke. The polarities of the inner magnet and the outer magnet are opposite, for example, the inner magnet is S level upward, and the outer magnet is N level upward. The design of the magnet device determines the magnetic field distribution. The magnetic field distribution is an important factor affecting the target material utilization rate and the film coating quality. The target surface magnetic induction intensity (i.e. the component of the magnetic induction intensity on the surface of the target material, which can be represented by B / / ) mainly determines the etching or sputtering degree of the target material. The greater the target surface magnetic induction intensity, the greater the electron concentration, and the greater the etching or sputtering degree of the target material. The target surface magnetic induction intensity mainly distributes in two arcs on the surface of the target material. The space of the two arcs determines the size of the target material sputtering area and the spatial dispersion degree of the target material sputtering particle movement. However, there is a magnetic leakage phenomenon (referred to as edge magnetic leakage) on both sides of the two arc distributions, which is common in the design of conventional magnetron sputtering cathodes. Figure 1 As shown in the figure, the horizontal coordinate represents the distance x (unit: mm) of the target material of the rotary cathode (the surface of the target material is circular), and the vertical coordinate represents the target surface magnetic induction intensity B / / (unit: G). The edge magnetic leakage increases the spatial dispersion degree of the target material sputtering particle movement, which causes the following disadvantages: on the one hand, the edge magnetic leakage will cause the magnetic flux utilization rate of the magnet device to decrease, and will lead to the decrease of the sputtering rate of the main sputtering area of the target material, so as to reduce the effective sputtering amount of the target material to the substrate, and further to reduce the target material utilization rate; on the other hand, the edge magnetic leakage will cause the target material particles to be easily sputtered to other parts in the vacuum chamber, causing the pollution of the vacuum chamber, interfering with the surrounding equipment, and further increasing the equipment maintenance frequency and use cost.

[0003] At present, there is no effective technical solution to the above problems. SUMMARY

[0004] The purpose of the present application is to provide a magnet device and a magnetron sputtering cathode with reduced edge magnetic leakage, which improves the target material utilization rate and reduces the pollution of the chamber, thereby reducing the equipment maintenance frequency and use cost.

[0005] The application provides a magnet device, which comprises an inner magnet, an outer magnet and a magnetic yoke, the inner magnet and the outer magnet are arranged above the magnetic yoke, the inner magnet is arranged on the inner side of the outer magnet, the polarity of the inner magnet and the outer magnet on the upward side is opposite, the ratio of the total residual magnetism of the inner magnet to the total residual magnetism of the outer magnet is greater than or equal to 1.3, and the total residual magnetism refers to the product of the residual magnetic flux density of the magnet and the volume of the magnet.

[0006] Through the above scheme, the problems of serious edge magnetic leakage, low target material utilization rate and chamber pollution caused by the magnet device in the prior art are solved.

[0007] Optionally, the ratio of the total residual magnetism of the inner magnet to the total residual magnetism of the outer magnet ranges from 2 to 4.

[0008] Through the above scheme, the magnetic field distribution is further improved, and the target material utilization rate is improved.

[0009] Optionally, the inner magnet and the outer magnet are cuboids.

[0010] Optionally, the total height and the residual magnetic flux density of the inner magnet and the outer magnet are the same, and the ratio of the total width of the inner magnet to the total width of the outer magnet is greater than or equal to 1.3.

[0011] Through the above scheme, specific size ratio relationships are provided, and the magnetic field distribution is further improved.

[0012] Optionally, the total volume of the inner magnet and the outer magnet is the same, and the ratio of the residual magnetic flux density of the inner magnet to the residual magnetic flux density of the outer magnet is greater than or equal to 1.3.

[0013] Optionally, the total height of the inner magnet and the outer magnet is the same, the ratio of the total width of the inner magnet to the total width of the outer magnet is equal to 1.5, the ratio of the residual magnetic flux density of the inner magnet to the residual magnetic flux density of the outer magnet is equal to 1.2, and the ratio of the total residual magnetism of the inner magnet to the total residual magnetism of the outer magnet is equal to 1.8.

[0014] Through the above scheme, specific size, magnetic flux density and total residual magnetism ratio values are provided, and the magnetic field distribution is further improved.

[0015] Optionally, the total width of the inner magnet and the outer magnet is the same, the ratio of the total height of the inner magnet to the total height of the outer magnet is equal to 1.2, the ratio of the residual magnetic flux density of the inner magnet to the residual magnetic flux density of the outer magnet is equal to 1.3, and the ratio of the total residual magnetism of the inner magnet to the total residual magnetism of the outer magnet is equal to 1.56.

[0016] In a second aspect, the application provides a magnetron sputtering cathode with reduced edge magnetic leakage, comprising the magnet device of any one of the preceding.

[0017] Optionally, the magnetron sputtering cathode with reduced edge magnetic leakage is a planar cathode.

[0018] Optionally, the magnetron sputtering cathode with reduced edge magnetic leakage is a rotary cathode.

[0019] As can be seen from the above, the magnet device and the magnetron sputtering cathode with reduced edge magnetic leakage provided by the application improve the magnetic field distribution by adjusting the total residual magnetism ratio of the inner magnet and the outer magnet, reduce the edge magnetic leakage, thereby improving the target material utilization rate, reducing the chamber pollution and the equipment maintenance frequency, and ultimately reducing the use cost.

[0020] Other features and advantages of the application will be set forth in the following description, and in part will become apparent from the description, or can be learned by practice of the application. The objects and other advantages of the application will be realized and attained by the structure particularly pointed out in the written description and claims. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 A schematic diagram of the target surface magnetic induction intensity effect of the prior art magnet device.

[0022] Figure 2 A first schematic diagram of the target surface magnetic induction intensity effect of the magnet device provided by the embodiment of the application.

[0023] Figure 3 A second schematic diagram of the target surface magnetic induction intensity effect of the magnet device provided by the embodiment of the application.

[0024] Figure 4 A third schematic diagram of the target surface magnetic induction intensity effect of the magnet device provided by the embodiment of the application.

[0025] Figure 5 A fourth schematic diagram of the target surface magnetic induction intensity effect of the magnet device provided by the embodiment of the application.

[0026] Figure 6 A fifth schematic diagram of the target surface magnetic induction intensity effect of the magnet device provided by the embodiment of the application.

[0027] Figure 7 A schematic diagram of the structure of the planar cathode provided by the embodiment of the application.

[0028] Figure 8 A schematic diagram of the structure of the rotary cathode provided by the embodiment of the application.

[0029] REFERENCE SIGNS: 10, inner magnet; 20, outer magnet; 30, magnet yoke; 40, target material. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work fall within the scope of protection of the present application.

[0031] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and should not be understood as indicating or implying relative importance.

[0032] Please refer to Figures 2-8 The present application provides a magnet device and a magnetron sputtering cathode that reduces edge magnetic leakage, thereby improving target material utilization, reducing chamber contamination, and thus reducing equipment maintenance frequency and usage costs.

[0033] The present application provides a magnet device, which includes an inner magnet 10, an outer magnet 20 and a yoke 30. The inner magnet 10 and the outer magnet 20 are arranged above the yoke 30, and the inner magnet 10 is arranged on the inner side of the outer magnet 20 (generally, there are two outer magnets 20 and at least one inner magnet 10, and the two outer magnets 20 are respectively arranged on the left and right sides of the inner magnet 10). The polarities of the inner magnet 10 and the outer magnet 20 facing upward are opposite, and the ratio of the total remanent magnetism of the inner magnet 10 to the total remanent magnetism of the outer magnet 20 is greater than or equal to 1.3. The total remanent magnetism refers to the product of the residual magnetic flux density of the magnet and the volume of the magnet.

[0034] Specifically, the inner magnet 10 and the outer magnet 20 in the magnet device form a specific magnetic field distribution above the surface of the target material 40 through their relative positions and opposite polarities, which guides the movement of electrons in the plasma to achieve sputtering of the target material 40. By controlling the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 and ensuring that the ratio is greater than or equal to 1.3, the contribution of the inner magnet 10 to the central region magnetic flux can be enhanced. This enhanced central magnetic flux force can more effectively constrain the magnetic field lines to concentrate above the main sputtering area of the target material 40, inhibiting the diffusion of the magnetic field to the edge region. The strength of the magnetic field lines in the edge region is reduced, i.e. the edge leakage is reduced, which allows more magnetic flux to concentrate on the effective sputtering track of the target material 40, improves the utilization efficiency of the magnetic flux, thereby increasing the sputtering rate and total amount of the target material 40 in this area and improving the overall utilization rate of the target material 40. At the same time, the weakening of the edge magnetic field also reduces the movement and diffusion of sputtering particles to other non-target material 40 components in the vacuum chamber, reducing the degree of contamination of these components by sputtering particles. Therefore, by adjusting the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20, the present scheme improves the magnetic field distribution and solves the problem of edge leakage in the prior art.

[0035] The present scheme finds through multiple magnetic field simulation that when the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 is greater than or equal to 1.3, the suppression effect of the edge leakage is significant; when the ratio is less than 1.3, the suppression effect of the edge leakage is not obvious, i.e. the edge leakage level is comparable to that of the magnet device in the prior art (i.e. the magnet device before improvement in the following text), therefore, the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 is limited to be greater than or equal to 1.3.

[0036] The scheme of the present application is implemented as follows: the inner magnet 10 and the outer magnet 20 are both rectangular magnetic blocks, the inner magnet 10 is located inside the two outer magnets 20, as shown in Figure 7 The polarity of the side of the inner magnet 10 facing the target material 40 is set to S pole, and the polarity of the side of the outer magnet 20 facing the target material 40 is set to N pole. The size and material grade of the inner magnet 10 are selected so that the product of the residual magnetic flux density and the volume, i.e. the total residual magnetism, is greater than or equal to 1.3 times the product of the residual magnetic flux density and the volume, i.e. the total residual magnetism, of the outer magnet 20. For example, this ratio can be achieved by selecting a material with higher residual magnetic flux density for the inner magnet 10, or by designing the inner magnet 10 to have a relatively larger volume, which is not specifically limited here.

[0037] In some embodiments, the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 is in the range of 2-4.

[0038] Specifically, the present application further improves the magnetic field distribution of the magnet device by limiting the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 to the range of 2-4. The total residual magnetism is the product of the residual magnetic flux density of the magnet and the volume of the magnet, and the ratio reflects the relative strength of the inner magnet 10 to the overall magnetic capability of the outer magnet 20. Limiting the ratio to the specific range of 2-4 means that the inner magnet 10 has strong total residual magnetism relative to the outer magnet 20. This relatively enhanced total residual magnetism of the inner magnet 10 can effectively affect the direction of the magnetic lines, causing the magnetic lines to form a concentrated and relatively strong arc-shaped magnetic field on the surface of the target material 40, while effectively suppressing the divergence of the magnetic lines to the edge region of the target material 40, thereby reducing the edge leakage. By reducing the edge leakage, the magnetic flux utilization rate can be improved, the sputtering rate of the main sputtering area can be increased, and the utilization rate of the target material 40 can be improved. At the same time, the reduced edge leakage also reduces the dispersion of sputtering particles to other parts of the vacuum chamber, thereby reducing chamber contamination and reducing equipment maintenance frequency and use cost. Therefore, limiting the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 to the specific range of 2-4 is a further improvement for the edge leakage problem in the prior art, which can bring excellent magnetic field control effect, thereby effectively solving the problems of low utilization rate of the target material 40 and increased chamber contamination. One preferred way: the total height and residual magnetic flux density of the inner magnet 10 and the outer magnet 20 are the same, the ratio of the total width of the inner magnet 10 to the total width of the outer magnet 20 is equal to 2, and the target surface magnetic induction intensity distribution of the magnet device applied in the planar cathode is as shown in the following figure: Figure 2 As shown in the figure, the abscissa represents the distance x (unit: mm) of the target material of the planar cathode (the surface of the target material is a plane), and the ordinate represents the target surface magnetic induction intensity B / / (unit: G). Before the improvement, the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 is 1:1.

[0039] In some embodiments, the inner magnet 10 and the outer magnet 20 are cuboids.

[0040] Specifically, the shape of the inner magnet 10 and the outer magnet 20 is limited to a cuboid because the cuboid-shaped magnet has the advantages of simple manufacturing and easy processing. In a magnetron sputtering cathode that reduces edge leakage, the cuboid-shaped magnet is easy to arrange and combine, and a linear or rectangular magnetic field track suitable for a planar target can be conveniently constructed, which helps to form a uniform sputtering area. It is precisely because of this specific shape that the magnetic field distribution of the magnet in the edge region is relatively easy to control. On this basis, in combination with the limitation that the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 is greater than or equal to 1.3, by adjusting the specific size of the cuboid magnet and in combination with the residual magnetic flux density, the magnetic field distribution can be more accurately regulated and controlled, and the edge leakage can be effectively suppressed.

[0041] In some embodiments, the total height and the residual flux density of the inner magnet 10 and the outer magnet 20 are the same, and the ratio of the total width of the inner magnet 10 to the total width of the outer magnet 20 is greater than or equal to 1.3.

[0042] Specifically, in the magnet device employing cuboid-shaped inner magnet 10 and outer magnet 20, the total height of the inner magnet 10 and the outer magnet 20 is the same, and the residual flux density is the same. This setting makes the magnetic performance and size of the magnet in the vertical direction consistent, providing a basis for adjusting the magnetic field distribution in the horizontal direction. On this basis, by setting the total width of the inner magnet 10 to be more than 1.3 times or more of the total width of the outer magnet 20, the inner magnet 10 has a relatively larger size in the horizontal direction. Combined with the condition that the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 is greater than or equal to 1.3, the magnetic field generated by the inner magnet 10 has a more prominent effect on the overall magnetic field distribution. This relatively wide inner magnet 10 layout can more effectively guide and constrain the magnetic force lines to form a more concentrated and ideal magnetic field distribution on the surface of the target material 40. The magnetic force lines are more restricted above the effective sputtering area of the target material 40, reducing the diffusion of the magnetic field to the edge area of the target material 40. In this way, the edge leakage phenomenon can be suppressed, making the magnetic field distribution on the surface of the target material 40 more uniform, improving the effective utilization area of the target material 40, and at the same time, the dispersion of sputtering particles to other parts of the chamber is reduced, reducing chamber contamination. One preferred way: the total height and the residual flux density of the inner magnet 10 and the outer magnet 20 are the same, and the ratio of the total width of the inner magnet 10 to the total width of the outer magnet 20 is equal to 2, the target surface magnetic induction intensity distribution (i.e. after improvement) of the magnet device applied in the rotary cathode before and after improvement is as shown in Figure 3 The horizontal axis represents the angle (unit: °) of the target material (the surface of the target material is circular) of the rotary cathode, and the vertical axis represents the target surface magnetic induction intensity B / / (unit: G).

[0043] Similarly, the total width and the residual flux density of the inner magnet 10 and the outer magnet 20 are the same, and the ratio of the total height of the inner magnet 10 to the total height of the outer magnet 20 is greater than or equal to 1.3, and the effect is similar, which is not described in detail here.

[0044] In some embodiments, the total volume of the inner magnet 10 and the outer magnet 20 is the same, and the ratio of the residual flux density of the inner magnet 10 to the residual flux density of the outer magnet 20 is greater than or equal to 1.3.

[0045] Specifically, the application achieves that the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 is greater than or equal to 1.3 by limiting the total volume of the inner magnet 10 and the outer magnet 20 to be the same and limiting the ratio of the residual magnetic flux density of the inner magnet 10 to the residual magnetic flux density of the outer magnet 20 to be greater than or equal to 1.3. The reason for adopting the design of the same total volume of the inner magnet 10 and the outer magnet 20 is that, under the premise of the volume relationship being determined, the ratio of the total residual magnetism can be directly controlled by adjusting the residual magnetic flux density of the magnet material, thereby simplifying the design and selection process of the magnet. The distribution of the magnetic field on the surface of the target material 40 can be further improved, the edge magnetic leakage can be effectively reduced, the reduction of the edge magnetic leakage directly leads to the improvement of the magnetic flux utilization rate, the sputtering rate of the main sputtering area of the target material 40 is improved, thereby realizing the improvement of the utilization rate of the target material 40. At the same time, the reduction of the spatial dispersion degree of the sputtering particles makes the target material 40 particles not easy to sputter onto other components of the vacuum chamber, thereby realizing the reduction of the pollution of the vacuum chamber. One preferred mode: the total volume of the inner magnet 10 and the outer magnet 20 is the same, the ratio of the residual magnetic flux density of the inner magnet 10 to the residual magnetic flux density of the outer magnet 20 is equal to 1.6, and the target surface magnetic induction intensity distribution of the magnet device applied in the planar cathode is as shown in Figure 4

[0046] In some embodiments, the total height of the inner magnet 10 and the outer magnet 20 is the same, the ratio of the total width of the inner magnet 10 to the total width of the outer magnet 20 is equal to 1.5, the ratio of the residual magnetic flux density of the inner magnet 10 to the residual magnetic flux density of the outer magnet 20 is equal to 1.2, and the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 is equal to 1.8.

[0047] Specifically, the present application further improves the magnetic field distribution of the magnet device by limiting the specific ratio of the specific size and magnetic performance parameters of the inner magnet 10 and the outer magnet 20 on the basis of the inner magnet 10 and the outer magnet 20 being in the shape of a cuboid. The total height of the inner magnet 10 and the outer magnet 20 is the same, which provides a structural basis for subsequent optimization of the size and magnetic performance parameters. The ratio of the total width of the inner magnet 10 to the total width of the outer magnet 20 is equal to 1.5, so that the size of the inner magnet 10 in the width direction is relatively large, which helps to enhance the magnetic field influence of the inner magnet 10 area. The ratio of the residual magnetic flux density of the inner magnet 10 to the residual magnetic flux density of the outer magnet 20 is equal to 1.2, which indicates that the magnetic flux per unit volume of the inner magnet 10 is relatively high, further enhancing the magnetic performance of the inner magnet 10. The ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 is equal to 1.8, which can further improve the distribution of the magnetic field on the surface of the target material 40 and effectively reduce the edge magnetic leakage, as shown in Figure 5 Figure 5 ​​The effect of the magnet arrangement applied in the rotary cathode, which can also be applied in the planar cathode with similar effect, is shown in the figure. Thus, the effective utilization of the target 40 can be improved, and the contamination of the vacuum chamber by the sputtered particles can be reduced.

[0048] In some embodiments, the total width of the inner magnet 10 and the outer magnet 20 is the same, the ratio of the total height of the inner magnet 10 to the total height of the outer magnet 20 is equal to 1.2, the ratio of the residual magnetic flux density of the inner magnet 10 to the residual magnetic flux density of the outer magnet 20 is equal to 1.3, and the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 is equal to 1.56.

[0049] Specifically, by limiting the specific size ratio and material property ratio of the inner magnet 10 and the outer magnet 20, i.e., the total width of the inner magnet 10 and the outer magnet 20 is the same, the ratio of the total height of the inner magnet 10 to the total height of the outer magnet 20 is equal to 1.2, and the ratio of the residual magnetic flux density of the inner magnet 10 to the residual magnetic flux density of the outer magnet 20 is equal to 1.3, so that the ratio of the total residual magnetism of the inner magnet 10 to the total residual magnetism of the outer magnet 20 is exactly equal to 1.56. Due to this specific combination of size and material parameters, the magnetic field distribution generated by the magnet arrangement is improved, in particular, the magnetic field intensity in the edge region of the target 40 is effectively suppressed, the drift and collision of electrons in these regions are reduced, and thus the edge leakage phenomenon is significantly reduced, as shown in the figure. Figure 6 Figure 6 The effect of the magnet arrangement applied in the rotary cathode, which can also be applied in the planar cathode with similar effect, is shown in the figure. Thus, the effective utilization of the target 40 can be improved, and the contamination of the vacuum chamber by the sputtered particles can be reduced.

[0050] In a second aspect, the present application provides a magnetron sputtering cathode with reduced edge leakage, comprising the magnet arrangement of any one of the preceding.

[0051] The magnet arrangement refers to a component for generating and shaping a magnetic field in a magnetron sputtering cathode with reduced edge leakage, which is usually composed of one or more permanent magnets arranged in a specific configuration to form a desired magnetic field distribution on the surface of the target 40, which is used to confine the plasma and guide the charged particles to bombard the surface of the target 40, thereby realizing the sputtering process.

[0052] ​Specifically, by employing such a magnet arrangement, the magnetic field distribution on the surface of the target 40 of the magnetron sputtering cathode with reduced edge magnetic leakage is improved, the magnetic field strength and gradient in the edge region are controlled, so that the plasma is more effectively confined above the main sputtering region, reducing the diffusion of the plasma to the edge region. This leads to an increase in magnetic flux utilization, an increase in plasma density and electron concentration in the main sputtering region, thereby increasing the sputtering rate of the target 40 in this region. The increase in sputtering rate enables more target 40 particles to move effectively towards the substrate direction, increasing the effective sputtering amount of the target 40 onto the substrate, thereby improving the overall utilization of the target 40. At the same time, due to the reduction of edge magnetic leakage, the intensity of the plasma in the edge region is reduced, and the possibility of target 40 particles sputtering towards other components in the vacuum chamber is also reduced, thereby reducing the contamination of the vacuum chamber. The reduced chamber contamination helps to reduce the maintenance frequency and use cost of the equipment. Therefore, by applying such a specifically designed magnet arrangement to the magnetron sputtering cathode with reduced edge magnetic leakage, the present application effectively solves the problem of reduced target 40 utilization and increased contamination of the vacuum chamber caused by edge magnetic leakage in the existing magnetron sputtering cathode with reduced edge magnetic leakage.

[0053] In some embodiments, the magnetron sputtering cathode with reduced edge magnetic leakage is a planar cathode.

[0054] Specifically, the magnet arrangement of the magnetron sputtering cathode with reduced edge magnetic leakage according to the present application is applied to a planar cathode structure, and the optimized magnet arrangement inside generates a specific magnetic field distribution on the surface of the planar target 40. This magnetic field distribution forms closed magnetic lines of force on the surface of the target 40, confining the movement of electrons in the plasma near the surface of the target 40, thereby increasing the electron density and enhancing the sputtering efficiency. Due to the design optimization of the magnet arrangement, the edge magnetic leakage is reduced, and the degree of outward diffusion of the magnetic lines of force in the edge region of the target 40 is reduced. This results in a more concentrated plasma and sputtering region within the effective area of the target 40, reducing the diffusion of sputtering particles to areas outside the edge of the target 40. Therefore, by applying the optimized magnet arrangement to the planar cathode structure, the sputtering region of the planar target 40 can be more concentrated, the effective utilization of the target 40 is improved, and the diffusion of sputtering particles to other components in the vacuum chamber is reduced, thereby reducing chamber contamination. In this way, the combination of the optimized magnet arrangement and the planar cathode structure enables the planar sputtering process to more effectively utilize the target 40 and maintain the cleanliness of the vacuum environment. In one embodiment, the planar cathode includes a target 40, a magnetic yoke 30, an inner magnet 10 and two outer magnets 20, the inner magnet 10 is arranged between the two outer magnets 20, as shown in Figure 7

[0055] In some embodiments, the magnetron sputtering cathode with reduced edge magnetic leakage is a rotary cathode.

[0056] ​The rotary cathode is provided with a specific magnet device having a ratio of total residual magnetism of the inner magnet 10 to total residual magnetism of the outer magnet 20 greater than or equal to 1.3. For example, the rotary cathode can include a target material 40, a magnetic yoke 30, two inner magnets 10, and two outer magnets 20. The two inner magnets 10 are arranged side by side in the middle of the two outer magnets 20, as shown in Figure 8

[0057] In this document, relational terms such as first and second and the like can be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions.

[0058] The above description is merely illustrative of the application and is not intended to limit the scope of the application. Various modifications and changes can be made by those of ordinary skill in the art without departing from the spirit and scope of the application. Any modification, equivalent replacement, improvement, and the like made within the spirit and principle of the application shall fall within the scope of the application.​

Claims

1. A magnet device, comprising an inner magnet (10), an outer magnet (20) and a yoke (30), wherein the inner magnet (10) and the outer magnet (20) are arranged above the yoke (30), the inner magnet (10) is arranged on the inner side of the outer magnet (20), and the polarities of the inner magnet (10) and the outer magnet (20) facing upward are opposite, characterized in that: The ratio of the total remanence of the inner magnet (10) to the total remanence of the outer magnet (20) is greater than or equal to 1.3, and the total remanence refers to the product of the residual magnetic flux density of the magnet and the volume of the magnet.

2. The magnet device according to claim 1, wherein The ratio of the total remanence of the inner magnet (10) to the total remanence of the outer magnet (20) is in the range of 2-4.

3. The magnet device according to claim 1, wherein The inner magnet (10) and the outer magnet (20) are in the shape of a cuboid.

4. The magnet device according to claim 3, characterized in that The total height and residual magnetic flux density of the inner magnet (10) and the outer magnet (20) are the same, and the ratio of the total width of the inner magnet (10) to the total width of the outer magnet (20) is greater than or equal to 1.

3.

5. The magnet device according to claim 3, characterized in that The total volume of the inner magnet (10) and the outer magnet (20) is the same, and the ratio of the residual magnetic flux density of the inner magnet (10) to the residual magnetic flux density of the outer magnet (20) is greater than or equal to 1.

3.

6. The magnet device according to claim 3, characterized in that The total height of the inner magnet (10) and the outer magnet (20) is the same, the ratio of the total width of the inner magnet (10) to the total width of the outer magnet (20) is equal to 1.5, the ratio of the residual magnetic flux density of the inner magnet (10) to the residual magnetic flux density of the outer magnet (20) is equal to 1.2, and the ratio of the total residual magnetism of the inner magnet (10) to the total residual magnetism of the outer magnet (20) is equal to 1.

8.

7. The magnet device according to claim 3, characterized in that The total width of the inner magnet (10) and the outer magnet (20) is the same, the ratio of the total height of the inner magnet (10) to the total height of the outer magnet (20) is equal to 1.2, the ratio of the residual magnetic flux density of the inner magnet (10) to the residual magnetic flux density of the outer magnet (20) is equal to 1.3, and the ratio of the total residual magnetism of the inner magnet (10) to the total residual magnetism of the outer magnet (20) is equal to 1.

56.

8. A magnetron sputtering cathode for reducing edge magnetic flux leakage, characterized in that: The invention comprises the magnet device according to any one of claims 1 to 7.

9. The magnetron sputtering cathode for reducing edge magnetic flux leakage according to claim 8, characterized in that: The magnetron sputtering cathode for reducing edge magnetic leakage is a planar cathode.

10. The magnetron sputtering cathode with reduced edge magnetic flux leakage according to claim 8, characterized in that: The magnetron sputtering cathode for reducing edge magnetic leakage is a rotating cathode.

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