Electroplating apparatus and electroplating method

Abstract

One embodiment of the present invention discloses an electroplating apparatus, including an electroplating tank, a fixture, a positioning cylinder, and an anode. The positioning cylinder is located in the electroplating tank, with one end open. The anode is located inside the positioning cylinder, and the positioning cylinder is in sealed contact with the anode. Only a first surface of the anode is in contact with the electroplating solution across its entire surface area. The first surface is parallel to and opposite to a substrate, with its center aligned with the center of the substrate. The size of the first surface is similar to the size of the effective electroplating area of ​​the substrate. This electroplating apparatus enables the electric field generated by the anode to be uniformly distributed on the substrate surface, thereby improving the uniformity of the electroplating height on the substrate surface. Another embodiment of the present invention also discloses an electroplating method using the above-described electroplating apparatus.

Description

[Technical Field]

[0001] This invention relates to the field of semiconductor equipment, and more particularly to an electroplating apparatus and an electroplating method. [Previous Technology]

[0002] In the electroplating process, the anode and the substrate are immersed in the electroplating solution. An electric field is generated on the surface of the anode, and under the action of the electric field, metal is gradually deposited on the surface of the substrate. As shown in Figure 1A, in existing electroplating equipment, the size of the surface of the anode 101 is larger than the size of the substrate 102, which causes the electric field line density at the edge of the substrate 102 to be greater than that at the center of the substrate 102. As shown in Figure 1B, the electroplating height at the edge of the substrate is significantly higher. As shown in Figure 2, the usual solution is to install an edge baffle 204 in the electroplating chamber. The edge baffle 204 is located between the anode 201 and the substrate 202, blocking the outer periphery of the anode 201 so that the size of the unblocked area at the center of the anode 201 is approximately the same as the size of the substrate 202. However, since an electric field is also generated at the outer periphery of the anode 201, the electric field will still bypass the edge baffle 204 and reach the substrate 202, causing the electroplating height at the edge of the substrate 202 to still be higher than that at the center of the substrate 202, resulting in uneven electroplating height on the surface of the substrate 202.

[0003] Furthermore, since the electric field is distributed throughout the electroplating solution, an electric field is generated on the anode surface that comes into contact with the electroplating solution. The surface that generates the electric field is called the effective surface, as shown in Figures 3A and 3B. Since the side surface of the anode is also an effective surface, it is difficult to control the uniformity of the generated electric field, resulting in uneven electroplating height on the substrate surface.

[0004] On the other hand, the metal block acts as the anode, replenishing the metal ions consumed in the electroplating solution during the electroplating process. As the process proceeds, the anode surface is continuously consumed, the anode thickness gradually decreases, and the distance from the anode surface to the substrate (i.e., the cathode) surface gradually increases. This change in distance will alter the electroplating deposition rate and increase the difficulty of process control, especially when the electroplated metal layer is very thin, requiring precise control of the electroplating process. [Summary of the Invention]

[0005] One object of the present invention is to provide an electroplating apparatus that makes the electric field generated by the anode uniformly distributed on the surface of the substrate, thereby improving the uniformity of the electroplating height on the substrate surface.

[0006] To achieve the above objective, one embodiment of the present invention provides an electroplating apparatus, comprising: an electroplating tank for containing an electroplating solution; a clamp for holding a substrate; a positioning cylinder located in the electroplating tank, one end of the positioning cylinder being open; and an anode located inside the positioning cylinder, the positioning cylinder being in sealed contact with the anode, wherein only a first surface of the anode is in contact with the electroplating solution in the entire surface area of ​​the anode, the first surface being parallel to and opposite the substrate, the center of the first surface being directly opposite the center of the substrate, and the size of the first surface being similar to the size of the effective electroplating area of ​​the substrate.

[0007] Another object of the present invention is to provide an electroplating apparatus that not only makes the electric field generated by the anode uniformly distributed on the substrate surface, thereby improving the uniformity of the electroplating height on the substrate surface, but also keeps the distance between the anode and the substrate constant, thereby improving the stability of the process results.

[0008] To achieve the above objective, one embodiment of the present invention provides an electroplating apparatus, comprising: an electroplating tank for containing an electroplating solution; a clamp for holding a substrate; a positioning cylinder located in the electroplating tank, one end of the positioning cylinder being open; and an anode located inside the positioning cylinder, the positioning cylinder being in sealed contact with the anode, wherein only a first surface of the anode is in contact with the electroplating solution in the entire surface area of ​​the anode, the first surface being parallel to and opposite the substrate, the center of the first surface being directly opposite the center of the substrate, and the size of the first surface being similar to the size of the effective electroplating area of ​​the substrate;

[0009] A drive device and a controller, wherein the drive device is connected to the anode and the controller respectively, the controller periodically calculates the change in distance between the first surface of the anode and the substrate, and controls the drive device to drive the anode to move toward the substrate so that the distance between the first surface of the anode and the substrate reaches a set value.

[0010] Another embodiment of the present invention provides an electroplating method, comprising: setting a positioning cylinder in an electroplating tank, placing an anode in the positioning cylinder, the inner wall of the positioning cylinder being in sealed contact with the anode, such that only the first surface of the anode is in contact with the electroplating solution in the surface area of ​​the anode, the first surface of the anode being parallel to and opposite to the substrate, and the center of the first surface of the anode being directly opposite the center of the substrate; installing a driving device in the electroplating tank, the driving device being connected to the anode, calculating or detecting the change in distance between the first surface of the anode and the substrate, and controlling the movement of the driving device to move the anode toward the substrate until the distance between the first surface of the anode and the substrate reaches a set value.

[0011] This invention improves the uniformity of the electric field distribution by making the cross-sectional size of the electric field generated by the anode similar to the size of the effective electroplating area of ​​the substrate during the electroplating process. This makes the electric field intensity near the effective electroplating area of ​​the substrate similar, thereby improving the uniformity of the electroplating height on the substrate surface.

Implementation Method

[0013] To explain in detail the technical content, structural features, objectives and effects of the present invention, the following will provide a detailed description in conjunction with embodiments and accompanying drawings.

[0014] Figure 1A shows a conventional electroplating apparatus in which an anode 101 and a substrate 102 are immersed in an electroplating solution 103, with the substrate 102 serving as the cathode. During electroplating, an electric field is generated on the upper surface of the anode 101. Since the size of the upper surface of the anode 101 is larger than the size of the substrate 102, the electric field lines near the edge of the substrate 102 are denser than those near the center of the substrate 102, resulting in a greater electric field strength near the edge of the substrate 102. Therefore, the electroplating height at the edge of the substrate 102 is higher than that in other areas. The electroplating result curve is shown in Figure 1B, indicating poor uniformity of the electroplating height on the substrate.

[0015] As shown in Figure 2, in an attempt to solve this problem, a common practice is to install an edge baffle 204 in the electroplating tank. The edge baffle 204 is annular and is positioned between the anode 201 and the substrate 202 to shield the outer periphery of the anode 201 and block the electric field generated on the outer periphery of the anode 201. However, since the surface of the anode 201 and the substrate 202 are filled with electroplating solution 203, the electric field generated on the outer periphery of the anode 201 can still bypass the edge baffle 204 and reach the substrate 202, causing the electroplating height near the edge of the substrate 202 to be higher than the electroplating height in other areas of the substrate 202.

[0016] In addition, as shown in Figures 3A and 3B, since the side surface of the anode 301 is also immersed in the electroplating solution 303, an electric field will also be generated on the side surface of the anode 301. Since it is difficult to control the intensity of the electric field near various parts of the substrate, it is difficult to control the electroplating height on the surface of the substrate 302.

[0017] In order to make the electric field intensity between the anode and the substrate uniformly distributed, the present invention has improved the design of the electroplating apparatus and method, as detailed in the following embodiments.

[0018] Example 1 As shown in Figure 4, this embodiment provides an electroplating apparatus, including an anode 401, a positioning cylinder 404, an ion exchange membrane 406, a diffusion plate 407, an electroplating tank 408, and a clamp 409. The electroplating tank 408 is used to contain the electroplating solution 403, the clamp 409 is used to hold a substrate 402, the anode 401 is located below the substrate 402, and the upper surface 410 of the anode 401 is parallel to and opposite to the substrate 402. The ion exchange membrane 406 is located above the anode 401 and is used to separate the anolyte and catholyte in the electroplating tank 408. The diffusion plate 407 is located between the ion exchange membrane 406 and the substrate 402, and the diffusion plate 407 has multiple small holes through which the electroplating solution 403 can pass. The positioning cylinder 404 is located in the electroplating tank 408. The top of the positioning cylinder 404 is open, and the bottom of the positioning cylinder 404 is connected to the inner wall of the electroplating tank 408. The anode 401 is located in the positioning cylinder 404, and the shape of the inner wall of the positioning cylinder 404 matches that of the anode 401. The center of the upper surface 410 of the anode 401 is directly opposite to the center of the substrate 402. The positioning cylinder 404 is in sealed contact with at least the upper part of the side surface of the anode 401, so that only the upper surface 410 of the anode 401 is in contact with the electroplating solution 403 in the surface area of ​​the anode 401. Therefore, the electric field generated by the anode 401 is entirely emitted from the upper surface 410. The anode 401 can be a columnar body. The size B of the upper surface 410 of the anode 401 is similar to the size A of the effective electroplating area of ​​the substrate 402. Therefore, the size of the cross-section of the electric field generated by the anode 401 is the same as (absolutely the same or approximately the same) as the size A of the effective electroplating area of ​​the substrate 402, as shown in Figure 5. This can improve the uniformity of the electric field distribution, make the electric field intensity at various points on the effective electroplating area of ​​the substrate 402 similar, and improve the uniformity of the electroplating height on the surface of the substrate 402.

[0019] Regarding the effective electroplating area of ​​substrate 402, this area refers to the area where metal is deposited. For example, when a circular substrate 402 with a diameter of 300 mm is held by a clamp 409, an annular area with a width of 1.5 mm at the edge of substrate 402 is wrapped by a lip seal on clamp 409. This annular area will not be deposited with metal, so the diameter of the effective electroplating area of ​​substrate 402 is 297 mm.

[0020] As shown in Figure 6, during the electroplating process, the anode 401 is gradually consumed. Since the upper surface 410 of the anode 401 is consumed uniformly, the shape of the upper surface 410 remains unchanged. Therefore, the size of the cross-section of the electric field generated by the anode 401 remains unchanged.

[0021] In this embodiment, the inner wall of the positioning cylinder 404 is provided with a sealing element 405. The sealing element 405 is in sealing contact with at least the top of the side surface of the anode 401, so that the electroplating solution 403 will not leak to the side surface of the anode 401 and cause the side surface of the anode 401 to be consumed. Since the upper surface 410 of the anode 401 gradually descends during the electroplating process, but a new anode is usually replaced before the anode 401 is completely consumed, the sealing element 405 has at least a certain height in the vertical direction. This height is sufficient to ensure that the edge of the upper surface 410 of the anode 401 is always in sealing contact with the positioning cylinder 404.

[0022] The material of the positioning cylinder 404 can be a metal that does not participate in the electrochemical reaction, a rigid insulating material, etc. The inner wall of the positioning cylinder 404 can be provided with a groove, and the sealing element 405 can be embedded in the groove.

[0023] Example 2 As shown in Figure 7, this embodiment provides an electroplating apparatus. The structure of the electroplating apparatus is basically the same as that of the electroplating apparatus in Example 1. The difference from Example 1 is that in the electroplating apparatus of this embodiment, the inner wall of the upper part of the positioning cylinder 704 is in sealed contact with the upper part of the anode 701, and there is a space 7014 between the inner wall of the lower part of the positioning cylinder 704 and the lower part of the anode 701. The electroplating liquid 703 will not enter the space 7014, and the space 7014 can be used to accommodate other components.

[0024] The rest of the structure is the same as in Example 1, and will not be repeated here.

[0025] Example 3 As shown in Figure 8, this embodiment provides an electroplating apparatus, including an anode 801, a positioning cylinder 804, an ion exchange membrane 806, a diffuser plate 807, an electroplating tank 808, a clamp 809, an anode support plate 8010, a driving device 8011, a sensor 8012, and a controller 8013. The electroplating tank 808 is used to contain the electroplating solution 803, the clamp 809 is used to hold the substrate 802, the anode 801 is located below the substrate 802, and the upper surface 810 of the anode 801 is parallel to and opposite to the substrate 802. The ion exchange membrane 806 is located above the anode 801 and is used to separate the anolyte and catholyte in the electroplating tank 808. The diffuser plate 807 is located between the ion exchange membrane 806 and the substrate 802, and has multiple small holes through which the electroplating solution 803 can pass. The anode 801 is located in the positioning cylinder 804. The top of the positioning cylinder 804 is open, and the bottom of the positioning cylinder 804 is connected to the inner wall of the electroplating tank 808. The shape of the inner wall of the positioning cylinder 804 matches the anode 801, and the center of the upper surface 810 of the anode 801 is directly opposite the center of the substrate 802.

[0026] The inner wall of the positioning cylinder 804 is provided with an O-ring seal 805. The O-ring seal 805 is in sealing contact with the top of the side wall of the anode 801, so that only the upper surface 810 of the anode 801 is in contact with the electroplating solution 803 in the surface area of ​​the anode 801. Therefore, the electric field generated by the anode 801 is entirely emitted from the upper surface 810. The anode 801 can be a columnar body. The size B of the upper surface 810 of the anode 801 is similar to the size A of the effective electroplating area of ​​the substrate 802. Therefore, the cross-sectional size of the electric field generated by the anode 801 is the same as (absolutely the same or approximately the same) as the size A of the effective electroplating area of ​​the substrate 802. This can improve the uniformity of the electric field distribution, make the electric field intensity at various points on the effective electroplating area of ​​the substrate 802 similar, and improve the uniformity of the electroplating height on the surface of the substrate 802.

[0027] Regarding the effective electroplating area of ​​substrate 802, this area refers to the area where metal is deposited. For example, when a circular substrate 802 with a diameter of 200 mm is held by a clamp 809, an annular area with a width of 1 mm at the edge of substrate 802 is wrapped by a lip seal on clamp 809. This annular area will not be deposited with metal, so the diameter of the effective electroplating area of ​​substrate 802 is 198 mm.

[0028] The sensor 8012 is fixed on the outer wall of the electroplating tank 808. The sensor 8012 can detect whether the upper surface 810 of the anode 801 is at a set height, so that the distance between the upper surface 810 of the anode 801 and the substrate 802 is maintained at a set value. Specifically, the sensor 8012 is flush with the upper surface 810 of the anode 801, and the upper surface 810 of the anode 801 is detected by the sensor 8012.

[0029] To prevent the electroplating solution overflowing from the electroplating tank 808 from contaminating or damaging the sensor 8012, a cover can be installed above the sensor 8012.

[0030] The anode 801 is composed of two or more small anodes in the horizontal direction. The bottom of the anode 801 is provided with an anode support plate 8010. The drive device 8011 is located below the anode support plate 8010. The output shaft of the drive device 8011 is connected to the anode support plate 8010.

[0031] The controller 8013 is connected to the sensor 8012 and the drive device 8011 respectively.

[0032] During the electroplating process, the anode 801 is gradually consumed. Since the upper surface 810 of the anode 801 can be considered to be consumed uniformly, the shape of the upper surface 810 of the anode 801 remains unchanged, and therefore the size of the cross-section of the electric field generated by the anode 801 remains unchanged. When the height of the upper surface 810 of the anode 801 decreases, it can no longer be detected by the sensor 8012. At this time, the sensor 8012 sends a first signal to the controller 8013. After receiving the first signal, the controller 8013 sends a command to the drive device 8011, causing the output shaft of the drive device 8011 to move and slowly lift the anode 801 upward until the sensor 8012 detects the upper surface 810 of the anode 801 again. At this time, the sensor 8012 sends a second signal to the controller 8013. After receiving the second signal, the controller 8013 sends a command to the drive device 8011, and the drive device 8011 stops moving. This ensures that the upper surface 810 of the anode 801 is always kept at a set height, and the distance between the upper surface 810 of the anode 801 and the substrate 802 remains constant, making the process results more stable and not changing with anode consumption.

[0033] Alternatively, the height change of the upper surface 810 of the anode 801 can be inferred from the anode metal consumption calculated periodically by the controller, thereby controlling the drive device 8011 to lift the upper surface 810 of the anode 801 to the initial position. The anode metal consumption is related to factors such as electroplating current, energizing time, and electroplating efficiency. For specific calculation methods, please refer to the Japanese Patent Publication No. JP1983113399A. The drive device 8011 should move as little as possible each time to prevent the upper surface 810 of the anode 801 from detaching from the O-ring seal 805, which could lead to seal failure.

[0034] As shown in Figure 9, after the electroplating process has been carried out for a period of time, the thickness of the anode 801 decreases, but the upper surface of the anode 801 remains at a constant height.

[0035] In this embodiment, the sensor 8012 is an infrared sensor, including a transmitting sensor and a receiving sensor. A viewing window is provided on both sides of the electroplating tank 808. If the infrared light emitted by the transmitting sensor is sensed by the receiving sensor on the other side through the viewing window, the upper surface 810 of the anode 801 is below the set height. At this time, the anode 801 needs to be raised so that the upper surface 810 of the anode 801 reaches the set height.

[0036] In other embodiments, the sensor 8012 may also be a tactile sensor with an elastic contact. The contact of the sensor 8012 is mounted on the top of the positioning cylinder 804. When the anode 801 is below the set height, the contact does not contact the upper surface 8109 of the anode 801. At this time, the anode 801 needs to be raised so that the upper surface 8109 of the anode 801 contacts the contact.

[0037] The number of O-rings 805 can be more than two.

[0038] Example 4 As shown in Figure 10, this embodiment provides an electroplating apparatus, including an anode 901, a positioning cylinder 904, an ion exchange membrane 906, a diffuser plate 907, an electroplating tank 908, a clamp 909, an anode support plate 9010, a drive device 9011, a sensor 9012, and a controller 9013. The electroplating tank 908 is used to contain the electroplating solution 903, the clamp 909 is used to hold the substrate 902, the anode 901 is located below the substrate 902, and the upper surface 910 of the anode 901 is parallel to and opposite to the substrate 902. The ion exchange membrane 906 is located above the anode 901 and is used to separate the anolyte and catholyte in the electroplating tank 908. The diffuser plate 907 is located between the ion exchange membrane 906 and the substrate 902, and has multiple small holes through which the electroplating solution 903 can pass. The anode 901 is located in the positioning cylinder 904. The top of the positioning cylinder 904 is open, and the bottom of the positioning cylinder 904 is connected to the inner wall of the electroplating tank 908. The shape of the inner wall of the positioning cylinder 904 matches the anode 901, and the center of the upper surface 910 of the anode 901 is directly opposite the center of the substrate 902.

[0039] The inner wall of the positioning cylinder 904 is provided with an upper sealing ring 9051, a lower sealing ring 9052, and an annular groove 9014. The positioning cylinder 904 is provided with a water inlet channel 9015 and a water outlet channel 9016. The upper sealing ring 9051 is in sealing contact with the top of the side wall of the anode 901, so that only the upper surface 910 of the anode 901 is in contact with the electroplating solution 903 in the surface area of ​​the anode 901. Therefore, the electric field generated by the anode 901 is entirely emitted from the upper surface 910. The anode 901 can be a columnar body. The size B of the upper surface 910 of the anode 901 is similar to the size A of the effective electroplating area of ​​the substrate 902. Therefore, the cross-sectional size of the electric field generated by the anode 901 is the same as (absolutely the same or approximately the same) as the size A of the effective electroplating area of ​​the substrate 902. This can improve the uniformity of the electric field distribution, make the electric field intensity at various points on the effective electroplating area of ​​the substrate 902 similar, and improve the uniformity of the electroplating height on the surface of the substrate 902.

[0040] As shown in Figure 11, the lower sealing ring 9052 is located below the upper sealing ring 9051, and the annular groove 9014 is located between the upper sealing ring 9051 and the lower sealing ring 9052. The top of the water inlet channel 9015 communicates with the annular groove 9014, and the bottom of the water inlet channel 9015 is connected to the water inlet pump 9017, which is used to deliver liquid from the outside into the annular groove 9014. The top of the water outlet channel 9016 communicates with the annular groove 9014, and the bottom of the water outlet channel 9016 is connected to the water outlet pump 9018, which is used to discharge the liquid in the annular groove 9014 to the outside. The water inlet pump 9017 and the water outlet pump 9018 operate continuously, keeping the liquid, such as water, in the annular groove 9014 in a flowing state. Fresh liquid enters the annular groove 9014 through the water inlet channel 9015 and then flows out through the water outlet channel 9016. When the upper sealing ring 9051 leaks, the electroplating solution 903 seeps downwards into the annular groove 9014, where it is diluted by the liquid. The diluted electroplating solution 903 flows out through the outlet channel 9016, preventing it from accumulating in the annular groove 9014 and corroding the sidewall of the anode 901. The lower sealing ring 9052 prevents liquid from seeping downwards and contaminating the drive unit 9011. The inlet channel 9015 and the outlet channel 9016 are preferably located at the radial ends of the annular groove 9014 to ensure sufficient liquid flow within the groove and adequate dilution of the electroplating solution 903.

[0041] The sensor 9012 is fixed to the outer wall of the electroplating tank 908. The sensor 9012 can detect whether the upper surface 910 of the anode 901 is at a set height, so that the distance between the upper surface 910 of the anode 901 and the substrate 902 is maintained at a set value. Specifically, the sensor 9012 is flush with the upper surface 910 of the anode 901, and the upper surface 910 of the anode 901 is detected by the sensor 9012.

[0042] To prevent the electroplating solution overflowing from the electroplating tank 908 from contaminating or damaging the sensor 9012, a cover may be installed above the sensor 9012.

[0043] The anode 901 is composed of two or more small anodes in the horizontal direction. The bottom of the anode 901 is provided with an anode support plate 9010. The drive device 9011 is located below the anode support plate 9010. The output shaft of the drive device 9011 is connected to the anode support plate 9010.

[0044] The controller 9013 is connected to the sensor 9012 and the drive device 9011 respectively.

[0045] During the electroplating process, the anode 901 is gradually consumed. Since the upper surface 910 of the anode 901 can be considered to be consumed uniformly, the shape of the upper surface 910 of the anode 901 remains unchanged, and therefore the size of the cross-section of the electric field generated by the anode 901 remains unchanged. When the height of the upper surface 910 of the anode 901 decreases, it can no longer be detected by the sensor 9012. At this time, the sensor 9012 sends a first signal to the controller 9013. After receiving the first signal, the controller 9013 sends a command to the drive device 9011, causing the output shaft of the drive device 9011 to move and slowly lift the anode 901 upward until the sensor 9012 detects the upper surface 910 of the anode 901 again. At this time, the sensor 9012 sends a second signal to the controller 9013. After receiving the second signal, the controller 9013 sends a command to the drive device 9011, and the drive device 9011 stops operating. This ensures that the upper surface 910 of the anode 901 is always kept at the set height, and the distance between the upper surface 910 of the anode 901 and the substrate 902 is constant, making the process results more stable and not changing with anode consumption.

[0046] The height change value of the upper surface 910 of the anode 901 can also be inferred based on the anode metal consumption calculated periodically by the controller, thereby controlling the drive device 9011 to lift the upper surface 910 of the anode 901 to the initial position.

[0047] In this embodiment, the sensor 9012 is an infrared sensor, including a transmitting sensor and a receiving sensor. A viewing window is provided on both sides of the electroplating tank 908. If the infrared light emitted by the transmitting sensor is sensed by the receiving sensor on the other side through the viewing window, the upper surface 910 of the anode 901 is below the set height. At this time, the anode 901 needs to be raised so that the upper surface 910 of the anode 901 reaches the set height.

[0048] Example 5 As shown in Figure 12, this embodiment provides an electroplating apparatus, including an anode 1001, a positioning cylinder 1004, an electroplating tank 1008, and a clamp 1009. The electroplating tank 1008 is used to contain an electroplating solution 1003, and the clamp 1009 is used to hold a substrate 1002. Both the anode 1001 and the substrate 1002 are vertically immersed in the electroplating solution 1003, and the right surface 1010 of the anode 1001 is parallel to and opposite to the substrate 1002. The positioning cylinder 1004 is located in the electroplating tank 1008, and its bottom is connected to the inner wall of the electroplating tank 1008. The anode 1001 is located in the positioning cylinder 1004, which has an open right end. The shape of the inner wall of the positioning cylinder 1004 matches that of the anode 1001, and the center of the right surface 1010 of the anode 1001 is directly opposite to the center of the substrate 1002. A sealing element 1005 is provided at the contact point between the positioning cylinder 1004 and the anode 1001, so that only the right surface 1010 of the anode 1001 contacts the electroplating solution 1003 in the surface area of ​​the anode 1001, and the electric field generated by the anode 1001 is entirely emitted from the right surface 1010. The anode 1001 can be a columnar body, and the size of the right surface 1010 of the anode 1001 is similar to the size of the effective electroplating area of ​​the substrate 1002. Therefore, the cross-sectional size of the electric field generated by the anode 1001 is similar to the size of the effective electroplating area of ​​the substrate 1002, which improves the uniformity of the electric field distribution and makes the electric field intensity at various points on the effective electroplating area of ​​the substrate 1002 similar, thereby improving the uniformity of the electroplating height on the surface of the substrate 1002.

[0049] Example 6 As shown in Figure 13, this example provides an electroplating apparatus, which includes all the structures of the electroplating apparatus described in Example 1, and will not be repeated here. In addition, the bottom of the electroplating tank 1108 is provided with a gas inlet 1112, which is used to introduce air or oxygen into the electroplating solution, so that the metal ions in the electroplating solution are fully oxidized and transformed into more stable metal ions under the action of oxygen.

[0050] Example 7 This embodiment provides an electroplating method, including: setting a positioning cylinder in an electroplating tank, placing an anode in the positioning cylinder, the inner wall of the positioning cylinder being in sealed contact with the anode, so that only the first surface of the anode is in contact with the electroplating solution in the surface area of ​​the anode, the first surface of the anode is parallel to and opposite to the substrate, and the size of the first surface of the anode is similar to the size of the effective electroplating area of ​​the substrate, the center of the first surface of the anode is directly opposite the center of the substrate; setting the distance between the first surface of the anode and the substrate; calculating the change in the distance between the first surface of the anode and the substrate, and driving the anode to move towards the substrate until the distance between the first surface of the anode and the substrate reaches the set value.

[0051] Example 8 This embodiment provides an electroplating method, including: setting a positioning cylinder in the electroplating tank of an electroplating apparatus, placing an anode in the positioning cylinder, the inner wall of the positioning cylinder being in sealed contact with the anode, so that only the first surface of the anode is in contact with the electroplating solution in the surface area of ​​the anode, the first surface of the anode being parallel to and opposite to the substrate, and the size of the first surface of the anode being similar to the size of the effective electroplating area of ​​the substrate, the center of the first surface of the anode being directly opposite the center of the substrate; setting the distance between the first surface of the anode and the substrate; detecting the position of the first surface of the anode by a sensor and sending a signal to a controller; when the distance between the first surface of the anode and the substrate exceeds the set value, the sensor sends a first signal to the controller, and after receiving the first signal, the controller sends a command to the driving device, the driving device drives the anode to move towards the substrate until the distance between the first surface of the anode and the substrate is equal to the set value, at which point the sensor sends a second signal to the controller, and after receiving the second signal, the controller sends a command to the driving device, the driving device stops operating.

[0052] In order to make the metal ions in the electroplating solution more stable, a gas inlet is opened on the electroplating tank to introduce air or oxygen into the electroplating solution. Under the action of oxygen, the metal ions are fully oxidized and transformed into more stable metal ions.

[0053] In summary, the present invention has specifically and thoroughly disclosed the relevant technology through the above embodiments and related drawings, enabling those skilled in the art to implement it accordingly. The above embodiments are merely illustrative of the present invention and not intended to limit it. The scope of the present invention should be defined by the scope of the patent applications. Any changes in the number of elements or substitutions of equivalent elements described herein should still fall within the scope of the present invention. [Simplified Explanation of the Diagram]

[0012] Figure 1A illustrates a schematic diagram of the electric field generated by the anode in a conventional electroplating apparatus. Figure 1B illustrates the electroplating result curve of the electroplating apparatus in Figure 1A. Figure 2 illustrates a schematic diagram of the electric field generated by the anode in an electroplating apparatus equipped with an edge baffle. Figure 3A illustrates a schematic diagram of the electric field generated by the anode in a conventional electroplating apparatus, wherein the size of the anode is larger than the size of the substrate, and electric fields are generated on both the side and top surfaces of the anode. Figure 3B illustrates a schematic diagram of the electric field generated by the anode in a conventional electroplating apparatus, wherein the size of the anode is smaller than the size of the substrate, and electric fields are generated on both the side and top surfaces of the anode. Figure 4 illustrates a cross-sectional schematic diagram of the electroplating apparatus in Embodiment 1 of the present invention. Figure 5 illustrates a schematic diagram of the electric field generated by the electroplating apparatus in Embodiment 1 of the present invention. Figure 6 illustrates a cross-sectional schematic diagram of the electroplating apparatus in Embodiment 1 of the present invention after operating for a period of time. Figure 7 illustrates a cross-sectional schematic diagram of the electroplating apparatus in Embodiment 2 of the present invention. Figure 8 illustrates a cross-sectional schematic diagram of the electroplating apparatus in Embodiment 3 of the present invention. Figure 9 illustrates a cross-sectional schematic diagram of the electroplating apparatus in Embodiment 3 of the present invention after operating for a period of time. Figure 10 illustrates a cross-sectional view of the electroplating apparatus in Embodiment 4 of the present invention. Figure 11 illustrates a partially enlarged view of Figure 10. Figure 12 illustrates a cross-sectional view of the electroplating apparatus in Embodiment 5 of the present invention. Figure 13 illustrates a cross-sectional view of the electroplating apparatus in Embodiment 6 of the present invention.

Claims

1. An electroplating apparatus, comprising: Electroplating tank, used to hold electroplating solution; A clamp used to hold a substrate; A positioning cylinder is located in an electroplating tank, with one end of the positioning cylinder open. The anode is located inside the positioning cylinder, and the positioning cylinder is in sealed contact with the anode. In the entire surface area of ​​the anode, only the first surface is in contact with the electroplating solution. The first surface is parallel to the substrate, and the center of the first surface is directly opposite the center of the substrate. The size of the first surface is similar to the size of the effective electroplating area of ​​the substrate. The positioning cylinder is in sealed contact with the second surface of the anode, and the second surface is perpendicular to the first surface.

2. The electroplating apparatus according to claim 1, wherein, The positioning cylinder is vertically arranged, and the inner wall of the positioning cylinder is provided with at least one ring of sealing elements. The sealing elements are in sealing contact with at least the edge of the first surface, and the sealing elements have a certain height in the vertical direction.

3. The electroplating apparatus according to claim 1 further includes a drive device and a controller, the drive device being connected to the anode and the controller respectively, the controller periodically calculating the change in distance between the first surface of the anode and the substrate, and controlling the drive device to drive the anode to move toward the substrate, so that the distance between the first surface of the anode and the substrate reaches a set value.

4. The electroplating apparatus according to claim 3, wherein, The anode is set vertically, and the anode is composed of two or more small anodes in the horizontal direction. The bottom of the anode is provided with an anode support plate, and the driving device is located below the anode support plate. The output shaft of the driving device is connected to the anode support plate.

5. The electroplating apparatus according to claim 1, wherein, The electroplating tank is equipped with a gas inlet for introducing air or oxygen into the electroplating solution.

6. The electroplating apparatus according to claim 1 further includes a driving device, a sensor, and a controller. The driving device is connected to the anode and the controller respectively. The sensor is connected to the controller and is disposed on the electroplating tank. The sensor detects the position of the first surface of the anode and sends a first signal or a second signal to the controller according to the detection result. The controller controls the driving device according to the received first signal or second signal. The driving device drives the anode to move toward the substrate until the distance between the first surface of the anode and the substrate reaches a set value.

7. The electroplating apparatus according to claim 6, wherein, The sensor is an infrared sensor, including a transmitting sensor and a receiving sensor. The electroplating tank is provided with two windows, and the infrared light emitted by the transmitting sensor is received by the receiving sensor through the windows.

8. The electroplating apparatus according to claim 6, wherein, The sensor is a tactile sensor with an elastic contact. The contact of the tactile sensor is mounted on the positioning cylinder. When the distance between the first surface of the anode and the substrate is greater than a set value, the first surface of the anode does not contact the contact. At this time, the driving device drives the anode to move towards the substrate so that the first surface of the anode contacts the contact.

9. The electroplating apparatus according to claim 6, wherein, The inner wall of the positioning cylinder is provided with at least one O-ring, and at least one O-ring is in sealing contact with the edge of the first surface.

10. The electroplating apparatus according to claim 6, wherein, The positioning cylinder is vertically arranged, and its inner wall is provided with an upper sealing ring, a lower sealing ring, and an annular groove. The positioning cylinder is provided with a water inlet channel and a water outlet channel. The upper sealing ring is in sealing contact with the edge of the first surface, the lower sealing ring is located below the upper sealing ring, and the annular groove is located between the upper and lower sealing rings. The top of the water inlet channel is connected to the annular groove, and the bottom of the water inlet channel is connected to a water inlet pump. The water inlet pump is used to deliver liquid from the outside into the annular groove. The top of the water outlet channel is connected to the annular groove, and the bottom of the water outlet channel is connected to a water outlet pump. The water outlet pump is used to discharge the liquid in the annular groove to the outside.

11. An electroplating method, comprising: A positioning cylinder is set in the electroplating tank, and the anode is placed in the positioning cylinder. The inner wall of the positioning cylinder is in sealed contact with the anode, so that only the first surface of the anode is in contact with the electroplating solution in the surface area of ​​the anode. The first surface of the anode is parallel to the substrate, and the center of the first surface of the anode is directly opposite the center of the substrate. And a drive device is installed in the electroplating tank. The drive device is connected to the anode, calculates or detects the change in distance between the first surface of the anode and the substrate, and controls the movement of the drive device to move the anode toward the substrate until the distance between the first surface of the anode and the substrate reaches the set value.

12. The electroplating method according to claim 11 further includes introducing air or oxygen into the electroplating solution.

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