Rectangular magnetron sputtering cathode magnetic field optimization design method

Abstract

The invention discloses a rectangular magnetron sputtering cathode magnetic field optimization design method, and particularly relates to the technical field of magnetron sputtering, and a magnetron sputtering cathode comprises a magnet yoke, an inner magnetic pole, an outer magnetic pole, a pole shoe, a target seat, a back plate, a target material and a protective cover. The outer magnetic pole and the inner magnetic pole are set to form a runway shape, the two ends are arranged in an arc shape and can serve as an effective sputtering area, the utilization rate of the target material is increased, the heights of the inner magnet and the outer magnet are tested and determined to be 20 mm optimally, the heights of the inner magnet and the outer magnet are set to be 20 mm, and the distribution uniformity of the parallel magnetic field intensity on the surface of the target material is not affected; the maximum parallel magnetic field intensity increase amplitude is 11.3%, the magnetic field intensity is optimal, the uniformity is not affected, the denudation uniformity of the target material is effectively improved, the protection cover and the electromagnetic shielding cover are arranged to protect the inner magnetic pole and the outer magnetic pole, the magnetic field intensity is ensured, meanwhile, non-target material sputtering is avoided, and the influence on the coating purity is reduced to a certain extent.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetron sputtering, and more specifically, to a method for optimizing the design of a rectangular magnetron sputtering cathode magnetic field. Background Art

[0002] Magnetron sputtering coating equipment uses sputtering method to achieve fast and low-temperature thin film growth. Compared with thermal evaporation and arc plating, magnetron sputtering thin film deposition process is stable, easy to control, strong target material design, and easy to obtain large-area uniform thin films; at the same time, the ion energy of magnetron sputtering film formation is higher than thermal evaporation and lower than arc plating, so it is easy to obtain thin films with strong adhesion, high density and low internal stress.

[0003] The working principle of magnetron sputtering is that electrons collide with argon atoms in the process of flying to the substrate under the action of the electric field E, ionizing them to produce Ar positive ions and new electrons; the new electrons fly to the substrate, and the Ar ions are accelerated to fly to the cathode target under the action of the electric field, and bombard the target surface with high energy, causing the target material to sputter. Among the sputtered particles, neutral target atoms or molecules are deposited on the substrate to form a thin film, and the secondary electrons generated will be affected by the electric field and magnetic field, resulting in a drift in the direction indicated by E (electric field) × B (magnetic field), referred to as E × B drift, and its motion trajectory is similar to a cycloid. If it is a circular magnetic field, the electrons will move in a circular motion on the target surface in an approximate cycloid form. Their motion path is not only very long, but also bound in the plasma region close to the target surface, and a large amount of Ar is ionized in this region to bombard the target material, thereby achieving a high deposition rate. As the number of collisions increases, the energy of the secondary electrons is exhausted, gradually moving away from the target surface, and finally deposited on the substrate under the action of the electric field E. Since the energy of the electron is very low, the energy transferred to the substrate is very small, resulting in a low temperature rise of the substrate.

[0004] Magnetron sputtering is a collision process between incident particles and targets. The incident particles undergo a complex scattering process in the target, collide with target atoms, and transfer part of their momentum to target atoms, which in turn collide with other target atoms, forming a cascade process. In this cascade process, some target atoms near the surface gain enough momentum to move outward, leaving the target and being sputtered out.

[0005] The cathode magnetic field design in the magnetron sputtering process has a high correlation with the cost-effectiveness of the coating and the characteristics of the film. Therefore, the optimal design of the cathode magnetic field is of great significance. After the cathode magnetic field is optimized, the utilization rate of the target material can be improved and the production and processing costs can be reduced. Summary of the invention

[0006] In order to overcome the above-mentioned defects, the present invention provides a method for optimizing the design of a rectangular magnetron sputtering cathode magnetic field. The cathode magnetic field design in the magnetron sputtering process has a high correlation with the cost-effectiveness of the coating and the characteristics of the film, so the optimization design of the cathode magnetic field is of great significance.

[0007] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a method for optimizing the magnetic field design of a rectangular magnetron sputtering cathode, wherein the magnetron sputtering cathode comprises a magnetic yoke, an inner magnetic pole, an outer magnetic pole, a pole shoe, a target seat, a back plate, a target material and a protective cover, wherein the two sides of the magnetic yoke are connected to the bottoms of the two outer magnetic poles, the inner magnetic pole is located between the two outer magnetic poles, the bottom of the inner magnetic pole is connected to the middle of the magnetic yoke, the inner magnetic pole and the two outer magnetic poles are connected to the pole shoe, and several pole shoes are connected to the target seat, the back plate and the target material are installed on the target seat, and a magnetic conductive sheet is provided under the target seat, and the optimization design method comprises the following steps:

[0008] S1. First, simulate and analyze the magnetic field distribution on the surface of the rectangular sputtering target;

[0009] S2, the two ends of the outer magnetic pole are adjusted to a racetrack shape;

[0010] S3, simulating the magnetic field intensity distribution of inner magnetic poles and outer magnetic poles of different sizes;

[0011] S4, finally determining and adjusting the heights of the inner magnetic pole and the outer magnetic pole;

[0012] S5. Simulate the distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets to determine the optimal layout of the magnetic conductive sheets and the design parameters of the magnetron sputtering target;

[0013] S6. Determine the optimal distance between the two magnetic conductive sheets and adjust it to optimize the cathode magnetic field of the magnetron sputtering.

[0014] As a further solution of the present invention: the simulation analysis of the magnetic field distribution on the surface of a rectangular sputtering target is, specifically, the target length excluding the range of one target width at each end is defined as a straight runway area, and the other positions at the two ends are ends. The magnetic field distribution along the x direction in the straight runway area, the uniformity of the horizontal magnetic field along the y direction, and the magnetic field distribution in the end area. For the straight runway area, when it is far away from the end, the magnetic field has only x and z components, the z component refers to the component of the magnetic field in the vertical direction, and the y component is almost zero. When it is close to the end, the y component value increases, and changes rapidly with the y direction position. At this time, the y component of the magnetic field has a very significant impact on the horizontal component. Measurement shows that the x component magnetic field intensity at the end position is weaker than that in the straight runway area, and the sputtering etching efficiency of the target is low.

[0015] As a further solution of the present invention: the simulation of the magnetic field strength distribution of inner and outer magnetic poles of different sizes is specifically to select five heights of inner and outer magnetic poles, and the five heights of the inner and outer magnetic poles are 15mm, 20mm, 25mm, 30mm, and 35mm, respectively. As the heights of the inner and outer magnetic poles increase, the parallel magnetic field strength on the target surface also increases, but the increase gradually decreases, and has no effect on the uniformity of the parallel magnetic field strength distribution on the target surface. For every 5mm increase in the magnet height, the increase in the maximum parallel magnetic field strength is 8.5%, 11.3%, 7.2%, 3.3%, and 1.6%, respectively. The heights of the inner and outer magnetic poles can be preliminarily selected based on this, and the optimal height of the inner and outer magnetic poles is 20mm.

[0016] As a further solution of the present invention: the simulation of the distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets is as follows: first, the spacing between the magnetic conductive sheet and the inner magnetic pole, and the spacing between the magnetic conductive sheet and the outer magnetic pole is set to 2mm, and the distance between the two magnetic conductive sheets on the same side is 1mm, 0.6mm, and 0.2mm. In the process of changing the spacing between the two magnetic conductive sheets from 1mm to 0.2mm, the magnetic induction intensity on the target surface changes significantly in the middle area, which plays a major role in regulating the uniformity of the horizontal magnetic induction intensity on the target surface in this area. As the spacing between the two magnetic conductive sheets continues to decrease, the peak value of the horizontal magnetic induction intensity on the target surface continues to decrease. The spacing between the two magnetic conductive sheets is 0.2mm.

[0017] As a further solution of the present invention: the protective cover is an electromagnetic shielding cover, and the thickness of the target material is 6 mm.

[0018] The beneficial effects of the present invention are:

[0019] The present invention sets the outer magnetic pole and the inner magnetic pole to form a racetrack shape, and the arc-shaped setting at both ends can be used as an effective sputtering area, thereby increasing the utilization rate of the target material. The heights of the inner magnet and the outer magnet are experimented and determined to be 20 mm as the best. The heights of the inner magnet and the outer magnet are set to 20 mm, which does not affect the uniformity of the parallel magnetic field intensity distribution on the target surface, and the maximum parallel magnetic field intensity increases by 11.3%. The magnetic field intensity is optimal and the uniformity is not affected, which effectively improves the erosion uniformity of the target material. A protective cover is provided, and an electromagnetic shielding cover protects the inner magnetic pole and the outer magnetic pole to ensure the magnetic field strength, while avoiding the sputtering of non-target materials, thereby reducing the influence on the purity of the coating to a certain extent. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the sputtering cathode of the present invention;

[0021] Figure 2 It is a schematic diagram of magnetic poles of the present invention;

[0022] Figure 3It is a schematic diagram of a rectangular magnetron target magnet of the present invention. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Embodiment 1:

[0025] A rectangular magnetron sputtering cathode magnetic field optimization design method, the magnetron sputtering cathode comprises a magnetic yoke, an inner magnetic pole, an outer magnetic pole, a pole shoe, a target seat, a back plate, a target material and a protective cover, the two sides of the magnetic yoke are connected to the bottom of the two outer magnetic poles, the inner magnetic pole is located between the two outer magnetic poles, the bottom of the inner magnetic pole is connected to the middle of the magnetic yoke, the inner magnetic pole and the two outer magnetic poles are connected to the pole shoe, a plurality of pole shoes are connected to the target seat, the back plate and the target material are installed on the target seat, and a magnetic conductive sheet is provided under the target seat. The optimization design method comprises the following steps:

[0026] S1. First, simulate and analyze the magnetic field distribution on the surface of the rectangular sputtering target;

[0027] First, a physical model of a rectangular sputtering target is established, and ANSYS and Comsol Multiphys simulation software are selected to simulate the magnetic field distribution. The physical field is defined in the simulation software, the model is meshed, and the magnetic field distribution is calculated by running the simulation software.

[0028] S2, the two ends of the outer magnetic pole are adjusted to a racetrack shape;

[0029] The two ends of the outer magnetic poles are adjusted to a racetrack design to improve the uniformity and controllability of the magnetic field. The racetrack design helps to reduce the edge effect, making the magnetic field more concentrated and uniform in the working area;

[0030] S3, simulating the magnetic field intensity distribution of inner magnetic poles and outer magnetic poles of different sizes;

[0031] First, define the geometric shape and size of the magnetic poles. According to the properties of the magnetic pole materials, set their magnetic permeability and magnetization properties. Set boundary conditions in the simulation software, mesh the simulation area for numerical calculations, and use electromagnetic field simulation software to solve the magnetic field distribution according to the electromagnetic field theory of Maxwell's equations. After the simulation is completed, analyze the strength, direction and distribution characteristics of the magnetic field.

[0032] S4, finally determine and adjust the heights of the inner magnetic pole and the outer magnetic pole, measure the parallel magnetic field strength on the target surface according to the different heights of the inner magnetic pole and the outer magnetic pole, and judge the uniformity of the parallel magnetic field strength distribution on the target surface;

[0033] S5. Simulate the distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets to determine the optimal layout of the magnetic conductive sheets and the design parameters of the magnetron sputtering target;

[0034] S6, determining the optimal distance between the two magnetic guide sheets and adjusting it to optimize the cathode magnetic field of the magnetron sputtering;

[0035] Finite element analysis is performed using computer-aided engineering software to simulate and predict the magnetic field distribution under different magnetic conductive sheet layouts. Experimental adjustments are made on the actual magnetron sputtering equipment to gradually change the distance between the magnetic conductive sheets. Magnetic field detection tools are used to monitor the magnetic field changes and evaluate the film deposition quality under different magnetic field configurations, including the thickness uniformity, composition consistency and microstructure of the film. Based on the experimental results and performance evaluation, the position of the magnetic conductive sheets is repeatedly adjusted until the optimal distance is found to achieve the optimal magnetic field uniformity and film quality.

[0036] The magnetic field distribution on the surface of a rectangular sputtering target is simulated and analyzed. Specifically, the target length minus one target width at each end is defined as the straight runway area, and the other positions at the two ends are the ends. The magnetic field distribution along the x direction in the straight runway area, the uniformity of the horizontal magnetic field along the y direction, and the magnetic field distribution in the end area are analyzed. For the straight runway area, when it is far away from the end, the magnetic field has only x and z components, the z component refers to the component of the magnetic field in the vertical direction, and the y component is almost zero. When it is close to the end, the y component value increases, and changes rapidly with the y direction position. At this time, the y component of the magnetic field has a significant impact on the horizontal component. Measurements show that the x-component magnetic field intensity at the end position is weaker than that in the straight runway area, and the sputtering etching efficiency of the target is low.

[0037] Due to the uneven etching of the target end, the film deposition in the target end area is uneven, which cannot be used as an effective sputtering area. At the same time, the target utilization rate is reduced. The magnet of the rectangular planar magnetron sputtering target is designed into a runway-shaped structure, that is, the outer magnetic steel end of the rectangular target is designed into an arc shape.

[0038] The magnetic field strength distribution of inner and outer magnetic poles of different sizes is simulated. Specifically, the height of the inner and outer magnetic poles is selected to be 15 mm, and the increase in the maximum parallel magnetic field strength is 8.5%. By conducting experiments on the heights of the inner and outer magnets, the uniformity of the parallel magnetic field strength distribution on the target surface is analyzed.

[0039] The distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets was simulated. Specifically, the spacing between the magnetic conductive sheet and the inner magnetic pole, and between the magnetic conductive sheet and the outer magnetic pole was first set to 2mm, and the distance between the two magnetic conductive sheets on the same side was 1mm, 0.6mm, and 0.2mm. In the process of the spacing between the two magnetic conductive sheets changing from 1mm to 0.2mm, the magnetic induction intensity on the target surface showed obvious changes in the middle area, which played a major role in regulating the uniformity of the horizontal magnetic induction intensity on the target surface in this area. As the spacing between the two magnetic conductive sheets continued to decrease, the peak value of the horizontal magnetic induction intensity on the target surface dropped to the lowest. Under the premise that the maximum parallel magnetic field intensity increased by 8.5%, the spacing between the two magnetic conductive sheets was 0.2mm.

[0040] The protective cover is an electromagnetic shielding cover, and the thickness of the target material is 6 mm. By setting the protective cover, the electromagnetic shielding cover protects the inner magnetic pole and the outer magnetic pole to ensure the magnetic field strength, while avoiding the sputtering of non-target materials, reducing the impact on the purity of the coating to a certain extent.

[0041] Embodiment 2:

[0042] A rectangular magnetron sputtering cathode magnetic field optimization design method, the magnetron sputtering cathode comprises a magnetic yoke, an inner magnetic pole, an outer magnetic pole, a pole shoe, a target seat, a back plate, a target material and a protective cover, the two sides of the magnetic yoke are connected to the bottoms of the two outer magnetic poles, the inner magnetic pole is located between the two outer magnetic poles, the bottom of the inner magnetic pole is connected to the middle of the magnetic yoke, the inner magnetic pole and the two outer magnetic poles are connected to the pole shoe, a plurality of pole shoes are connected to the target seat, the back plate and the target material are installed on the target seat, and a magnetic conductive sheet is provided under the target seat. The optimization design method comprises the following steps:

[0043] S1. First, simulate and analyze the magnetic field distribution on the surface of the rectangular sputtering target;

[0044] First, a physical model of a rectangular sputtering target is established, and ANSYS and Comsol Multiphys simulation software are selected to simulate the magnetic field distribution. The physical field is defined in the simulation software, the model is meshed, and the magnetic field distribution is calculated by running the simulation software.

[0045] S2, the two ends of the outer magnetic pole are adjusted to a racetrack shape;

[0046] The two ends of the outer magnetic poles are adjusted to a racetrack design to improve the uniformity and controllability of the magnetic field. The racetrack design helps to reduce the edge effect, making the magnetic field more concentrated and uniform in the working area;

[0047] S3, simulating the magnetic field intensity distribution of inner magnetic poles and outer magnetic poles of different sizes;

[0048] First, define the geometric shape and size of the magnetic poles. According to the properties of the magnetic pole materials, set their magnetic permeability and magnetization properties. Set boundary conditions in the simulation software, mesh the simulation area for numerical calculations, and use electromagnetic field simulation software to solve the magnetic field distribution according to the electromagnetic field theory of Maxwell's equations. After the simulation is completed, analyze the strength, direction and distribution characteristics of the magnetic field.

[0049] S4, finally determine and adjust the heights of the inner magnetic pole and the outer magnetic pole, measure the parallel magnetic field strength on the target surface according to the different heights of the inner magnetic pole and the outer magnetic pole, and judge the uniformity of the parallel magnetic field strength distribution on the target surface;

[0050] S5. Simulate the distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets to determine the optimal layout of the magnetic conductive sheets and the design parameters of the magnetron sputtering target;

[0051] S6, determining the optimal distance between the two magnetic guide sheets and adjusting it to optimize the cathode magnetic field of the magnetron sputtering;

[0052] Finite element analysis is performed using computer-aided engineering software to simulate and predict the magnetic field distribution under different magnetic conductive sheet layouts. Experimental adjustments are made on the actual magnetron sputtering equipment to gradually change the distance between the magnetic conductive sheets. Magnetic field detection tools are used to monitor the magnetic field changes and evaluate the film deposition quality under different magnetic field configurations, including the thickness uniformity, composition consistency and microstructure of the film. Based on the experimental results and performance evaluation, the position of the magnetic conductive sheets is repeatedly adjusted until the optimal distance is found to achieve the optimal magnetic field uniformity and film quality.

[0053] The magnetic field distribution on the surface of a rectangular sputtering target is simulated and analyzed. Specifically, the target length minus one target width at each end is defined as the straight runway area, and the other positions at the two ends are the ends. The magnetic field distribution along the x direction in the straight runway area, the uniformity of the horizontal magnetic field along the y direction, and the magnetic field distribution in the end area are analyzed. For the straight runway area, when it is far away from the end, the magnetic field has only x and z components, the z component refers to the component of the magnetic field in the vertical direction, and the y component is almost zero. When it is close to the end, the y component value increases, and changes rapidly with the y direction position. At this time, the y component of the magnetic field has a significant impact on the horizontal component. Measurements show that the x-component magnetic field intensity at the end position is weaker than that in the straight runway area, and the sputtering etching efficiency of the target is low.

[0054] Due to the uneven etching of the target end, the film deposition in the target end area is uneven, which cannot be used as an effective sputtering area. At the same time, the target utilization rate is reduced. The magnet of the rectangular planar magnetron sputtering target is designed into a runway-shaped structure, that is, the outer magnetic steel end of the rectangular target is designed into an arc shape.

[0055] The magnetic field strength distribution of inner and outer magnetic poles of different sizes is simulated. Specifically, two heights of the inner and outer magnetic poles are selected, each of which is 20 mm. As the heights of the inner and outer magnetic poles increase, the parallel magnetic field strength on the target surface also increases. For every 5 mm increase in the magnet height, the maximum parallel magnetic field strength increases by 11.3%. By conducting experiments on the heights of the inner and outer magnets, the uniformity of the parallel magnetic field strength distribution on the target surface is analyzed.

[0056] The distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets was simulated. Specifically, the spacing between the magnetic conductive sheet and the inner magnetic pole, and between the magnetic conductive sheet and the outer magnetic pole was first set to 2mm, and the distance between the two magnetic conductive sheets on the same side was 1mm, 0.6mm, and 0.2mm. In the process of the spacing between the two magnetic conductive sheets changing from 1mm to 0.2mm, the magnetic induction intensity on the target surface showed obvious changes in the middle area, which played a major role in regulating the uniformity of the horizontal magnetic induction intensity on the target surface in this area. As the spacing between the two magnetic conductive sheets continued to decrease, the peak value of the horizontal magnetic induction intensity on the target surface dropped to the lowest. Under the premise that the maximum parallel magnetic field intensity increased by 11.3%, the spacing between the two magnetic conductive sheets was 0.2mm.

[0057] The protective cover is an electromagnetic shielding cover, and the thickness of the target material is 6 mm. By setting the protective cover, the electromagnetic shielding cover protects the inner magnetic pole and the outer magnetic pole to ensure the magnetic field strength, while avoiding the sputtering of non-target materials, reducing the impact on the purity of the coating to a certain extent.

[0058] Embodiment 3:

[0059] A rectangular magnetron sputtering cathode magnetic field optimization design method, the magnetron sputtering cathode comprises a magnetic yoke, an inner magnetic pole, an outer magnetic pole, a pole shoe, a target seat, a back plate, a target material and a protective cover, the two sides of the magnetic yoke are connected to the bottoms of the two outer magnetic poles, the inner magnetic pole is located between the two outer magnetic poles, the bottom of the inner magnetic pole is connected to the middle of the magnetic yoke, the inner magnetic pole and the two outer magnetic poles are connected to the pole shoe, a plurality of pole shoes are connected to the target seat, the back plate and the target material are installed on the target seat, and a magnetic conductive sheet is provided under the target seat. The optimization design method comprises the following steps:

[0060] S1. First, simulate and analyze the magnetic field distribution on the surface of the rectangular sputtering target;

[0061] First, a physical model of a rectangular sputtering target is established, and ANSYS and Comsol Multiphys simulation software are selected to simulate the magnetic field distribution. The physical field is defined in the simulation software, the model is meshed, and the magnetic field distribution is calculated by running the simulation software.

[0062] S2, the two ends of the outer magnetic pole are adjusted to a racetrack shape;

[0063] The two ends of the outer magnetic poles are adjusted to a racetrack design to improve the uniformity and controllability of the magnetic field. The racetrack design helps to reduce the edge effect, making the magnetic field more concentrated and uniform in the working area;

[0064] S3, simulating the magnetic field intensity distribution of inner magnetic poles and outer magnetic poles of different sizes;

[0065] First, define the geometric shape and size of the magnetic poles. According to the properties of the magnetic pole materials, set their magnetic permeability and magnetization properties. Set boundary conditions in the simulation software, mesh the simulation area for numerical calculations, and use electromagnetic field simulation software to solve the magnetic field distribution according to the electromagnetic field theory of Maxwell's equations. After the simulation is completed, analyze the strength, direction and distribution characteristics of the magnetic field.

[0066] S4, finally determine and adjust the heights of the inner magnetic pole and the outer magnetic pole, measure the parallel magnetic field strength on the target surface according to the different heights of the inner magnetic pole and the outer magnetic pole, and judge the uniformity of the parallel magnetic field strength distribution on the target surface;

[0067] S5. Simulate the distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets to determine the optimal layout of the magnetic conductive sheets and the design parameters of the magnetron sputtering target;

[0068] S6, determining the optimal distance between the two magnetic guide sheets and adjusting it to optimize the cathode magnetic field of the magnetron sputtering;

[0069] Finite element analysis is performed using computer-aided engineering software to simulate and predict the magnetic field distribution under different magnetic conductive sheet layouts. Experimental adjustments are made on the actual magnetron sputtering equipment to gradually change the distance between the magnetic conductive sheets. Magnetic field detection tools are used to monitor the magnetic field changes and evaluate the film deposition quality under different magnetic field configurations, including the thickness uniformity, composition consistency and microstructure of the film. Based on the experimental results and performance evaluation, the position of the magnetic conductive sheets is repeatedly adjusted until the optimal distance is found to achieve the optimal magnetic field uniformity and film quality.

[0070] The magnetic field distribution on the surface of a rectangular sputtering target is simulated and analyzed. Specifically, the target length minus one target width at each end is defined as the straight runway area, and the other positions at the two ends are the ends. The magnetic field distribution along the x direction in the straight runway area, the uniformity of the horizontal magnetic field along the y direction, and the magnetic field distribution in the end area are analyzed. For the straight runway area, when it is far away from the end, the magnetic field has only x and z components, the z component refers to the component of the magnetic field in the vertical direction, and the y component is almost zero. When it is close to the end, the y component value increases, and changes rapidly with the y direction position. At this time, the y component of the magnetic field has a significant impact on the horizontal component. Measurements show that the x-component magnetic field intensity at the end position is weaker than that in the straight runway area, and the sputtering etching efficiency of the target is low.

[0071] Due to the uneven etching of the target end, the film deposition in the target end area is uneven, which cannot be used as an effective sputtering area. At the same time, the target utilization rate is reduced. The magnet of the rectangular planar magnetron sputtering target is designed into a runway-shaped structure, that is, the outer magnetic steel end of the rectangular target is designed into an arc shape.

[0072] The magnetic field strength distribution of inner and outer magnetic poles of different sizes is simulated. Specifically, two heights of the inner and outer magnetic poles are selected, each of which is 25 mm. As the heights of the inner and outer magnetic poles increase, the parallel magnetic field strength on the target surface also increases. For every 5 mm increase in the magnet height, the maximum parallel magnetic field strength increases by 7.2%. By conducting experiments on the heights of the inner and outer magnets, the uniformity of the parallel magnetic field strength distribution on the target surface is analyzed.

[0073] The distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets was simulated. Specifically, the spacing between the magnetic conductive sheet and the inner magnetic pole, and between the magnetic conductive sheet and the outer magnetic pole was first set to 2mm, and the distance between the two magnetic conductive sheets on the same side was 1mm, 0.6mm, and 0.2mm. In the process of the spacing between the two magnetic conductive sheets changing from 1mm to 0.2mm, the magnetic induction intensity on the target surface showed obvious changes in the middle area, which played a major role in regulating the uniformity of the horizontal magnetic induction intensity on the target surface in this area. As the spacing between the two magnetic conductive sheets continued to decrease, when the peak value of the horizontal magnetic induction intensity on the target surface dropped to the minimum, the spacing between the two magnetic conductive sheets was 0.2mm, provided that the increase in the maximum parallel magnetic field intensity was 7.2% respectively.

[0074] The protective cover is an electromagnetic shielding cover, and the thickness of the target material is 6 mm. By setting the protective cover, the electromagnetic shielding cover protects the inner magnetic pole and the outer magnetic pole to ensure the magnetic field strength, while avoiding the sputtering of non-target materials, reducing the impact on the purity of the coating to a certain extent.

[0075] Embodiment 4:

[0076] A rectangular magnetron sputtering cathode magnetic field optimization design method, the magnetron sputtering cathode comprises a magnetic yoke, an inner magnetic pole, an outer magnetic pole, a pole shoe, a target seat, a back plate, a target material and a protective cover, the two sides of the magnetic yoke are connected to the bottoms of the two outer magnetic poles, the inner magnetic pole is located between the two outer magnetic poles, the bottom of the inner magnetic pole is connected to the middle of the magnetic yoke, the inner magnetic pole and the two outer magnetic poles are connected to the pole shoe, a plurality of pole shoes are connected to the target seat, the back plate and the target material are installed on the target seat, and a magnetic conductive sheet is provided under the target seat. The optimization design method comprises the following steps:

[0077] S1. First, simulate and analyze the magnetic field distribution on the surface of the rectangular sputtering target;

[0078] First, a physical model of a rectangular sputtering target is established, and ANSYS and Comsol Multiphys simulation software are selected to simulate the magnetic field distribution. The physical field is defined in the simulation software, the model is meshed, and the magnetic field distribution is calculated by running the simulation software.

[0079] S2, the two ends of the outer magnetic pole are adjusted to a racetrack shape;

[0080] The two ends of the outer magnetic poles are adjusted to a racetrack design to improve the uniformity and controllability of the magnetic field. The racetrack design helps to reduce the edge effect, making the magnetic field more concentrated and uniform in the working area;

[0081] S3, simulating the magnetic field intensity distribution of inner magnetic poles and outer magnetic poles of different sizes;

[0082] First, define the geometric shape and size of the magnetic poles. According to the properties of the magnetic pole materials, set their magnetic permeability and magnetization properties. Set boundary conditions in the simulation software, mesh the simulation area for numerical calculations, and use electromagnetic field simulation software to solve the magnetic field distribution according to the electromagnetic field theory of Maxwell's equations. After the simulation is completed, analyze the strength, direction and distribution characteristics of the magnetic field.

[0083] S4, finally determine and adjust the heights of the inner magnetic pole and the outer magnetic pole, measure the parallel magnetic field strength on the target surface according to the different heights of the inner magnetic pole and the outer magnetic pole, and judge the uniformity of the parallel magnetic field strength distribution on the target surface;

[0084] S5. Simulate the distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets to determine the optimal layout of the magnetic conductive sheets and the design parameters of the magnetron sputtering target;

[0085] S6, determining the optimal distance between the two magnetic guide sheets and adjusting it to optimize the cathode magnetic field of the magnetron sputtering;

[0086] Finite element analysis is performed using computer-aided engineering software to simulate and predict the magnetic field distribution under different magnetic conductive sheet layouts. Experimental adjustments are made on the actual magnetron sputtering equipment to gradually change the distance between the magnetic conductive sheets. Magnetic field detection tools are used to monitor the magnetic field changes and evaluate the film deposition quality under different magnetic field configurations, including the thickness uniformity, composition consistency and microstructure of the film. Based on the experimental results and performance evaluation, the position of the magnetic conductive sheets is repeatedly adjusted until the optimal distance is found to achieve the optimal magnetic field uniformity and film quality.

[0087] The magnetic field distribution on the surface of a rectangular sputtering target is simulated and analyzed. Specifically, the target length minus one target width at each end is defined as the straight runway area, and the other positions at the two ends are the ends. The magnetic field distribution along the x direction in the straight runway area, the uniformity of the horizontal magnetic field along the y direction, and the magnetic field distribution in the end area are analyzed. For the straight runway area, when it is far away from the end, the magnetic field has only x and z components, the z component refers to the component of the magnetic field in the vertical direction, and the y component is almost zero. When it is close to the end, the y component value increases, and changes rapidly with the y direction position. At this time, the y component of the magnetic field has a significant impact on the horizontal component. Measurements show that the x-component magnetic field intensity at the end position is weaker than that in the straight runway area, and the sputtering etching efficiency of the target is low.

[0088] Due to the uneven etching of the target end, the film deposition in the target end area is uneven, which cannot be used as an effective sputtering area. At the same time, the target utilization rate is reduced. The magnet of the rectangular planar magnetron sputtering target is designed into a runway-shaped structure, that is, the outer magnetic steel end of the rectangular target is designed into an arc shape.

[0089] The magnetic field intensity distribution of inner and outer magnetic poles of different sizes is simulated. Specifically, two heights of the inner and outer magnetic poles are selected, each of which is 30 mm. As the heights of the inner and outer magnetic poles increase, the parallel magnetic field intensity on the target surface also increases. For every 5 mm increase in the magnet height, the increase in the maximum parallel magnetic field intensity is 3.3%. By conducting experiments on the heights of the inner and outer magnets, the uniformity of the parallel magnetic field intensity distribution on the target surface is analyzed.

[0090] The distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets was simulated. Specifically, the spacing between the magnetic conductive sheet and the inner magnetic pole, and between the magnetic conductive sheet and the outer magnetic pole was first set to 2mm, and the distance between the two magnetic conductive sheets on the same side was 1mm, 0.6mm, and 0.2mm. In the process of the spacing between the two magnetic conductive sheets changing from 1mm to 0.2mm, the magnetic induction intensity on the target surface showed obvious changes in the middle area, which played a major role in regulating the uniformity of the horizontal magnetic induction intensity on the target surface in this area. As the spacing between the two magnetic conductive sheets continued to decrease, the peak value of the horizontal magnetic induction intensity on the target surface dropped to the lowest. Under the premise that the maximum parallel magnetic field intensity increased by 3.3%, the spacing between the two magnetic conductive sheets was 0.2mm.

[0091] The protective cover is an electromagnetic shielding cover, and the thickness of the target material is 6 mm. By setting the protective cover, the electromagnetic shielding cover protects the inner magnetic pole and the outer magnetic pole to ensure the magnetic field strength, while avoiding the sputtering of non-target materials, reducing the impact on the purity of the coating to a certain extent.

[0092] Embodiment 5:

[0093] A rectangular magnetron sputtering cathode magnetic field optimization design method, the magnetron sputtering cathode comprises a magnetic yoke, an inner magnetic pole, an outer magnetic pole, a pole shoe, a target seat, a back plate, a target material and a protective cover, the two sides of the magnetic yoke are connected to the bottoms of the two outer magnetic poles, the inner magnetic pole is located between the two outer magnetic poles, the bottom of the inner magnetic pole is connected to the middle of the magnetic yoke, the inner magnetic pole and the two outer magnetic poles are connected to the pole shoe, a plurality of pole shoes are connected to the target seat, the back plate and the target material are installed on the target seat, and a magnetic conductive sheet is provided under the target seat. The optimization design method comprises the following steps:

[0094] S1. First, simulate and analyze the magnetic field distribution on the surface of the rectangular sputtering target;

[0095] First, a physical model of a rectangular sputtering target is established, and ANSYS and Comsol Multiphys simulation software are selected to simulate the magnetic field distribution. The physical field is defined in the simulation software, the model is meshed, and the magnetic field distribution is calculated by running the simulation software.

[0096] S2, the two ends of the outer magnetic pole are adjusted to a racetrack shape;

[0097] The two ends of the outer magnetic poles are adjusted to a racetrack design to improve the uniformity and controllability of the magnetic field. The racetrack design helps to reduce the edge effect, making the magnetic field more concentrated and uniform in the working area;

[0098] S3, simulating the magnetic field intensity distribution of inner magnetic poles and outer magnetic poles of different sizes;

[0099] First, define the geometric shape and size of the magnetic poles. According to the properties of the magnetic pole materials, set their magnetic permeability and magnetization properties. Set boundary conditions in the simulation software, mesh the simulation area for numerical calculations, and use electromagnetic field simulation software to solve the magnetic field distribution according to the electromagnetic field theory of Maxwell's equations. After the simulation is completed, analyze the strength, direction and distribution characteristics of the magnetic field.

[0100] S4, finally determine and adjust the heights of the inner magnetic pole and the outer magnetic pole, measure the parallel magnetic field strength on the target surface according to the different heights of the inner magnetic pole and the outer magnetic pole, and judge the uniformity of the parallel magnetic field strength distribution on the target surface;

[0101] S5. Simulate the distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets to determine the optimal layout of the magnetic conductive sheets and the design parameters of the magnetron sputtering target;

[0102] S6, determining the optimal distance between the two magnetic guide sheets and adjusting it to optimize the cathode magnetic field of the magnetron sputtering;

[0103] Finite element analysis is performed using computer-aided engineering software to simulate and predict the magnetic field distribution under different magnetic conductive sheet layouts. Experimental adjustments are made on the actual magnetron sputtering equipment to gradually change the distance between the magnetic conductive sheets. Magnetic field detection tools are used to monitor the magnetic field changes and evaluate the film deposition quality under different magnetic field configurations, including the thickness uniformity, composition consistency and microstructure of the film. Based on the experimental results and performance evaluation, the position of the magnetic conductive sheets is repeatedly adjusted until the optimal distance is found to achieve the optimal magnetic field uniformity and film quality.

[0104] The magnetic field distribution on the surface of a rectangular sputtering target is simulated and analyzed. Specifically, the target length minus one target width at each end is defined as the straight runway area, and the other positions at the two ends are the ends. The magnetic field distribution along the x direction in the straight runway area, the uniformity of the horizontal magnetic field along the y direction, and the magnetic field distribution in the end area are analyzed. For the straight runway area, when it is far away from the end, the magnetic field has only x and z components, the z component refers to the component of the magnetic field in the vertical direction, and the y component is almost zero. When it is close to the end, the y component value increases, and changes rapidly with the y direction position. At this time, the y component of the magnetic field has a significant impact on the horizontal component. Measurements show that the x-component magnetic field intensity at the end position is weaker than that in the straight runway area, and the sputtering etching efficiency of the target is low.

[0105] Due to the uneven etching of the target end, the film deposition in the target end area is uneven, which cannot be used as an effective sputtering area. At the same time, the target utilization rate is reduced. The magnet of the rectangular planar magnetron sputtering target is designed into a runway-shaped structure, that is, the outer magnetic steel end of the rectangular target is designed into an arc shape.

[0106] The magnetic field strength distribution of inner and outer magnetic poles of different sizes is simulated. Specifically, two heights of the inner and outer magnetic poles are selected, each of which is 35 mm. As the heights of the inner and outer magnetic poles increase, the parallel magnetic field strength on the target surface also increases. For every 5 mm increase in the magnet height, the increase in the maximum parallel magnetic field strength is 1.6%. By conducting experiments on the heights of the inner and outer magnets, the uniformity of the parallel magnetic field strength distribution on the target surface is analyzed.

[0107] The distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets was simulated. Specifically, the spacing between the magnetic conductive sheet and the inner magnetic pole, and between the magnetic conductive sheet and the outer magnetic pole was first set to 2mm, and the distance between the two magnetic conductive sheets on the same side was 1mm, 0.6mm, and 0.2mm. In the process of the spacing between the two magnetic conductive sheets changing from 1mm to 0.2mm, the magnetic induction intensity on the target surface showed obvious changes in the middle area, which played a major role in regulating the uniformity of the horizontal magnetic induction intensity on the target surface in this area. As the spacing between the two magnetic conductive sheets continued to decrease, when the peak value of the horizontal magnetic induction intensity on the target surface dropped to the minimum, the spacing between the two magnetic conductive sheets was 0.2mm under the premise that the maximum parallel magnetic field intensity increased by 1.6%.

[0108] The protective cover is an electromagnetic shielding cover, and the thickness of the target material is 6 mm. By setting the protective cover, the electromagnetic shielding cover protects the inner magnetic pole and the outer magnetic pole to ensure the magnetic field strength, while avoiding the sputtering of non-target materials, reducing the impact on the purity of the coating to a certain extent.

[0109] According to Examples 1-5, it is known that:

[0110] The height of the inner and outer magnets was tested and determined to be 20 mm as the best. The height of the inner and outer magnets was set to 20 mm, which did not affect the uniformity of the parallel magnetic field intensity distribution on the target surface.

[0111] The maximum parallel magnetic field strength increased by 11.3%, the magnetic field strength was optimal, and the uniformity was not affected, which effectively improved the uniformity of target material stripping;

[0112] By adjusting the distance between the two magnetic conductive sheets, the peak value of the horizontal magnetic induction intensity on the target surface is reduced to a minimum, and the optimal distance between the two magnetic conductive sheets is 0.2 mm to ensure the uniformity of the horizontal magnetic induction intensity on the target surface.

[0113] Secondly: In the drawings of the embodiments disclosed in the present invention, only the structures related to the embodiments disclosed in the present invention are involved, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other;

[0114] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for optimizing the magnetic field design of a rectangular magnetron sputtering cathode, wherein the magnetron sputtering cathode comprises a magnetic yoke, an inner magnetic pole, an outer magnetic pole, a pole shoe, a target seat, a back plate, a target material and a protective cover, wherein the two sides of the magnetic yoke are connected to the bottoms of the two outer magnetic poles, the inner magnetic pole is located between the two outer magnetic poles, the bottom of the inner magnetic pole is connected to the middle of the magnetic yoke, the inner magnetic pole and the two outer magnetic poles are connected to the pole shoe, and a plurality of pole shoes are connected to the target seat, and the back plate and the target material are mounted on the target seat, characterized in that: A magnetic conductive sheet is provided under the target seat, and the optimization design method comprises the following steps: S1. First, simulate and analyze the magnetic field distribution on the surface of the rectangular sputtering target; S2, the two ends of the outer magnetic pole are adjusted to a racetrack shape; S3, simulating the magnetic field intensity distribution of inner magnetic poles and outer magnetic poles of different sizes; S4, finally determining and adjusting the heights of the inner magnetic pole and the outer magnetic pole; S5. Simulate the distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets to determine the optimal layout of the magnetic conductive sheets and the design parameters of the magnetron sputtering target; S6. Determine the optimal distance between the two magnetic conductive sheets and adjust it to optimize the cathode magnetic field of the magnetron sputtering.

2. The method for optimizing the design of a rectangular magnetron sputtering cathode magnetic field according to claim 1, characterized in that: The simulation analysis of the magnetic field distribution on the surface of a rectangular sputtering target is as follows: specifically, the target length minus a target width at each end is defined as a straight runway area, the other positions at the two ends are ends, the magnetic field distribution along the x direction in the straight runway area, the uniformity of the horizontal magnetic field along the y direction, and the magnetic field distribution in the end area. For the straight runway area, when it is far away from the end, the magnetic field has only x and z components, the z component refers to the component of the magnetic field in the vertical direction, and the y component is almost zero. When it is close to the end, the y component value increases and changes rapidly with the y direction position. At this time, the y component of the magnetic field has a very significant effect on the horizontal component. Measurement shows that the x component magnetic field intensity at the end position is weaker than that in the straight runway area, and the sputtering etching efficiency of the target is low.

3. The method for optimizing the design of a rectangular magnetron sputtering cathode magnetic field according to claim 1, characterized in that: The simulation of magnetic field strength distribution of inner magnetic poles and outer magnetic poles of different sizes is specifically as follows: five heights of inner magnetic poles and outer magnetic poles are selected, and the five heights of the inner magnetic poles and outer magnetic poles are 15mm, 20mm, 25mm, 30mm, and 35mm, respectively. As the heights of the inner magnetic poles and the outer magnetic poles increase, the parallel magnetic field strength on the target surface also increases, but the increase gradually decreases, and has no effect on the uniformity of the parallel magnetic field strength distribution on the target surface. For every 5mm increase in magnet height, the increase in the maximum parallel magnetic field strength is 8.5%, 11.3%, 7.2%, 3.3%, and 1.6%, respectively. The heights of the inner magnetic poles and the outer magnetic poles can be preliminarily selected based on this, and the optimal height of the inner magnetic poles and the outer magnetic poles is 20mm.

4. The method for optimizing the design of a rectangular magnetron sputtering cathode magnetic field according to claim 1, characterized in that: The simulated distribution of horizontal magnetic induction intensity on the target surface at different distances between the magnetic conductive sheets is as follows: first, the spacing between the magnetic conductive sheet and the inner magnetic pole, and between the magnetic conductive sheet and the outer magnetic pole is set to 2mm, and the distance between the two magnetic conductive sheets on the same side is 1mm, 0.6mm, and 0.2mm. In the process of changing the spacing between the two magnetic conductive sheets from 1mm to 0.2mm, the magnetic induction intensity on the target surface shows obvious changes in the middle area, which plays a major role in regulating the uniformity of the horizontal magnetic induction intensity on the target surface in this area. As the spacing between the two magnetic conductive sheets continues to decrease, the peak value of the horizontal magnetic induction intensity on the target surface continues to decrease. The spacing between the two magnetic conductive sheets is 0.2mm.

5. The method for optimizing the design of a rectangular magnetron sputtering cathode magnetic field according to claim 1, characterized in that: The protective cover is an electromagnetic shielding cover, and the thickness of the target material is 6 mm.

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