Wafer electroplating device with vertical upward surge

Abstract

Provided in the present application is a wafer electroplating device with vertical upward surge, comprising: an outer chamber, an inner chamber, a liquid conveying tube, and a liquid pump, wherein the inner chamber is fitted in the outer chamber and in communication with the outer chamber by means of the liquid conveying tube and the liquid pump; and workpiece hangers, which comprise an anode hanger used for bearing an anode part and a cathode hanger used for bearing a wafer, the anode hanger and the cathode hanger being vertically arranged facing each other, and the anode part and the wafer being arranged facing away from each other and having similar or identical sizes. At least one layer of flow adjuster is further provided on the side of the inner chamber close to the bottom of the inner chamber, said flow adjuster being located between a liquid inlet of the inner chamber and the workpiece hangers. The wafer electroplating device with vertical upward surge allows for uniform upward surge of a plating solution, and alleviates the problem of the plating solution surging vigorously at the liquid inlet and causing uneven concentration distribution of the plating solution that comes into contact with the wafer surface, resulting in non-uniform electroplating and the formation of voids and spots from pores enclosed in a plating layer.

Description

A vertical upwelling wafer electroplating device

[0001] This application claims priority based on the Chinese patent application filed with the State Intellectual Property Office of China on November 3, 2023, with application number: 202311460133.2, and the name of the invention: "A vertical upwelling wafer electroplating device". The disclosed content of the Chinese patent application is hereby introduced as a whole into the text of this application. Technical Field

[0002] The present application relates to the technical field of electroplating equipment, and in particular to an upwelling vertical wafer electroplating device. Background Art

[0003] Existing semiconductor wafer electroplating equipment primarily utilizes integrated horizontal electroplating equipment, with the anode fixed flat at the bottom and the cathode rotatably positioned parallel to the anode. The plating solution flows from bottom to top, or parallel to the direction of the cathode and anode. The advantages of horizontal electroplating equipment include: the cathode fixture can rotate or move up and down, making it easy to design automated electroplating fixtures, and utilizing rotation to disrupt the electric double layer effect on the cathode surface, allowing metal ions to easily enter the cathode. However, its main disadvantages include: when the fluid flows in the same direction as the electric field lines of force, the fluid flow can easily cause the lines of force to become chaotic, disrupting the uniformity of the electroplating deposition and causing deformation in the microstructure formed by electroplating. Furthermore, the fluid flow directly impacting the cathode wafer microstructure can easily cause a difference in deposition rate between the center and periphery of the cathode object. Furthermore, direct impact of the plating solution on the microstructure can easily cause bubbles to be drawn into the deep pores of the microstructure, forming encapsulated voids. When the plating solution flows in a direction parallel to the electrode, the impact force of the plating solution entering the liquid inlet of the electroplating chamber will cause local liquid vortex turbulence, which will not only easily generate bubbles flowing with the plating solution, but also cause uneven plating solution concentration and flow rate at the contact point with the wafer surface to be plated, affecting the final electroplating uniformity and consistency of the wafer surface.

[0004] Summary of the Invention

[0005] In view of this, embodiments of the present application provide a vertical upwelling wafer electroplating apparatus. This apparatus is designed to address the issues of uneven plating solution flow in existing horizontal wafer electroplating apparatuses, which can lead to plated voids and uneven plating on the wafer surface. This improves the stability of the electroplating process and ensures a uniform electroplating effect.

[0006] A vertical upwelling wafer electroplating device comprises: an outer chamber, an inner chamber, a liquid infusion pipe, and a liquid pump; the inner chamber is sleeved in the outer chamber and is connected to the outer chamber through the liquid infusion pipe and the liquid pump;

[0007] A workpiece hanger includes an anode hanger for carrying an anode component and a cathode hanger for carrying a wafer; the anode hanger and the cathode hanger are arranged vertically, the anode component and the wafer are arranged symmetrically with respect to the center, and the two have the same size and shape; or, the working surface of the anode component has the same size and shape as the surface of the wafer to be plated;

[0008] At least one layer of rectifying components is arranged in the inner chamber, and the rectifying components are located between the liquid inlet of the inner chamber and the workpiece hanger.

[0009] Furthermore, the parallel distance between the anode rack and the cathode rack is D1,2mm≤D1≤50mm.

[0010] Furthermore, the shortest distance between the rectifying member and the liquid inlet is D2, 10 mm ≤ D2 ≤ 100 mm.

[0011] Furthermore, at least two liquid inlets are provided at the bottom of the inner chamber, and a plurality of first branch nozzles are spaced apart at the first end of the delivery pipe, the first branch nozzles corresponding to the liquid inlets extending into the inner chamber, and the nozzles of the first branch nozzles are directed upward toward one side of the fairing; preferably, the nozzle directions of adjacent first branch nozzles can be staggered, or the nozzle directions of adjacent first branch nozzles can be arranged at a zigzag angle.

[0012] Furthermore, the ratio of the nozzle distance between adjacent first branch nozzles to the nozzle diameter between the first branch nozzles is between 15:1 and 3:1.

[0013] Furthermore, it includes two or more layers of parallel arranged straightening members, and the shortest distance between adjacent straightening members is D3, 10mm≤D3≤100mm; preferably, the mesh size of the straightening members is between 3-30 meshes.

[0014] Furthermore, an overflow channel communicating with the outer chamber is provided at the top of the inner chamber; the plating solution can flow back from the inner chamber to the outer chamber via the overflow channel.

[0015] The present application also provides a vertical upwelling wafer electroplating device capable of achieving double-sided wafer electroplating effect, wherein the anode rack comprises a first anode rack and a second anode rack, and in the horizontal direction, the cathode rack is arranged parallel to and between the first anode rack and the second anode rack;

[0016] The first anode rack and the second anode rack carry the first anode component and the second anode component respectively, and the cathode rack carries a double-sided wafer, which includes a first surface to be plated and a second surface to be plated, the first surface to be plated and the first anode component face opposite to each other, and the second surface to be plated and the second anode component face opposite to each other.

[0017] Furthermore, the first surface to be plated and the working surface of the first anode component have the same size and shape; the second surface to be plated and the working surface of the second anode component have the same size and shape.

[0018] Furthermore, the cathode rack includes a first cathode rack section and a second cathode rack section that can be assembled and fixed, the first cathode rack section includes a first cathode placement slot, and the second cathode rack section includes a second cathode placement slot; the first cathode placement slot and the second cathode placement slot face each other to form a accommodating cavity for double-sided wafers.

[0019] Furthermore, it includes a crystal support member, which is used to clamp and fix the double-sided wafer; a sealing ring is provided between the inner side wall of the first cathode placement groove and / or the second cathode placement groove and the circumferential wall of the crystal support member.

[0020] The vertical wafer electroplating device provided by the present application has an anode component vertically fixed on one side of the electroplating reaction chamber, and a cathode component wafer facing perpendicularly to the other side of the electroplating liquid chamber. The plating liquid is injected into the electroplating liquid chamber in an upward manner and flows, that is, the flow line of the plating liquid is perpendicular to the electric field lines of the anode and cathode, and the fluid flow does not cause confusion of the magnetic lines of force. In addition, by arranging at least one layer of rectifying components between the liquid inlet at the bottom of the electroplating reaction chamber and the workpiece holder, the fluid impact force of the liquid inlet of the electroplating reaction chamber can be prevented from disturbing the stability of the plating liquid in the chamber, forming a stable flow field, thereby maintaining uniform concentration and flow rate of the plating liquid flowing from bottom to top across the surface of the wafer to be plated, thereby improving the uniformity and stability of the electroplating deposition effect. Furthermore, due to the flow-balancing effect of the rectifying components, the probability of the plating liquid at the liquid inlet impacting the workpiece surface to generate bubbles and flowing upward with the plating liquid can be reduced or eliminated, thereby avoiding the phenomenon of bubbles remaining in the plating holes when the plating liquid contacts the wafer surface, causing electroplating voids, and further improving the electroplating effect on the wafer surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0022] FIG1 is a side view schematic diagram of a wafer electroplating device provided in Example 1 of the present application;

[0023] FIG2 is a schematic top view of the wafer electroplating apparatus shown in FIG1 ;

[0024] FIG3 is a schematic diagram of the exploded structure of a workpiece hanger provided in Example 1 of the present application;

[0025] FIG4 is a schematic structural diagram of the workpiece hanger shown in FIG3 after assembly;

[0026] FIG5 is a schematic cross-sectional view of the wafer electroplating apparatus shown in FIG2 along the line AA′;

[0027] FIG6 is a schematic top view of a rectifier provided in Example 1 of the present application;

[0028] FIG7 is a schematic cross-sectional view of the fairing shown in FIG6 taken along the line BB';

[0029] FIG8 is a side view schematic diagram of a double-sided wafer electroplating device provided in Example 2 of the present application;

[0030] FIG9 is a schematic top view of the wafer electroplating apparatus according to Embodiment 2 shown in FIG8 ;

[0031] FIG10 is an exploded schematic diagram of a double-sided cathode rack provided in Example 2 of the present application;

[0032] FIG11 is a schematic cross-sectional view of the wafer electroplating apparatus shown in FIG9 taken along line CC′. DETAILED DESCRIPTION

[0033] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0034] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a," "an," and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0035] It should be understood that the term "and / or" as used herein is merely a description of the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0036] In the description of this specification, it is necessary to understand that the words "substantially", "approximately", "approximately", "about", "roughly", "generally" and the like described in the claims and embodiments of this application refer to what can be generally recognized within a reasonable process operation range or tolerance range, rather than an exact value.

[0037] The "working surface" described in this specification refers to the plane where the electrochemical reaction occurs.

[0038] The embodiment of the present application provides a vertical wafer electroplating device, which is used to improve the problem of uneven plating solution flow in the existing horizontal wafer electroplating device, which causes void coating and uneven electroplating.

[0039] Example 1:

[0040] For example, Figure 1 is a side view schematic diagram of a wafer electroplating device provided in Example 1 of the present application; Figure 2 is a top view schematic diagram of the wafer electroplating device shown in Figure 1; Figure 3 is a decomposed structural schematic diagram of a workpiece holder provided in Example 1 of the present application; Figure 4 is a structural schematic diagram of the workpiece holder shown in Figure 3 after assembly; Figure 5 is a cross-sectional schematic diagram of the wafer electroplating device shown in Figure 2 along the A-A' direction; please refer to Figures 1 to 5, the wafer electroplating device 100 includes an outer chamber 11 and an inner chamber 12 which are nested together, and the outer chamber 11 is connected to an external liquid supply device (not shown in the figure) through a first liquid inlet 17, which is used to transfer the plating liquid to the outer chamber 11; the first liquid inlet 17 is located on the middle and lower side wall of the outer chamber 11, so that when the external plating liquid enters the outer chamber 11, it can avoid the plating liquid from impacting the inner side wall or inner bottom wall of the outer chamber 11 under the action of gravity to generate bubbles. The side wall of the outer chamber 11 also includes a first liquid outlet 111 and a first infusion port 112, and the bottom wall of the inner chamber 12 is provided with a plurality of evenly distributed second liquid inlets 120. The outer chamber 11 and the inner chamber 12 are connected by an infusion tube 16. One end of the infusion tube 16 is connected and extends into the outer chamber 11, and then passes through the first liquid outlet 111, the first infusion port 112, and the infusion tube 16 in sequence, and then the other end is extended into the inner chamber 12; specifically, as shown in Figure 1, the infusion tube 16 branches into a plurality of sub-infusion tube ends 161 before passing through the first infusion port 112 and extending into the inner chamber 12, and each sub-infusion tube end 161 is matched one by one to pass through the second liquid inlet 120. The infusion tube 16 is located between the first liquid outlet 111 and the first infusion port 112 and is connected to the liquid pump 15. Under the power drive of the liquid pump 15, the electroplating liquid in the outer chamber 11 can be transmitted to the inner chamber 12 through the infusion tube 16, and under the diversion effect of the sub-infusion tube end 161, the electroplating liquid entering the inner chamber 12 is a plurality of liquid streams. Compared with the single liquid stream entry method, the impact force of the liquid flow when entering can be reduced, and the stability of the electroplating liquid when entering the inner chamber 12 can be improved. The inner chamber 12 is a reaction chamber for the electroplating reaction process. When the electroplating liquid enters from the second liquid inlet 120 located at the bottom of the inner chamber 12, the electroplating liquid flows from bottom to top, which is an upwelling flow. By adopting the upwelling liquid transmission method, the gravity of the liquid itself can be used to balance the impact force of a part of the plating liquid when entering the inner chamber 12, and the degree of plating liquid surge in the flat area. In this way, the area of ​​contact between the edge of the wafer 20 near the second liquid inlet 120 and the plating liquid and the concentration of the plating liquid are not much different from the structure of the wafer 20 in contact with the smoothly flowing plating liquid at the top during the electroplating process, thereby improving the uniformity and stability of the electroplating effect of the entire wafer 20, thereby improving the product yield.

[0041] Optionally, as shown in FIG1 , the top height of the inner chamber 12 is lower than the top of the outer chamber 11, so that an overflow channel 60 is formed between the top of the inner chamber 12 and the top of the outer chamber 11. The plating solution in the inner chamber 12 can flow back to the outer chamber 11 through the overflow channel 60, and further mix and evenly mix with the plating solution in the outer chamber 11. Through the liquid pump 15, the infusion tube 16, and the overflow channel 60, the plating solution can circulate between the inner chamber 12 and the outer chamber 11, thereby improving the uniformity and stability of the concentration of the plating solution and the content of the plating solution components in contact with the wafer 20 during the entire electroplating process, thereby achieving uniformity in the coating. Further optionally, in other embodiments, an overflow port that is connected to the external embedded type can also be opened on the side wall of the top of the inner chamber 12, and the plating solution in the inner chamber 12 can flow back to the outer chamber 11 through the overflow port. This method also falls within the scope of protection of this application.

[0042] Continuing to refer to Figures 1, 2, and 5, the workpiece hangers 13 / 14 for carrying the anode 30 and cathode 20 are vertically placed in the inner chamber 12 in a split manner and face each other in parallel. The anode hanger 14 and the cathode hanger 13 may have the same structure, respectively fixing the anode 30 and cathode 20, and adjusting the distance between the anode hanger 14 and the cathode hanger 13 to adjust the distance between the actual electroplating anode 30 and cathode 20. Specifically, for ease of description, the embodiment of the present application uses a copper sheet as the anode 30 and a wafer 20 as the cathode 20 as an example. However, it should be noted that in other variable embodiments, the material of the anode 30 can be a soluble metal or an insoluble metal, including copper, nickel, silver, tin, and titanium-based precious metal oxide insoluble anodes, and the material of the wafer 20 can be a semiconductor material, including silicon, gallium arsenide, and silicon carbide. In the embodiment of the present application, the copper sheet is used as the anode and the silicon substrate is used as the wafer for exemplary description.

[0043] Please continue to refer to Figures 2 to 5. The inner wall of the inner chamber 12 is provided with a first cavity 121 and a second cavity 122 arranged opposite each other. The shape of the first cavity 121 is the same as the outer shape of the anode rack 14 and the size is equal to or slightly larger than the outer size of the anode rack 14. The shape of the second cavity 122 is the same as the outer shape of the cathode rack 13 and the size is equal to or slightly larger than the outer size of the cathode rack 13. During electroplating, the first cavity 121 and the second cavity 122 are respectively used to clamp and fix the anode rack 14 and the cathode rack 13 to prevent the latter from drifting in the distance between the copper sheet 30 and the silicon substrate 20, the current waveform, etc. due to external force or the flow of electroplating solution during electroplating, thereby affecting the uniformity and stability of the coating on the surface of the silicon substrate 20. Furthermore, two or more positioning rails (not shown) may be provided in the first cavity 121 or the second cavity 122. By adjusting the placement rails of the anode rack 14 or the cathode rack 13, the distance D1 between the anode rack 14 and the cathode rack 13 can be adjusted, thereby adjusting the electrode distance between the copper sheet 30 and the silicon substrate 20. Furthermore, the center distance D1 between the anode rack 14 and the cathode rack 13 can be set to 2mm≤D1≤100mm, preferably 5mm≤D1≤50mm; more preferably 10mm≤D1≤30mm. If the center distance D1 is too small, the effective flow of the electroplating solution in the channel between the anode and cathode is affected, reducing the electroplating efficiency. If D2 is too large, the electric field between the anode and cathode is uneven, affecting the deposition uniformity of the coating on the wafer surface and reducing the electroplating effect.

[0044] Continuing with Figures 2, 3, and 4, the anode rack 14 and cathode rack 13 include an anode alignment hole 141 and a cathode alignment hole 131, respectively. The anode alignment hole 141 is used to expose the actual size of the copper sheet 30, while the cathode alignment hole 131 is used to expose the size of the silicon substrate 20 to be plated. The shape and size of the anode alignment hole 141 are comparable to those of the cathode alignment hole 131. In practice, the shape and size of the portion of the anode exposed in the anode alignment hole 141 are the same as the shape and size of the portion of the wafer exposed in the cathode alignment hole 131. Optionally, as shown in Figure 2, the anode alignment hole 141 of the anode rack 14 and the cathode alignment hole 131 of the cathode rack 13 are symmetrically positioned in the center of the inner chamber 12, and the anode alignment hole 141 and the cathode alignment hole 131 are the same size and shape. This means that the size and shape of the copper sheet 30 and the cathode of the silicon substrate 20 are comparable, and the copper sheet 30 and the silicon substrate 20 are arranged facing each other.

[0045] Specifically, as shown in Figures 3 and 4, the anode hanger 14 and the cathode hanger 13 in this embodiment adopt the same structure. The cathode hanger 13 will be taken as an example for detailed introduction below. The cathode hanger 13 includes a hanger body 151, a crystal back plate 152 and a cover 153. The hanger includes a through placement groove 154. The bottom of the placement groove 154 is provided with a mounting groove 1541. The bottom of the mounting groove 1541 is provided with a cathode alignment hole 131. The aperture of the cathode alignment hole 131 is smaller than the aperture size inside the mounting groove 1541. The inside of the mounting groove 1541 is provided with a sealing ring 1513 distributed at multiple points or arranged in a whole circle around the cathode alignment hole 131. The thickness of the sealing ring 1513 is greater than the depth of the mounting groove 1541. When securing the silicon substrate 20, the silicon substrate 20 is first aligned and placed in the mounting groove 1541. The wafer carrier back plate 152 is then placed in place. The positioning blocks 1522 on the wafer carrier back plate 152 are aligned and engaged with the positioning holes 1517 in the mounting groove 1541 to secure the silicon substrate 20 in the mounting groove 1541. The cover 153 is then aligned and locked with the placement groove 154, pressing the wafer carrier back plate 152 firmly into the placement groove 154. It will be appreciated that the hanger body 151 and cover 153 are separate structures and are detachably connected, thereby facilitating the removal and placement of the silicon substrate 20. By setting a sealing ring 1513 at the bottom of the placement groove 154, when the silicon substrate 20 is placed in the placement groove 154 and the cover 153 is sealed and connected to the hanger body 151, the silicon substrate 20 is pressed against the sealing ring 1513, thereby forming a reliable seal to prevent the plating solution from affecting the other side of the silicon substrate 20. A conductive ring 1511 is provided at the bottom of the placement groove 154, contacting the silicon substrate 20. A conductive post 18 is provided on the hanger body 151, contacting and conducting the conductive ring 1511. The conductive post 18 is connected to the negative electrode of an external power source via a conductive portion 1515 exposed on the surface of the hanger body 151, thereby connecting the silicon substrate 20 to the negative electrode. It is readily understood that when the anode hanger 14 is used, the conductive post 18 is connected to the positive electrode of an external power source via a conductive portion 1515 exposed on the surface of the hanger body 151, thereby connecting the copper sheet 30 to the positive electrode. During electroplating, the copper anode contacts the plating solution to achieve electroplating on the silicon substrate 20. The specific electroplating principles of the silicon substrate 20 are conventional and will not be elaborated here.

[0046] Further optionally, the diameter width of the anode alignment hole 141 / cathode alignment hole 131 gradually increases along the direction of the crystal back plate 152 pointing to the anode alignment hole 141 / cathode alignment hole 131. If the anode alignment hole 141 / cathode alignment hole 131 is a wedge-shaped structure, it can limit the reaction area and improve the fluid flow pattern. The wedge-shaped structure is formed by the chamber frame.

[0047] Furthermore, a conductive ring 1511 is provided at the bottom of the placement groove 154 for contact with the silicon substrate 20 to evenly distribute the charge on the conductive layer on the surface of the silicon substrate 20. The hanger body 151 is also provided with a conductive post 18 that contacts and conducts with the conductive ring 1511. The electrical connection 181 on the conductive post 18 is connected to the negative electrode of the external power supply 10, thereby connecting the silicon substrate 20 to the negative electrode. Simultaneously, the electrical connection 181 on the anode hanger 14 is connected to the positive electrode of the external power supply 10. The specific principles of electroplating the silicon substrate 20 are conventional and will not be further described here.

[0048] Further, referring to FIG4 , a pressure sensor 1516 is disposed at the bottom of placement groove 154, near silicon substrate 20. Along the direction of movement of silicon substrate 20 within placement groove 154, the orthographic projection of the periphery of silicon substrate 20 on the bottom of placement groove 154102 at least partially overlaps with pressure sensor 1516. Pressure sensor 1516 can be specifically implemented as an annular thin-layer pressure sensor 1516. By providing pressure sensor 1516 to detect the pressure at the bottom of placement groove 154, the sealing and pressing condition of silicon substrate 20 and the chamber body can be monitored.

[0049] Continuing with Figures 1, 2, and 5, two layers of flow straighteners 40 are positioned within the inner chamber 12 between the first infusion section 161 of the infusion tube 16 and the bottom end of the workpiece hanger 13 / 14. The minimum distance D3 between two adjacent layers of flow straighteners is 10 mm ≤ D3 ≤ 100 mm; preferably, 15 mm ≤ D3 ≤ 50 mm; and more preferably, 20 mm ≤ D3 ≤ 30 mm. In other alternative embodiments, one or more layers of flow straighteners 40 may be provided. For ease of description, the present embodiment illustrates two layers of flow straighteners 40. The flow straighteners 40 are used to smooth the upward flow of the plating solution. When the plating solution, which has a high impact force, is ejected from the nozzle 50 and passes through the flow straighteners 40, the violent surge is smoothed, resulting in a calm and uniform flow distribution. This also eliminates bubbles and prevents the formation of mottling on the plating layer surface, improving the plating effect on the silicon substrate 20 and preventing mottling. The presence of the rectifying element 40 also balances the concentration and flow rate of the plating solution between the copper sheet 30 and the silicon substrate 20, preventing the plating solution from surging near the liquid inlet, which results in a lower probability of contact between the plating solution molecules and the silicon substrate 20 than at other normal locations. This improves the edge effect during electroplating on the silicon substrate 20, which can lead to uneven coating. Furthermore, the distance between the rectifying element and the second liquid inlet is D2, 10mm≤D2≤100mm, preferably 20mm≤D2≤50mm. When D2 is too small, the rectifying element cannot effectively smooth the impact of the liquid at the liquid inlet and will affect the stability of the rectifying element itself, preventing a smooth flow field. When D2 is too large, the effectiveness of the rectifying element is greatly reduced. Furthermore, the ratio of the distance between adjacent nozzles to their diameters can be set between 15:1 and 3:1, and the orientations of adjacent nozzles 50 are arranged at an angle. Typically, the angle of the nozzles 50 is between 30° and 150°, preferably between 60° and 120°.

[0050] Specifically, Figure 6 is a top view schematic diagram of a rectifier provided in an embodiment of the present application; Figure 7 is a B-B' cross-sectional schematic diagram of the rectifier shown in Figure 6; please refer to Figures 6 and 7, the rectifier 40 is a planar structure, with evenly distributed through mesh holes 401 on it, the mesh size of the mesh holes 401 is between 5 and 50, and the mesh spacing 401 is usually set between 1 and 20 mm, and the diameter of the mesh holes 401 is between 0.1 and 4 mm; further, along the upward direction of the plating solution, the diameter of the mesh holes 401 gradually increases, presenting a structure similar to a cone or a trumpet, and the height h of the rectifier is 10 mm ≤ h ≤ 100 mm, preferably 20 mm ≤ h ≤ 50 mm; the height of the rectifier has a significant effect on the flow guidance, which is similar to the distance between the first rectifier and the second rectifier. After passing through the rectifying element 40, the plating solution continues to flow upward through the gap between the copper sheet 30 and the silicon substrate 20, and then flows upward through the overflow channel 60 and back into the outer chamber 11, where it mixes with the plating solution in the outer chamber 11. This achieves repeated circulation of the plating solution between the inner chamber 12 and the outer chamber 11. Preferably, the top edge of the inner chamber 12 has a smooth, outward-expanding curvature to reduce the risk of plating solution overflowing from the inner chamber 12 and accumulating on the outer wall of the inner chamber 12.

[0051] Example 2:

[0052] Embodiment 2 of the present application also provides a vertical wafer electroplating device 200 that can achieve double-sided electroplating effect on wafers. Figure 8 is a side view schematic diagram of a double-sided wafer electroplating device provided in embodiment 2 of the present application; Figure 9 is a top view schematic diagram of the wafer electroplating device shown in Figure 8; Figure 10 is a decomposed schematic diagram of a double-sided cathode rack provided in embodiment 2 of the present application; Figure 11 is a C-C' cross-sectional schematic diagram of the wafer electroplating device shown in Figure 9; as shown in Figures 8 to 11, the vertical wafer electroplating device 200 includes a first anode rack 141, a second anode rack 142 and a double-sided cathode rack 130. In the horizontal direction, the double-sided cathode rack 130 is located between the first anode rack 141 and the second anode rack 142. The first anode rack 141 and the second anode rack 142 can be manufactured using the same structure as the anode rack 14 described in the above embodiment, and their structural features are not further described here. The first anode rack 141 and the second anode rack 142 respectively support the first anode component 301 and the second anode component 302, and are provided with a first anode alignment hole 1401 and a second anode alignment hole 1402 that expose the first anode component 301 and the second anode component 302. The openings of the first anode alignment hole 1401 and the second anode alignment hole 1402 are parallel to the cathode alignment holes 13103 / 13104 of the central double-sided cathode rack 130.

[0053] The double-sided cathode rack 130 in this embodiment is used to carry double-sided wafers 201 to be plated. In order to achieve double-sided electroplating of the wafer 201, the front and back surfaces of the wafer 201 to be plated need to be exposed. Therefore, it is different from the single-sided cathode rack structure 13 introduced in the above embodiment 1.

[0054] Specifically, as shown in FIG. 10 and FIG. 11 , the double-sided cathode rack 130 includes a first cathode rack section 1311 , a second cathode rack section 1312 , and an insulating crystal ring 1520 . In this embodiment, the first cathode hanger section 1311 and the second cathode hanger section 1312 have the same structure and are substantially the same as the structure of the hanger body of the single-sided cathode hanger described in the embodiments shown in Figures 1 to 5 above; please continue to refer to Figures 8, 9, and 10. The first cathode hanger section 1311 includes a first cathode placement groove 1310, and the bottom of the first cathode placement groove 1310 is provided with a first mounting groove 13101. The bottom of the first mounting groove 13101 is provided with a first cathode alignment hole 13103, and the aperture of the first cathode alignment hole 13103 is smaller than the aperture size inside the first mounting groove 13101. The bottom of the first mounting groove 13101 is provided with a first sealing ring 1513 distributed at multiple points or arranged in a full circle around the first cathode alignment hole 13103. The bottom of the first cathode placement groove 1310 is provided with a first conductive ring 13102 that contacts the silicon substrate 201. The first conductive ring 13102 is located on the side of the first sealing ring 1513 away from the first cathode alignment hole 13103. The first cathode hanger subsection 1311 is also provided with a first conductive post 18 that contacts and conducts electricity to the first conductive ring 13102. The electrical connection portion 181 on the first conductive post 18 is connected to the negative electrode of an external power source, thereby connecting the first surface to be plated of the double-sided silicon substrate 201, which is in direct contact with the first conductive ring 13102, to the negative electrode of the external power source. The insulating crystal support ring 1520 is a ring-shaped structure with a through-hole. Its inner ring structure is designed to match the outer shape and size of the double-sided silicon substrate 201, and its outer ring structure is designed to match the shape and size of the inner wall of the first cathode placement groove 1310 of the first cathode hanger subsection 1311. When the double-sided silicon substrate 201 is assembled and installed with the first cathode rack section 1311 and the second cathode rack section 1312 , the insulating wafer ring 1520 provides a clamping and fixing function for the double-sided silicon substrate 201 .

[0055] When installing the double-sided silicon substrate 201, please continue to refer to Figure 10, put the double-sided silicon substrate 201 on the insulating crystal ring 1520, and then align it and place it in the first cathode placement groove 1310 of the first cathode hanger division 1311, and the first surface to be plated of the double-sided silicon substrate 201 is embedded in the first installation groove 13101; then align the second cathode placement groove 13120 of the second cathode hanger division 1312 with the other side of the insulating crystal ring 1520, so that the second surface to be plated of the silicon substrate 201 is locked. The plating surface is embedded in the second mounting groove 13121 of the second cathode hanger division 1312; finally, the first cathode hanger division 1311 and the second cathode hanger division 1312 are assembled and fixed by the locking structure of the two, and the double-sided silicon substrate 201 is also fixed between the first cathode hanger division 1311 and the second cathode hanger division 1312, and the first surface to be plated and the second surface to be plated of the double-sided silicon substrate 201 are exposed respectively through the first cathode alignment hole 13103 and the second cathode alignment hole 13104.

[0056] Furthermore, at least two positioning blocks 1521 are respectively provided on the front and back sides of the insulating crystal ring 1520, and at least two positioning holes 1522 are provided at the bottom of the first cathode placement groove 1310. During assembly and installation, the silicon substrate 201 can be accurately aligned and securely fixed through the above-mentioned positioning blocks 1521 and positioning holes 1522.

[0057] Furthermore, a second sealing ring 134 is provided on the side wall of the first cathode placement groove 1310. The second sealing ring 134 can be embedded in the side wall or be an independent and flexibly removable rubber ring; or, a limiting groove is provided on the outer circumferential wall of the insulating crystal supporting ring 1520; when the insulating crystal supporting ring 1520 and the first cathode hanger division 1311 and the second cathode hanger division 1312 are assembled, the second sealing ring 134 is pressed between the outer circumferential wall of the insulating crystal supporting ring 1520 and the inner diameter side wall of the first cathode hanger division 1311 / the second cathode hanger division 1312 to achieve sealing between the insulating crystal supporting ring 1520 and the side wall of the first cathode hanger division 1311 / the second cathode hanger division 1312, thereby preventing the plating solution from contacting the first conductive ring 13102 through the gap between the two components, thereby further improving the sealing reliability.

[0058] Optionally, in some embodiments, the first anode element 301 and the first surface to be plated of the double-sided wafer 201 have the same shape and size, and the second anode element 302 and the second surface to be plated of the wafer 201 have the same shape and size. The shapes and sizes of the first and second surfaces to be plated of the double-sided wafer 201 can be set to be equivalent or different, and this application does not limit this. It should be noted that in actual products, "equivalent" means completely identical or within a reasonable range of error.

[0059] Specifically, please continue to refer to Figures 8 to 11. The first surface to be plated and the second surface to be plated of the silicon substrate 201 have the same shape and size, and the first anode component 301 and the second anode component 302 also have the same shape and size; in this way, a uniform electroplating effect can be achieved on both sides of the silicon substrate 201.

[0060] It can be selected that the part of the first anode component 301 exposed in the anode alignment hole 141 (working surface) and the first surface to be plated of the double-sided wafer 201 exposed in the anode alignment hole 141 have the same shape and size, and the part of the second anode component 302 exposed in the anode alignment hole 141 (working surface) and the second surface to be plated of the wafer 201 have the same shape and size.

[0061] In addition to the above-mentioned differences, the wafer electroplating device in this embodiment has all the technical features of the wafer electroplating device in the embodiments shown in Figures 1 to 5 above, and will not be described in detail here.

[0062] It should be noted that, in this embodiment, the second cathode hanger section 1311 has the same structure as the first cathode hanger section 1311. Given that the structure of the first cathode hanger section 1311 has been described above as an example, it is not difficult to understand that the structure of the second cathode hanger body side is also clear and definite.

[0063] The vertical wafer electroplating device provided by the present application has an anode component vertically fixed on one side of the electroplating reaction chamber, and a cathode component wafer facing perpendicularly to the other side of the electroplating liquid chamber. The plating liquid is injected into the bottom of the electroplating liquid chamber in an upward manner, that is, the flow line of the plating liquid is perpendicular to the electric field lines of the anode and cathode, and the fluid flow will not cause confusion of the electric field lines. In addition, by arranging at least one layer of rectifying components between the liquid inlet at the bottom of the electroplating reaction chamber and the workpiece holder, the fluid impact force of the liquid inlet of the electroplating reaction chamber can be broken to disrupt the stability of the plating liquid in the chamber, and a stable flow field can be formed, thereby maintaining uniform concentration and flow rate of the plating liquid flowing from bottom to top through the surface of the wafer to be plated, thereby improving the uniformity and stability of the electroplating deposition effect. Furthermore, due to the flow-equalizing effect of the rectifying components, the probability of the plating liquid at the liquid inlet impacting the workpiece surface to generate bubbles and flowing upward with the plating liquid can be reduced or eliminated, thereby avoiding the phenomenon of bubbles remaining in the plating holes when the plating liquid contacts the wafer surface, causing electroplating voids, and further improving the electroplating effect on the wafer surface.

[0064] It should be understood that the embodiments described above are only a portion of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other implementations obtained by simple combination or modification by a person of ordinary skill in the art are within the scope of protection of the present application. Industrial Applicability

[0065] The present application provides a vertical upwelling wafer electroplating device, comprising: an outer chamber, an inner chamber, an infusion tube, and a liquid pump; the inner chamber is arranged in a sleeve of the outer chamber and is connected to the outer chamber through the infusion tube and the liquid pump; a workpiece hanger, comprising an anode hanger for carrying an anode component and a cathode hanger for carrying a wafer; the anode hanger and the cathode hanger are arranged vertically opposite to each other, and the anode component and the wafer are arranged opposite to each other and have similar or identical sizes; at least one layer of rectifying components is further arranged on one side of the inner chamber close to the bottom of the inner chamber, and the rectifying components are located between the liquid inlet of the inner chamber and the workpiece hanger; the vertical wafer electroplating device can realize upwelling uniform flow of plating solution, improve the uneven distribution of plating solution concentration in contact with the wafer surface caused by the violent surge of plating solution at the liquid inlet, resulting in uneven electroplating and pores and spots in the plating layer, and has industrial applicability.

Claims

1. A vertical upwelling wafer electroplating device, characterized in that: include: An outer chamber, an inner chamber, an infusion tube, and a liquid pump; the inner chamber is sleeved on the outer chamber and is connected to the outer chamber through the infusion tube and the liquid pump; A workpiece hanger, comprising an anode hanger for carrying an anode component and a cathode hanger for carrying a wafer; the anode hanger and the cathode hanger are arranged vertically and face each other, the anode component and the wafer face are arranged symmetrically toward the center, and the two have the same size and shape, or the working surface of the anode component and the surface of the wafer to be plated have the same size and shape; At least one layer of rectifying components is arranged in the inner chamber, and the rectifying components are located between the liquid inlet of the inner chamber and the workpiece hanger.

2. The wafer electroplating device according to claim 1, characterized in that: The parallel distance between the anode hanger and the cathode hanger is D1, 2mm≤D1≤50mm.

3. The wafer electroplating device according to claim 1, characterized in that: The distance between the rectifying member and the liquid inlet is D2, 10mm≤D2≤100mm.

4. The wafer electroplating device according to claim 1, characterized in that: At least two liquid inlets are arranged at the bottom of the inner chamber, and a plurality of first branch nozzles are arranged at intervals at the first end of the delivery pipe, wherein the first branch nozzles correspond to the liquid inlets extending into the inner chamber, and the nozzles of the first branch nozzles are upwardly directed toward one side of the fairing; preferably, the nozzles of adjacent first branch nozzles are arranged in a staggered manner, or the nozzles of adjacent first branch nozzles are arranged in a zigzag angle.

5. The wafer electroplating device according to claim 4, characterized in that: The ratio of the nozzle distance between adjacent first branch nozzles to the nozzle diameter size between the first branch nozzles is between 15:1 and 3:

1.

6. The wafer electroplating device according to claim 4, characterized in that: The included angle between adjacent nozzles is between 30°C and 150°C, preferably between 60°C and 120°C.

7. The wafer electroplating device according to claim 1, characterized in that: It comprises two or more layers of the rectifying parts arranged in parallel, and the distance between adjacent rectifying parts is D3, 10mm≤D3≤100mm.

8. The wafer electroplating device according to claim 1, characterized in that: The mesh size of the fairing is between 3 and 30.

9. The wafer electroplating device according to claim 1, characterized in that: The mesh spacing of the rectifier is between 1-20 mm, and the diameter of the mesh is between 0.1 and 4 mm.

10. The wafer electroplating device according to claim 9, characterized in that: Along the upward direction of the electroplating solution, the diameter of the mesh gradually increases; preferably, it presents a conical or trumpet-shaped structure.

11. The wafer electroplating device according to claim 9, characterized in that The height h of the rectifying member is 10 mm ≤ h ≤ 100 mm, preferably 20 mm ≤ h ≤ 50 mm.

12. The wafer electroplating device according to claim 1, characterized in that: An overflow channel communicating with the outer chamber is disposed at the top of the inner chamber; the plating solution can flow back from the inner chamber to the outer chamber via the overflow channel.

13. The wafer electroplating device according to any one of claims 1 to 12, characterized in that: The anode rack comprises a first anode rack and a second anode rack, and in the horizontal direction, the cathode rack is arranged in parallel between the first anode rack and the second anode rack; The first anode rack and the second anode rack carry a first anode component and a second anode component respectively, and the cathode rack carries a double-sided wafer, and the double-sided wafer includes a first surface to be plated and a second surface to be plated, the first surface to be plated faces opposite to the first anode component, and the second surface to be plated faces opposite to the second anode component.

14. The wafer electroplating device according to claim 13, characterized in that: The first surface to be plated and the first anode component are comparable in size and shape; the second surface to be plated and the second anode component are comparable in size and shape.

15. The wafer electroplating device according to claim 13, characterized in that: The cathode hanger includes a first cathode hanger section and a second cathode hanger section which can be assembled and fixed, wherein the first cathode hanger section includes a first cathode placement slot and the second cathode hanger section includes a second cathode placement slot; the first cathode placement slot and the second cathode placement slot face each other to enclose a receiving cavity for the double-sided wafer.

16. The wafer electroplating device according to claim 15, characterized in that: It comprises a crystal support member, and the crystal support member is used for clamping and fixing the double-sided wafer; a sealing ring is arranged between the inner side wall of the first cathode placement groove and / or the second cathode placement groove and the circumferential wall of the crystal support member.

17. The wafer electroplating device according to claim 16, characterized in that: A positioning block is provided on the outer circumference of the crystal receiving member, and a positioning hole is provided on the first cathode placement groove and / or the second cathode placement groove, and the positioning block and the positioning hole can be aligned and engaged.

18. The wafer electroplating device according to claim 16, characterized in that: The crystal-carrying member is made of insulating material or the outer surface of the crystal-carrying member is covered with insulating material.

19. The wafer electroplating device according to claim 15, characterized in that: A pressure sensor is provided at the bottom of the placement groove near the wafer. Along the moving direction of the wafer in the placement groove, the orthographic projection of the periphery of the wafer on the bottom of the placement groove at least partially overlaps with the pressure sensor.

20. The wafer electroplating device according to claim 1, characterized in that The anode rack and cathode rack respectively include an anode alignment hole and a cathode alignment hole, wherein the anode alignment hole is used to expose the working surface of the anode component, and the cathode alignment hole is used to expose the surface to be plated of the wafer, and the shape and size of the anode alignment hole are comparable to those of the cathode alignment hole.

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