Electrolytic plating apparatus and electrolytic plating method

Abstract

In one embodiment of the present invention, an electrolytic plating apparatus is disclosed. The electrolytic plating apparatus includes an electrolytic plating tank, a clamp, a positioning cylinder, and an anode. In the electrolytic plating apparatus, the positioning cylinder is located in the electrolytic plating tank, and one end of the positioning cylinder is open. The anode is located inside the positioning cylinder, and the positioning cylinder is in sealing contact with the anode. Furthermore, of the total surface area of ​​the anode, only a first surface is in contact with the electrolytic plating solution, the first surface faces the substrate in parallel, the center is aligned with the center of the substrate, and the size of the first surface is similar to the size of the effective electrolytic plating area of ​​the substrate. The electrolytic plating apparatus allows the electric field generated by the anode to be uniformly distributed on the surface of the substrate, thereby improving the uniformity of the electrolytic plating height on the surface of the substrate. Furthermore, in one embodiment of the present invention, an electrolytic plating method using the electrolytic plating apparatus is disclosed.

Description

Technical Field

[0004] , , ,

[0001] The present invention generally relates to the field of semiconductor devices, and more particularly to an electroplating apparatus and an electroplating method.

Background Art

[0002] In an electroplating process, an anode and a substrate are immersed in an electroplating solution, and an electric field is generated on the surface of the anode. Under the action of the electric field, metal gradually deposits on the surface of the substrate. As shown in FIG. 1A, in an existing electroplating apparatus, the size of the surface of the anode 101 is larger than the size of the substrate 102. Therefore, the electric line density at the edge of the substrate 102 is larger than the electric line density at the center of the substrate 102. Also, as shown in FIG. 1B, the electroplating at the edge of the substrate is significantly higher. As shown in FIG. 2, a general solution is to install an edge baffle 204 in the electroplating chamber. By disposing the edge baffle 204 between the anode 201 and the substrate 202 to cover the outer periphery of the anode 201, the size of the uncovered area at the center of the anode 201 is made substantially the same as the size of the substrate 202. However, since an electric field is also generated on the outer periphery of the anode 201, there is still a possibility that the electric field bypasses the edge baffle 204 and reaches the substrate 202. As a result, the electroplating height at the edge of the substrate 202 remains higher than the electroplating height at the center of the substrate 202, and the electroplating height on the surface of the substrate 202 becomes non-uniform.

[0003] Also, since the electric field is distributed everywhere in the electroplating solution, an electric field is generated on the surface of the anode in contact with the electroplating solution. Here, the surface where the electric field is generated is called an effective surface. As shown in FIGS. 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. As a result, the electroplating height on the surface of the substrate becomes non-uniform.

[0004] Meanwhile, the metal block functions as the anode, replenishing the metal ions consumed in the electroplating solution during the electroplating process. As the process progresses, the anode surface continues to wear down, its thickness gradually decreasing, and the distance from the anode surface to the substrate (i.e., the cathode) surface gradually increasing. As this distance changes, the deposition rate of the electroplating changes, making it more difficult to control the process. In particular, when the metal layer produced by electroplating is very thin, precise control of the electroplating process is necessary. [Overview of the Initiative]

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

[0006] To achieve the above-mentioned objective, one embodiment of the present invention provides an electrolytic plating apparatus. This electrolytic plating apparatus is An electrolytic plating tank configured to hold an electrolytic plating solution, A clamp configured to hold the circuit board, A positioning cylinder located inside the electrolytic plating tank, with one end open, The anode is located inside the positioning cylinder and is in sealed contact with the positioning cylinder, wherein only the first surface of its entire surface area is in contact with the electroplating solution, the first surface is parallel to the substrate, the center of the first surface is aligned with the center of the substrate, and the size of the first surface is the same as the size of the effective electroplating area of ​​the substrate.

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

[0008] To achieve the above-mentioned objective, one embodiment of the present invention provides an electrolytic plating apparatus. This electrolytic plating apparatus is An electrolytic plating tank configured to hold an electrolytic plating solution, A clamp configured to hold the circuit board, A positioning cylinder located inside the electrolytic plating tank, with one end open, An anode located inside a positioning cylinder and in sealed contact with the positioning cylinder, wherein only the first surface of the anode, which is parallel to the substrate, has its center aligned with the center of the substrate, and whose size is the same as the size of the effective electroplating area of ​​the substrate, is in contact with the electroplating solution. The system comprises a drive unit connected to the anode and a controller, respectively, and a controller. The controller periodically calculates the change in distance between the first surface of the anode and the substrate and controls the drive unit. The drive unit drives the anode, moving it toward the substrate, and brings the distance between the first surface of the anode and the substrate to a set value.

[0009] Another embodiment of the present invention provides an electroplating method. This electroplating method includes the steps of: installing a positioning cylinder in an electroplating bath, and positioning an anode inside the positioning cylinder so as to be in sealed contact with the inner wall of the positioning cylinder, wherein only the first surface of the anode is in contact with the electroplating solution in the surface region 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 aligned with the center of the substrate; The process includes: installing a drive device in an electroplating bath so as to be in contact with the anode; calculating or detecting the distance between the first surface of the anode and the substrate; and controlling the operation 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 a set value.

[0010] During the electroplating process, the present invention improves the uniformity of the electric field distribution by making the cross-sectional size of the electric field generated by the anode the same as the size of the effective electroplating region of the substrate. As a result, the electric field strength at each location near the effective electroplating region of the substrate is brought closer together, improving the uniformity of the electroplating height on the surface of the substrate. [Brief explanation of the drawing]

[0011] Figure 1A is a schematic diagram showing the electric field generated by the anode of an existing electrolytic plating apparatus. Figure 1B shows the curve of the electrolytic plating result obtained using the electrolytic plating apparatus in Figure 1A. Figure 2 is a schematic diagram showing the electric field generated by the anode in an electroplating apparatus equipped with edge baffles. Figure 3A is a schematic diagram showing the electric field generated by the anode of an existing electroplating apparatus. The diagram shows that the size of the anode is larger than the size of the substrate, and that an electric field is generated on both the side and top surfaces of the anode. Figure 3B is a schematic diagram showing the electric field generated by the anode of an existing electroplating apparatus. The diagram shows that the size of the anode is smaller than the size of the substrate, and that the electric field is generated on both the side and top surfaces of the anode. Figure 4 is a schematic diagram showing the cross-sectional structure of an electrolytic plating apparatus in the first embodiment of the present invention. Figure 5 is a schematic diagram showing the electric field generated by the electrolytic plating apparatus in the first embodiment of the present invention. Figure 6 is a schematic diagram showing the cross-sectional structure of the electrolytic plating apparatus after it has been operated for a certain period of time according to the first embodiment of the present invention. Figure 7 is a schematic diagram showing the cross-sectional structure of an electrolytic plating apparatus in a second embodiment of the present invention. Figure 8 is a schematic diagram showing the cross-sectional structure of an electrolytic plating apparatus in a third embodiment of the present invention. Figure 9 is a schematic diagram showing the cross-sectional structure of the electrolytic plating apparatus after it has been operated for a certain period of time according to the third embodiment of the present invention. Figure 10 is a schematic diagram showing the cross-sectional structure of an electrolytic plating apparatus in the fourth embodiment of the present invention. Figure 11 is a magnified view of a portion of Figure 10. Figure 12 is a schematic diagram showing the cross-sectional structure of an electrolytic plating apparatus in a fifth embodiment of the present invention. Figure 13 is a schematic diagram showing the cross-sectional structure of an electrolytic plating apparatus in the sixth embodiment of the present invention. [Modes for carrying out the invention]

[0012] To explain the technical content, structural features, purpose, and effects of the present invention in detail, embodiments and drawings will be described below in detail.

[0013] Figure 1A shows an existing electroplating apparatus in which the anode 101 and substrate 102 are immersed in electroplating solution 103, with the substrate 102 functioning 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 edges of the substrate 102 are denser than those near the center of the substrate 102. Also, because the electric field strength is greater near the edges of the substrate 102, the electroplating height at the edges of the substrate 102 is higher than the electroplating height in other areas. According to the electroplating result curve shown in Figure 1B, the uniformity of the electroplating height on the substrate is low.

[0014] As shown in Figure 2, to attempt to solve this problem, an edge baffle 204 is usually installed in the electroplating tank. The edge baffle 204 is annular and is positioned between the anode 201 and the substrate 202, shielding the outer circumference of the anode 201 from light in order to block the electric field generated on the outer circumference of the anode 201. However, because the electroplating solution 203 fills the space between the surface of the anode 201 and the substrate 202, the electric field generated around the anode 201 still bypasses the edge baffle 204 and reaches the substrate 202. Therefore, the electroplating height near the edge of the substrate 202 is still higher than the electroplating height in the rest of the substrate 202.

[0015] Furthermore, as shown in Figures 3A and 3B, since the sides of the anode 301 are also immersed in the electroplating solution 303, an electric field is generated on the sides of the anode 301 as well. Because it is difficult to control the electric field strength at various locations near the substrate, it is also difficult to control the electroplating height on the surface of the substrate 302.

[0016] In order to uniformly distribute the electric field strength between the anode and the substrate, the present invention improves the design of the electroplating apparatus and electroplating method as shown in the following embodiments.

[0017] (First Embodiment) As shown in Figure 4, this embodiment provides an electroplating apparatus comprising an anode 401, a positioning cylinder 404, an ion film 406, a diffuser plate 407, an electroplating tank 408, and a clamp 409. The electroplating tank 408 is used to hold the electroplating solution 403. The clamp 409 is used to hold the substrate 402. The anode 401 is located below the substrate 402, and the upper surface 410 of the anode 401 faces the substrate 402 parallel to it. The ion film 406 is located above the anode 401 and is used to separate the electroplating solution on the anode side from the electroplating solution on the cathode side in the electroplating tank 408. The diffuser plate 407 is located between the ion film 406 and the substrate 402. The diffuser plate 407 has a plurality of small holes for the electroplating solution 403 to pass through. The positioning cylinder 404 is located inside the electroplating tank 408, with its top open and its bottom connected to the inner wall of the electroplating tank 408. The anode 401 is located inside the positioning cylinder 404. The shape of the inner wall of the positioning cylinder 404 matches that of the anode 401, and the center of the upper surface 410 of the anode 401 is aligned with 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 such that only the upper surface 410 of the anode 401's surface area is in contact with the electroplating solution 403. Therefore, the electric field generated by the anode 401 is completely discharged from the upper surface 410. The anode 401 may be cylindrical. Since the size B of the upper surface 410 of the anode 401 is the same as the size A of the effective electroplating region of the substrate 402, the size of the cross-section of the electric field generated by the anode 401 is the same as (exactly the same or nearly the same as) the size A of the effective electroplating region of the substrate 402. Therefore, as shown in Figure 5, the uniformity of the electric field distribution can be improved, and the electric field strength at each location in the effective electroplating region of the substrate 402 can be made closer to each other. In addition, this can improve the uniformity of the electroplating height on the surface of the substrate 402.

[0018] The effective electrolytic plating area of the substrate 402 is the area where metal is deposited. For example, when a circular substrate 402 with a diameter of 300 mm is held by the clamp 409, there is an annular area with a width of 1.5 mm wrapped by the lip seal of the clamp 409 at the edge of the substrate 402. Since no metal is deposited in this annular area, the diameter of the effective electrolytic plating area of the substrate 402 is 297 mm.

[0019] As shown in FIG. 6, during the electrolytic plating process, the anode 401 gradually wears out. Since the upper surface 410 of the anode 401 wears out 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 also does not change.

[0020] In this embodiment, a ring of the seal member 405 is provided on the inner wall of the positioning cylinder 404. Since the seal member 405 is in airtight contact with at least the upper part of the side surface of the anode 401, the electrolytic plating solution 403 does not leak out to the side surface of the anode 401, and the side surface of the anode 401 does not wear out. During the electrolytic plating process, the upper surface 410 of the anode goes on decreasing gradually. Therefore, usually, before the anode 401 is completely worn out, it is replaced with a new anode, but the seal member 405 has at least a certain height in the vertical direction. This height can be set to ensure that the edge of the upper surface 410 of the anode 401 is always in airtight contact with the positioning cylinder 404.

[0021] The material of the positioning cylinder 404 can be a metal that does not participate in the electrochemical reaction, a highly rigid insulating material, etc. Also, a groove can be provided on the inner wall of the positioning cylinder 404, and the seal member 405 can be embedded in the groove.

[0022] (Second Embodiment) As shown in Figure 7, this embodiment provides an electroplating apparatus. The structure of this electroplating apparatus is essentially the same as that of the electroplating apparatus of the first embodiment. The difference from the first embodiment is that in the electroplating apparatus of this embodiment, the upper inner wall 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 lower inner wall of the positioning cylinder 704 and the lower part of the anode 701, and the electroplating solution 703 does not enter the space 7014. This space 7014 can be used to accommodate other components.

[0023] The remaining configuration is the same as in the first embodiment, so we will omit its explanation.

[0024] (Third embodiment) As shown in Figure 8, this embodiment provides an electroplating apparatus comprising an anode 801, a positioning cylinder 804, an ion film 806, a diffuser plate 807, an electroplating tank 808, a clamp 809, an anode support plate 8010, a drive unit 8011, a sensor 8012, and a controller 8013. The electroplating tank 808 is used to hold 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 faces the substrate 802 parallel to it. The ion film 806 is located above the anode 801 and is used to separate the electroplating solution on the anode side from the electroplating solution on the cathode side in the electroplating tank 808. The diffuser plate 807 is located between the ion film 806 and the substrate 802. The diffuser plate 807 also has a plurality of small holes for the electroplating solution 803 to pass through. The anode 801 is located inside 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 that of the anode 801, and the center of the top surface 810 of the anode 801 is aligned with the center of the substrate 802.

[0025] An O-shaped seal ring 805 is provided on the inner wall of the positioning cylinder 804. The O-shaped seal ring 805 is in airtight contact with the upper part of the side wall of the anode 801 such that only the upper surface 810 of the surface area of ​​the anode 801 is in contact with the electroplating solution 803. As a result, the electric field generated by the anode 801 is completely discharged from the upper surface 810. The anode 801 may be cylindrical. Since the size B of the upper surface 810 of the anode 801 is the same as the size A of the effective electroplating area of ​​the substrate 802, the size of the cross-section of the electric field generated by the anode 801 is the same as (exactly the same or nearly the same as) the size A of the effective electroplating area of ​​the substrate 802. Therefore, the uniformity of the electric field distribution can be improved, and the electric field strength at each location in the effective electroplating area of ​​the substrate 802 can be made closer to each other. In addition, this can improve the uniformity of the electroplating height on the surface of the substrate 802.

[0026] The effective electroplating region of substrate 802 is the region where metal is deposited. For example, when a circular substrate 802 with a diameter of 200 mm is held by a clamp 809, there is a 1 mm wide annular region at the edge of substrate 802 that is enclosed by the lip seal of the clamp 809. Since metal is not deposited in this annular region, the diameter of the effective electroplating region of substrate 802 is 198 mm.

[0027] The sensor 8012 is fixed to the outer wall of the electrolytic plating bath 808. The sensor 8012 detects whether the upper surface 810 of the anode 801 is at a set height, thereby maintaining the distance between the upper surface 810 of the anode 801 and the substrate 802 at a set value. Specifically, the sensor 8012 is located on the same plane as the upper surface 810 of the anode 801, and the upper surface 810 of the anode 801 is detected by the sensor 8012.

[0028] A cover may be placed over the sensor 8012 to prevent it from being contaminated or damaged by electrolytic plating solution overflowing from the electrolytic plating bath 808.

[0029] The anode 801 is formed by joining two or more small anodes in the horizontal direction.An anode support plate 8010 is provided at the bottom of the anode 801. The drive unit 8011 is located below the anode support plate 8010, and the output shaft of the drive unit 8011 is connected to the anode support plate 8010.

[0030] The controller 8013 is connected to the sensor 8012 and the drive unit 8011, respectively.

[0031] During the electroplating process, the anode 801 is gradually consumed. Since the upper surface 810 of the anode 801 is consumed uniformly, the shape of the upper surface 810 remains unchanged. Therefore, the size of the cross-sectional area of ​​the electric field generated by the anode 801 does not change. When the height of the upper surface 810 of the anode 801 decreases, the upper surface 810 can no longer be detected by the sensor 8012. At this time, the sensor 8012 transmits a first signal to the controller 8013. After receiving the first signal, the controller 8013 sends a command to the drive unit 8011, which moves the output shaft of the drive unit 8011 to slowly raise the anode 801 until the sensor 8012 can detect the upper surface 810 of the anode 801 again. At this time, the sensor 8012 transmits a second signal to the controller 8013. After receiving the second signal, the controller 8013 sends a command to the drive unit 8011, which stops operating. This allows the upper surface 810 of the anode 801 to always be kept at a set height, and the distance between the upper surface 810 of the anode 801 and the substrate 802 to remain constant. As a result, the processing results can be made more stable, not changing in accordance with the wear of the anode.

[0032] Furthermore, based on the amount of anode metal consumed, which is periodically calculated by the controller, the change in the height of the upper surface 810 of the anode 801 can be estimated, and the drive unit 8011 can be controlled accordingly to raise the upper surface 810 of the anode 801 to its initial position. The amount of anode metal consumed is related to factors such as the electroplating current, energizing time, and electroplating efficiency, and specific calculation methods can be found in Japanese Patent Publication JP1983113399A. The amplitude of each operation of the drive unit 8011 should be kept as small as possible to prevent the upper surface 810 of the anode 801 from coming off the O-shaped seal ring 805 and causing a sealing failure.

[0033] As shown in Figure 9, after performing the electroplating process for a certain period of time, the thickness of the anode 801 decreases, but the upper surface of the anode 801 is maintained at a constant height.

[0034] In this embodiment, the sensor 8012 is an infrared sensor and comprises a transmitting sensor and a receiving sensor. View windows are provided on both sides of the electrolytic plating tank 808. When infrared rays emitted by the transmitting sensor pass through the view window and are detected by the receiving sensor on the opposite side, the upper surface 810 of the anode 801 is below a set height. At this time, it is necessary to raise the anode 801 so that the upper surface 810 of the anode 801 reaches the set height.

[0035] In another embodiment, the sensor 8012 may be a contact sensor having an elastic contact. The contact of the sensor 8012 is mounted on the upper part of the positioning cylinder 804. When the anode 801 is below a set height, the contact does not contact the upper surface 8109 of the anode 801. In this case, it is necessary to raise the anode 801 so that the upper surface 8109 of the anode 801 comes into contact with the contact.

[0036] The number of O-shaped sealing rings 805 can be increased to two or more.

[0037] (Fourth Embodiment) As shown in Figure 10, this embodiment provides an electroplating apparatus comprising an anode 901, a positioning cylinder 904, an ion film 906, a diffuser plate 907, an electroplating tank 908, a clamp 909, an anode support plate 9010, a drive unit 9011, a sensor 9012, and a controller 9013. The electroplating tank 908 is used to hold 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 faces the substrate 902 parallel to it. The ion film 906 is located above the anode 901 and is used to separate the electroplating solution on the anode side from the electroplating solution on the cathode side in the electroplating tank 908. The diffuser plate 907 is located between the ion film 906 and the substrate 902. The diffuser plate 907 also has a plurality of small holes for the electroplating solution 903 to pass through. The anode 901 is located inside 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 bath 908. The shape of the inner wall of the positioning cylinder 904 matches that of the anode 901, and the center of the upper surface 910 of the anode 901 is aligned with the center of the substrate 902.

[0038] The inner wall of the positioning cylinder 904 is provided with an upper seal ring 9051, a lower seal ring 9052, and an annular groove 9014. The positioning cylinder 904 also contains a water inlet passage 9015 and a water outlet passage 9016. The upper seal ring 9051 seals tightly to the upper part of the side wall of the anode 901 such that only the upper surface 910 of the anode 901's surface area is in contact with the electroplating solution 903. Therefore, the electric field generated by the anode 901 is completely discharged from the upper surface 910. The anode 901 may be cylindrical. Since the size B of the upper surface 910 of the anode 901 is the same as the size A of the effective electroplating area of ​​the substrate 902, the size of the cross-section of the electric field generated by the anode 901 is the same (exactly the same or nearly the same) as the size A of the effective electroplating area of ​​the substrate 902. Therefore, the uniformity of the electric field distribution is improved, and the electric field strength at each location in the effective electroplating area of ​​the substrate 902 can be made closer to each other. Furthermore, this improves the uniformity of the electrolytic plating height on the surface of the substrate 902.

[0039] As shown in Figure 11, the lower seal ring 9052 is located below the upper seal ring 9051, and the annular groove 9014 is located between the upper seal ring 9051 and the lower seal ring 9052. The upper part of the water inlet passage 9015 is connected to the annular groove 9014, and the bottom part is connected to the water inlet pump 9017. The water inlet pump 9017 is used to transport liquid from the outside into the annular groove 9014. The upper part of the water outlet passage 9016 is connected to the annular groove 9014, and the bottom part is connected to the water outlet pump 9018. The water outlet pump 9018 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 continue to operate, keeping the liquid, such as water, in the annular groove 9014 in a flowing state. In this state, new liquid flows from the water inlet passage 9015 into the annular groove 9014 and then flows out from the water outlet passage 9016. If the upper seal ring 9051 leaks, the electroplating solution 903 leaks downward and enters the annular groove 9014, where it is then diluted by the liquid in the annular groove 9014. Since the diluted electroplating solution 903 flows out through the water outlet passage 9016, it does not accumulate in the annular groove 9014 and does not corrode the side wall of the anode 901. The lower seal ring 9052 prevents the liquid from leaking downward and contaminating the drive unit 9011. It is preferable to provide the water inlet passage 9015 and the water outlet passage 9016 at both radial ends of the annular groove 9014 so that the liquid in the annular groove 9014 flows sufficiently and the electroplating solution 903 is sufficiently diluted.

[0040] The sensor 9012 is fixed to the outer wall of the electrolytic plating bath 908. The sensor 9012 detects whether the upper surface 910 of the anode 901 is at a set height, thereby maintaining the distance between the upper surface 910 of the anode 901 and the substrate 902 at a set value. Specifically, the sensor 9012 is located on the same plane as the upper surface 910 of the anode 901, and the upper surface 910 of the anode 901 is detected by the sensor 9012.

[0041] A cover may be provided over the sensor 9012 to prevent it from being contaminated or damaged by electrolytic plating solution overflowing from the electrolytic plating bath 908.

[0042] The anode 901 is formed by joining two or more small anodes in the horizontal direction. An anode support plate 9010 is provided at the bottom of the anode 901. The drive unit 9011 is located below the anode support plate 9010, and the output shaft of the drive unit 9011 is connected to the anode support plate 9010.

[0043] The controller 9013 is connected to the sensor 9012 and the drive unit 9011, respectively.

[0044] During the electroplating process, the anode 901 is gradually consumed. Since the upper surface 910 of the anode 901 is consumed uniformly, the shape of the upper surface 910 remains unchanged. Therefore, the size of the cross-sectional area of ​​the electric field generated by the anode 901 does not change. When the height of the upper surface 910 of the anode 901 decreases, the upper surface 910 can no longer be detected by the sensor 9012. At this time, the sensor 9012 transmits a first signal to the controller 9013. After receiving the first signal, the controller 9013 sends a command to the drive unit 9011, which moves the output shaft of the drive unit 9011 to slowly raise the anode 901 until the sensor 9012 can detect the upper surface 910 of the anode 901 again. At this time, the sensor 9012 transmits a second signal to the controller 9013. After receiving the second signal, the controller 9013 sends a command to the drive unit 9011, which stops operating. This allows the upper surface 910 of the anode 901 to be kept at a set height at all times, and the distance between the upper surface 910 of the anode 901 and the substrate 902 to be kept constant. As a result, the processing results can be made more stable, not changing in accordance with the wear of the anode.

[0045] Furthermore, based on the amount of metal consumed by the anode, which is periodically calculated by the controller, the change in the height of the upper surface 910 of the anode 901 can be estimated, and the drive unit 9011 can be controlled accordingly to raise the upper surface 910 of the anode 901 to its initial position.

[0046] In this embodiment, the sensor 9012 is an infrared sensor and comprises a transmitting sensor and a receiving sensor. View windows are provided on both sides of the electrolytic plating tank 908. When infrared rays emitted by the transmitting sensor pass through the view window and are detected by the receiving sensor on the opposite side, the upper surface 910 of the anode 901 is below a set height. At this time, it is necessary to raise the anode 901 so that the upper surface 910 of the anode 901 reaches the set height.

[0047] (Fifth embodiment) As shown in Figure 12, this embodiment provides an electroplating apparatus comprising an anode 1001, a positioning cylinder 1004, an electroplating tank 1008, and a clamp 1009. The electroplating tank 1008 is used to hold the electroplating solution 1003. The clamp 1009 is used to hold the substrate 1002. Both the anode 1001 and the substrate 1002 are vertically immersed in the electroplating solution 1003. The right side 1010 of the anode 1001 faces the substrate 1002 parallel to it. The positioning cylinder 1004 is located inside the electroplating tank 1008, and the bottom of the positioning cylinder 1004 is connected to the inner wall of the electroplating tank 1008. The anode 1001 is located inside the positioning cylinder 1004. The right end of the positioning cylinder 1004 is open. 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 aligned with the center of the substrate 1002. The sealing member 1005 is provided at the contact portion between the positioning cylinder 1004 and the anode 1001 such that only the right surface 1010 of the surface area of ​​the anode 1001 is in contact with the electroplating solution 1003. As a result, the electric field generated by the anode 1001 is completely discharged from the right surface 1010. The anode 1001 may be cylindrical. Since the size of the right surface 1010 of the anode 1001 is the same as the size of the effective electroplating area of ​​the substrate 1002, the size of the cross-section of the electric field generated by the anode 1001 is the same as the size of the effective electroplating area of ​​the substrate 1002. Therefore, the uniformity of the electric field distribution can be improved, and the electric field strength at each location in the effective electroplating area of ​​the substrate 1002 can be brought closer together. In addition, this can improve the uniformity of the electroplating height on the surface of the substrate 1002.

[0048] (Sixth Embodiment) As shown in Figure 13, this embodiment provides an electroplating apparatus. This electroplating apparatus has all the structures of the electroplating apparatus described in the first embodiment, but the description will not be repeated here. In addition, an air intake port 1112 is provided at the bottom of the electroplating tank 1108. The air intake port 1112 is used to introduce air or oxygen into the electroplating solution, thereby completely oxidizing the metal ions in the electroplating solution and converting them into more stable metal ions under the action of oxygen.

[0049] (Seventh Embodiment) This embodiment provides an electroplating method. This electroplating method includes the steps of: installing a positioning cylinder in an electroplating bath, and positioning the anode inside the positioning cylinder such that the anode and the inner wall of the positioning cylinder are in airtight contact, wherein only the first surface of the anode is in contact with the electroplating solution on the surface region of the anode, the first surface of the anode is parallel to the substrate, the size of the first surface of the anode is the same as the size of the effective electroplating area of ​​the substrate, and the center of the first surface of the anode is aligned with the center of the substrate; A step of setting the distance between the first surface of the anode and the substrate, The process includes calculating the change in the distance between the first surface of the anode and the substrate, and driving the anode to move toward the substrate until the distance between the first surface of the anode and the substrate reaches a set value.

[0050] (Eighth embodiment) This embodiment provides an electroplating method. This electroplating method includes the steps of: installing a positioning cylinder in an electroplating bath, and positioning the anode inside the positioning cylinder such that the anode and the inner wall of the positioning cylinder are in airtight contact, wherein only the first surface of the anode is in contact with the electroplating solution on the surface region of the anode, the first surface of the anode is parallel to the substrate, the size of the first surface of the anode is the same as the size of the effective electroplating area of ​​the substrate, and the center of the first surface of the anode is aligned with the center of the substrate; A step of setting the distance between the first surface of the anode and the substrate, The process involves detecting the position of the first surface of the anode through a sensor and transmitting a signal to the controller. The system includes the following steps: when the distance between the first surface of the anode and the substrate exceeds a set value, the sensor transmits a first signal to the controller, the controller receives the first signal and sends a command to the drive unit, the sensor drives the anode towards the substrate until the distance between the first surface of the anode and the substrate is equal to the set value again, the sensor transmits a second signal to the controller, the controller receives the second signal and sends a command to the drive unit, the drive unit stops operating.

[0051] To further stabilize the metal ions in the electroplating solution, an air intake is provided in the electroplating tank, allowing air or oxygen to be introduced into the solution. This completely oxidizes the metal ions under the action of oxygen, converting them into more stable metal ions.

[0052] In summary, the present invention discloses the relevant technology in specific and detail through the embodiments and related drawings described above, enabling those skilled in the art to implement the invention accordingly. The embodiments described above are used solely to illustrate the invention and not to limit it. The scope of the present invention is defined by the claims of the present invention. Modifications of the number of components disclosed herein, or substitutions of equivalent components, also fall within the scope of the present invention.

Claims

1. Electrolytic plating apparatus, An electrolytic plating tank configured to hold an electrolytic plating solution, A clamp configured to hold the circuit board, A positioning cylinder located inside the electrolytic plating tank, with one end open, An electroplating apparatus comprising: an anode located inside the positioning cylinder and in sealed contact with the positioning cylinder, wherein only a first surface of its entire surface area is in contact with the electroplating solution, the first surface is parallel to and opposite the substrate, the center of the first surface is aligned with the center of the substrate, and the size of the first surface is the same as the size of the effective electroplating area of ​​the substrate.

2. The electroplating apparatus according to claim 1, characterized in that the positioning cylinder is in sealed contact with the second surface of the anode, which is perpendicular to the first surface.

3. The electroplating apparatus according to claim 1, characterized in that the positioning cylinder is arranged vertically, at least one ring of a sealing member is provided on the inner wall of the positioning cylinder, the sealing member is in airtight contact with the upper part of the side surface of the anode, and the sealing member has a constant height in the vertical direction.

4. The electroplating apparatus according to claim 1, further comprising a drive unit and a controller, wherein the drive unit is connected to the anode and the controller, respectively, the controller periodically calculates the change in the distance between the first surface of the anode and the substrate and controls the drive unit, and the drive unit moves the anode toward the substrate so that the distance between the first surface of the anode and the substrate reaches a set value.

5. The electroplating apparatus according to claim 4, characterized in that the anode is arranged vertically, the anode is formed by joining two or more small anodes in the horizontal direction, an anode support plate is provided at the bottom of the anode, the drive device is located below the anode support plate, and the output shaft of the drive device is connected to the anode support plate.

6. The electrolytic plating apparatus according to claim 1, characterized in that the electrolytic plating tank is provided with an air intake port for introducing air or oxygen into the electrolytic plating solution.

7. The electroplating apparatus according to claim 1, further comprising a drive unit, a sensor, and a controller, wherein the drive unit is connected to the anode and the controller, respectively, the sensor is connected to the controller and installed in the electroplating bath, and is configured to detect the position of the first surface of the anode, a first signal or a second signal is transmitted by the sensor to the controller according to the detection result, the controller controls the drive unit according to the received first signal or second signal, and the drive unit 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.

8. The electroplating apparatus according to claim 7, wherein the sensor is an infrared sensor comprising a transmitting sensor and a receiving sensor, the electroplating tank is provided with two viewing windows, and the receiving sensor receives infrared radiation emitted by the transmitting sensor through the viewing windows.

9. The electroplating apparatus according to claim 7, wherein the sensor is a contact sensor having an elastic contact, the contact of the contact sensor is installed on the positioning cylinder, and if the distance between the first surface of the anode and the substrate is greater than the set value and the first surface of the anode and the contact are not in contact, the drive device drives the anode to move toward the substrate and bring the first surface of the anode into contact with the contact.

10. The electroplating apparatus according to claim 7, characterized in that at least one O-shaped sealing ring is provided on the inner wall of the positioning cylinder, and the at least one O-shaped sealing ring is in airtight contact with the upper part of the side wall of the anode.

11. The electroplating apparatus according to claim 7, characterized in that the positioning cylinder is arranged vertically, the inner wall of the positioning cylinder is provided with an upper seal ring, a lower seal ring, and an annular groove, the positioning cylinder is provided with a water inlet passage and a water outlet passage, the upper seal ring is in sealed contact with the upper part of the side wall of the anode, the lower seal ring is located below the upper seal ring, the annular groove is located between the upper seal ring and the lower seal ring, the upper part of the water inlet passage is connected to the annular groove and the bottom is connected to a water inlet pump, the water inlet pump is used to transport liquid from the outside to the annular groove, the upper part of the water outlet passage is connected to the annular groove and the bottom is connected to a water outlet pump, the water outlet pump is used to discharge the liquid in the annular groove to the outside.

12. An electrolytic plating method, A step of installing a positioning cylinder in an electroplating bath, and positioning the anode inside the positioning cylinder such that the anode and the inner wall of the positioning cylinder are in airtight contact, wherein only the first surface of the anode is in contact with the electroplating solution on the surface region 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 aligned with the center of the substrate, An electrolytic plating method comprising the steps of: installing a drive device in the electrolytic plating bath so as to be in contact with the anode; calculating or detecting a change in the distance between the first surface of the anode and the substrate; and controlling the operation 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 a set value.

13. The electroplating method according to claim 12, further comprising the step of introducing air or oxygen into the electroplating solution.

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