Flow-assisted dynamic seals for high convection continuous spin plating

Abstract

An apparatus for electroplating semiconductor wafers 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 an annular disk shape. 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 inwardly toward the processing area.

Description

Technical Field

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

[0002] Some semiconductor device manufacturing processes include electroplating materials onto semiconductor wafers. Electroplating can be accomplished in an electroplating bath, wherein the wafer (on which there is a conductive seed layer) 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 an electroplating solution. An anode containing the metal to be plated on the wafer is disposed 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 through a plurality of electrical contacts. The DC power supply is operated to supply a DC current to the anode, which oxidizes and dissolves the atoms of the anode 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 present in the electroplating solution at the surface of the wafer, and causes the 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 in the electroplating solution, thereby affecting the atoms plated on 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 an exemplary embodiment, a sealing device for an electroplating device for 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 device. The annular disc-shaped structure has flexibility to physically conform to the contour of the top surface of the embedded component when the annular disc-shaped structure is mounted on the top surface of the embedded component, so that the radially outer side of the annular disc-shaped structure conforms to the upward slope of the top surface of the embedded component, and the radially inner side of the annular disc-shaped structure protrudes inward from the top surface of the embedded component.

[0005] In an exemplary embodiment, a method for electroplating a semiconductor wafer is disclosed. The method includes: an electroplating apparatus equipped with 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 also includes a sealing member having an annular disk shape. The sealing member is positioned on the top surface of the embedded member. The sealing member is flexible so that the radially outer portion of the sealing member conforms to the upward slope of the top surface of the embedded member and the radially inner portion of the sealing member protrudes toward the processing area. The electroplating apparatus also includes a cup-shaped member having an annular shape. The cup-shaped member has a bottom surface including a radially outer portion, and the radially outer portion is 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 assist in maintaining 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.

[0006] In an exemplary embodiment, an embedded component of a sealing mechanism in an electroplating device for semiconductor wafer manufacturing is disclosed. The embedded component includes a structural member configured to surround a processing area in the electroplating device. The structural member has a top surface. A portion of the top surface of the structural member has an upward slope, and the upward slope is inclined 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 the radial inner side of the sealing member protrudes inward toward the processing area. The structural member has sufficient rigidity so that when the radial inner side of the sealing member is pushed downward, the radial outer side of the sealing member conforms to the upward slope of the top surface of the embedded member. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0008] Figure 1BAccording 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-shaped sealing member.

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

[0010] Figure 2B A vertical cross-sectional view through one of the 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 to an embedding 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 embedding member.

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

[0014] Figure 5B According to some embodiments, when the cup-shaped member is further lowered relative to the embedding member, Figure 5A A 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 retaining 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 retaining 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 a cup-shaped member and an embedded member when the cup-shaped member is lowered into a plating position is shown according to some embodiments.

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

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

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

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

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

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

[0025] In the following description, a large number of specific details are described to provide an understanding of the embodiments of the present invention. However, it will be apparent to those skilled in the art that the present disclosure can be practiced without some or all of these specific details. In other cases, well-known processing operations are not described in detail in order to avoid unnecessarily obscuring the present disclosure.

[0026] Figure 1A A generalized view 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. Also, in various embodiments, the form, shape, and / or size of the wafers mentioned herein may be different. For example, in some embodiments, the wafers mentioned 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 contacts 107 are disposed on the lip seal member 105. The finger contacts 107 are arranged in a circular configuration to provide substantially uniform support for the peripheral area of ​​a wafer 109 to be processed.

[0028] Figure 2A A top view of a finger contact 107 is shown according to some embodiments. Figure 2B A vertical cross-sectional view 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 strip 107A (e.g., a metal strip). Both the finger contacts 107 and the conductive strip 107A are electrically conductive. It should be understood that in many embodiments, the finger contacts 107 and the conductive strip 107A can be formed of any conductive material that provides sufficient electrical conductance 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 it is exposed during the electroplating process.

[0029] like Figure 2B and 1A As shown, the finger contact 107 is formed to bend downward along the upper contour of the top of the lip seal member 105. Also, the inner end section 107B of the finger contact 107 is bent upward relative to the circumferential configuration of the conductive tape 107A to provide a support surface 107C for the wafer 109. Specifically, during the electroplating process, the wafer 109 is positioned on the support surface 107C of the finger contact 107, wherein the surface of the wafer 109 to be electroplated is facing downward toward the processing area 102 to physically contact the support surface 107C of the finger contact 107.

[0030] The cone-shaped member 103 is attached to the shaft 111, which is configured to move upward and downward relative to the cup-shaped member 101, as indicated by arrow 111A. During the electroplating process, the cone-shaped member 103 is moved downward to engage with 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 sealing member 105 and the peripheral downward-facing area of ​​the wafer 109 is pressed against the sealing surface 105A of the lip-shaped sealing member 105. According to some embodiments, Figure 1B Shows Figure 1A , wherein the conical member 103 moves downwardly to engage 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 electroplating position, the cup member 101 is positioned adjacent to the embedded member 116 so that a gap 119 exists between the cup member 101 and the embedded 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 accommodating 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 applied by the conical member 103, a seal is formed between the wafer 109 and the sealing surface 105A, so that the electroplating solution does not pass the contact position 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 piece for improving azimuthal electroplating uniformity near the periphery of the wafer 109.

[0033] The bath volume 113 includes 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 specific 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 avoid 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 in 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 the material is deposited / grown on the wafer 109 during the electroplating process, the deposited material causes conductivity on the wafer 109.

[0035] Figure 3A 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 allow the cup member 101 and wafer 109 to rotate during plating. Figure 3 In the configuration of , the gap 119 between the cup-shaped member 101 and the embedded member 116 is unsealed. The plating solution (provided from below / inside the CIRP 114) is provided as a high-speed cross-flow between the CIRP 114 and the wafer 109 for 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 velocity 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 structure of FIG. 1 , a gap 119 is maintained between the cup-shaped member 101 and the embedded member 116 so that the cup-shaped member 101 (and the wafer 109 ) can rotate relative to the embedded 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 out through the gap 119 around the cup-shaped member 101. However, there may be some limitations to the method of using the rubber seal 121. For example, the rubber seal 121 may be effective in preventing flow leakage of the plating solution only 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 in a continuous manner relative to the embedded member 116 during plating without damaging the cup-shaped member 101 and / or the rubber seal 121. Since plating without rotating the wafer 109 may result in significant feature tilt (poor feature-within (WiF) uniformity control) and may also result in poor coplanarity / within-die (WiD) uniformity control (depending on the layout of the wafer 109), rotation of the wafer 109 may be necessary to obtain acceptable plating performance. Also, the rubber seal 121 between the cup-shaped member 101 and the embedded member 116 is a soft material that may have a short operating life under high friction conditions. In addition, the rubber seal 121 between the cup-shaped member 101 and the embedded member 116 may be highly susceptible to failure caused by aging / wear or improper placement of the rubber seal 121. 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. Also, 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 member 401 (modified relative to cup member 101) positioned adjacent to an insert member 403 (modified relative to insert member 116) is shown according to some embodiments, wherein a flow-assisted dynamic seal 405 is disposed to seal a gap 407 between the cup member 401 and the insert member 403. The flow-assisted 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 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, which is 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 some spaced radially outward convex portions, in which holes through the sealing member 405 are formed for fastener embedding.

[0039] The sealing member 405 is positioned on the top surface of the embedding member 403. The embedding member 403 is configured to surround the processing region 102. A portion 403A of the top surface of the embedding member 403 has an upward slope that slopes upward from a peripheral region 403B of the top surface of the embedding member 403 toward the processing region 102 and reaches an apex 403C of the top surface of the embedding 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 embedding 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 embedding member 403, the radially inner portion 405B of the sealing member 405 protrudes toward the processing 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 processing region 102 from the vertex 403C of the top surface of the embedding member 403. And, the radially inner portion 405B of the sealing member 405 is configured to bend downward relative to the vertex 403C of the top surface of the embedding 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 downward 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 downward 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 outside the upward slope of the top surface of the embedded member 403. For example, at Figure 4 In the exemplary configuration of FIG. 4 , the clamping ring 409 is configured to retain the sealing member 405 on the top surface of the embedding member 403 at a peripheral region 403B that is radially outward of the upward slope of the portion 403A of the top surface of the embedding member 403. In some embodiments, the clamping ring 409 is bolted to the embedding member 403 via the sealing member 405. However, it should be understood that in other embodiments, the clamping ring 409 may be secured to the embedding member 403 in other ways (e.g., by an external C-clip or other locking / fastening device), as long as the clamping ring 409 is used to pull the sealing member 405 downward toward the top surface of the embedding member 403 so that the sealing member 405 presents a vertical cross-sectional shape that conforms to the contour of the top surface of the embedding 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, which 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 a portion of a recessed area formed at the bottom periphery of the cup-shaped member 401 to provide a position 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 firmly block the plating 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 embedded member 403 to a certain position (at this position, 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 on the radially outer portion 411 of the bottom surface of the cup-shaped member 401.

[0043] The inclination of the top side of the embedded member 403 is designed 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 above 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 allow 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., in a dynamic manner) 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 rotates at rates up to 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 made of TEFLON TM The sealing member 405 is made of PTFE, 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 friction coefficient, so the cup-shaped member 401 can be rotated 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, high-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, the sealing member 405 can be formed of an elastomeric mixture, as long as the sealing member 405 has sufficient durability and a low enough coefficient of friction to allow the cup-shaped member 401 to 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 can be formed of an elastomeric mixture containing a low-friction additive that reduces the coefficient of friction of the 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, the sealing member 405 has a coefficient of friction less than about 0.5. In some embodiments, the sealing member has a coefficient of friction less than about 0.1.

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

[0047] The use of sealing member 405 provides the best plating conditions by achieving the following: 1) high degree of plating solution cross flow caused by minimized plating solution flow leakage over the whole wafer 109, and 2) continuous rotation of cup-shaped member 401 / wafer 109. These best plating conditions of minimized plating solution flow leakage and continuous cup-shaped member 401 / wafer 109 rotation together produce high wafer 109 processing capacity and excellent WiF and WiD. And, sealing member 405 is flexible and effective in 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 in several millimeters, sealing member 405 can also eliminate the plating solution flow loss through gap 407. The large effective range of sealing member 405 is realized by the flexibility of sealing member 405 and the preloaded, upwardly curved design. The large effective range of the sealing member 405 can achieve high process window and high error margin in hardware installation and setting reproducibility. The large effective range of the sealing member 405 can also make it possible to adjust the performance (e.g., feature height distribution) of the wafer 109 by deliberately changing the plating gap. And, the plating gap adjustability provided by the sealing member 405 (while maintaining the sealing state between the cup-shaped member 401 and the embedded member 403) can handle a variety of product types. Even under various loads and / or plating gap setting heights, the sealing member 405 can effectively prevent the loss of the electroplating solution flow through the gap 407 in a wide range, which is attributed to the flexibility of the sealing member 405 and the preloaded upwardly curved design.

[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 in the embodiment may be sufficient to seal the gap 407 between the cup-shaped member 401 and the embedded 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 on 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, the cup-shaped 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 embedded 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 wide area.

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

[0050] Figure 8 A vertical cross-sectional view of a sealing member 405 is shown according to some embodiments, the sealing member 405 being positioned to seal / close a gap 407 between the cup member 401 and the embedding member 403 when the cup member 401 is lowered into the plating position. Fig. 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 Fig. 9 middle.

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

[0052] Fig.11A According to some embodiments, a vertical cross-section of a cup-shaped member 401 positioned near an embedding member 403 is shown, wherein a sealing member 405 is configured to seal a gap 407 between the cup-shaped member 401 and the embedding 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, Fig. 11BA top isometric view of a backing member 1101 is shown. The backing member 1101 is disposed between the sealing member 405 and the top surface of the embedding member 403. Specifically, the backing member 1101 is positioned between the sealing member 405 and the top side of the embedding member 403 and is clamped to the embedding member 403 using a clamping ring 409 while the sealing member 405 is clamped to the embedding member 403. In some embodiments, the backing member 1101 has a substantially identical shape to the annular disk shape of the sealing member 405. In some embodiments, the clamping ring 409 is configured to hold both the sealing member 405 and the backing member 1101 on the top surface of the embedding member 403 at a location radially outward of an upward slope of the top surface of the embedding member 403. In some embodiments, the clamping ring 409 is bolted to the top surface of the embedding member 403 by both the sealing member 405 and the backing member 1101.

[0053] Backing member 1101 is a supporting material that is arranged as the backing (backing) below sealing member 405, 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 radial inner side portion 405B of sealing member 405, upward resistance is applied by sealing member 405. And, backing member 1101 is arranged to prevent electroplating solution from flowing on the bottom surface of radial 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 may also serve as a support for the sealing member 405 should the sealing member 405 gradually creep or deform over time. When the backing member 1101 is formed of resilient stainless steel, or a similar material, the backing member 1101 may 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 device 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 device. The annular disc-shaped structure (sealing member 405) has flexibility to physically conform to the top surface contour of the embedded member 403 when the annular disc-shaped structure (sealing member 405) is mounted on the top surface of the embedded member 403, so that the radially outer side 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 side 405B of the annular disc-shaped structure (sealing member 405) protrudes inwardly toward the processing area.

[0055] Fig.12 A flow chart of a method for electroplating a semiconductor wafer is shown according to some embodiments. The method includes operation 1201, which is used to equip an electroplating device, which includes an embedded member 403, and the embedded member 403 is configured to surround the processing area 102. The top surface of the embedded member 403 includes a portion 403A, and the portion 403A has an upward slope, which is tilted upward from the peripheral area 403B of the top surface of the embedded member 403 toward the processing area 102. The electroplating device also includes a sealing member 405, which has the shape of an annular disk. The sealing member 405 is positioned on the top surface of the embedded member 403. The sealing member 405 is flexible, so that the radially outer side portion 405A of the sealing member 405 is conformal with the upward slope of the top surface of the embedded member 403, and so that the radially inner side portion 405B of the sealing member 405 protrudes toward the processing area 102. The electroplating device 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 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 an 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 an operation 1205 for flowing the electroplating solution through the processing area 102. In operation 1205, a portion of the electroplating solution flows on 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 member 401 and the embedded member 403, reduces and / or prevents leakage of the plating solution through the gap 407 between the cup member 401 and the embedded member 403, and thus provides a modified plating solution cross flow and a modified plating solution convection in the features on the wafer 109. The modified plating solution cross flow 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 contribute to higher plating rates and improve the manufacturing yield of the overall wafer 109.

[0058] The above-mentioned embodiment description is provided for the purpose of illustration and description. It is not intended to be exhaustive or limit the present disclosure. Even if not specifically shown or described, the individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but are all interchangeable and can be used for the selected embodiment where applicable. It can also be changed in many ways. Such changes are not considered to depart from the present disclosure, and all such modifications should be included in the scope of the present disclosure.

[0059] Although the foregoing disclosure has been described in considerable detail for the purpose of clarity of understanding, it is apparent that certain changes and modifications may be implemented within the scope of the embodiments disclosed herein. Therefore, the present embodiments should be considered illustrative rather than restrictive, and the disclosure should not be limited to the details provided herein, but may be modified within the scope of equivalents of the embodiments.

Claims

1. An apparatus for electroplating a semiconductor wafer, comprising: an embedding member configured to surround a processing area, the embedding member having a top surface, a portion of the top surface of the embedding member having an upward slope that slopes upward from a peripheral area of ​​the top surface of the embedding member toward the processing area; and A sealing member having the shape of an annular disk is positioned on the top surface of the embedded member, and the sealing member is flexible so that the radial outer portion of the sealing member is conformal to the upward slope of the top surface of the embedded member and the radial inner portion of the sealing member protrudes inwardly toward the treatment area.

2. The device according to claim 1, wherein: When the sealing member is positioned on the top surface of the embedding member, the radially inner portion of the sealing member protrudes toward the treatment area at an upward angle relative to a horizontal plane.

3. The device according to claim 1, wherein: The radially inner portion of the sealing 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 sealing member is configured to bend downward relative to the apex of the top surface of the embedded member when a downward force is applied to the top surface of the radially inner portion of the sealing member. The apparatus according to claim 1 , wherein the sealing member is formed of polytetrafluoroethylene. The apparatus of claim 1 , wherein the sealing member has a coefficient of friction lower than 0.

5.

6. The apparatus according to claim 1, further comprising: A retaining ring is configured to retain the sealing member on the top surface of the insert member at a position radially outward of the upward slope of the top surface of the insert member.

7. The apparatus of claim 1, further comprising: A backing member is disposed between the sealing member and the top surface of the embedding member, the backing member having an outer shape substantially the same as the outer shape of the annular disk of the sealing member.

8. An apparatus according to claim 7, wherein the backing member is configured to apply an upward resisting force through the sealing member when a downward force is applied to the top surface of the radially inner portion of the sealing member, and wherein the backing member is configured to prevent the electroplating solution from flowing on the bottom surface of the radially inner portion of the sealing member.

9. The apparatus of claim 7, wherein the backing member is formed of resilient stainless steel.

10. The apparatus of claim 7, further comprising: A retaining ring is configured to retain both the sealing member and the backing member on the top surface of the embed member at a location radially outward of the upward slope of the top surface of the embed member.

11. The apparatus of claim 1 , further comprising: A cup-shaped member having an annular shape, the cup-shaped member having a bottom surface including a radially outer portion, the radially outer portion of the cup-shaped member being configured to form a liquid seal with a top surface of the radially inner portion of the sealing member when the cup-shaped member is substantially centered over the sealing member and moves downward to contact the sealing member.

12. The apparatus of claim 11 , wherein the cup-shaped member is configured to rotate relative to the sealing member when the cup-shaped member is substantially centered above the sealing member and moves downward to contact the sealing member so that the radially outer portion of the bottom surface of the cup-shaped member is configured to slide on the top surface of the radially inner portion of the sealing member while maintaining a liquid seal with the top surface of the radially inner portion of the sealing member.

13. A sealing device for electroplating equipment used in semiconductor wafer manufacturing, comprising: An annular disk-shaped structure is configured to be mounted on the top surface of an embedded component of the electroplating equipment, the annular disk-shaped structure having flexibility so as to be physically conformal to the contour of the top surface of the embedded component when the annular disk-shaped structure is mounted on the top surface of the embedded component, so that the radial outer portion of the annular disk-shaped structure is conformal to the upward slope of the top surface of the embedded component, and the radial inner portion of the annular disk-shaped structure protrudes inward from the top surface of the embedded component, wherein the upward slope of the top surface of the embedded component is inclined upward from the peripheral area of ​​the top surface of the embedded component toward the processing area surrounded by the embedded component.

14. The sealing device of claim 13, wherein the annular disc-shaped structure has a coefficient of friction less than 0.

5.

15. The sealing device of claim 13, wherein the annular disk-shaped structure is formed of polytetrafluoroethylene.

16. The sealing device according to claim 13, further comprising: a backing member having substantially the same outer shape as the annular disk structure, the backing member being configured to be disposed between the annular disk structure and the top surface of the embedding member.

17. A sealing device according to claim 16, wherein the backing member is configured to: when a downward force is applied to the top surface of the radially inner portion of the annular disk structure, an upward resistance force is applied through the annular disk structure, and wherein the backing member is configured to prevent the electroplating solution from flowing on the bottom surface of the radially inner portion of the sealing member.

18. A method for electroplating a semiconductor wafer, comprising: An electroplating apparatus is provided, which includes an embedded member, the embedded member is 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, which is inclined upward from a peripheral area of ​​the top surface of the embedded member toward the processing area, the electroplating apparatus also includes a sealing member, which has an annular disk shape, the sealing member is positioned on the top surface of the embedded member, the sealing member is flexible so that the radially outer side of the sealing member conforms to the upward slope of the top surface of the embedded member and so that the radially inner side of the sealing member protrudes inwardly toward the processing area, the electroplating apparatus also includes a cup-shaped member with an annular shape, the cup-shaped member has a bottom surface including a radially outer side, the radially outer side is configured to: when the cup-shaped member is substantially centered above the sealing member and moves downward to contact the sealing member, form a liquid seal with the top surface of the radially inner side of the sealing member; 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; and flowing a plating solution through the processing area, a portion of the plating solution flowing over the bottom surface of the radially inner portion of the sealing member and pressing the sealing member against the cup-shaped member to assist in maintaining 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.

19. The method according to claim 18, further comprising: The cup-shaped member is rotated relative to both the embedded member and the sealing member so that the radially outer portion of the bottom surface of the cup-shaped member slides on the top surface of the radially inner portion of the sealing member while maintaining 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.

20. An embedded component of a sealing mechanism in an electroplating apparatus for semiconductor wafer manufacturing, comprising: A structural member configured to surround a processing area within the electroplating equipment, the structural member having a top surface, a portion of the top surface of the structural member having an upward slope, the upward slope being inclined upward from a peripheral area of ​​the top surface of the structural member toward the processing area, the top surface of the structural member being configured to receive and support a sealing member having an annular disk shape, wherein the radial inner portion of the sealing member protrudes inward toward the processing area, and the structural member having sufficient rigidity so that when the radial inner portion of the sealing member is pushed downward, the radial outer portion of the sealing member is conformal to the upward slope of the top surface of the embedded member.

21. An embedded component of a sealing mechanism within an electroplating device for semiconductor wafer manufacturing according to claim 20, wherein the structural component is shaped to be attached to a channel-type ion-resistive plate, and the channel-type ion-resistive plate is configured to separate the semiconductor wafer from the anode within the electroplating device.

22. An embedded component of a sealing mechanism in an electroplating device for semiconductor wafer manufacturing according to claim 20, wherein the upward slope of the top surface of the structural component is formed to force the sealing component to be arcuate upward when the sealing component is clamped downward on the top surface of the embedded component.

23. An embedded component of a sealing mechanism in an electroplating device for semiconductor wafer manufacturing according to claim 20, wherein the upward slope of the top surface of the structural component is used to preload the sealing component so that the radial inner side of the sealing component is arcuate upward to contact the cup-shaped component of the electroplating device when the cup-shaped component of the electroplating device moves to the plating position in the electroplating device.

24. A cup-shaped member of an electroplating apparatus for semiconductor wafer manufacturing, comprising: A structural member having an annular shape defined to surround a processing region, the structural member being configured to hold a semiconductor wafer in a downwardly facing orientation toward the processing region, the structural member having a bottom surface including a radially outer portion, the radially outer portion being configured to form a liquid seal with a top surface of a radially inner portion of the sealing member when the structural member is substantially centered over a sealing member and moves downwardly to contact the sealing member, wherein the structural member is configured to rotate relative to the sealing member when the structural member is substantially centered over the sealing member and moves downwardly to contact the sealing member so that the radially outer portion of the bottom surface of the structural member is configured to slide on the top surface of the radially inner portion of the sealing member while maintaining a liquid seal with the top surface of the radially inner portion of the sealing member.

25. The cup-shaped member of an electroplating apparatus for semiconductor wafer fabrication according to claim 24, wherein rotation of the structural member causes corresponding rotation of the semiconductor wafer.

26. A cup-shaped member for electroplating equipment for semiconductor wafer manufacturing according to claim 24, wherein the structural member is formed of a material having sufficient durability and low friction so that the structural member can rotate relative to the sealing member at a rotation rate of up to 200 revolutions per minute without damaging the sealing member or the structural member when the structural member contacts the sealing member.

27. The cup-shaped member of an electroplating apparatus for semiconductor wafer manufacturing according to claim 24, wherein the radially outer portion of the bottom surface of the structural member is a portion of a recessed area formed at a bottom periphery of the structural member.

28. The cup-shaped member of an electroplating apparatus for semiconductor wafer fabrication according to claim 27, wherein the recessed area is formed to provide a position where the sealing member is pressed against the structural member in a substantially uniform manner around the bottom periphery of the structural member.

29. The cup-shaped member of the electroplating equipment for semiconductor wafer manufacturing according to claim 24, wherein: The radially outer portion of the bottom surface of the structural member has a substantially horizontal positioning when the structural member is substantially centered over the sealing member and moves downward to contact the sealing member.

30. A clamping ring for an electroplating apparatus for semiconductor wafer manufacturing, comprising: A structural member configured to retain a sealing member on a top surface of an embedded member configured to surround a processing area, wherein a portion of the top surface of the embedded member has an upward slope, the upward slope inclining upward from a peripheral area of ​​the top surface of the embedded member toward the processing area, wherein the sealing member has an annular disk shape and is positioned on the top surface of the embedded member, wherein the structural member is configured to contact the top surface of the sealing member at a position radially outward of the upward slope of the top surface of the embedded member.

31. The clamping ring of an electroplating apparatus for semiconductor wafer manufacturing according to claim 30, wherein the structural member is configured to be bolted to the embedded member through the sealing member.

32. A clamping ring for an electroplating device for semiconductor wafer manufacturing according to claim 30, wherein the structural member is configured to pull the sealing member toward the top surface of the embedded member so that the sealing member is conformal with the top surface of the embedded member.

Images