CN211112196U - A magnetic source structure of magnetron sputtering cathode - Google Patents

Abstract

The utility model provides a magnetic source structure of a magnetron sputtering cathode. The magnetic source structure includes a cathode target and a magnet assembly, the magnet assembly is arranged below the cathode target; the magnet assembly includes a transverse magnet and a longitudinal magnet, The transverse magnets and longitudinal magnets are alternately arranged, the magnetic poles of adjacent longitudinal magnets are opposite, and the magnetic poles of adjacent longitudinal magnets and transverse magnets are the same. The magnetic source structure of the present invention effectively enhances the magnetic field strength near the surface of the cathode target by adding transverse magnets on the basis of conventional magnets, and through the arrangement of transverse magnets and longitudinal magnets; Adjustability can effectively change the distribution of the magnetic field on the surface of the target, enhance the uniformity and consistency of the magnetic field distribution, so that the target can be uniformly consumed during magnetron sputtering, and the quality of the coating can be improved.

Description

A magnetic source structure of magnetron sputtering cathode

technical field

The utility model belongs to the technical field of magnetron sputtering coating, and relates to a magnetic source structure of a magnetron sputtering cathode.

Background technique

Magnetron sputtering is one of the physical vapor deposition (PVD) methods. The general sputtering method can be used to prepare various materials such as metals, semiconductors, insulators, etc., and has the advantages of simple equipment, easy control, large coating area and adhesion. strong and other advantages. The magnetron sputtering method developed in the 1970s has achieved high speed, low temperature and low damage. Since high-speed sputtering is carried out under low pressure conditions, the ionization rate of the gas must be effectively increased, while magnetron sputtering introduces a magnetic field on the surface of the target cathode and uses the magnetic field to confine charged particles to increase the plasma density to increase the sputtering. emissivity. Since the development of magnetron sputtering technology, it has been widely used in semiconductors, magnetic recording hard disk media, radio frequency MEMS, flat panel displays and other fields.

In the existing magnetron sputtering system, the coating substrate is located above the target, a permanent magnet is arranged below the target to generate a magnetic field, and a pole plate is below the magnet. Ionization produces Ar ions and electrons. Ar ions fly to the cathode target, bombard the target with high energy, and sputter the target. During the sputtering process, neutral target atoms or molecules are deposited on the substrate to form a thin film. During this process, the magnetic field lines confine the electrons near the surface of the target material, prolonging the trajectory of the electrons in the plasma, increasing the probability of the electrons colliding with argon gas molecules and ionizing the process, thereby improving the efficiency of thin film growth. However, most of the magnets currently used are bar magnets, and the surface magnetic flux intensity at both ends of the bar magnet is often larger than the surface magnetic flux intensity in the middle. The service life of the target is reduced, and the cost of the process and raw materials is increased.

CN 103046009A discloses a planar magnetron sputtering cathode, which includes a target, a magnet device and a magnetic shoe, the magnet device is installed on the back of the target, and the magnet device includes three first parallel and spaced apart The magnets are respectively arranged on both sides and the middle of the target material, the magnet device further includes four second magnets, which are arranged in pairs between two adjacent first magnets, and the adjacent first magnets in the magnet device The polarity arrangement of one magnet is opposite to that of the second magnet, and the polarity arrangement of two adjacent second magnets is opposite. Although this method can make the magnetic field intensity distribution more uniform to a certain extent, all the magnets are still arranged vertically, the uniformity of the magnetic field intensity distribution still cannot meet the requirements, and the magnetic field distribution cannot be changed.

CN 107083537A discloses a planar magnetron sputtering cathode, the planar magnetron sputtering cathode comprises a target material, a back plate, a magnet device and a magnetic conducting plate, the target material is arranged on one side of the back plate, and the magnetic conducting plate is arranged on the back On the other side of the plate, the magnet device is arranged between the back plate and the magnetic conducting plate; wherein, the magnet device includes a middle magnet and an outer magnet surrounding the middle magnet, the middle magnet includes at least two electromagnets, the outer magnet and the middle magnet The magnets facing the target have opposite polarities; the magnets in this magnet device are still set vertically, and the change of the magnetic field depends on whether it is energized or not, and it is difficult to adjust. to interfere, and there are requirements for the type of magnet.

To sum up, the arrangement of the magnets in the magnetron sputtering cathode also needs to be able to make the magnetic field intensity distribution more uniform, and at the same time, it can also be adjusted in time according to the sputtering process to maintain the uniform distribution of the magnetic field.

Utility model content

In view of the problems existing in the prior art, the purpose of the present invention is to provide a magnetic source structure of a magnetron sputtering cathode, which can effectively enhance the magnetic field near the surface of the cathode target by adding a transverse magnet on the basis of a conventional magnet. The strength of the magnetic field, and the distribution of the magnetic field on the surface of the target can be changed by adjusting the position of the transverse magnet, and the uniformity of the magnetic field distribution can be enhanced, thereby improving the rate and quality of the magnetron sputtering coating.

For this purpose, the utility model adopts the following technical solutions:

The utility model provides a magnetic source structure of a magnetron sputtering cathode. The magnetic source structure comprises a cathode target and a magnet assembly, and the magnet assembly is arranged below the cathode target;

The magnet assembly includes transverse magnets and longitudinal magnets, the transverse magnets and longitudinal magnets are alternately arranged, the magnetic poles of adjacent longitudinal magnets are opposite, and the magnetic poles of adjacent longitudinal magnets and transverse magnets are the same.

In the present utility model, the magnetic source structure of the magnetron sputtering cathode is mainly based on the original longitudinal magnet, and the transverse magnet is arranged in the interval area, and the arrangement of the magnet and the arrangement of the magnetic pole direction enhance the surface of the cathode target. At the same time, the position of the transverse magnet can be adjusted, that is, the distribution of the magnetic field near the target surface of the cathode can be adjusted by changing the distance from the target, so as to provide a uniform magnetic field as much as possible, so that the target can be Uniform etching consumption, improve the quality of the coating, reduce the difficulty of magnetron sputtering.

The following are the preferred technical solutions of the present invention, but not as limitations of the technical solutions provided by the present invention. Through the following technical solutions, the technical purposes and beneficial effects of the present invention can be better achieved and realized.

As a preferred technical solution of the present invention, the magnet is a bar magnet.

Preferably, the transverse magnets are movable in the longitudinal direction within the spaced region between two adjacent longitudinal magnets.

Preferably, the moving distance of the transverse magnet does not exceed half of the height of the longitudinal magnet, such as 1/12, 1/8, 1/4, 1/3, 3/8 or 1/2, etc., but not limited to those listed value, other non-recited values within this value range also apply.

In the utility model, the distance between the transverse magnet and the target can be adjusted, so as to adjust the magnetic field distribution on the surface of the cathode target. Therefore, the position of the transverse magnet should be properly adjusted to keep the magnetic field strength and distribution in line with the conditions of magnetron sputtering, so that the cathode target can be etched uniformly; the specific moving distance of the transverse magnet is related to the target and the size related.

As a preferred technical solution of the present invention, the included angle between the transverse magnet and the horizontal direction is 0 to 5 degrees, such as 0, 1, 2, 3, 4, or 5 degrees, but not limited to Recited values apply equally well to other non-recited values within that range.

Preferably, the included angle between the longitudinal magnet and the vertical direction is 0 to 5 degrees, such as 0, 1, 2, 3, 4, or 5 degrees, etc., but is not limited to the listed values. The same applies to other non-recited values within the numerical range.

In the present invention, the setting of the inclination angles of the transverse magnet and the longitudinal magnet is to ensure the uniformity of the horizontal component of the magnetic field near the target, and the two cooperate with each other to achieve a better adjustment effect.

As a preferred technical solution of the present invention, the cathode target is a flat target.

Preferably, the cathode target includes a circular target and/or a square target.

Preferably, the longitudinal magnet includes a middle magnet and an outer magnet surrounding the middle magnet, and the outer magnet is provided with at least one circle.

Preferably, transverse magnets are correspondingly arranged between two adjacent outer ring magnets, and between the outer ring magnets and the middle magnet.

In this utility model, in order to ensure the uniformity of the magnetic field, the magnets are generally arranged symmetrically and regularly, and at the same time coordinate the positional relationship between the transverse magnet and the longitudinal magnet; Then it is determined according to the size of the target material and the magnet, and a transverse magnet is arranged between the two longitudinal magnets.

As a preferred technical solution of the present invention, the material of the magnet is a permanent magnet material.

Preferably, the permanent magnet material comprises any one or a combination of at least two of sintered NdFeB, samarium cobalt or sintered ferrite. Typical but non-limiting examples of the combination include: sintered NdFeB and sintered ferrite. The combination of samarium cobalt, the combination of sintered samarium cobalt and sintered ferrite, the combination of sintered NdFeB, the combination of sintered samarium cobalt and sintered ferrite, etc.

In the utility model, the permanent magnet material mainly includes alloy permanent magnet material and ferrite permanent magnet material, among which rare earth permanent magnet material is an important component of alloy permanent magnet material, sintered NdFeB and sintered samarium cobalt are all rare earth permanent magnets Material.

As a preferred technical solution of the present invention, the magnetic source structure further includes a magnetic conductive component, and the magnetic conductive component is arranged above the side of the cathode target.

Preferably, the material of the magnetically conductive component includes magnetically conductive steel, and specifically, various types of alloy steel can be selected, such as 45-gauge steel, 10-gauge steel, 403 stainless steel or 430 stainless steel.

As a preferred technical solution of the present invention, the magnetic source structure further includes a base, and the magnet assembly is arranged on the base.

Preferably, a magnetic shielding layer is provided around and on the bottom side of the magnetic source structure, and the magnetic shielding layer is not in direct contact with the magnetic source structure.

In the present invention, the magnetron sputtering cathode includes a base, a casing, a cooling assembly, a rotating assembly, etc. in addition to the cathode target and the magnet assembly, which are all matching assemblies of the conventional cathode target, and will not be described in detail.

The utility model also provides a method for adjusting the magnetic field of the above-mentioned magnetic source structure, the method comprising:

(1) assemble according to the magnetic source structure, and fix the initial position of the transverse magnet, so that the horizontal component of the magnetic field near the cathode target surface is uniform;

(2) With the progress of the magnetron sputtering process, the thickness of the cathode target decreases, the position of the transverse magnet is adjusted in the longitudinal direction, and the size of the horizontal component of the magnetic field near the cathode target surface is adjusted and maintained uniform.

During the assembly process of the magnetic source structure, the magnet assemblies are arranged and assembled by means of bonding or mechanical fixing.

During the magnetron sputtering process, the magnet assembly rotates as a whole.

In the present invention, the magnet assembly generally rotates during the magnetron sputtering process to ensure the uniformity of the magnetic field in the target plane, and also contribute to the uniform etching of the target and improve the sputtering efficiency.

Preferably, the adjustment range of the transverse magnet is from the position where the upper end of the transverse magnet is flush with the upper end of the longitudinal magnet to the position where the lower end of the transverse magnet does not exceed the middle position of the longitudinal magnet.

Compared with the prior art, the utility model has the following beneficial effects:

(1) The magnetic source structure of the present utility model effectively enhances the magnetic field intensity near the surface of the cathode target by adding transverse magnets on the basis of conventional magnets, and through the arrangement of transverse magnets and longitudinal magnets;

(2) The adjustability of the position of the transverse magnet in the magnetic source structure of the present invention can effectively change the distribution of the magnetic field on the surface of the target material, enhance the uniformity and consistency of the magnetic field distribution, and make the target material during magnetron sputtering. It can be consumed evenly and improve the coating quality.

Description of drawings

1 is a schematic structural diagram of a magnetron sputtering cathode magnetic source structure provided in Embodiment 1 of the present invention;

2 is a schematic structural diagram of a magnetron sputtering cathode magnetic source structure provided by Comparative Example 1 of the present utility model;

Fig. 3 is the magnetic field horizontal component intensity curve of the magnetic source structure cathode target surface that the utility model embodiment 1 and the comparative example 1 provide;

Fig. 4 is the magnetic field horizontal component intensity curve of the surface of the cathode target after the magnet position adjustment in Example 4, Comparative Example 2 and Comparative Example 3 of the present utility model;

Among them, 1-cathode target, 2-transverse magnet, 3-longitudinal magnet, 4-magnetic shielding layer, 5-magnetic conductive component.

Detailed ways

In order to better illustrate the present utility model and facilitate the understanding of the technical solutions of the present utility model, the present utility model is described in further detail below, but the following embodiments are only simple examples of the present utility model, and do not represent or limit the present utility model. The protection scope of the rights, the protection scope of the present invention is subject to the claims.

The specific embodiment of the present invention partially provides a magnetic source structure of a magnetron sputtering cathode, the magnetic source structure includes a cathode target 1 and a magnet assembly, and the magnet assembly is arranged below the cathode target 1;

The magnet assembly includes transverse magnets 2 and longitudinal magnets 3, the transverse magnets 2 and longitudinal magnets 3 are alternately arranged, the magnetic poles of adjacent longitudinal magnets 3 are opposite, and the magnetic poles of adjacent longitudinal magnets 3 and transverse magnets 2 are the same.

The following are typical but non-limiting examples of the present utility model:

Example 1:

The present embodiment provides a magnetic source structure for a magnetron sputtering cathode. A schematic structural diagram of the magnetic source structure is shown in FIG. 1 , including a cathode target 1 and a magnet assembly, and the magnet assembly is disposed below the cathode target 1 ;

The magnet assembly includes transverse magnets 2 and longitudinal magnets 3, the transverse magnets 2 and longitudinal magnets 3 are alternately arranged, the magnetic poles of adjacent longitudinal magnets 3 are opposite, and the magnetic poles of adjacent longitudinal magnets 3 and transverse magnets 2 are the same.

The magnet is a bar magnet, and the material is sintered NdFeB.

The transverse magnet 2 can move in the longitudinal direction within the interval area between two adjacent longitudinal magnets 3 ; the moving distance of the transverse magnet 2 is 3/8 of the height of the longitudinal magnet 3 .

The angle between the transverse magnet 2 and the horizontal direction is 0 degree, and the angle between the longitudinal magnet 3 and the vertical direction is 0 degree.

The cathode target 1 is a flat target, the cathode target 1 is a circular target, and the longitudinal magnet 3 includes a middle magnet and an outer magnet surrounding the middle magnet. A circle of transverse magnets 2 is correspondingly disposed between the magnet and the intermediate magnet.

The magnetic source structure further includes a base, and the magnet assembly is arranged on the base.

A magnetic shielding layer 4 is provided around and on the bottom side of the magnetic source structure, and the magnetic shielding layer 4 is not in direct contact with the magnetic source structure.

The magnetic source structure further includes a magnetic conductive component 5 , and the magnetic conductive component 5 is disposed above the side of the cathode target 1 and above the side surface of the magnetic shielding layer 4 .

Example 2:

This embodiment provides a magnetic source structure of a magnetron sputtering cathode, the magnetic source structure includes a cathode target 1 and a magnet assembly, and the magnet assembly is arranged below the cathode target 1;

The magnet assembly includes transverse magnets 2 and longitudinal magnets 3, the transverse magnets 2 and longitudinal magnets 3 are alternately arranged, the magnetic poles of adjacent longitudinal magnets 3 are opposite, and the magnetic poles of adjacent longitudinal magnets 3 and transverse magnets 2 are the same.

The magnet is a bar magnet, and the material is sintered ferrite.

The transverse magnet 2 can move longitudinally in the interval area between two adjacent longitudinal magnets 3 ; the moving distance of the transverse magnet 2 is 1/4 of the height of the longitudinal magnet 3 .

The angle between the transverse magnet 2 and the horizontal direction is 2 degrees, and the angle between the longitudinal magnet 3 and the vertical direction is 2 degrees.

The cathode target 1 is a flat target, the cathode target 1 is a circular target, and the longitudinal magnet 3 includes a middle magnet and an outer magnet surrounding the middle magnet. A ring of transverse magnets 2 is correspondingly provided between the outer ring magnets and between the outer ring magnets and the middle magnet.

The magnetic source structure further includes a base, and the magnet assembly is arranged on the base.

A magnetic shielding layer 4 is provided around and on the bottom side of the magnetic source structure, and the magnetic shielding layer 4 is not in direct contact with the magnetic source structure.

Example 3:

This embodiment provides a magnetic source structure of a magnetron sputtering cathode, the magnetic source structure includes a cathode target 1 and a magnet assembly, and the magnet assembly is arranged below the cathode target 1;

The magnet assembly includes transverse magnets 2 and longitudinal magnets 3, the transverse magnets 2 and longitudinal magnets 3 are alternately arranged, the magnetic poles of adjacent longitudinal magnets 3 are opposite, and the magnetic poles of adjacent longitudinal magnets 3 and transverse magnets 2 are the same.

The magnet is a bar magnet, and the material is sintered samarium cobalt.

The transverse magnet 2 can move in the longitudinal direction within the interval area between two adjacent longitudinal magnets 3 ; the moving distance of the transverse magnet 2 is 1/8 of the height of the longitudinal magnet 3 .

The included angle between the transverse magnet 2 and the horizontal direction is 5 degrees, and the included angle between the longitudinal magnet 3 and the vertical direction is 5 degrees.

The cathode target 1 is a flat target, the cathode target 1 is a rectangular target, and the longitudinal magnet 3 includes an intermediate magnet and a peripheral magnet surrounding the intermediate magnet. A circle of transverse magnets 2 are correspondingly arranged therebetween.

The magnetic source structure further includes a base, and the magnet assembly is arranged on the base.

A magnetic shielding layer 4 is provided around and on the bottom side of the magnetic source structure, and the magnetic shielding layer 4 is not in direct contact with the magnetic source structure.

The magnetic source structure further includes a magnetic conductive component 5 , and the magnetic conductive component 5 is disposed above the side of the cathode target 1 and above the side surface of the magnetic shielding layer 4 .

Comparative Example 1:

This comparative example provides a magnetic source structure of a magnetron sputtering cathode. The schematic structural diagram of the magnetic source structure is shown in FIG. 2 , which refers to the structure in Example 1, the only difference is that the magnet assembly does not include The transverse magnet 2 is only provided with longitudinal magnets.

After assembling the magnetic source structures of Example 1 and Comparative Example 1, the horizontal component of the magnetic field on the surface of the cathode target was simulated and measured, and the results are shown in FIG. 3 .

As can be seen from FIG. 3 , after the transverse magnet is added to the magnetic source structure, the horizontal component of the magnetic field on the surface of the cathode target can be greatly enhanced.

Example 4:

This embodiment provides a method for adjusting the magnetic field of a magnetron sputtering cathode magnetic source structure, where the magnetic source structure adopts the structure in Embodiment 1, and the method includes:

(1) Assemble according to the magnetic source structure in Example 1. The magnet assemblies are arranged and assembled in a mechanically fixed manner. The diameter of the cathode target 1 is 40 mm, and the initial position of the transverse magnet 2 is fixed, so that the magnetic field near the surface of the cathode target 1 is fixed. The horizontal component is uniform;

(2) During the magnetron sputtering process, the magnet assembly rotates as a whole, the thickness of the cathode target 1 decreases, the position of the transverse magnet 2 is adjusted longitudinally, and the size of the horizontal component of the magnetic field near the surface of the cathode target 1 is adjusted and maintained uniform.

Comparative Example 2:

This comparative example provides a method for adjusting the magnetic field of a magnetron sputtering cathode magnetic source structure, the magnetic source structure adopts the structure in Example 1, and the method refers to the method in Example 4, the difference only lies in: the steps ( 2) As the sputtering process proceeds, the overall position of the magnet assembly is adjusted in the longitudinal direction.

Comparative Example 3:

This comparative example provides a method for adjusting the magnetic field of a magnetron sputtering cathode magnetic source structure, the magnetic source structure adopts the structure in Comparative Example 1, and the method includes:

(1) Assemble according to the magnetic source structure in Comparative Example 1, the magnet assemblies are arranged and assembled in a mechanically fixed manner, and the diameter of the cathode target 1 is 40 mm;

(2) During the magnetron sputtering process, the magnet assembly rotates as a whole, the thickness of the cathode target 1 decreases, the position of the longitudinal magnet 3 is adjusted longitudinally, and the magnitude of the horizontal component of the magnetic field near the surface of the cathode target 1 is adjusted.

During the sputtering in Example 4 and Comparative Examples 2-3, after timely feedback and adjustment of the magnet position, the horizontal component of the magnetic field on the surface of the cathode target was simulated and measured, and the results are shown in FIG. 4 .

It can be seen from Figure 4 that with the progress of magnetron sputtering, the position of the magnet needs to be adjusted after the thickness of the target becomes thinner. In Comparative Example 3, only the position of the longitudinal magnet can be adjusted, and its magnetic field strength is the smallest.

Combining the above embodiments and comparative examples, it can be seen that the magnetic source structure of the present invention effectively enhances the magnetic field intensity near the surface of the cathode target by adding transverse magnets on the basis of conventional magnets, and through the arrangement of transverse magnets and longitudinal magnets ; The adjustability of the position of the transverse magnet in the magnetic source structure can effectively change the distribution of the magnetic field on the surface of the target material, enhance the uniformity and consistency of the magnetic field distribution, so that the target material can be uniformly consumed during magnetron sputtering, improving coating quality.

The applicant declares that the present utility model illustrates the detailed structure of the present utility model through the above-mentioned embodiments, but the present utility model is not limited to the above-mentioned detailed structure, that is, it does not mean that the present utility model must rely on the above-mentioned detailed structure to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the structure of the present invention, addition of auxiliary structures, selection of specific methods, etc., all fall within the scope of protection and disclosure of the present invention. .

Claims (10)

1. A magnetic source structure of a magnetron sputtering cathode is characterized by comprising a cathode target and a magnet assembly, wherein the magnet assembly is arranged below the cathode target;

the magnet assembly comprises transverse magnets and longitudinal magnets, the transverse magnets and the longitudinal magnets are arranged alternately, the magnetic poles of the adjacent longitudinal magnets are opposite, and the magnetic poles of the adjacent longitudinal magnets and the magnetic poles of the adjacent transverse magnets are the same.

2. The magnetic source structure of a magnetron sputtering cathode according to claim 1, wherein said magnet is a bar magnet.

3. The magnetic source structure of a magnetron sputtering cathode according to claim 1, wherein said transverse magnets move in a longitudinal direction in a spaced area of two adjacent longitudinal magnets;

the moving distance of the transverse magnet is not more than half of the height of the longitudinal magnet.

4. The magnetic source structure of the magnetron sputtering cathode according to claim 1, wherein an angle between the transverse magnet and a horizontal direction is 0 to 5 degrees;

the included angle between the longitudinal magnet and the vertical direction is 0-5 degrees.

5. The magnetic source structure of the magnetron sputtering cathode according to claim 1, wherein the cathode target is a planar circular target and/or a planar square target.

6. The magnetic source structure of a magnetron sputtering cathode according to claim 5, wherein said longitudinal magnets comprise a middle magnet and an outer ring magnet surrounding said middle magnet, said outer ring magnet being provided with at least one turn.

7. The magnetic source structure of the magnetron sputtering cathode according to claim 6, wherein a transverse magnet is correspondingly arranged between two adjacent circles of outer ring magnets and between the outer ring magnets and the middle magnet.

8. The magnetic source structure of a magnetron sputtering cathode according to claim 1, further comprising a magnetically conductive assembly disposed laterally over said cathode target.

9. The magnetic source structure of a magnetron sputtering cathode according to claim 1, further comprising a base on which the magnet assembly is disposed.

10. The magnetic source structure of the magnetron sputtering cathode according to claim 1, wherein the magnetic source structure is provided with magnetic shielding layers on the periphery and the bottom side, and the magnetic shielding layers are not in direct contact with the magnetic source structure.

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