Round target material for improving coating uniformity of target material

Abstract

The utility model provides a circular target material for improving the coating uniformity of the target material. The circular target material comprises a central target region and at least two circular ring target regions which are sequentially distributed along the direction far away from the radial direction, and the grain sizes of the central target region and the circular ring target regions are different from each other. According to the utility model, the grain sizes of the central target region and the circular ring target regions are different, so that different textures are formed in different positions, and the problem of poor coating uniformity in the later stage of sputtering caused by different magnet strengths in different positions in the sputtering process of the circular target material is avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of target material preparation, and relates to a circular target material for improving the uniformity of target material coating. Background Art

[0002] At present, semiconductor sputtering targets are used in the production of chips with high integration and fine structures. The uniformity of the coating thickness in chip production has become an important consideration. Magnetron sputtering technology is one of the most commonly used technologies in industrial coating production. It uses a magnetic field to control particles to bombard the surface of the target material. High-energy particles collide with atoms on the surface of the target material, so that the target atoms gain enough energy to escape from the surface, and then are deposited on the surface of the substrate under the action of electric or magnetic field forces to complete the film formation process. When in use, the target material is usually combined with a back plate to form a target assembly, in which the back plate plays a supporting and heat dissipation role. The structure of the target material is an important factor affecting the uniformity of the coating product and the service life of the target material. Improving the structure of the target material is one of the important ways to improve the coating quality and production efficiency.

[0003] CN111411333A discloses a method for improving the uniformity of target coating, which includes: leveling, turning and polishing the welded target in sequence. The purpose of removing the surface stress layer is achieved by improving the target processing technology, improving the poor uniformity of the target coating in the initial sputtering process, and also improving its ability to block the diffusion of Cu atoms of Cu interconnects to other dielectric layers in the manufacture of integrated circuits, thereby improving the performance and life of the device.

[0004] In the prior art, the uniformity of target sputtering coating is mainly improved by improving the uniformity of the overall texture inside the target. However, since most of the existing target materials are cylindrical structures, their structures are relatively large and it is difficult to completely ensure the uniformity of the internal texture, especially for Ta targets. Their different grain orientations and grain sizes have a great influence on the speed and uniformity of their sputtering coating.

[0005] In summary, the design of the target structure needs to be improved as a whole. While significantly improving the uniformity of the target coating, the utilization rate of the target can also be increased to a certain extent. Utility Model Content

[0006] In view of the shortcomings of the prior art, the purpose of the utility model is to provide a circular target material for improving the uniformity of target material coating. By setting the grain sizes of the central target area and each circular target area to be different from each other, different textures are achieved inside the target material at different positions, thereby avoiding the problem of poor uniformity of coating in the later stage of sputtering due to the different magnet strengths at different positions of the circular target material during the sputtering process.

[0007] To achieve this purpose, the utility model adopts the following technical solutions:

[0008] The utility model provides a circular target material for improving the uniformity of target material coating, wherein the circular target material comprises a central target area and at least two annular target areas sequentially distributed away from the radial direction;

[0009] The grain sizes of the central target area and each circular target area are different.

[0010] In the present invention, the number of the circular target areas is ≥ 2, for example, it can be 2, 3, 4, 5, 6 or 7, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0011] In the present invention, the circular target material is a concentric circle target material, and the concentric circles refer to circles with the same center but different radii.

[0012] The utility model provides a circular target material, which comprises a central target area and at least two annular target areas sequentially distributed away from the radial direction. By arranging the entire target material into a structure of many concentric circles, the grain sizes of the central target area and the annular target areas are different from each other, so that each target area has a different internal texture, so that the place with a strong magnetic field has more grain sizes and grain orientations that are not easy to sputter, and the place with a weak magnetic field has more grain sizes and grain orientations that are easy to sputter, so that the probability of the target material being sputtered on the entire sputtering surface is almost the same, thereby effectively improving the uniformity of the target material coating.

[0013] As a preferred technical solution of the present utility model, the number of the circular target areas is 2-4, for example, it can be 2, 3 or 4.

[0014] As a preferred technical solution of the utility model, the radius difference between adjacent circular target areas is 50-100mm, for example, it can be 55mm, 60mm, 65mm, 70mm, 75mm, 80mm, 85mm, 90mm or 95mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0015] As a preferred technical solution of the utility model, the grain size of the central target area is 50-80μm, for example, it can be 55μm, 60μm, 65μm, 70μm, 75μm or 78μm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0016] As a preferred technical solution of the utility model, the grain size of the annular target area is 60-100μm, for example, it can be 65μm, 70μm, 75μm, 80μm, 85μm, 90μm or 95μm, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0017] It is worth noting that the utility model designs different grain sizes at different target area positions of the circular target material to meet the different textures inside at different positions, thereby avoiding the problem of poor coating uniformity in the later stage of sputtering due to the different magnet strengths at different positions during the sputtering process.

[0018] As a preferred technical solution of the utility model, the diameter of the circular target is ≥20 cm, for example, it can be 22 cm, 24 cm, 25 cm, 26 cm, 28 cm, 30 cm or 32 cm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0019] As a preferred technical solution of the utility model, the grain size of the circular target material is 50-100μm, for example, it can be 55μm, 60μm, 65μm, 70μm, 75μm, 80μm, 85μm, 90μm or 95μm, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0020] As a preferred technical solution of the utility model, the circular target includes any one of a tantalum target, an aluminum target, a copper target, an aluminum-copper target or a tantalum-copper target.

[0021] Compared with the prior art, the beneficial effects of the utility model are:

[0022] The utility model provides a circular target material, which comprises a central target area and at least two annular target areas distributed in sequence away from the radial direction. By arranging the entire target material into a structure of many concentric circles, target areas at different positions have different grain sizes and grain orientations, so that each target area has a different internal texture, so that the place with a strong magnetic field has more grain sizes and grain orientations that are not easy to sputter, and the place with a weak magnetic field has more grain sizes and grain orientations that are easy to sputter, so that the probability of the target material being sputtered on the entire sputtering surface is almost the same, thereby effectively improving the uniformity of the target material coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the structure of a circular target material for improving the uniformity of target film coating provided in Example 1;

[0024] Figure 2 This is a schematic diagram of the structure of the circular target material provided for Comparative Example 1. DETAILED DESCRIPTION

[0025] It should be understood that, in the description of the present utility model, the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0026] It should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0027] The technical solution of the utility model is further explained below with reference to the accompanying drawings and through specific implementation methods.

[0028] Example 1

[0029] This embodiment provides a circular target material for improving the uniformity of target film coating. Figure 1 ) includes a central target area and four annular target areas distributed in sequence away from the radial direction;

[0030] The diameter of the circular target is 25 cm; the circular target is an aluminum-copper target;

[0031] The radius difference between adjacent circular target areas is 50-60 mm;

[0032] The grain size of the central target area is 50-65 μm; the grain size of the annular target area is 70-80 μm.

[0033] The circular target material provided in this embodiment can avoid the problem of poor coating uniformity in the later stage of sputtering due to the different strengths of magnets at different positions during the sputtering process.

[0034] Example 2

[0035] This embodiment provides a circular target material for improving the uniformity of target film coating, wherein the circular target material comprises a central target area and two annular target areas sequentially distributed away from the radial direction;

[0036] The diameter of the circular target is 20 cm; the circular target is a tantalum target;

[0037] The radius difference between adjacent circular target areas is 70-80 mm;

[0038] The grain size of the central target area is 60-80 μm; the grain size of the annular target area is 75-95 μm.

[0039] The circular target material provided in this embodiment can avoid the problem of poor coating uniformity in the later stage of sputtering due to the different strengths of magnets at different positions during the sputtering process.

[0040] Example 3

[0041] This embodiment provides a circular target material for improving the uniformity of target film coating, wherein the circular target material comprises a central target area and five circular target areas sequentially distributed away from the radial direction;

[0042] The diameter of the circular target is 26 cm; the circular target is a copper target;

[0043] The radius difference between adjacent circular target areas is 50-70 mm;

[0044] The grain size of the central target area is 55-80 μm; the grain size of the annular target area is 70-95 μm.

[0045] The circular target material provided in this embodiment can avoid the problem of poor coating uniformity in the later stage of sputtering due to the different strengths of magnets at different positions during the sputtering process.

[0046] Comparative Example 1

[0047] This comparative example provides a circular target material, except that the circular target material (such as Figure 2 Except that (as shown) only one target area is included and the grain sizes in the target area are all the same value, other conditions are the same as those in Example 1.

[0048] Because the target material is not designed as a concentric circle structure, the grain size at each position is the same, which does not satisfy the different textures inside the target material at different positions, resulting in poor coating uniformity during the sputtering process.

[0049] The applicant declares that the above is only a specific implementation method of the present utility model, but the protection scope of the present utility model is not limited thereto. The technicians in the relevant technical field should understand that any changes or substitutions that can be easily thought of by the technicians in the relevant technical field within the technical scope disclosed in the present utility model fall within the protection scope and disclosure scope of the present utility model.

Claims

1. A circular target material for improving the uniformity of target coating, characterized in that: The circular target material includes a central target area and at least two annular target areas sequentially distributed away from the radial direction; The grain sizes of the central target area and each circular target area are different.

2. The circular target material for improving target coating uniformity according to claim 1, characterized in that: The number of the circular target areas is 2-4.

3. The circular target material for improving target coating uniformity according to claim 1, characterized in that: The radius difference between adjacent circular target areas is 50-100 mm.

4. The circular target material for improving target coating uniformity according to claim 1, characterized in that: The grain size of the central target area is 50-80 μm.

5. The circular target material for improving target coating uniformity according to claim 1, characterized in that: The grain size of the annular target area is 60-100 μm.

6. The circular target material for improving target coating uniformity according to claim 1, characterized in that: The diameter of the circular target is ≥20 cm.

7. The circular target material for improving target coating uniformity according to claim 1, characterized in that: The grain size of the circular target material is 50-100 μm.

8. The circular target material for improving target coating uniformity according to claim 1, characterized in that: The circular target includes any one of a tantalum target, an aluminum target, a copper target, an aluminum-copper target or a tantalum-copper target.

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