A multi-wafer electroplating cell
By setting up multiple independent anode areas and wafer fixtures in the electroplating tank, multi-wafer electroplating can be achieved, solving the problems of low efficiency and high cost of small-sized wafer electroplating and achieving efficient and uniform electroplating results.
Patent Information
- Application Number
- CN202521385448.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-02
- Publication Date
- 2026-08-04
- Estimated Expiration
- 2035-07-02
AI Technical Summary
In existing technologies, single-sided electroplating processes for 4-inch and smaller wafers are inefficient and costly, making it difficult to achieve high-efficiency electroplating.
Design a multi-wafer electroplating tank, comprising an electroplating tank body, wafer clamps, a drive assembly, a stirring paddle, and an anode. By setting multiple independent anode zones and wafer clamps within the electroplating tank, the number of wafers that can be clamped at one time is increased. A paddle is set in each anode zone for stirring to ensure the uniformity of the electroplating solution.
It increases electroplating output and efficiency, reduces costs, ensures uniform coating thickness, and improves the fixation effect.
Smart Images
Figure CN224591060U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of electroplating equipment technology, specifically to a multi-wafer electroplating tank. Background Technology
[0002] In the production process of semiconductor integrated circuits, it is necessary to electroplate the surface of the wafer to form a metal layer. Therefore, wafer electroplating is one of the key steps in the semiconductor wafer manufacturing process. The process involves placing the wafer in an electroplating solution, connecting a negative voltage to the wafer as a cathode, and connecting a positive voltage to a soluble or insoluble anode. Through the action of an electric field, metal ions in the electroplating solution are deposited onto the wafer surface.
[0003] Currently, most wafer plating processes use single-sided plating, meaning a single fixture can typically hold only one wafer, or one wafer on each side. For large wafers of 8 inches or larger, single-wafer clamping is acceptable; however, for wafers of 4 inches or smaller, this method is inefficient and costly. Utility Model Content
[0004] The technical problem to be solved by this utility model is how to improve the output and efficiency of electroplating and reduce costs.
[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution:
[0006] A multi-wafer electroplating tank includes an electroplating tank body, a wafer fixture, a drive assembly, a stirring paddle, paddle blades, and an anode. The wafer fixture is located at the center of the electroplating tank body, causing the electroplating tank body to be divided into two parts. Multiple electroplating sub-tanks are arranged along the length of the wafer fixture within the electroplating tank body on both sides of the wafer fixture. Each electroplating sub-tank is divided into an anode area and an overflow area by a partition. The anode area is located close to the wafer fixture. The output end of the drive assembly is connected to two sets of stirring paddles that can move linearly on the electroplating tank body. The two sets of stirring paddles are respectively located on both sides of the wafer fixture. Each stirring paddle above the anode area is provided with a blade. The drive assembly drives the blades to move within the anode area through the stirring paddles. An anode is provided in each anode area.
[0007] By setting up multiple independent anode zones and wafer clamps in the electroplating tank, the number of wafers that can be clamped at one time is increased, enabling electroplating of multiple wafers at a time. This improves the output and efficiency of electroplating, reduces costs, and allows for the addition of paddles in each anode zone to stir the electroplating solution near the wafers in each zone. This achieves uniform electroplating solution and reduces the thickness of the interface layer on the wafer surface, ensuring uniform coating thickness.
[0008] Preferably, the wafer fixture includes a fixture body and a clamping mechanism. Multiple clamping mechanisms are provided on both ends of the fixture body. The clamping mechanism includes a spring clip, which is connected to the fixture body by a torsion spring.
[0009] Preferably, the clamping mechanism further includes a conductive probe, through which the spring clip abuts against the wafer.
[0010] Preferably, the spring clip includes a first spring clip, a second spring clip, and a third spring clip arranged sequentially along the length of the clamp body, and the free ends of the first spring clip, the second spring clip, and the third spring clip are all fixedly connected to conductive probes.
[0011] Preferably, the conductive probe includes a first conductive probe, a second conductive probe, and a third conductive probe, which are respectively fixedly connected to the top of the first spring clip, the second spring clip, and the third spring clip.
[0012] Preferably, the drive assembly includes a fixed plate, a drive motor, a rotating block, a fisheye connecting rod, and a fixed rod. The fixed plate is fixed to the outside of the electroplating tank body, the drive motor is fixed to the fixed plate, the output end of the drive motor is connected to the rotating block, one end of the fisheye connecting rod is hinged to the rotating block, and the other end is hinged to the fixed rod. The fixed rod is fixedly connected to two sets of stirring paddles, and the center of the connection between the fisheye connecting rod and the rotating block is eccentrically set with respect to the center of the output end of the drive motor.
[0013] Preferably, the top of the partition has a wavy structure.
[0014] Preferably, a shielding plate is also provided in the anode zone between the agitator and the anode.
[0015] Preferably, the thickness of the shielding plate is not less than 40 mm.
[0016] Compared with the prior art, the beneficial effects of this utility model are:
[0017] 1. By setting up multiple independent anode zones and wafer clamps in the electroplating tank, the number of wafers that can be clamped at one time is increased, enabling electroplating of multiple wafers at a time. This improves the output and efficiency of electroplating, reduces costs, and provides paddles in each anode zone to stir the electroplating solution near the wafers in each zone. This achieves uniform electroplating solution and reduces the thickness of the interface layer on the wafer surface, ensuring uniform coating thickness.
[0018] 2. The wafer is fixed by multiple conductive probes, which improves the fixing effect. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the structure of an embodiment of the present utility model;
[0020] Figure 2 This is a schematic diagram of the structure of the electroplating tank body according to an embodiment of the present invention;
[0021] Figure 3This is a schematic diagram of the structure of the wafer fixture according to an embodiment of the present invention;
[0022] Figure 4 This is another structural schematic diagram of the wafer fixture according to an embodiment of the present invention;
[0023] Figure 5 for Figure 4 Enlarged view of A in the middle;
[0024] Figure 6 This is a side view of the wafer fixture according to an embodiment of the present invention;
[0025] Figure 7 This is a schematic diagram of the fixture body according to an embodiment of the present utility model. Detailed Implementation
[0026] To facilitate understanding of the technical solution of this utility model by those skilled in the art, the technical solution of this utility model will now be further described in conjunction with the accompanying drawings.
[0027] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0028] In this application, unless otherwise expressly specified and limited, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise expressly and specifically limited.
[0029] See Figure 1 and Figure 2 This embodiment discloses a multi-wafer electroplating tank, including an electroplating tank body 1, a wafer clamp 2, a drive assembly 3, a stirring paddle 4, a paddle blade 5, and an anode 6.
[0030] The wafer fixture 2 is positioned at the center of the electroplating tank body 1, causing the electroplating tank body 1 to be divided into two. Multiple electroplating sub-tanks are arranged in the electroplating tank body 1 on both sides of the wafer fixture 2 along the length direction of the wafer fixture 2. In this embodiment, each side of the electroplating tank body 1 is provided with three electroplating sub-tanks, but not limited to three. The number of electroplating sub-tanks can be set according to actual needs.
[0031] Each electroplating sub-tank is divided into an anode zone 1011 and an overflow zone 1012 by a partition 7. The top of the partition 7 has a wavy structure. The anode zone 1011 is located close to the wafer fixture 2. An electroplating solution inlet is opened at the bottom of each anode zone 1011, and an electroplating solution outlet is opened at the bottom of one of the overflow zones 1012 on the same side. The overflow zones 1012 on the same side are interconnected. Specifically, the electroplating solution is injected into the anode zone 1011 through the electroplating solution inlet. When the height of the electroplating solution in the anode zone 1011 exceeds the partition 7, it overflows into the overflow zone 1012. The electroplating solution in the overflow zone 1012 on the same side is discharged from the electroplating solution outlet.
[0032] See Figures 3 to 6 The wafer jig 2 includes a jig body 21, a clamping mechanism, and a conductive plate 23. The jig body 21 is fixed on the electroplating tank 1. Multiple clamping mechanisms are provided on both ends of the jig body 21. The conductive plate 23 is fixedly connected to the top of the jig body 21. The conductive plate 23 is electrically connected to the conductive probe through a flexible wire. The clamping mechanism includes a spring clip 22 and a conductive probe 24. The spring clip 22 is connected to the jig body 21 through a torsion spring (not shown in the figure) and causes the wafer 9 to abut against the jig body 21 through the conductive probe 24. In this embodiment, the wafer 9 is a 4-inch circular wafer, but it is not limited to a 4-inch wafer. Jigs of different sizes can be designed according to actual needs. They are also not limited to circular shapes. They can also be designed as electroplating square workpieces or other shaped workpieces according to actual needs.
[0033] Specifically, a through hole adapted to the torsion spring is opened on the fixture body 21, a rotating shaft is provided in the through hole, the torsion spring is sleeved on the rotating shaft, and the two ends of the torsion spring are respectively fixedly connected to the spring clips 22 located on the two ends of the fixture body 21.
[0034] In this embodiment, the wafer jig 2 is designed with six clamping mechanisms, but it can also be designed with two, four, or eight clamping mechanisms, but it is not limited to these. The number of clamping mechanisms can be increased according to actual needs. Taking one end face of the jig body 21 as an example, the spring clip 22 includes a first spring clip 221, a second spring clip 222, and a third spring clip 223 that are linearly and equidistantly distributed along the length of the jig body 21. The free ends of the first spring clip 221, the second spring clip 222, and the third spring clip 223 are all fixedly connected to conductive probes 24. The second spring clip 222 is located between the first spring clip 221 and the third spring clip 223. 222 can drive the first spring clip 221 and the third spring clip 223 to rotate synchronously relative to the clamp body 21. The second spring clip 222 has transmission blocks 2221 at both ends facing the first spring clip 221 and the third spring clip 223. The first spring clip 221 and the third spring clip 223 have steps 2222 that abut against the transmission blocks 2221 at one end facing the second spring clip 222. The bottom end of the transmission block 2221 abuts against the step 2222, and the bottom end of the transmission block 2221 is located above the top of the step 2222. By pressing the second spring clip 222, the first spring clip 221 and the third spring clip 223 can be driven to rotate synchronously.
[0035] The conductive probe 24 includes a first conductive probe 241, a second conductive probe 242, and a third conductive probe 243. The first conductive probe 241, the second conductive probe 242, and the third conductive probe 243 are respectively fixedly connected to the top of the first spring clip 221, the second spring clip 222, and the third spring clip 223. The lines connecting the points of the first conductive probe 241, the second conductive probe 242, and the third conductive probe 243 in contact with the workpiece to be electroplated form a triangle, and the lengths of the first conductive probe 241 and the third conductive probe 243 are greater than that of the second conductive probe 242.
[0036] For further details, please refer to [link / reference]. Figure 7 In this embodiment, the fixture body 21 is provided with a slot 2101 that can hold the wafer 9. The slot 2101 has multiple water channels inside. The slot 2101 is used to position the wafer 9. The water channels contain fluid that will adsorb the wafer 9 on the slot 2101 to prevent the wafer 9 from falling off.
[0037] In reference Figure 1The output end of the drive assembly 3 is connected to two sets of stirring paddles 4 that can move linearly on the electroplating tank body 1. The drive assembly 3 includes a fixed plate 31, a drive motor 32, a rotating block 33, a fisheye connecting rod 34, and a fixed rod 35. The fixed plate 31 is fixed to the outside of the electroplating tank body 1, and the drive motor 32 is fixed on the fixed plate 31. The output end of the drive motor 32 is connected to the rotating block 33. One end of the fisheye connecting rod 34 is hinged to the rotating block 33, and the other end is hinged to the fixed rod 35. The fixed rod 35 is fixedly connected to the two sets of stirring paddles 4. The center of the connection between the fisheye connecting rod 34 and the rotating block 33 is eccentrically set with the center of the output end of the drive motor 32, so that the fisheye connecting rod 34 can move linearly with the rotation of the rotating block 33, thereby driving the two sets of stirring paddles 4 to move linearly on the electroplating tank body 1.
[0038] Two sets of stirring paddles 4 are respectively set on both sides of the wafer fixture 2. Each stirring paddle 4 above the anode area 1011 is equipped with a blade 5. In this embodiment, the number of blades 5 is the same as that of the electroplating sub-tank. Specifically, the drive motor 32 is driven so that the fisheye connecting rod 34 can move linearly following the rotation of the rotating block 33, thereby driving the two sets of stirring paddles 4 to move linearly on the electroplating tank body 1, and then driving the blades 5 to move back and forth in the anode area 1011, and finally stirring the electroplating solution near the wafer fixture 2 to achieve the purpose of uniform electroplating solution and reducing the thickness of the interface layer on the wafer surface.
[0039] Furthermore, the blades 5 have a V-shaped structure on both sides, which effectively reduces the fluctuation of the electroplating solution caused by the left and right stirring of the blades 5.
[0040] Each anode region 1011 contains an anode 6, with the six positive terminals of six external DC power supplies individually connected to the anode 6, and the negative terminals of all six DC power supplies connected to the wafer fixture 2. In this embodiment, the anode can be either soluble or insoluble, and is made from a 3mm thick titanium plate, whose smooth surface effectively improves uniformity.
[0041] A shielding plate 8 is also provided in the anode region 1011 between the agitator 4 and the anode 6. The thickness of the shielding plate 8 is not less than 40mm, which effectively improves the uniformity of electroplating. In this embodiment, the shielding plate 8 does not need to be customized according to the shape and size of the wafer. A commonly used titanium mesh anode frame is sufficient to meet the uniformity requirements.
[0042] In summary, this embodiment, by setting multiple independent anode zones 1011 in the electroplating tank 1 and setting multiple corresponding clamping mechanisms on both sides of the fixture body, increases the number of wafers 9 that the fixture can hold at one time, realizing the electroplating of multiple wafers 9 at one time, improving the output and efficiency of electroplating, and reducing costs. Furthermore, a paddle 5 is set in each anode zone 1011 to stir the electroplating solution near the wafer 9 in each anode zone 1011, thereby achieving the purpose of uniform electroplating solution and reducing the thickness of the interface layer on the surface of the wafer 9, ensuring the uniformity of the coating thickness.
[0043] In addition, multiple conductive probes 24 are used to fix the wafer 9, which improves the fixing effect. By setting the transmission block 2221 and the step 2222, the second spring clip 222 can drive the first spring clip 221 and the third spring clip 223 to rotate synchronously relative to the fixture body 21, saving steps when picking up and putting down the wafer 9.
[0044] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.
[0045] The above-described embodiments are merely examples of implementation methods of the utility model. The scope of protection of this utility model is not limited to the above-described embodiments. For those skilled in the art, several modifications and improvements can be made without departing from the concept of this utility model, and these all fall within the scope of protection of this utility model.
Claims
1. A multi-wafer electroplating cell, characterized by: The system includes an electroplating tank body, a wafer jig, a drive assembly, a stirring paddle, paddle blades, and an anode. The wafer jig is located at the center of the electroplating tank body, dividing the tank body into two parts. Multiple electroplating sub-tanks are arranged along the length of the wafer jig within the electroplating tank body on both sides of the jig. Each sub-tank is divided into an anode area and an overflow area by a partition. The anode area is located close to the wafer jig. The output end of the drive assembly is connected to two sets of stirring paddles that can move linearly on the electroplating tank body. The two sets of stirring paddles are respectively located on both sides of the wafer jig. Each stirring paddle above the anode area is equipped with a blade. The drive assembly drives the blades to move within the anode area via the stirring paddles. An anode is provided in each anode area.
2. A multi-wafer electroplating cell as claimed in claim 1, wherein: The wafer fixture includes a fixture body and a clamping mechanism. Multiple clamping mechanisms are provided on both ends of the fixture body. The clamping mechanism includes a spring clip, which is connected to the fixture body by a torsion spring.
3. A multi-wafer electroplating cell as claimed in claim 2, wherein: The clamping mechanism also includes a conductive probe, through which the spring clip abuts against the wafer.
4. A multi-wafer electroplating cell as claimed in claim 3, wherein: The spring clip includes a first spring clip, a second spring clip, and a third spring clip arranged sequentially along the length of the clamp body. The free ends of the first spring clip, the second spring clip, and the third spring clip are all fixedly connected to conductive probes.
5. A multi-wafer electroplating cell as claimed in claim 4, wherein: The conductive probe includes a first conductive probe, a second conductive probe, and a third conductive probe, which are respectively fixedly connected to the top of the first spring clip, the second spring clip, and the third spring clip.
6. A multi-wafer electroplating cell as claimed in claim 1, wherein: The drive assembly includes a fixed plate, a drive motor, a rotating block, a fisheye connecting rod, and a fixed rod. The fixed plate is fixed to the outside of the electroplating tank body, and the drive motor is fixed to the fixed plate. The output end of the drive motor is connected to the rotating block. One end of the fisheye connecting rod is hinged to the rotating block, and the other end is hinged to the fixed rod. The fixed rod is fixedly connected to two sets of stirring paddles. The center of the connection between the fisheye connecting rod and the rotating block is eccentrically set to the center of the output end of the drive motor.
7. A multi-wafer electroplating cell as claimed in claim 1, wherein: The top of the partition has a wavy structure.
8. The multi-wafer electroplating cell of claim 1, wherein: A shielding plate is also provided in the anode zone between the agitator and the anode.
9. A multi-wafer electroplating tank according to claim 8, characterized in that: The thickness of the shielding plate shall not be less than 40mm.