Electroplating device

Abstract

The embodiment of the utility model discloses an electroplating device which comprises an electroplating cavity used for containing electroplating liquid; the magnetizing device is used for providing a magnetic field and magnetizing the electroplating liquid; the magnetizing device comprises a first conductive coil surrounding the outer side wall of the electroplating cavity; the bearing head is used for bearing a wafer; the bearing head comprises a cathode, and the cathode is connected with the wafer; and the anode is positioned in the electroplating cavity and is in contact with the electroplating liquid in the electroplating cavity.

Description

Technical Field

[0001] This disclosure relates to the field of semiconductor technology, and more particularly to an electroplating apparatus. Background Technology

[0002] In semiconductor manufacturing, electroplating uses wafers as the substrate to form metal layers or metal wires in specific areas to achieve specific circuit functions. Additionally, in some packaging processes, electroplating can be used to form copper pillars and solder bumps on the wafer to achieve interconnection between the chip and the substrate. In wafer electroplating, the wafer can be connected to a cathode. During electroplating, the wafer is immersed in the electroplating solution, with the soluble or insoluble anode located below the wafer. Under the influence of an electric field, metal ions in the electroplating solution are deposited onto the wafer surface to form the electroplated layer. As the integration density of semiconductor processes increases, the sizes of openings, apertures, and grooves that require electroplating are becoming smaller, and the depth of structures requiring electroplating is becoming deeper. Because the electroplating solution cannot make good contact with the bottom of the structure to be filled, voids and defects are formed after electroplating, reducing manufacturing yield. Therefore, there is still much room for improvement in electroplating processes and equipment. Utility Model Content

[0003] According to some aspects of embodiments of the present disclosure, an electroplating apparatus is provided, comprising: an electroplating chamber for holding an electroplating solution; a magnetizing device for providing a magnetic field and magnetizing the electroplating solution; and a carrier head for carrying a wafer; the magnetizing device comprising: a first conductive coil surrounding an outer wall of the electroplating chamber;

[0004] The carrier head includes a cathode connected to the wafer and an anode located in the electroplating chamber and in contact with the electroplating solution in the electroplating chamber.

[0005] In some embodiments, the electroplating apparatus further includes: a reflux chamber, sleeved outside the electroplating chamber; the reflux chamber is in communication with the electroplating chamber, and the first conductive coil is located in the reflux chamber.

[0006] In some embodiments, the electroplating apparatus further includes: a return port located at the bottom of the return cavity; the top of the return port is connected to the return cavity, and the bottom of the return port is connected to a return pipe; the top of the return port is higher than the first conductive coil.

[0007] In some embodiments, the electroplating apparatus includes: an annular cover located above the sidewall of the reflux chamber; the opening end of the annular cover exposes the electroplating chamber; wherein the diameter of the opening end of the annular cover is greater than the diameter of the electroplating chamber; and the diameter of the opening end of the annular cover is less than the diameter of the bottom of the annular cover.

[0008] In some embodiments, the support head includes: a support platform for supporting the wafer; a limiting ring, the inner ring of which is used to fix the wafer; the limiting ring has a boss at one end facing the electroplating cavity, the boss is located in the inner ring of the limiting ring, and the boss protrudes from the inner sidewall of the limiting ring along the horizontal side; wherein the support platform and the limiting ring move relative to each other in the vertical direction, so that the edge of the wafer abuts against the boss.

[0009] In some embodiments, the electroplating apparatus further includes: a power supply, the positive terminal of which is connected to the anode; a cathode provided by the limiting ring, the negative terminal of which is connected to the limiting ring; and / or, the cathode provided by the support stage, the contact surface of which the support stage contacts the wafer being connected to the negative terminal of the power supply.

[0010] In some embodiments, the electroplating apparatus further includes: a diffusion plate having a plurality of through holes; the diffusion plate being located in the electroplating chamber and above the anode; and an ion exchange membrane being located in the electroplating chamber and between the diffusion plate and the anode.

[0011] In some embodiments, the electroplating apparatus further includes: a liquid inlet located at the bottom of the electroplating chamber; the liquid inlet communicating with the electroplating chamber; a liquid supply device for storing the electroplating solution; and a liquid delivery pipe, at least partially used to connect the liquid supply device and the liquid inlet; the liquid delivery pipe for transporting the electroplating solution.

[0012] In some embodiments, the magnetization device includes a second conductive coil surrounding the outer wall of the infusion tubing.

[0013] In some embodiments, the magnetization device includes a magnetic pole located in the liquid supply device.

[0014] This disclosure provides an electroplating apparatus, including an electroplating chamber for holding an electroplating solution; a magnetization device for providing a magnetic field and magnetizing the electroplating solution; a carrier head for carrying or clamping a wafer, the carrier head including a cathode connected to the wafer; and an anode located in the electroplating chamber and in contact with the electroplating solution in the electroplating chamber. The carrier head fixes and carries the wafer so that the surface of the wafer to be plated comes into contact with the electroplating solution. Under the action of the electric field, metal ions in the electroplating solution gain electrons on the wafer surface and are reduced to metal, depositing a metal coating on the wafer surface. The magnetic field magnetizes the electroplating solution to reduce the surface tension of the electroplating solution, improve the wettability of the electroplating solution to the wafer surface, and reduce void defects in the electroplated film layer. Attached Figure Description

[0015] Figure 1 and Figure 2 This is a schematic diagram of electroplating according to an exemplary embodiment;

[0016] Figure 3 This is a schematic diagram illustrating the surface tension test of an electroplating solution according to an exemplary embodiment;

[0017] Figures 4 to 11 This is a schematic diagram of an electroplating apparatus according to an embodiment of the present disclosure;

[0018] Figure 12 and Figure 13 This is a schematic diagram of a magnetization device according to an embodiment of the present disclosure. Detailed Implementation

[0019] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the specific embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0020] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that "some embodiments" or "an embodiment" as used throughout the specification means that a particular feature, structure, or characteristic related to an embodiment is included in at least one embodiment of this disclosure. Therefore, "some embodiments" or "an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. Furthermore, these particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0021] According to some aspects of exemplary embodiments of this disclosure, electroplating apparatus adapted to wafer surface electroplating processes may include, but is not limited to, vertical immersion electroplating apparatuses and horizontal wafer electroplating apparatuses. In a vertical immersion electroplating process, one or more wafers can be vertically immersed in a water tank containing the electroplating solution to complete wafer electroplating. This process is adaptable to double-sided plating on both the back and front sides of the wafer and to the simultaneous electroplating of multiple batches of wafers.

[0022] In the wafer horizontal electroplating process, the surface of the wafer to be plated, such as the front side of the wafer, is placed horizontally and brought into contact with the electroplating solution to complete the film plating. The back side of the wafer does not need to come into contact with the electroplating solution, thereby reducing the contamination or other interference of the back side metal layer on subsequent processes. Electroplating apparatus used in wafer horizontal electroplating processes may include, but is not limited to, cup-type electroplating apparatuses. A cup-type electroplating apparatus may at least include an electroplating chamber containing an electroplating solution. A soluble or insoluble anode may be disposed within the electroplating chamber. The anode is connected to the positive terminal of a power supply and can be immersed in the electroplating solution for electrical connection. A clamp is disposed above the electroplating chamber in the vertical direction or the wafer thickness direction. The wafer is placed horizontally on the clamp. The clamp holds, adsorbs, or otherwise fixes the edge of the wafer. The clamp as a whole may serve as a cathode, or the clamp may include a cathode in contact with the wafer, which is connected to the negative terminal of the power supply. The clamp holds the wafer and moves it downwards toward the electroplating solution to immerse it in the electroplating solution to complete the electroplating. For example, a seed layer, such as a copper or cobalt layer, may be formed above the surface of the wafer, and a metal plating layer may be formed by electroplating on the seed layer.

[0023] In some embodiments, Figure 1 An example of a structure to be filled in the surface of wafer 100 with electroplating solution is shown. (Refer to...) Figure 1 As illustrated in Part a, the structure to be filled on the surface of wafer 100 may include, but is not limited to, openings, and grooves; taking opening 201 as an example, there are no specific limitations on the shape and size of opening 201, and the sidewalls and / or bottom of opening 201 may include dielectric material, and may include conductive material; when the surface tension of electroplating solution 202 is high, there may be a situation where electroplating solution 202 cannot fill the bottom of opening 201, resulting in Figure 1 The electroplated layer 203 formed in part b cannot completely fill the opening 201, resulting in void defects. In some specific embodiments, the large surface tension of the electroplating solution causes the bubbles generated during the electroplating process to not be discharged in time, resulting in them being buried in the plating layer or directly causing local areas to not contact the plating solution, forming voids on the plating surface.

[0024] In some embodiments, surfactants or other organic solvents can be added to the electroplating solution to reduce its surface tension. However, excessive addition of additives can introduce impurities into the solution, potentially contaminating the plating layer or reducing the concentration of metal ions, leading to plating defects. In some embodiments, a magnetic field is used to magnetize the electroplating solution, thereby reducing its surface tension. For example, under the influence of a magnetic field, the chemical bonds in water molecules within the electroplating solution undergo changes in angle and length, such as a decrease in hydrogen bond angle, resulting in a reduction in the surface tension of the electroplating solution. Figure 2 As shown in part a, the low surface tension electroplating solution 202 can fill the openings well. Figure 2The electroplated layer 203 formed in part b can fill the openings well.

[0025] In some embodiments, Figure 3 The change in contact angle before and after magnetization of the electroplating solution is shown. The contact angle between the electroplating solution and the test surface before magnetization is α1, and the contact angle after magnetization is α2, where α2 is less than α1. The decrease in contact angle indicates an improvement in the wettability of the electroplating solution on the test surface, and a decrease in the surface tension of the electroplating solution. The test surface may include, but is not limited to, a copper layer. In some other embodiments, adjusting parameters such as the strength of the magnetic field, the duration of the magnetic field magnetization, and the concentration and flow rate of the electroplating solution can reduce the surface tension of the electroplating solution by 10% to 25%. The magnetization treatment duration may include, but is not limited to, 1 minute to 1 hour.

[0026] In some embodiments, a magnetic field can be generated using an energized coil and magnetic poles to magnetize the electroplating solution, thereby reducing the surface tension of the electroplating solution. The magnetic poles may include magnetic materials. The electroplating solution contained in the electroplating chamber can be magnetized, the electroplating solution in the electroplating solution storage tank can be magnetized, and the electroplating solution in the electroplating solution delivery pipeline can be magnetized.

[0027] According to some aspects of embodiments of this disclosure, Figure 4 An electroplating apparatus 10 is provided, comprising at least: an electroplating chamber 101 for holding an electroplating solution; and a magnetizing device for providing a magnetic field and magnetizing the electroplating solution. The magnetizing device includes: a first conductive coil 111 surrounding the outer wall of the electroplating chamber 101; a carrier head 130 for carrying a wafer 100; the carrier head 130 includes a cathode connected to the wafer 100; and an anode 121 located in the electroplating chamber 101 and in contact with the electroplating solution in the electroplating chamber 101. The magnetizing device may include, but is not limited to, the first conductive coil 111 wound around the outer wall of the electroplating chamber 101, or a magnetic pole 113 located outside the electroplating chamber 101. A portion of the carrier head 130 is connected to the negative terminal of a power supply to serve as a cathode, which is then connected to the wafer 100 to provide a negative voltage.

[0028] In the accompanying drawings of this embodiment, the z-direction is a vertical direction, which can be the thickness direction of the wafer 100 or a first direction. The x-direction can be a horizontal direction perpendicular to the z-direction or a second direction. The y-direction can be a horizontal direction perpendicular to the x-direction or a third direction. In some embodiments, the electroplating apparatus 10 can be an electroplating machine, electroplating equipment, or an electroplating system, or at least a part of an electroplating machine, equipment, or system, and there are no limitations on this.

[0029] The electroplating apparatus 10 also includes a power supply, a robotic arm, a control unit, and a cleaning tank. The power supply is configured to power various components of the electroplating apparatus 10, including DC and AC power outputs in various voltage ranges. The control unit is connected to the robotic arm, which controls the robotic arm to pick up wafers 100 from components such as wafer cassettes, wafer storage stages, wafer boats, or cleaning baskets. The control unit controls the robotic arm to place the wafers 100 onto the carrier head 130 and controls the carrier head 130 to carry and fix the wafers 100. The fixing method may include, but is not limited to, clamping, electrostatic adsorption, or vacuum adsorption, exposing the surface of the wafers 100 to be electroplated. The carrier head 130 may include a cathode, which is directly connected to the wafers 100 or connected via conductive components such as contacts, bumps, conductive wires, and conductive connectors, providing a negative potential to the wafers 100. The negative terminal of the power supply is connected to the cathode, and the positive terminal is connected to the anode 121. The power supply voltage range can be adjusted according to process requirements. In other embodiments, the power supply has multiple interfaces or multiple voltage generation modules. Some of the interfaces or voltage generation modules of the power supply provide a negative terminal and a positive terminal. The negative terminal is connected to the cathode to provide a negative potential to the wafer 100; the positive terminal is connected to the anode 121.

[0030] The sidewalls of the electroplating chamber 101 may include polymeric materials, such as polytetrafluoroethylene (PTFE), to reduce corrosion; alternatively, the sidewalls may include metallic materials with an anti-corrosion coating, such as a polymeric coating like PTFE. The anode 121 may be made of soluble or insoluble materials. During electroplating of the wafer 100, the anode 121 may undergo a reduction reaction and dissolve to replenish metal ions in the electroplating solution. The anode 121 may be a replaceable consumable. The anode 121 may be located in any area inside the electroplating chamber 101 and in contact with the electroplating solution. For example, the anode 121 may be located at the bottom of the electroplating chamber 101 and may be submerged in the electroplating solution. The electroplating chamber 101 may have mounting holes for fixing the anode 121, with fixing methods including but not limited to clamps and threaded connections; the anode 121 may be disassembled and replaced. One end of the anode 121 can be exposed from the bottom of the electroplating chamber 101 and connected to the positive terminal of the power supply, or a wire can be connected to the anode 121 from the mounting hole at the bottom of the electroplating chamber 101.

[0031] In some embodiments, refer to Figure 4 As shown, the carrier head 130 may include a carrier stage 131 and a limiting ring 132. The wafer 100 can be horizontally placed between the limiting ring 132 and the carrier stage 131. The carrier stage 131 and the limiting ring 132 move relative to each other in the z-direction to clamp the wafer 100 and fix it. The carrier head 130 may be a pressure plate, and the limiting ring 132 may be a cup-shaped assembly or a clamp. The carrier head 130 is located above the electroplating chamber 101 in the z-direction. The electroplating chamber 101 can hold electroplating solution, which may overflow the electroplating chamber 101 or not. Figure 4 The electroplating chamber 101 may be an example where no electroplating solution is introduced. The dimension in the x direction of the end of the limiting ring 132 facing or near the electroplating chamber 101 in the z direction may be smaller than the dimension of the other end of the limiting ring 132. Alternatively, the diameter and width of the end of the limiting ring 132 facing the electroplating chamber 101 in the z direction may be smaller than the dimension of the other end. The limiting ring is conical. The support stage 131 and the limiting ring 132 move closer to each other to perform a clamping action. The wafer 100 can be fixed against the end of the limiting ring 132 near the electroplating chamber 101. At this time, the limiting ring 132 is sleeved around the support stage 131. The edge of the wafer 100 is clamped and fixed by the support stage 131 and the limiting ring 132. The surface of the wafer 100 to be electroplated (e.g., the front side) is exposed from the middle area of ​​the limiting ring 132. At least a part of the back side of the wafer 100 is covered by the support stage 131 and is not exposed, reducing the coating on the back side of the wafer 100. The carrier stage 131 moves downwards, carrying the wafer 100 with its surface to be electroplated into the electroplating solution for electroplating. The carrier stage 131 may include a rotating component, which is powered by a motor to rotate the carrier stage 131, such as clockwise or counterclockwise on a horizontal plane, to ensure that the electroplating solution fully contacts the surface of the wafer 100. After electroplating, the carrier stage 131 carries the wafer 100 upwards away from the electroplating chamber 101. The carrier stage 131 may rotate to dry the electroplating solution on the surface of the wafer 100. The carrier stage 131 and the limiting ring 132 move away from each other, releasing their clamping grip, and the robotic arm removes the wafer 100. The robotic arm can pick up the wafer 100 from the carrier head 130 and place it into a cleaning tank for cleaning to reduce electroplating solution residue on the surface of the wafer 100. The cleaning tank may contain cleaning solution, including but not limited to high-purity water.

[0032] In some embodiments, refer to Figure 4 As shown, the limiting ring 132 has an annular boss 133 at one end in the z-direction near the electroplating cavity 101. The boss 133 is located in the inner ring of the limiting ring 132 and protrudes from the inner sidewall of the limiting ring 132 in the x-direction. The boss 133 is used to abut against, support, and fix the edge of the wafer 100 to prevent the wafer 100 from sliding. The limiting ring 132 can serve as a cathode, and the boss 133 can serve as the contact point between the cathode and the wafer 100, providing a negative potential to the wafer 100. The support stage 131 and the limiting ring 132 can move relative to each other in the z-direction. When they are close to each other, they clamp and fix the wafer 100, and when they are far apart, they loosen the clamping. For example, the limiting ring 132 does not move up and down, while the support stage 131 moves up and down; or, the support stage 131 does not move up and down, while the limiting ring 132 moves up and down.

[0033] In some embodiments, refer to Figure 4 and Figure 5As shown, the magnetization device includes: a first conductive coil 111, which surrounds or winds around the outer wall of the electroplating cavity 101; or, it includes a magnetic pole 113 located outside the electroplating cavity 101. The first conductive coil 111 can be wound around the outer wall of the electroplating cavity 101, and can be wound clockwise or counterclockwise. The number of turns or loops can be adapted according to the height of the electroplating cavity 101 and the required magnetic field strength. Figure 4 The first conductive coil 111 shown is a continuously wound coil. On the left side of the electroplating cavity 101, the coil extends outward along the vertical x direction, i.e., along the negative y direction; on the right side of the electroplating cavity 101, the coil extends inward along the vertical x direction, i.e., along the positive y direction. Figure 4 The first conductive coil 111 is wound counterclockwise in the xoy plane. The winding area of ​​the first conductive coil 111 in the electroplating cavity 101 can be located in the central region of the sidewall of the electroplating cavity 101, or relatively close to one end of the sidewall in the z-direction, or it can wind around the entire sidewall of the electroplating cavity 101. For example, the first conductive coil 111 can start winding from the bottom of the electroplating cavity 101, winding around the central region of the electroplating cavity 101, with the first conductive coil 111 below the opening end of the electroplating cavity 101 by a certain distance and not flush with the opening end of the electroplating cavity 101, and may not wind around the top region of the electroplating cavity 101. The first conductive coil 111 is a wire with an insulating outer sheath and a conductive inner core; both ends of the first conductive coil 111 are connected to a circuit for power supply. By adjusting the current to a minimum and the energizing time of the first conductive coil 111, the strength of the generated magnetic field and the magnetization treatment time can be controlled, thereby magnetizing the electroplating solution to reduce the surface tension of the electroplating solution. For example, the magnetic flux density of the magnetic field may include, but is not limited to, 0.001-100T (Tesla, T), and the processing time may be 1 minute to 1 hour.

[0034] In other embodiments, reference is made to Figure 5 As shown, a magnetic pole 113 can be disposed outside the electroplating chamber 101, and the magnetic pole 113 can be disposed on the outer wall of the electroplating chamber 101; the magnetic pole 113 can be an annular magnetic pole 113, sleeved on the outer wall of the electroplating chamber 101. In some other embodiments, the magnetic pole 113 can be disposed inside the electroplating chamber 101, such as on the inner wall of the electroplating chamber 101. The outer surface of the magnetic pole 113 can be coated with an anti-corrosion coating, such as, but not limited to, rubber, polytetrafluoroethylene, etc., to reduce the corrosion of the magnetic pole 113 by the electroplating solution. For example, the material of the magnetic pole 113 can include, but is not limited to, magnetic materials such as neodymium iron boron, ferrite, AlNiCo, or Samarium Cobalt.

[0035] In some embodiments, refer to Figure 6 As shown, the bearing head 130 includes:

[0036] A support platform 131 is used to support the wafer 100; a limiting ring 132, the inner ring of which is used to fix the wafer 100; the end of the limiting ring 132 facing the electroplating cavity 101 has a boss 133, the boss 133 is located in the inner ring of the limiting ring 132, and the boss 133 protrudes from the inner sidewall of the limiting ring 132 along the horizontal side; wherein, the support platform 131 and the limiting ring 132 move relative to each other in the vertical direction, so that the edge of the wafer 100 abuts against the boss 133. The wafer 100 is placed between the support platform 131 and the limiting ring 132, and the relative movement between the support platform 131 and the limiting ring 132 includes at least one component of the support platform 131 and the limiting ring 132 being able to move up and down in the z direction, so that the support platform 131 and the limiting ring 132 move closer to each other to clamp the wafer 100; the support platform 131 and the limiting ring 132 move further apart to release the clamping.

[0037] like Figure 6 As shown, the carrier head 130 is located above the electroplating cavity 101. The carrier head 130 can rotate around the horizontal axis, allowing its two sides in the z-direction to face the electroplating cavity 101 at different times. When preparing to receive or output the wafer 100, the carrier head 130 rotates to position the carrier stage 131 below the limiting ring 132. The limiting ring 132 rises, and the robotic arm places the wafer 100 along its side onto the carrier stage 131. The limiting ring 132 descends, and the boss 133 contacts and abuts against the edge of the wafer 100, clamping the wafer 100 in conjunction with the carrier stage 131. At this time, the non-electroplated surface of the wafer 100, such as the back of the wafer 100, is in contact with and covered by the carrier stage 131. The boss 133 can be a continuous, annular structure, such as a continuous circumferential protrusion on the inner wall of the limiting ring 132. Figure 7 As exemplified; or the boss 133 is a protrusion or a bump, and multiple bosses 133 are distributed at intervals on the inner wall of the limiting ring 132, such as 3 or 4 bosses 133 being distributed at intervals in a circle on the inner wall of the limiting ring 132, and being at or substantially at the same horizontal height.

[0038] After the wafer 100 is clamped, the carrier head 130 is flipped, as follows. Figure 4 The example support stage 131 is positioned above the wafer 100, and the support head 130 descends to immerse the front side of the wafer 100 in the electroplating solution for electroplating. The limiting ring 132 can be... Figure 6The push rod 134 (or push pin) in the middle moves up and down, and the movement of the push rod 134 drives the limit ring 132 to move up and down. The carrier stage 131 can rotate clockwise or counterclockwise on the horizontal plane to ensure that the electroplating solution can fully contact the surface of the wafer 100. After electroplating, the carrier stage 131 carries the wafer 100 upward and moves away from the electroplating chamber 101. The carrier stage 131 can rotate to dry the electroplating solution on the surface of the wafer 100. After the wafer 100 is electroplated, the carrier head 130 flips back to its original position. Figure 6 At the position shown, the push rod 134 rises, causing the limiting ring 132 to rise. The limiting ring 132 no longer holds the wafer 100, and the robotic arm picks up the wafer 100 from the carrier platform 131 for the next manufacturing step.

[0039] In some embodiments, the electroplating apparatus 10 further includes: a power supply, the positive terminal of which is connected to the anode 121; a cathode provided by a limiting ring 132, the negative terminal of which is connected to the limiting ring 132; and / or, a cathode provided by a support stage 131, the contact surface of which the support stage 131 contacts the wafer 100 being connected to the negative terminal of the power supply. Alternatively, the cathode may include at least one of the support stage 131 and the limiting ring 132.

[0040] Reference Figure 4 and Figure 5 As shown, the support stage 131, or at least the surface of the support stage 131 that contacts the wafer 100, is connected to the negative terminal of the power supply, serving as the cathode. The surface of the support stage 131 that contacts the wafer 100 is made of a conductive material. Conductive wires are provided inside the support stage 131, connecting the negative terminal of the power supply and the contact surface of the support stage 131 and the wafer 100. The contact surface of the support stage 131 serves as the cathode.

[0041] In some specific embodiments, at least a portion of the limiting ring 132 serves as a cathode and is connected to the negative terminal of the power supply; for example, the limiting ring 132 as a whole is made of conductive material and serves as a cathode connected to the negative terminal of the power supply; or, Figure 4 and Figure 5 In addition to the contact portion between the boss 133 of the limiting ring 132 and the wafer 100, the non-contact portions of the limiting ring 132 and the wafer 100, such as the outer wall of the limiting ring 132, can be coated with a polymer coating such as rubber or polytetrafluoroethylene to reduce corrosion and leakage of the limiting ring 132. Conductive contacts and bumps can be provided on the contact portion between the boss 133 and the wafer 100 to reduce contact resistance. In some specific embodiments, the limiting ring 132 is made of insulating materials such as polymers or ceramics to reduce corrosion and the formation of plating on the limiting ring 132; conductive contacts and bumps can be provided on the contact portion between the boss 133 and the wafer 100, and conductive wires are provided inside the limiting ring 132 to connect to the negative terminal of the power supply and the contacts on the boss 133 that contact the wafer 100. The limiting ring 132 and the support platform 131 can simultaneously serve as cathodes.

[0042] In some embodiments, Figure 7 , Figures 8 to 10 A three-dimensional schematic diagram of the limiting ring 132 and a portion of the electroplating chamber 101 at different angles is provided; see reference. Figures 7 to 10 As shown, the electroplating apparatus 10 further includes: a reflux chamber 102, which is sleeved outside the electroplating chamber 101; the reflux chamber 102 is connected to the electroplating chamber 101, and the first conductive coil 111 is located in the reflux chamber 102.

[0043] The electroplating apparatus 10 can have a double-chamber structure for holding or containing the electroplating solution, such as an electroplating chamber 101 and a reflux chamber 102. The electroplating chamber 101 is aligned with or corresponds to the wafer 100 to serve as the operating chamber for the electroplating process, and is housed within the reflux chamber 102. The bottom of the reflux chamber 102 can be fixedly connected to and sealed with the bottom of the electroplating chamber 101. There is a gap between the sidewall of the reflux chamber 102 and the sidewall of the electroplating chamber 101, which communicates with the opening of the electroplating chamber 101. After the electroplating solution overflows from the electroplating chamber 101, it can flow into the reflux chamber 102. The reflux chamber 102 can be connected to a pipeline to discharge the electroplating solution to a waste liquid collection device or to the electroplating solution supply device 16 for electroplating solution circulation. Alternatively, as shown below, Figure 7 As exemplified, the cavity structure of the electroplating apparatus 10 may include two sleeved annular sidewalls and a sealing plate located at the bottom of the annular sidewalls, thereby forming two chambers: an electroplating chamber 101 in the inner ring and a reflux chamber 102 in the outer ring. The electroplating chamber 101 may be provided with an inlet for introducing electroplating solution, and the reflux chamber 102 may be provided with a return port 13 or a drain port for discharging electroplating solution, thereby enabling the replacement or circulation of the electroplating solution.

[0044] The first conductive coil 111 is located in the reflux cavity 102, between the side wall of the electroplating cavity 101 and the side wall of the reflux cavity 102. The electroplating solution overflows from the electroplating cavity 101 and flows into the reflux cavity 102, contacting the first conductive coil 111 and cooling it. When the electroplating solution is discharged from the reflux cavity 102, it carries away the heat from the first conductive coil 111, thus improving cooling performance. The external covering material of the first conductive coil 111 can be a polymer insulating material, similar to the material of the wall of the electroplating cavity 101, such as polytetrafluoroethylene (PTFE), to reduce corrosion and provide insulation.

[0045] In some embodiments, refer to Figure 9 As shown, the electroplating apparatus 10 also includes:

[0046] The return port 13 is located at the bottom of the return cavity 102; the top of the return port 13 is connected to the return cavity 102, and the bottom of the return port 13 can be connected to the return pipe; the top of the return port 13 is higher than the first conductive coil 111. The return port 13 can be used to connect the return cavity 102 and the return pipe to discharge the electroplating solution in the return cavity 102, thereby realizing the replacement or circulation of the electroplating solution.

[0047] The return port 13 can be located at the bottom of the return cavity 102. The return port 13 can be a tubular channel extending along the z-direction, protruding from the bottom of the return cavity 102. When the electroplating solution overflows from the electroplating cavity 101 and flows into the return cavity 102, the electroplating solution flows out from the return port 13 when the electroplating solution level in the return cavity 102 is higher than the top of the return port 13. The horizontal height of the top of the return port 13 is lower than the horizontal height of the top of the electroplating cavity 101. The first conductive coil 111 can be wound from the bottom of the return cavity 102 to the top of the electroplating cavity 101 to surround the side wall of the electroplating cavity 101. The horizontal height of the first conductive coil 111 in the z-direction, or the horizontal height of the topmost coil of the first conductive coil 111, is lower than the horizontal height of the top of the return port 13, which allows the electroplating solution flowing into the return cavity 102 to immerse the first conductive coil 111, improving the heat dissipation of the first conductive coil 111.

[0048] In some embodiments, refer to 7 to Figure 10 As shown, the electroplating apparatus 10 includes:

[0049] An annular cover 141 is located on the outer wall of the reflux cavity 102; the opening end of the annular cover 141 exposes the electroplating cavity 101; wherein, the diameter of the opening end of the annular cover 141 is greater than the diameter of the electroplating cavity 101; the diameter of the opening end of the annular cover 141 is less than the diameter of the bottom of the annular cover 141. Figure 9As shown, the bottom of the annular cover 141 is aligned and looped with the outer wall of the reflux chamber 102. The fixing method may include, but is not limited to, clamps, flanges, welding, etc. The annular cover 141 and the reflux chamber 102 are detachably connected; for example, the annular cover 141 can be fitted onto the outer wall of the reflux chamber 102 and secured using clips or bolts. The annular cover 141 can be a variable-diameter flared structure or a conical truncated cone structure. The limiting ring 132 and the support stage 131 clamp the wafer 100 and move it downwards, passing through the opening end of the annular cover 141 until it reaches the electroplating chamber 101, so that the surface of the wafer 100 to be electroplated is immersed in the electroplating solution. The dimension of the opening end of the annular cover 141 in the x direction is also the diameter and width dimension. The diameter and width dimension of the opening end of the annular cover 141 can be larger than the diameter and width dimension of the opening end of the electroplating chamber 101. The diameter and width dimension of the opening end of the annular cover 141 can be larger than the diameter and width dimension of the limiting ring 132, so as to facilitate the alignment of the wafer 100 and the electroplating chamber 101 and reduce the collision between the limiting ring 132 and the annular cover 141. The diameter and width dimension of the opening end of the annular cover 141 can be smaller than the diameter and width dimension of the bottom of the annular cover 141 to reduce the splashing of the electroplating solution. After the wafer 100 is electroplated, the carrier head 130 is raised to move the wafer 100 away from the electroplating liquid surface and rotates and spins the wafer 100 within the space of the annular cover 141. The annular cover 141 can surround the wafer 100 to reduce the splashing of the electroplating liquid.

[0050] In some embodiments, refer to Figures 4 to 6 ,as well as Figure 11 As shown, the electroplating apparatus 10 further includes: a diffusion plate 122, including multiple through holes 12; the diffusion plate 122 is located in the electroplating chamber 101 and above the anode 121; and an ion exchange membrane 123 is located in the electroplating chamber 101 and between the diffusion plate 122 and the anode 121. In the electroplating chamber 101, from the bottom to the opening end of the electroplating chamber 101, the following components are arranged in sequence: anode 121, ion exchange membrane 123, diffusion plate 122, and support head 130, which may or may not support the wafer 100.

[0051] The diffuser plate 122 may include through holes 12 for the passage and dispersion of the electroplating solution. The through holes 12 of the diffuser plate 122 may be as follows: Figures 7 to 10The arrangement can be a concentric circle array or a polygonal array; the diffuser plate 122 is removable and replaceable. In some embodiments, the current density distribution on the wafer 100 is uneven, such as a higher current density at the edges of the wafer 100. This unevenness results in a higher plating rate at the edges of the wafer 100 and a lower plating rate at the center of the wafer 100, leading to uneven coating. The flow distribution of the plating solution on the surface of the wafer 100 can be adjusted by setting the diameter and distribution density of the vias 12 in different regions of the diffuser plate 122. For example, the diameter of the vias 12 on the surface of the diffuser plate 122 decreases from the center to the edge, or the distribution density of the vias 12 decreases from the center to the edge, thereby increasing the flow of the plating solution in the central region of the wafer 100 and strengthening the central electric field, making the thickness distribution of the plating layer on the entire wafer 100 more uniform.

[0052] In some embodiments, such as Figures 4 to 6 As shown, the electroplating apparatus 10 may further include a support 124 for mounting the ion exchange membrane 123. The portion of the support 124 extending along the x-direction is annular, with a hollowed-out central region. The ion exchange membrane 123 is mounted on the annular portion of the support 124, exposing the ion exchange membrane 123 in the central region of the annular portion. The ion exchange membrane 123 can be mounted on either the upper or lower surface of the annular portion of the support 124. The support 124 can also be used to support and mount the diffuser plate 122.

[0053] In some embodiments, the ion exchange membrane 123 can divide the electroplating chamber 101 into a cathode region and an anode region, with the cathode region above the ion exchange membrane 123 and the anode region below it. The ion exchange membrane 123 can allow the metal ions to be plated in the anode region to pass through to replenish the concentration of the metal ions to be plated in the cathode region, and prevent some components, such as electrons or other byproducts, from being released from the cathode region into the anode region.

[0054] In some embodiments, refer to Figure 11 As shown, the electroplating apparatus 10 further includes: a liquid inlet 11 located at the bottom of the electroplating chamber 101; the liquid inlet 11 is connected to the electroplating chamber 101; a liquid supply device 16 for storing electroplating solution; and a liquid delivery pipe 15, at least partially used to connect the liquid supply device 16 and the liquid inlet 11; the liquid delivery pipe 15 is used to transport the electroplating solution.

[0055] like Figure 11In the example shown, a branch of the infusion pipeline 15 serves as a supply pipeline, connecting to the inlet 11 at the bottom of the electroplating chamber 101 and the interface of the supply device 16. This connection can be achieved via threaded connection or welding. A circulation pump 17 and a filter 18 can be connected between the supply device 16 and the inlet 11. The electroplating solution from the supply device 16, after being pressurized by the circulation pump 17 and filtered by the filter 18, is fed into the inlet 11 of the electroplating chamber 101, providing electroplating solution to the electroplating chamber 101. A branch of the infusion pipeline 15 serves as a return pipeline, connecting to the return port 13 of the return chamber 102. The electroplating solution in the return chamber 102 flows into the supply device 16 through the return port 13 to complete the circulation of the electroplating solution. The supply device 16 may include a storage tank, a storage vessel, etc., and may include multiple interfaces to connect to various pipelines. Valves can be installed at these interfaces to control their opening and closing.

[0056] In some embodiments, such as Figure 12 As shown, the magnetization device may include a magnetic pole 113 located in the liquid supply device 16. The magnetic pole 113 may be provided in the liquid supply device 16 to magnetize the electroplating solution in the liquid supply device 16; or an energized coil may be provided wound around the outer wall of the liquid storage tank or liquid storage trough to magnetize the electroplating solution.

[0057] In some embodiments, refer to Figure 13 As shown, the magnetization device includes a second conductive coil 112, which surrounds the outer wall of the infusion pipe 15. Figure 13 As shown, the flow direction of the electroplating solution in the infusion pipe 15 can be indicated by the arrow in the figure. The second conductive coil 112 is wound around the outer wall of the infusion pipe 15. When the second conductive coil 112 is energized, it generates a magnetic field to magnetize the electroplating solution in the infusion pipe 15 and reduce the surface tension of the electroplating solution. Figure 13 The infusion pipeline 15 shown can be part or all of the circulation pipeline of the electroplating device 10. For example, it can be the infusion pipeline connecting the inlet 11 of the electroplating chamber 101 and the infusion supply device 16, or the return pipeline connecting the return port 13 of the return chamber 102 and the infusion supply device 16.

[0058] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure.

Claims

1. An electroplating apparatus, characterized in that, include: Electroplating chamber, used to hold electroplating solution; A magnetization device for providing a magnetic field and magnetizing the electroplating solution; The magnetization device includes: a first conductive coil surrounding the outer wall of the electroplating chamber; A carrier head for carrying a wafer; the carrier head includes a cathode connected to the wafer. The anode is located in the electroplating chamber and is in contact with the electroplating solution in the electroplating chamber.

2. The electroplating apparatus according to claim 1, characterized in that, The electroplating apparatus also includes: A reflux cavity is fitted outside the electroplating cavity; the reflux cavity is connected to the electroplating cavity, and the first conductive coil is located in the reflux cavity.

3. The electroplating apparatus according to claim 2, characterized in that, The electroplating apparatus further includes: The return port is located at the bottom of the return cavity; the top of the return port is connected to the return cavity, and the bottom of the return port is connected to the return pipe; the top of the return port is higher than the first conductive coil.

4. The electroplating apparatus according to claim 2, characterized in that, The electroplating apparatus further includes: An annular cover is located on the side wall of the reflux chamber; the opening end of the annular cover exposes the electroplating chamber; wherein the diameter of the opening end of the annular cover is greater than the diameter of the electroplating chamber; and the diameter of the opening end of the annular cover is less than the diameter of the bottom of the annular cover.

5. The electroplating apparatus according to claim 1, characterized in that, The bearing head includes: A support platform for supporting the wafer; A limiting ring, the inner ring of which is used to fix the wafer; the end of the limiting ring facing the electroplating cavity has a boss, the boss is located in the inner ring of the limiting ring, and the boss protrudes from the inner sidewall of the limiting ring along the horizontal side; The support platform and the limiting ring move relative to each other in the vertical direction, so that the edge of the wafer abuts against the boss.

6. The electroplating apparatus according to claim 5, characterized in that, The electroplating apparatus also includes: A power source, wherein the positive terminal of the power source is connected to the anode; The cathode is provided by the limiting ring, and the negative terminal of the power supply is connected to the limiting ring; And / or, the cathode is provided by the carrier stage, and the contact surface of the carrier stage that contacts the wafer is connected to the negative terminal of the power supply.

7. The electroplating apparatus according to claim 1, characterized in that, The electroplating apparatus also includes: A diffusion plate includes multiple through holes; the diffusion plate is located in the electroplating chamber and above the anode; An ion exchange membrane is located in the electroplating chamber and between the diffuser plate and the anode.

8. The electroplating apparatus according to claim 1, characterized in that, The electroplating apparatus also includes: The liquid inlet is located at the bottom of the electroplating chamber; the liquid inlet is connected to the electroplating chamber. A liquid supply device for storing the electroplating solution; The infusion pipeline is at least partially used to connect the liquid supply device and the liquid inlet; the infusion pipeline is used to transport the electroplating solution.

9. The electroplating apparatus according to claim 8, characterized in that, The magnetization device includes: A second conductive coil surrounds the outer wall of the infusion tubing.

10. The electroplating apparatus according to claim 8, characterized in that, The magnetization device includes: The magnetic poles are located in the liquid supply device.

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