Flow assisted dynamic seal for high convection continuous rotary plating

Abstract

The invention discloses a flow assisted dynamic seal for high convection continuous spin plating. An apparatus for electroplating a semiconductor wafer includes an embedded member configured to surround a processing region. The insert member has a top surface. A portion of the top surface of the insert member has an upward slope that is inclined upward from a peripheral region of the top surface of the insert member toward the process region. The apparatus also includes a sealing member having a shape of an annular disc. The sealing member is positioned on the top surface of the insert member. The sealing member is flexible such that a radially outer portion of the sealing member is conformal with the upward ramp of the top surface of the insert member and such that a radially inner portion of the sealing member protrudes inward toward the treatment region.

Description

This application is a divisional application of the application with application number 201980015698.5, application date February 22, 2019, and invention name “Flow-assisted dynamic seal for high convection continuous rotary plating”. Technical Field

[0001] The present disclosure relates to the fabrication of semiconductor devices. Background Art

[0002] Some semiconductor device manufacturing processes involve electroplating materials onto semiconductor wafers. Electroplating can be accomplished in an electroplating bath, wherein a wafer (on which a conductive seed layer is present) is positioned so that the wafer is in physical contact with a plurality of electrical contacts. The surface of the wafer on which the seed layer is deposited is exposed to a bath of electroplating solution. An anode containing the metal to be plated on the wafer is placed within the bath of the electroplating solution. The anode is electrically connected to the positive terminal of a direct current (DC) power supply. The wafer is electrically connected to the negative terminal of the DC power supply via a plurality of electrical contacts. The DC power supply is operated to supply a DC current to the anode, which oxidizes the atoms of the anode and dissolves them in the bath of the electroplating solution. The wafer serves as the cathode of the electroplating bath, so that the negative charge on the wafer reduces the atoms released from the anode in the electroplating solution at the wafer surface, and causes atoms to be plated from the anode onto the wafer. The exposure of the wafer to the flow of the electroplating solution affects the exposure of the wafer to the atoms released from the anode within the electroplating solution, thereby affecting the atoms plated onto the wafer. The present disclosure was created in this context. Summary of the Invention

[0003] In an exemplary embodiment, an apparatus for electroplating semiconductor wafers is disclosed. The apparatus includes an embedded member configured to surround a processing area. The embedded member has a top surface. A portion of the top surface of the embedded member has an upward slope that slopes upward from a peripheral area of the top surface of the embedded member toward the processing area. The apparatus also includes a sealing member having the shape of an annular disk. The sealing member is positioned on the top surface of the embedded member. The sealing member is flexible so that a radially outer portion of the sealing member conforms to the upward slope of the top surface of the embedded member and a radially inner portion of the sealing member protrudes inward toward the processing area.

[0004] In one exemplary embodiment, a sealing device for electroplating equipment used in semiconductor wafer manufacturing is disclosed. The sealing device includes an annular disc-shaped structure configured to be mounted on the top surface of an embedded component of the electroplating equipment. The annular disc-shaped structure is flexible so as to physically conform to the contour of the top surface of the embedded component when mounted on the top surface of the embedded component, such that a radially outer portion of the annular disc-shaped structure conforms to the upward slope of the top surface of the embedded component and a radially inner portion of the annular disc-shaped structure protrudes inward from the top surface of the embedded component.

[0005] In one exemplary embodiment, a method for electroplating a semiconductor wafer is disclosed. The method includes providing an electroplating apparatus comprising an embedded member configured to surround a processing area. The embedded member has a top surface. A portion of the top surface of the embedded member has an upward slope that slopes upward from a peripheral area of the top surface of the embedded member toward the processing area. The electroplating apparatus further includes a sealing member having the shape of an annular disk. The sealing member is positioned on the top surface of the embedded member. The sealing member is flexible so that a radially outer portion of the sealing member conforms to the upward slope of the top surface of the embedded member and a radially inner portion of the sealing member protrudes toward the processing area. The electroplating apparatus further includes a cup-shaped member having an annular shape. The cup-shaped member has a bottom surface comprising a radially outer portion, the radially outer portion being configured to form a liquid seal with the top surface of the radially inner portion of the sealing member when the cup-shaped member is substantially centered above the sealing member and moves downward to contact the sealing member. The method further includes moving the cup-shaped member downward to form a liquid seal between the radially outer portion of the bottom surface of the cup-shaped member and the top surface of the radially inner portion of the sealing member. The method further includes flowing an electroplating solution through the treatment area. A portion of the electroplating solution flows over the bottom surface of the radially inner portion of the sealing member and presses the sealing member against the cup-shaped member to help maintain the liquid seal between the radially outer portion of the bottom surface of the cup-shaped member and the top surface of the radially inner portion of the sealing member.

[0006] In an exemplary embodiment, an embedded component of a sealing mechanism within an electroplating apparatus for semiconductor wafer manufacturing is disclosed. The embedded component includes a structural member configured to surround a processing area within the electroplating apparatus. The structural member has a top surface. A portion of the top surface of the structural member has an upward slope that slopes upward from a peripheral area of the top surface of the structural member toward the processing area. The top surface of the structural member is configured to receive and support a sealing member having an annular disk shape, wherein a radially inner portion of the sealing member protrudes inward toward the processing area. The structural member has sufficient rigidity so that when the radially inner portion of the sealing member is pushed downward, the radially outer portion of the sealing member conforms to the upward slope of the top surface of the embedded component. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1A A generalized view of a vertical cross-section of an electroplating apparatus for electroplating wafers is shown according to some embodiments.

[0008] Figure 1B According to some embodiments, Figure 1A , in which the conical member moves downwardly into engagement with the wafer to press the peripheral downwardly facing area of the wafer against the sealing surface of the lip seal member.

[0009] Figure 2A A top view of a finger contact is shown according to some embodiments.

[0010] Figure 2B A vertical cross-section through one of these finger contacts is shown according to some embodiments (eg, Figure 2A AA shown in ).

[0011] Figure 3 A vertical cross-section of a cup-shaped member positioned adjacent to an embedding member is shown according to some embodiments.

[0012] Figure 4 A vertical cross-section of a cup-shaped member positioned adjacent an insert member is shown, according to some embodiments, wherein a flow-assisted dynamic seal is configured to seal a gap between the cup-shaped member and the insert member.

[0013] Figure 5A A vertical cross-section of the interface between the cup-shaped member and the sealing member is shown when the radially outer portion of the bottom surface of the cup-shaped member is brought into contact with the radially inner portion of the sealing member, according to some embodiments.

[0014] Figure 5B According to some embodiments, as the cup-shaped member is further lowered relative to the insert member, Figure 5AA vertical cross-section of the interface between the cup-shaped member and the sealing member.

[0015] Figure 5C According to some embodiments, when the cup-shaped member is further lowered relative to the embedded member to the plating position Figure 5B A vertical cross-section of the interface between the cup-shaped member and the sealing member.

[0016] Figure 6 A top isometric view of an insert member is shown with a sealing member and a clamping ring mounted on the insert member, according to some embodiments.

[0017] Figure 7 Another top isometric view of an insert member is shown with a sealing member and a clamping ring mounted on the insert member, according to some embodiments.

[0018] Figure 8 A vertical cross-sectional view of a sealing member positioned to seal / close a gap between the cup-shaped member and the insert member when the cup-shaped member is lowered into the plating position is shown according to some embodiments.

[0019] Figure 9 A bottom isometric view of a cup-shaped member is shown according to some embodiments.

[0020] Figure 10A Another vertical cross-sectional view of a sealing member positioned to seal / close a gap between the cup-shaped member and the insert member when the cup-shaped member is lowered into the plating position is shown according to some embodiments.

[0021] Figure 10B A top isometric view of a sealing member is shown according to some embodiments.

[0022] Figure 11A According to some embodiments, a vertical cross-section of a cup member positioned adjacent an embedding member is shown, wherein a sealing member is configured to seal a gap between the cup member and the embedding member, and wherein a backing member is positioned below the sealing member.

[0023] Figure 11B A top isometric view of a backing member is shown according to some embodiments.

[0024] Figure 12 A flow chart is shown of a method for electroplating a semiconductor wafer, according to some embodiments. DETAILED DESCRIPTION

[0025] In the following description, numerous specific details are set forth to provide an understanding of the embodiments of the present invention. However, it will be apparent to one skilled in the art that the present disclosure may be practiced without some or all of these specific details. In other instances, well-known processing operations have not been described in detail in order to avoid unnecessarily obscuring the present disclosure.

[0026] Figure 1A A schematic diagram of a vertical cross-section of an electroplating apparatus 100 for electroplating a wafer 109 is shown according to some embodiments. In an exemplary embodiment, the term "wafer" as used herein refers to a semiconductor wafer. Furthermore, in various embodiments, the form, shape, and / or size of the wafers referred to herein may vary. For example, in some embodiments, the wafers referred to herein may correspond to a 200 mm (millimeter) semiconductor wafer, a 300 mm semiconductor wafer, or a 450 mm semiconductor wafer.

[0027] The electroplating apparatus 100 includes a cup-shaped member 101 and a cone-shaped member 103. The electroplating apparatus 100 also includes a lip seal member 105 configured to engage with the top of the cup-shaped member 101. A number of finger-shaped contact members 107 are disposed on the lip seal member 105. The finger-shaped contact members 107 are arranged in a circular configuration to provide substantially uniform support to the peripheral area of a wafer 109 to be processed.

[0028] Figure 2A A top view of the finger contacts 107 is shown according to some embodiments. Figure 2B A vertical cross-section through one of the finger contacts 107 is shown according to some embodiments (eg, Figure 2A AA). Figure 2A As shown, these finger contacts 107 are integrally connected to an annular conductive ribbon 107A (e.g., a metal ribbon). Both the finger contacts 107 and the conductive ribbon 107A are electrically conductive. It should be understood that in many embodiments, the finger contacts 107 and the conductive ribbon 107A can be formed of any conductive material that provides sufficient electrical conductivity for the performance of the electroplating process, has sufficient mechanical properties to support the wafer 109 during the electroplating process, and is chemically compatible with the environment and materials to which they are exposed during the electroplating process.

[0029] like Figure 2B and 1AAs shown, the finger contacts 107 are shaped to bend downward along the upper contour of the top of the lip seal member 105. Furthermore, the inner end sections 107B of the finger contacts 107 are bent upward relative to the circumferential configuration of the conductive tape 107A to provide support surfaces 107C for the wafer 109. Specifically, during the electroplating process, the wafer 109 is positioned on the support surfaces 107C of the finger contacts 107, wherein the surface of the wafer 109 to be plated faces downward toward the processing area 102 to physically contact the support surfaces 107C of the finger contacts 107.

[0030] The conical member 103 is attached to a shaft 111 that is configured to move upward and downward relative to the cup-shaped member 101, as indicated by arrow 111A. During the electroplating process, the conical member 103 is moved downward to engage the wafer 109 and press the wafer 109 onto the support surface 107C of the finger-shaped contact 107, so that the inner end section 107B of the finger-shaped contact 107 is bent downward toward the lip-shaped seal member 105 and the peripheral downward-facing area of the wafer 109 is pressed against the sealing surface 105A of the lip-shaped seal member 105. According to some embodiments, Figure 1B Shows Figure 1A , in which the conical member 103 moves downwardly into engagement with the wafer 109 (as indicated by arrow 111B) to press the peripheral downwardly facing area of the wafer 109 against the sealing surface 105A of the lip seal member 105. In the plating position, the cup member 101 is positioned adjacent the insert member 116 so that a gap 119 exists between the cup member 101 and the insert member 116 to enable the cup member 101 and the wafer 109 to rotate, as indicated by arrow 120.

[0031] A bath volume 113 for containing the electroplating solution is provided below the wafer 109. When the wafer 109 is pressed against the sealing surface 105A of the lip seal member 105 by the downward force exerted by the cone member 103, a seal is formed between the wafer 109 and the sealing surface 105A, so that the electroplating solution does not pass beyond the contact point between the wafer 109 and the sealing surface 105A of the lip seal member 105, thereby keeping the electroplating solution away from the finger contacts 107.

[0032] The electroplating apparatus 100 further includes a bus bar 115 configured to physically contact the conductive ribbon 107A, thereby establishing an electrical connection between the bus bar 115 and the finger contacts 107. The bus bar is formed of a solid metal member to improve azimuthal electroplating uniformity around the periphery of the wafer 109.

[0033] The bath volume 113 contains an anode member 117. In some embodiments, the anode member 117 is formed of copper. However, in other embodiments, the anode member 117 may be formed of other conductive materials suitable for the particular electroplating process being performed. In some embodiments, a membrane 118 is disposed within the bath volume 113 to physically separate the anode region below the membrane 118 from the cathode region above the membrane 118. The membrane 118 is configured to prevent bulk communication of the plating solution (electrolyte) between the anode region and the cathode region while allowing ions to communicate between the anode region and the cathode region. In some embodiments, the membrane 118 is an ion selective membrane. A channeled ion resistive plate (CIRP) 114 is positioned between the wafer 109 and the anode member 117. The CIRP 114 includes channels to allow the plating solution from the bath volume 113 to flow upward into the processing region 102 and to the surface of the wafer 109. These channels within the CIRP 114 are shown at Figure 6 middle.

[0034] During the electroplating process, the positive terminal of the DC power supply is electrically connected to the anode member 117, and the negative terminal of the DC power supply is electrically connected to the bus 115. In this manner, a current flow path is established from the anode member 117 through the electroplating solution to the surface of the wafer 109 exposed to the electroplating solution, from the surface of the wafer 109 to the finger contacts 107, and from the finger contacts 107 to the bus 115. Typically, prior to the electroplating process, a conductive seed layer is formed on the surface of the wafer 109 to be plated, thereby providing initial conductivity on the wafer 109. Then, as material is deposited / grown on the wafer 109 during the electroplating process, the deposited material causes conductivity on the wafer 109.

[0035] Figure 3 A vertical cross section of the cup member 101 is shown positioned adjacent to the insert member 116. The cup member 101 (which holds the wafer 109 face down) is positioned adjacent to but slightly above the top side of the insert member 116 to enable the cup member 101 and wafer 109 to rotate during plating. Figure 3In the configuration of , the gap 119 between the cup-shaped member 101 and the embedded member 116 is unsealed. The plating solution (supplied from below / inside the CIRP 114) is provided as a high-speed cross-flow between the CIRP 114 and the wafer 109 with the purpose of providing a fresh supply of plating solution deep into the features of the wafer. Due to the enormous pressure generated by the cross-flow of the plating solution, a portion of the flow leaks out of the gap 119 between the cup-shaped member 101 and the embedded member 116. This loss of plating solution reduces the amount and speed of the cross-flow of plating solution that contacts the surface of the wafer 109. Flow models have indicated that up to 30% of the cross-flow of plating solution may be lost through the gap 119 between the cup-shaped member 101 and the embedded member 116. This loss of plating solution reduces the supply of metal ions deep into the through-resist features, thereby reducing plating throughput and also degrading on-wafer performance. However, in Figure 3 In the configuration, a gap 119 is maintained between the cup-shaped member 101 and the embedding member 116 so that the cup-shaped member 101 (and the wafer 109 ) can rotate relative to the embedding member 116 .

[0036] Figure 3A modified form of the construction may include a rubber seal 121 (e.g., a Viton rubber seal) disposed between the cup-shaped member 101 and the embedded member 116 to reduce cross-flow leakage of the plating solution through the gap 119. In many embodiments, the rubber seal 121 may be attached to the top side of the cup-shaped member 101 or the embedded member 116. When the rubber seal 121 is tightly compressed between the cup-shaped member 101 and the embedded member 116, the cross-flow plating solution is prevented from leaking through the gap 119 around the cup-shaped member 101. However, there may be some limitations to how the rubber seal 121 may be used. For example, the rubber seal 121 may only be effective in preventing flow leakage of the plating solution when the rubber seal 121 is firmly compressed between the cup-shaped member 101 and the embedded member 116. In this firmly compressed state, the cup-shaped member 101 (and the wafer 109) cannot be rotated continuously relative to the insert member 116 during plating without damaging the cup-shaped member 101 and / or the rubber seal 121. Since plating without rotating the wafer 109 can result in significant feature tilt (poor within-feature (WiF) uniformity control) and possibly poor coplanarity / within-die (WiD) uniformity control (depending on the layout of the wafer 109), rotation of the wafer 109 may be necessary to achieve acceptable plating performance. Furthermore, the rubber seal 121 between the cup-shaped member 101 and the insert member 116 is a soft material that may have a short operating life under high friction conditions. Furthermore, the rubber seal 121 between the cup-shaped member 101 and the insert member 116 may be highly susceptible to failure due to aging / wear of the rubber seal 121 or improper placement. For example, as the rubber seal 121 becomes stretched, softened, and / or damaged due to aging / wear, the rubber seal 121 may no longer resist the flow / pressure of the electroplating solution even when compressed to an appropriate plating gap. The plating gap is the distance between the cup-shaped member 101 and the embedded member 116. Furthermore, if the plating gap is set too high, the rubber seal 121 may not be in firm contact with the cup-shaped member 101 and the embedded member 116 because the rubber seal 121 inherently has a small effective sealing range.

[0037] Figure 4A vertical cross-section of a cup-shaped member 401 (modified relative to cup-shaped member 101) positioned adjacent an insert member 403 (modified relative to insert member 116) is shown, according to some embodiments, wherein a flow-assist dynamic seal 405 is provided to seal a gap 407 between the cup-shaped member 401 and the insert member 403. The flow-assist dynamic seal 405 is hereinafter referred to as the sealing member 405. The sealing member 405 is a robust seal that eliminates cross-flow leakage of the plating solution through the gap 407 between the cup-shaped member 401 and the insert member 403 to maximize convection of the plating solution at the surface of the wafer 109, thereby enabling high-throughput plating and uniform deposition.

[0038] In some embodiments, the sealing member 405 has the shape of an annular disk. In these embodiments, when viewed from above or below, the sealing member 405 has a substantially annular shape defined by a uniform inner diameter and outer periphery. In some embodiments, the shape of the outer periphery of the sealing member 405 can vary with the azimuthal position around the outer periphery of the sealing member 405. For example, in some embodiments, the outer periphery of the sealing member 405 can include a plurality of spaced radially outward projections, with holes formed in these projections through the sealing member 405 for fastener insertion.

[0039] The sealing member 405 is positioned on the top surface of the insert member 403. The insert member 403 is configured to surround the processing region 102. A portion 403A of the top surface of the insert member 403 has an upward slope that slopes upward from a peripheral region 403B of the top surface of the insert member 403 toward the processing region 102 and reaches an apex 403C of the top surface of the insert member 403. The sealing member 405 is flexible so that a radially outer portion 405A of the sealing member 405 conforms to the upward slope of the portion 403A of the top surface of the insert member 403 and so that a radially inner portion 405B of the sealing member 405 protrudes inward toward the processing region 102.

[0040] In some embodiments, when the sealing member 405 is positioned on the top surface of the embed member 403, the radially inner portion 405B of the sealing member 405 protrudes toward the treatment region 102 at an upward angle relative to the horizontal plane. In some embodiments, the radially inner portion 405B of the sealing member 405 protrudes inwardly toward the treatment region 102 from the apex 403C of the top surface of the embed member 403. Furthermore, the radially inner portion 405B of the sealing member 405 is configured to bend downward relative to the apex 403C of the top surface of the embed member 403 when a downward force is applied to the top surface of the radially inner portion 405B of the sealing member 405.

[0041] The leakage path blocked by the sealing member 405 is the small but significant gap 407 between the cup-shaped member 401 (which holds the wafer 109 facing down toward the processing area 102) and the top side of the embedded member 403. The embedded member 403 is attached to the CIRP 114, which separates the wafer 109 from the anode 117. The sealing member 405 is attached to the top side of the embedded member 403 (as opposed to being attached to the cup-shaped member 401) using a clamping ring 409. The top side of the embedded member 403 is formed to slope upward toward the processing area 102, which forces the sealing member 405 to arc upward when the sealing member 405 is clamped down on the top side of the embedded member 403 by the clamping ring 409. In some embodiments, the clamping ring 409 is configured to hold the sealing member 405 on the top surface of the embedded member 403 at the following position: radially outward of the upward slope of the top surface of the embedded member 403. For example, at Figure 4 In the exemplary configuration of FIG, the retaining ring 409 is configured to retain the sealing member 405 on the top surface of the insert member 403 at a peripheral region 403B that is radially outward of the upward slope of a portion 403A of the top surface of the insert member 403. In some embodiments, the retaining ring 409 is bolted to the insert member 403 via the sealing member 405. However, it should be understood that in other embodiments, the retaining ring 409 may be secured to the insert member 403 in other ways (e.g., via an external C-clip or other locking / fastening device), so long as the retaining ring 409 serves to draw the sealing member 405 downward toward the top surface of the insert member 403 such that the sealing member 405 assumes a vertical cross-sectional shape that conforms to the contour of the top surface of the insert member 403.

[0042] The cup-shaped member 401 has an annular shape to surround the processing area 102. The cup-shaped member 401 has a bottom surface including a radially outer portion 411 that is configured to form a liquid seal with the top surface of the radially inner portion 405B of the sealing member 405 when the cup-shaped member 401 is substantially centered over the sealing member 405 and moves downward to contact the sealing member 405. In some embodiments, the radially outer portion 411 of the bottom surface of the cup-shaped member 401 is part of a recessed area formed at the bottom periphery of the cup-shaped member 401 to provide a location where the sealing member 405 can be pressed against the cup-shaped member 401 in a substantially uniform manner around the periphery of the cup-shaped member 401 to securely block the electroplating solution leakage path through the gap 407. In some embodiments, the radially outer portion 411 of the bottom surface of the cup-shaped member 401 has a substantially horizontal positioning when the cup-shaped member 401 is substantially centered over the sealing member 405 and moves downward to contact the sealing member 405. It should be understood that when the cup-shaped member 401 is lowered to the plating position, that is, when the cup-shaped member 401 is lowered relative to the insert member 403 to a position where the radially inner portion 405B of the sealing member 405 is contacted and pressed downward by the radially outer portion 411 of the bottom surface of the cup-shaped member 401, the top surface of the radially inner portion 405B of the sealing member 405 is firmly pressed against the radially outer portion 411 of the bottom surface of the cup-shaped member 401.

[0043] The tilted design of the top side of the insert member 403 is used to pre-load the sealing member 405 so that the radially inner portion 405B of the sealing member 405 is curved upward to contact the cup-shaped member 401 when the cup-shaped member 401 is lowered to the plating position. In some embodiments, the cup-shaped member 401 is configured to rotate relative to the sealing member 405 when the cup-shaped member 401 is substantially centered over the sealing member 405 and moves downward to contact the sealing member 405 so that the radially outer portion 411 of the bottom surface of the cup-shaped member 401 is configured to slide on the top surface of the radially inner portion 405B of the sealing member 405 while maintaining a liquid seal with the top surface of the radially inner portion 405B of the sealing member 405.

[0044] The sealing member 405 is made of a durable and low friction / slippery material to enable the cup member 401 to rotate relative to the sealing member 405. The cup member 401 can continuously rotate while in contact with the sealing member 405 to provide continuous (i.e., dynamic) rotation of the wafer 109 without damaging the sealing member 405 and / or the cup member 401, even when the cup member 401 / wafer 109 rotation rate is as high as 200 rpm (revolutions per minute). In some embodiments, the sealing member 405 is formed of polytetrafluoroethylene (PTFE). For example, in some embodiments, the sealing member 405 is formed of TEFLON TM , which is a form of PTFE. When the sealing member 405 is formed of PTFE, the top surface of the radially inner portion 405B of the sealing member 405 is durable and has a low coefficient of friction, so that the cup-shaped member 401 can rotate against the sealing member 405 without damaging the cup-shaped member 401 or the sealing member 405. In some embodiments, the sealing member 405 is formed of a material other than PTFE. For example, in some embodiments, the sealing member 405 is formed of a low-friction, highly wear-resistant polymer, such as, in particular, polyphenylene sulfide (PPS), polyetheretherketone (PEEK), polyamideimide (PAI), or ultra-high molecular weight polyethylene (UHMW).

[0045] In some embodiments, sealing member 405 can be formed from an elastomeric mixture, as long as sealing member 405 has sufficient durability and a low enough coefficient of friction to allow cup member 401 to rotate against sealing member 405 without damaging cup member 401 or sealing member 405. In some embodiments, sealing member 405 can be formed from an elastomeric mixture containing a low-friction additive that reduces the coefficient of friction of sealing member 405. For example, in some embodiments, the low-friction additive is one or more of polytetrafluoroethylene, molybdenum disulfide, and graphite. In some embodiments, sealing member 405 has a coefficient of friction of less than about 0.5. In some embodiments, the sealing member has a coefficient of friction of less than about 0.1.

[0046] Sealing member 405 is referred to as a "flow-assisted dynamic seal" because the pressure of the plating solution flow beneath cup-shaped member 401 serves to enhance the sealing ability of sealing member 405 by pressing radially inner portion 405B of sealing member 405 more firmly against cup-shaped member 401. It should be appreciated that, compared to the aforementioned rubber seal 121 disposed between cup-shaped member 101 and insert member 116 (which may leak when the plating solution flow pushes against rubber seal 121), the construction of sealing member 405 utilizes the pressure of the plating solution flow beneath cup-shaped member 401 to enhance the sealing ability of sealing member 405 by pressing radially inner portion 405B of sealing member 405 more firmly against radially outer portion 411 of the bottom surface of cup-shaped member 401. Furthermore, another advantage of sealing member 405 over rubber seal 121 is that sealing member 405 conforms to misalignment between cup-shaped member 401 and insert member 116. Compared to sealing member 405, rubber seal 121 has low compressibility and imperfect parallelism between cup member 401 and insert member 116, which results in varying compressibility and corresponding sealing performance along the sealing interface provided by rubber seal 121. Sealing member 405 provides much higher compressibility without applying significantly greater force relative to rubber seal 121. This means that the performance of sealing member 405 is maintained over a wider range of operating conditions.

[0047] The use of sealing member 405 provides optimal plating conditions by achieving the following: 1) a high degree of plating solution crossflow over the entire wafer 109 due to minimized plating solution flow leakage, and 2) continuous rotation of cup-shaped member 401 / wafer 109. These optimal plating conditions of minimized plating solution flow leakage and continuous cup-shaped member 401 / wafer 109 rotation together produce high wafer 109 processing throughput and excellent WiF and WiD. In addition, sealing member 405 is flexible and effective within a wide range of settings. That is, sealing member 405 has a large effective range. Specifically, even if the plating gap (the distance between cup-shaped member 401 and embedded member 403) changes within several millimeters, sealing member 405 can eliminate plating solution flow losses through gap 407. The large effective range of sealing member 405 is achieved through the flexibility of sealing member 405 and the preloaded, upwardly curved design. The large effective range of sealing member 405 can realize high process window and high error margin in hardware installation and setting reproducibility.The large effective range of sealing member 405 also can make the performance (for example, feature portion height distribution) of energy edge adjustment wafer 109 by deliberately changing plating gap.And, the plating gap adjustability (maintaining the sealing state between cup-shaped member 401 and embedded member 403 simultaneously) provided by sealing member 405 can handle multiple product types.Even under various loads and / or plating gap is provided height, sealing member 405 can effectively stop the electroplating solution flow loss by gap 407 in a wide range, it is owing to the flexibility of sealing member 405 and the upwards arc-shaped design of preload.

[0048] According to some embodiments, Figure 5A A vertical cross-section of the interface between the cup member 401 and the sealing member 405 is shown when the radially outer portion 411 of the bottom surface of the cup member 401 is in contact with the radially inner portion 405B of the sealing member 405 . Figure 5A The contact between the cup-shaped member 401 and the sealing member 405 may be sufficient to seal the gap 407 between the cup-shaped member 401 and the embedding member 403. According to some embodiments, Figure 5B Displayed in the following situations Figure 5A A vertical cross section of the interface between the cup-shaped member 401 and the sealing member 405: The cup-shaped member 401 is further lowered relative to the embedded member 403. When the sealing member 405 is pressed against the radially outer portion 411 of the bottom surface of the cup-shaped member 401, the sealing member 405 can bend to ensure a tight seal with the cup-shaped member 401. Figure 5B In the configuration of , the cup member 401 is in moderate contact with the sealing member 405. According to some embodiments, Figure 5C Displayed in the following situations Figure 5BA vertical cross-section of the interface between the cup-shaped member 401 and the sealing member 405: The cup-shaped member 401 is further lowered relative to the embedding member 403 to the plating position. In the plating position, the sealing member 405 presses on the radially outer portion 411 of the bottom surface of the cup-shaped member 401, and the sealing member 405 bends to contact the area within the radially outer portion 411 of the bottom surface of the cup-shaped member 401 to ensure a substantially liquid-tight seal with the cup-shaped member 401. Figure 5C In the structure of , the cup-shaped member 401 is in contact with the sealing member 405 over a large area.

[0049] Figure 6 A top isometric view of an insert member 403 is shown with a sealing member 405 and a clamping ring 409 mounted thereon, according to some embodiments. Figure 7 Another top isometric view of the insert member 403 is shown with the sealing member 405 and the clamping ring 409 mounted on the insert member 403, according to some embodiments.

[0050] Figure 8 A vertical cross-sectional view of a sealing member 405 is shown that is positioned to seal / close a gap 407 between the cup member 401 and the insert member 403 when the cup member 401 is lowered into the plating position, according to some embodiments. Figure 9 A bottom isometric view of a cup-shaped member 401 is shown according to some embodiments. A radially outer portion 411 of the bottom surface of the cup-shaped member 401 is shown at Figure 9 middle.

[0051] Figure 10A Another vertical cross-sectional view of a sealing member 405 is shown that is positioned to seal / close a gap 407 between the cup member 401 and the insert member 403 when the cup member 401 is lowered into the plating position, according to some embodiments. Figure 10B A top isometric view of a sealing member 405 is shown, according to some embodiments.

[0052] Figure 11A According to some embodiments, a vertical cross-section of a cup-shaped member 401 positioned adjacent to an insert member 403 is shown, wherein a sealing member 405 is positioned to seal a gap 407 between the cup-shaped member 401 and the insert member 403, and wherein a backing member 1101 is positioned below the sealing member 405. The backing member 1101 may also be referred to as a "reinforcement member." According to some embodiments, Figure 11BA top isometric view of backing member 1101 is shown. Backing member 1101 is positioned between sealing member 405 and the top surface of embedment member 403. Specifically, backing member 1101 is positioned between sealing member 405 and the top side of embedment member 403 and clamped to embedment member 403 using clamping ring 409, which simultaneously clamps sealing member 405 to embedment member 403. In some embodiments, backing member 1101 has a shape that is substantially the same as the annular disk shape of sealing member 405. In some embodiments, clamping ring 409 is configured to retain both sealing member 405 and backing member 1101 on the top surface of embedment member 403 at a location radially outward of an upward slope of the top surface of embedment member 403. In some embodiments, clamping ring 409 is bolted to the top surface of embedment member 403 via both sealing member 405 and backing member 1101.

[0053] Backing member 1101 is the supporting material of the backing (backing) that is arranged to sealing member 405 below, so that the pressure applied to cup-shaped member 401 by sealing member 405 increases, and is used to extend the operating life of sealing member 405. Backing member 1101 is arranged to: when downward force is applied to the top surface of the radially inner side portion 405B of sealing member 405, upward resistance force is applied by sealing member 405. And backing member 1101 is arranged to prevent electroplating solution from flowing on the bottom surface of the radially inner side portion 405B of sealing member 405. In some embodiments, backing member 1101 is formed by elastic stainless steel. However, in other embodiments, backing member 1101 can be formed by other materials that provide enough mechanical properties, chemical properties and thermal properties. Backing member 1101 can extend the operating life of sealing member 405 by reducing the sensitivity of sealing member 405 to wrinkles. The backing member 1101 can also serve as a support for the sealing member 405 if the sealing member 405 gradually creeps or deforms over time. When the backing member 1101 is formed from resilient stainless steel, or a similar material, the backing member 1101 can be heat treated to maintain its integrity and resist deformation.

[0054] It should be understood that the present invention discloses a sealing device for an electroplating apparatus for semiconductor wafer manufacturing. The sealing device includes a sealing member 405 defined as an annular disc-shaped structure, which is configured to be mounted on the top surface of an embedded member 403 of the electroplating apparatus. The annular disc-shaped structure (sealing member 405) has flexibility so that when the annular disc-shaped structure (sealing member 405) is mounted on the top surface of the embedded member 403, it physically conforms to the top surface contour of the embedded member 403, so that the radially outer portion 405A of the annular disc-shaped structure (sealing member 405) conforms to the upward slope of the top surface of the embedded member 403, and so that the radially inner portion 405B of the annular disc-shaped structure (sealing member 405) protrudes inwardly toward the processing area.

[0055] Figure 12 According to some embodiments, a flow chart of a method for electroplating a semiconductor wafer is shown. The method includes operation 1201, which is used to equip an electroplating apparatus, which includes an embedded component 403, which is configured to surround a processing area 102. The top surface of the embedded component 403 includes a portion 403A, which has an upward slope, which tilts upward from a peripheral area 403B on the top surface of the embedded component 403 toward the processing area 102. The electroplating apparatus also includes a sealing member 405 having an annular disk shape. The sealing member 405 is positioned on the top surface of the embedded component 403. The sealing member 405 is flexible, so that the radially outer portion 405A of the sealing member 405 is conformal to the upward slope of the top surface of the embedded component 403, and so that the radially inner portion 405B of the sealing member 405 protrudes toward the processing area 102. The electroplating apparatus also includes a cup-shaped member 401, which has an annular shape. Cup member 401 has a bottom surface including a radially outer portion 411 that is configured to form a liquid seal with a top surface of radially inner portion 405B of sealing member 405 when cup member 401 is substantially centered over sealing member 405 and moves downward to contact sealing member 405 .

[0056] The method further includes operation 1203 for moving the cup-shaped member 401 downward to form a liquid seal between the radially outer portion 411 of the bottom surface of the cup-shaped member 401 and the top surface of the radially inner portion 405B of the sealing member 405. The method further includes operation 1205 for flowing the electroplating solution through the processing area 102. In operation 1205, a portion of the electroplating solution flows over the bottom surface of the radially inner portion 405B of the sealing member 405 and presses the sealing member 405 against the cup-shaped member 401 to help maintain the liquid seal between the radially outer portion 411 of the bottom surface of the cup-shaped member 401 and the top surface of the radially inner portion 405B of the sealing member 405. The method also includes operation 1207, which is used to rotate the cup-shaped member 401 relative to both the embedded member 403 and the sealing member 405 so that the radially outer portion 411 of the bottom surface of the cup-shaped member 401 slides on the top surface of the radially inner portion 405B of the sealing member 405, and at the same time maintain a liquid seal between the radially outer portion 411 of the bottom surface of the cup-shaped member 401 and the top surface of the radially inner portion 405B of the sealing member 405.

[0057] It should be understood that the sealing member 405 disclosed herein, together with the cup-shaped member 401 and the insert member 403, reduces and / or prevents leakage of the plating solution through the gap 407 between the cup-shaped member 401 and the insert member 403, and thus provides a modified plating solution crossflow and a modified plating solution convection in the features on the wafer 109. The modified plating solution crossflow and convection correspond to modified plating performance on the wafer 109, such as modified WiF uniformity and reduced skirting. The modified plating solution convection also enables better ion transport to the bottom of the features on the wafer 109, which can lead to higher plating rates and improved overall wafer 109 manufacturing throughput.

[0058] The above-described embodiments are provided for illustration and description purposes. They are not intended to be exhaustive or to limit the present disclosure. Even if not specifically shown or described, individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but are interchangeable and applicable to the selected embodiment where applicable. They may also be varied in many ways. Such variations are not considered to depart from the present disclosure, and all such modifications are intended to be included within the scope of the present disclosure.

[0059] Although the foregoing disclosure has been described in some detail for purposes of clarity of understanding, it will be apparent that certain changes and modifications may be practiced within the scope of the embodiments disclosed herein. The present embodiments are therefore to be considered as illustrative and not restrictive, and the disclosure is not to be limited to the details provided herein, but may be modified within the scope of equivalents of the embodiments.

Claims

1. A backing member for an electroplating apparatus for semiconductor wafer manufacturing, comprising: A structural member configured to provide lower support for a sealing member, the structural member configured to be mounted on a top surface of an embedded member, the embedded member configured to surround a processing area, the structural member configured to apply an upward resistance force through the sealing member when a downward force is applied to the top surface of a radially inner portion of the sealing member, wherein the embedded member has an annular disk shape, wherein the top surface of the embedded member has an upward slope that slopes upward from a peripheral area of the top surface of the embedded member toward an inner edge of the top surface of the embedded member, wherein the structural member is configured to conform to the upward slope of the top surface of the embedded member under an elastic force.

2. The backing member of the electroplating apparatus for semiconductor wafer manufacturing according to claim 1, wherein the structural member has an annular disk-shaped structure that is substantially identical to the annular disk-shaped structure of the sealing member. 3 . The backing member of an electroplating apparatus for semiconductor wafer manufacturing according to claim 1 , wherein the structural member is configured to prevent the electroplating solution from flowing on the bottom surface of the sealing member.

4. The backing member of an electroplating apparatus for semiconductor wafer manufacturing according to claim 1, wherein the structural member is formed of elastic stainless steel.

5. The backing member of an electroplating apparatus for semiconductor wafer manufacturing according to claim 1, wherein the structural member is fixed to a clamping ring configured to hold the sealing member and the structural component.

6. The backing member of an electroplating apparatus for semiconductor wafer manufacturing according to claim 1, wherein the structural member is formed of a flexible elastic material.

7. The backing member of an electroplating apparatus for semiconductor wafer manufacturing according to claim 6, wherein a radially inner portion of the structural member is flexible relative to a radially outer portion of the structural member.

8. A backing member for an electroplating apparatus for semiconductor wafer fabrication as claimed in claim 1, wherein the structural member is configured to apply an upward resistance through the sealing member so as to form a liquid-tight seal between the sealing member and a cup-shaped member in contact with the sealing component.

9. The backing member of an electroplating apparatus for semiconductor wafer manufacturing according to claim 1, wherein the radially outer portion of the structural member is configured to be fixed in a clamping manner between a top surface of the embedded member and a clamping ring.

10. The backing member of an electroplating apparatus for semiconductor wafer fabrication as claimed in claim 9, wherein the radially outer portion of the structural member comprises a plurality of holes through which a corresponding plurality of pins are provided for securing the clamping ring to the embedded member.

11. The backing member for electroplating equipment for semiconductor wafer manufacturing according to claim 1, wherein When the structural member is positioned on the top surface of the embedment member, the radially inner portion of the structural component protrudes toward the treatment area at an upward angle relative to a horizontal plane.

12. A backing member for an electroplating device for semiconductor wafer manufacturing as described in claim 1, wherein the radially inner portion of the structural member protrudes inwardly from the apex of the top surface of the embedded member toward the processing area, and wherein the radially inner portion of the structural member is configured to bend downward around the apex of the top surface of the embedded member when the downward force is applied to the top surface of the radially inner portion of the sealing member.

13. The backing member of an electroplating apparatus for semiconductor wafer fabrication as claimed in claim 1, wherein the structural member forms a support for the sealing member.

14. The backing member for electroplating equipment for semiconductor wafer fabrication as claimed in claim 1, wherein the structural member is heat treated to maintain integrity and resist deformation.

15. A sealing system for electroplating equipment used in semiconductor wafer manufacturing, comprising: a sealing member having an annular structure configured to be mounted on a top surface of an embedding member of the electroplating apparatus, the sealing member having a radially outer portion contacting the top surface of the embedding member, the sealing member being flexible so as to physically conform to a contour of the top surface of the embedding member such that when the sealing member is mounted on the top surface of the embedding member, the radially outer portion of the sealing member conforms to an upward slope of the top surface of the embedding member, the sealing member having a radially inner portion protruding inwardly from an apex of the top surface of the embedding member; as well as A backing member having the same shape as the sealing member is configured to be disposed between the sealing member and the top surface of the embedding member.

16. The sealing system of claim 15, wherein the backing member is configured to exert upward resistance through the sealing element when downward pressure is applied to the top surface of the radially inner portion of the sealing member.

17. The sealing system of claim 15, wherein the backing member is configured to prevent a plating solution from flowing on a bottom surface of the radially inner portion of the sealing member.

18. The sealing system of claim 15, wherein the backing member is formed of stainless steel.

19. The sealing system of claim 15, wherein the backing member forms a support for the sealing member.

20. The sealing system of claim 15, wherein the backing member is heat treated to maintain integrity and resist deformation.

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