Wafer chuck assembly and method of processing wafer

Abstract

A wafer chuck assembly is provided. In one embodiment, a wafer chuck assembly includes a hub, a plurality of arms mounted to the hub, and a plurality of retainers. Each arm extends outwardly from the hub and each arm has a proximal end adjacent the hub and a distal end remote from the hub. Each holder is mounted at a distal end of each respective arm, and each holder has a plurality of support pins configured to support a wafer. The embodiment of the invention also provides a method for processing the wafer.

Description

Technical Field

[0001] Embodiments of the present application relate to wafer chuck assemblies and methods of processing wafers. Background Art

[0002] Edge bevel removal, commonly referred to as EBR, is a process specifically designed to remove unwanted film from the edge of a wafer. EBR typically uses specific chemicals to remove material from the edge of the wafer. During this process, the wafer is held and rotated while the chemical is sprayed along the edge. The chemical reacts with the excess material at the edge, making it easier to remove. Subsequently, these reaction products are rinsed away. Summary of the invention

[0003] According to one aspect of an embodiment of the present application, a wafer chuck assembly is provided, comprising: a hub; a plurality of arms mounted to the hub, each arm extending outward from the hub, each arm having a proximal end adjacent to the hub and a distal end away from the hub; and a plurality of retainers, each retainer being mounted at the distal end of each corresponding arm, each retainer having a plurality of support pins configured to support a wafer.

[0004] According to another aspect of an embodiment of the present application, a wafer chuck assembly is provided, comprising: a rotatable hub; a plurality of support arms, wherein each support arm has a first end connected to the rotatable hub and a second end opposite to the first end; and a plurality of retainers configured to hold a wafer, wherein each retainer is attached to the second end of the chuck arm, wherein each retainer includes at least two support pads.

[0005] According to another aspect of an embodiment of the present application, a method for processing a wafer is provided, the method comprising: placing a wafer in a chuck assembly having a chuck arm and a plurality of wafer holders located at the end of each chuck arm, each wafer holder comprising at least two supporting pins, the wafer contacting the upper surface of the supporting pins; and rotating the chuck assembly and the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Various aspects of the present invention will be best understood from the following detailed description when read in conjunction with the accompanying drawings. It should be noted that, in accordance with standard practice in the industry, the various components are not drawn to scale. In fact, the sizes of the various components may be arbitrarily increased or reduced for clarity of discussion.

[0007] Figure 1 is a schematic diagram of a wafer chuck assembly according to some embodiments of the present disclosure.

[0008] Figure 2 is a schematic diagram of a holder of a wafer chuck assembly according to some embodiments of the present disclosure.

[0009] Figure 3is a schematic top view of a wafer chuck assembly according to some embodiments of the present disclosure.

[0010] Figure 4 is a schematic diagram of a wafer chuck assembly with a measurement system according to some embodiments of the present disclosure.

[0011] Figure 5A and Figure 5B is a schematic diagram of a monitoring system for a wafer chuck assembly according to some embodiments of the present disclosure.

[0012] Fig. 6A and Figure 6B Various embodiments of holders for wafer chuck assemblies are shown.

[0013] Figure 7 is a flow chart of an electrochemical plating process according to some embodiments of the present disclosure.

[0014] Figure 8 is a flow chart of edge bevel removal steps according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0015] The following disclosure provides many different embodiments or examples for implementing different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present invention. Of course, these are only examples and are not intended to be limiting. For example, in the following description, forming a first component above or on a second component may include an embodiment in which the first component and the second component are in direct contact, and may also include an embodiment in which an additional component is formed between the first component and the second component so that the first component and the second component are not in direct contact. Moreover, the present invention may repeat reference numbers and / or letters in various examples. This repetition is for simplicity and clarity, but does not itself specify the relationship between the various embodiments and / or configurations discussed.

[0016] It is intended to read this description of the illustrative embodiments in conjunction with the accompanying drawings, which are considered to be part of the entire written specification. In the description of the embodiments disclosed in the present invention, any reference to direction or orientation is only for the convenience of description and does not limit the scope of the present invention in any form. Terms such as "below", "above", "horizontally", "vertically", "above...", "below...", "upwardly", "downwardly", "top", "bottom" and other spatial relative positions and their derivatives (e.g., "horizontally", "downwardly", "upwardly", etc.) should be interpreted as representing the orientation described and shown at the time in the accompanying drawings discussed. These spatial relative position terms are only for the convenience of description and do not require the device to be constructed or operated in a specific orientation. Terms such as "attachment", "affiliated", "connection" and "interconnection" refer to the relationship in which a structure is fixed or attached to another structure directly or through an intermediate structure, as well as removable or rigid attachments or relationships, unless otherwise described. In addition, the features and benefits of the present disclosure are illustrated by reference to embodiments. Therefore, the present disclosure expressly should not be limited in expression to these preferred embodiments showing non-limiting combinations of components that may exist alone or other combinations of components; the scope of the present disclosure is defined by the appended claims.

[0017] The fabrication of integrated circuits typically involves depositing one or more layers of metal onto the active circuit areas of a wafer. Conductive interconnects on integrated circuits are typically in the form of trenches and vias. These trenches and vias are typically formed by a damascene or dual damascene process. Electrochemical plating (ECP) can be used to form small embedded metal features due to its bottom-up fill capability and the excellent conductive properties of the deposited film.

[0018] During the electroplating process, a metal layer can be deposited in areas outside of the active circuit area, such as the edge area of ​​the wafer. For example, before electroplating, a metal layer is often deposited as a seed layer to facilitate the subsequent electroplating operation. This can be done using methods such as physical vapor deposition (PVD) and may result in the seed layer covering the edge areas of the wafer, such as the front edge area and the sides. In a subsequent electroplating process, an additional electroplated metal layer is further formed on top of the seed layer.

[0019] Embodiments such as those discussed below provide an edge bevel removal (EBR) process on the edge region of the wafer after electroplating to remove the seed layer and the electroplated metal layer.

[0020] The EBR process can utilize a wafer chuck assembly to achieve the effect of stably holding and rotating the wafer. In addition, the parts of the wafer chuck assembly that contact and support the wafer can be wear-resistant, thereby reducing the frequency of replacement, thereby achieving an overall improvement in wafer production efficiency.

[0021] Figure 1 is a schematic side view of a wafer chuck assembly 1 according to some embodiments. Figure 1 As shown, the wafer assembly 1 may include a rotatable center hub 11, a plurality of support arms 12, a plurality of holders 13, and a nozzle 15. The support arms 12 may be mounted to the rotatable center hub 11 and extend outward from the rotatable center hub 11. That is, each support arm 12 may include a proximal end 121 adjacent to the rotatable center hub 11 and a distal end 122 away from the rotatable center hub 11, and the support arm 12 may extend outward between the proximal end 121 and the distal end 122. In some embodiments, the wafer chuck assembly 1 includes three support arms 12, and the support arms 12 may be positioned around the rotatable center hub 11 at radial intervals of 120°, 240°, and 360°. This arrangement ensures stability and balance during wafer processing.

[0022] Further, see Figure 1 , each retainer 13 can be mounted at the distal end 122 of the support arm 12. When the semiconductor wafer is provided to the wafer chuck assembly 1, the retainer 13 can be configured to engage and / or hold the semiconductor wafer. When the rotatable center hub 11 rotates, it drives the support arm 12 and the retainer 13 mounted on the support arm 12 to rotate as well, so that the semiconductor wafer engaged and / or held by the retainer 13 rotates therewith. In some embodiments, the wafer chuck assembly 1 can be designed to hold the semiconductor wafer firmly in place, and the semiconductor wafer can be rotated at various speeds ranging from about 0RPM to about 6000RPM by the rotatable center hub 11. In some embodiments of the present disclosure, the rotatable center hub 11 can provide a rotation rate ranging between about 0RPM and about 6000RPM. Generally speaking, when performing an edge bevel removal (EBR) process, the semiconductor wafer may be rotated in a range from about 0 RPM to about 2500 RPM, such as in a range from about 100 RPM to about 1500 RPM, or such as in a range from about 500 RPM to about 1300 RPM.

[0023] The nozzle 15 may have an outward-facing jet port from which the liquid etchant may be ejected onto the semiconductor wafer to remove the metal near the edge of the semiconductor wafer. For example, the liquid etchant may be applied to the edge of the semiconductor wafer in a thin stream, forming a thin viscous layer near its application point on the semiconductor wafer, thereby preventing or reducing the liquid etchant from splashing onto the inside of the semiconductor wafer and removing the metal from the active circuit area. Due to the radial velocity component of the applied liquid etchant and the centripetal acceleration effect of the rotating wafer, the thin viscous layer flows outward, flows downward over the side edge, and may also flow to the back of the semiconductor wafer, thereby achieving the purpose of removing metal from the edge of the wafer. In some embodiments, the EBR process is performed under the following conditions: for a wafer having a diameter of about 290 mm to about 310 mm, the liquid etchant is dispersed at a rate of about 0.2 ml / second to about 3 ml / second, such as about 0.3 ml / second to about 0.4 ml / second, delivering a total of about 3 ml to about 15 ml of liquid etchant. In some embodiments, the liquid etchant may be supplied by two or more operations with different flow rates. For example, in a first operation, about 1 ml to 2 ml of liquid etchant is provided at a rate of about 0.4 ml / sec to 0.5 ml / sec, followed by a second operation in which about 8 ml to 12 ml of liquid etchant is provided at a rate of about 0.2 ml / sec to 0.4 ml / sec.

[0024] The etchant may include an acid and an oxidant. Examples of acids include sulfuric acid, hydrohalic acid, chromic acid, and nitric acid. Examples of oxidants include perchloric acid, hydrofluoric acid, and sulfuric acid. In some embodiments, the etchant for copper EBR may be an aqueous solution of H2SO4 (sulfuric acid) and H2O2 (hydrogen peroxide). In some embodiments, the etchant contains about 15% to 25% by weight of H2SO4 and 20% to 35% by weight of H2O2. Nearly neutral and alkaline etchants that are easily complexed with dissolved metals may also be used, such as a combination of glycine or ethylenediamine with hydrogen peroxide at a pH of about 9. Typically, the liquid etchant may be selected based on the physical properties of the etching system, such as surface tension, contact angle, and viscosity.

[0025] After applying the desired amount of liquid etchant to the edge of the wafer, deionized water may be applied to the front side of the wafer as a post-EBR rinse through nozzle 15. Deionized water is applied to the entire wafer as a whole. This application of deionized water may continue until the subsequent operations of backside etching and backside rinsing in order to protect the wafer from any extraneous backside etchant spray and damage. When applying deionized water, the dispensing arm moves the etchant nozzle away from the wafer.

[0026] Figure 21 is a schematic diagram of a holder 13 of a wafer chuck assembly 1 according to some embodiments. As described above, the holder 13 may be located at the distal end 122 of the support arm 12. The holder 13 may include a base 131, two support pins 133-1 / 133-2 (collectively referred to as support pins 133), and an alignment member 135. Figure 2 As shown, the support pins 133 can be disposed on the base 131 of the holder 13. When the semiconductor wafer is disposed in the wafer chuck assembly 1 and is held / engaged by the holder 13, the support pins 133 can directly contact and support the bottom surface of the semiconductor wafer. The semiconductor wafer is placed on the support pins 133 (located on the support arm 12) by static friction. In some embodiments, the support pins 133 are located about 5 to 20 mm, for example, about 5 to 10 mm from the edge of the semiconductor wafer. The size / design of the support pins provides sufficient friction to prevent the wafer from flying off the chuck when slightly off-center (for example, when aligned with the specification tolerance of the edge bevel removal process), reduce or prevent sliding when accelerating the wafer from rest (for example, at a rate of 50 to 300 rpm / second (for example, 100 rpm / second)) to the EBR rotation rate, and prevent / reduce shedding or removal of particles.

[0027] In order to fix the wafer and reduce / prevent sliding, each retainer 13 can be equipped with a plurality of support pins 133 to support and contact the bottom of the semiconductor wafer. This ensures that the semiconductor wafer remains stable during the EBR rotation process. In some embodiments, the support pins 133 may include support pads 1330. When the support pins 133 support the semiconductor wafer, the support pads 1330 directly contact the bottom surface of the semiconductor wafer. In some embodiments, the support pads 1330 may be replaceable. In some embodiments, the two support pins 133 may be spaced apart by a distance D1, which may be approximately equal to or greater than the width of the support pins 133 or the diameter of the support pads 1330.

[0028] In addition, in order to prevent or reduce the shedding or removal of particles, the support pin 133 can be resistant to chemical corrosion and wear. That is, the support pad 1330 can resist chemical corrosion and wear. In some embodiments, the support pad 1330 of the support pin 133 may include a FFKM (perfluoroelastomer) elastomer. That is, the support pin 133 may include a FFKM (perfluoroelastomer) material. FFKM (perfluoroelastomer) material is a synthetic rubber having a variety of properties, such as chemical resistance (for example, FFKM has excellent chemical resistance due to its fully fluorinated molecular structure and can withstand exposure to a variety of corrosive chemicals, acids and solvents), high temperature resistance (for example, FFKM can operate effectively at temperatures up to 300°C (572°F) and maintain its mechanical properties even in extremely hot conditions), and low temperature flexibility (for example, certain grades of FFKM also maintain their elasticity at extremely low temperatures, making them suitable for a wide range of operating conditions). Exemplary FFKM elastomers include Perfluorinated elastomers, Perfluorinated elastomer, Paroflor TM Perfluorinated elastomer, Hiflor TM Perfluorinated elastomers, Perfluorinated elastomers, Perfluorinated elastomers and Perfluorinated elastomer. When the support pad 1330 is made of FFKM material, it significantly reduces pad wear and extends the frequency of pad replacement. The replacement cycle can be extended, for example, from once every two weeks to once every 12 weeks.

[0029] The alignment features 135 may be used to facilitate proper alignment of the semiconductor wafer on the wafer chuck assembly 1 when the semiconductor wafer is transferred to the wafer chuck assembly 1 .

[0030] refer to Figure 3, a top view shows a semiconductor wafer 20 provided to a wafer chuck assembly 1 and held by a holder 13 of the wafer chuck assembly 1. The wafer chuck assembly 1 may have a support arm 12 extending outwardly from a rotatable center hub 11 and positioned below the semiconductor wafer 20. The holder 13 may be mounted to a distal end 122 of the support arm 12 and may be at least partially positioned below the semiconductor wafer 20. The holder 13 may include two support pins 133-1 / 133-2. The holder 13 may be configured to hold and / or engage the semiconductor wafer 20, and the two support pins 133-1 / 133-2 of each holder 13 are configured to support and contact the bottom surface of the semiconductor wafer 20. That is, there is a two-point contact between the bottom surface of the semiconductor wafer 20 and each holder 13. Since each retainer 13 makes two-point contact with the lower surface of the semiconductor wafer 20 to support and retain the semiconductor wafer 20 , the wafer chuck assembly 1 can more effectively maintain the stability of the semiconductor wafer 20 during the implementation of the EBR process.

[0031] In some embodiments, the support pins 133-1 / 133-2 may be positioned side by side. Figure 3 , a horizontal distance D3 from the support pin 133-1 to the center of the semiconductor wafer 20 may be substantially equal to a horizontal distance D2 from the support pin 133-2 to the center of the semiconductor wafer 20. Thus, if one of the two support pins 133-1, 133-2 becomes excessively worn, the other support pin 133-1, 133-2 may continue to support and contact the bottom surface of the semiconductor wafer 20 at approximately the same level, thereby maintaining the stability of the wafer.

[0032] Figure 4 is a schematic diagram of a wafer chuck assembly 1 with a measurement system 3 according to some embodiments. Figure 4 As shown, the measurement system 3 may include an image sensor 31, a controller 33, a computer 35, and an inspection device 37. In some embodiments, the image sensor 31 may include a CMOS image sensor. The image sensor 31 may include two CCD cameras 311, 312. The two CCD cameras may each be roughly aligned with the edge area of ​​the semiconductor wafer 20. When the wafer chuck assembly 1 rotates the semiconductor wafer 20 by rotating the rotatable center hub 11 and performing an EBR (edge ​​bevel removal) process, the two CCD cameras 311 and 312 may capture image information of the edge area of ​​the semiconductor wafer 20, including the change of the wafer edge area and the wafer position during the EBR process.

[0033] The controller 33 may be electrically connected to the image sensor 31. In some embodiments, the controller 33 may include an MCU controller. The controller 33 is configured to control the CCD cameras 311 and 312 of the image sensor 31. The image sensor 31 may send image information captured by the CCD cameras 311 and 312 to the controller 33. In some embodiments, the image information captured by the CCD cameras 311 and 312 may be color image information. The controller 33 may convert the color image information into grayscale image information and send the grayscale image information to the computer 35.

[0034] After receiving the grayscale image information provided by the controller 33, the computer 35 can calculate the width data of the edge area of ​​the semiconductor wafer 20 based on the grayscale image data. In some embodiments, the computer 35 includes a monitor, which can immediately display the grayscale image information about the edge area of ​​the semiconductor wafer 20 and the relevant information about the edge area of ​​the semiconductor wafer 20. In addition, the computer 35 can send the calculated width data of the edge area of ​​the semiconductor wafer 20 to the inspection device 37, and the inspection device can determine whether the edge area of ​​the semiconductor wafer 20 meets the standard based on the width data from the computer 35. In some embodiments, the inspection device 37 can record the width data of the edge area of ​​the semiconductor wafer 20.

[0035] like Figure 5A and Figure 5B As shown, the wafer chuck assembly may include a monitoring system 5. In some embodiments, the monitoring system 5 may include a controller and two pairs of laser emitters and receivers, such as a first laser emitter 51 and a receiver 52 pair and a second laser emitter 53 and a receiver 54 pair. The two pairs of laser emitters and receivers may be electrically connected to the controller. The laser emitters 51, 53 may be positioned on opposite sides of the receivers 52, 54 relative to the holder 13. The laser emitter 51 may be substantially aligned with the receiver 52. Therefore, the laser emitter 51 is configured to emit laser light L1 toward the receiver 52, and the receiver 52 is configured to receive the laser light L1 from the laser emitter 51. In addition, the laser emitter 53 may be substantially aligned with the receiver 54. Therefore, the laser emitter 53 is configured to emit laser light L2 toward the receiver 54, and the receiver 54 is configured to receive the laser light L2 from the laser emitter 53. In addition, the laser emitter 53 may be substantially aligned with the support pad 1330 of the support pin 133 of the holder 13. Therefore, in some cases, the laser light L2 emitted by the laser emitter 53 may be blocked by the support pad 1330 of the support pin 133 , thereby causing the receiver 54 to be unable to receive the laser light L2 emitted by the laser 53 .

[0036] Figure 5AThe support pad 1330 of the support pin 133 of the retainer 13 is shown to be still in a qualified and usable state. Figure 5A As shown, the semiconductor wafer 20 may be supported by the support pins 133 of the holder 13, and the bottom surface of the semiconductor wafer 20 may be in contact with the support pads 1330 of the support pins 133. The laser emitter 51 may emit laser light L1 above the semiconductor wafer 20, and the receiver 52 may receive the laser light L1 from the laser emitter 51. In addition, the laser emitter 53 may emit laser light L2 to the receiver 54. Since the support pads 1330 of the support pins 133 of the holder 13 are still in a qualified and usable state, the support pads 1330 of the support pins 133 may lift the semiconductor wafer 20 to a certain height, and the laser light L2 may pass from under the semiconductor wafer 20. However, the laser emitter 53 may be substantially aligned with the support pads 1330 of the support pins 133, so the support pads 1330 of the support pins 133 may block the laser light L2 emitted from the laser emitter 53, and the receiver 54 may not receive the laser light L2. That is, when the receiver 52 is able to receive the laser L1 from the laser transmitter 51, but the receiver 54 is unable to receive the laser L2, it indicates that the support pad 1330 of the support pin 133 is still in a qualified and usable state.

[0037] Figure 5B It shows that the support pads 1330 of the support pins 133 of the holder 13 have been worn to the point where they need to be replaced. When the support pads 1330 of the support pins 133 are worn to the point where they can no longer be used and need to be replaced, the height of the semiconductor wafer 20 supported by them may drop to a level that allows the laser light L2 emitted by the laser emitter 53 to pass through the top of the semiconductor wafer 20 and be received by the receiver 54. That is, when the receiver 52 is able to receive the laser light L1 from the laser emitter 51 and the receiver 54 is able to receive the laser light L2, it indicates that the support pads 1330 of the support pins 133 of the holder 13 have been worn to the point where they need to be replaced.

[0038] In addition, as described above, when the semiconductor wafer 20 is supported by the support pins 133 of the holder 13, the laser light L1 emitted from the laser emitter 51 may pass through the semiconductor wafer 20. During the process of moving the wafer 20 away from the holder 13 or placing the semiconductor wafer 20 on the holder 13, the semiconductor wafer 20 may temporarily block the laser light L1 so that the user can know the movement of the semiconductor wafer 20.

[0039] When the receiver 52 receives or does not receive the laser light L1 emitted by the laser emitter 51 and / or when the receiver 54 receives or does not receive the laser light L2 emitted by the emitter 53, the controller may provide relevant information accordingly. For example, when the receiver 54 receives the laser light L2 emitted by the emitter 53, the controller may send a notification message or an alarm to inform the user that the support pad 1330 of the support pin 133 of the holder 13 has been worn to the extent that it needs to be replaced.

[0040] In some embodiments, the measurement system 3 and the monitoring system may be independent of each other.

[0041] Fig. 6A An embodiment of a holder 17 that can be mounted to the distal end 122 of the support arm 12 of the wafer chuck assembly 1 is shown. The holder 17 may include a base 171, three support pins 173, and an alignment member 175. The pins 173 may be disposed on the base 171 of the holder 17. In some embodiments, the three support pins 173 may be arranged substantially in a row along the width of the base 171. When the semiconductor wafer is disposed in the wafer chuck assembly 1 and is held / engaged by the holder 17, the support pins 173 may contact and support the bottom surface of the semiconductor wafer. The semiconductor wafer may be placed on the support pins 173 (located on the support arm 12) by static friction. The support pins 173 may be located about 5 to 20 mm, for example, about 5 to 10 mm from the edge of the semiconductor wafer. In some embodiments, the support pins 173 may include support pads 1730 located on top thereof. That is, when the wafer is supported by the support pins 173 of the holder 17, the support pads 1730 may directly contact the bottom surface of the wafer.

[0042] Since the holder 17 may include three supporting pins, when the semiconductor wafer is supported and / or held by the holder, there is a three-point contact between the bottom surface of the semiconductor wafer and each holder 17. Since each holder 17 makes three-point contact with the lower surface of the semiconductor wafer 20 to support and hold the semiconductor wafer, the wafer chuck assembly 1 can more effectively maintain the stability of the semiconductor wafer during the implementation of the EBR (edge ​​bevel removal) process.

[0043] In addition, the support pad 1730 can resist chemical corrosion and wear. In some embodiments, the support pad 1730 of the support pin 173 may include FFKM (perfluoroelastomer) elastomer. That is, the support pin 173 may include FFKM (perfluoroelastomer) material.

[0044] Figure 6BAnother embodiment of a holder 18 that can be mounted to the distal end 122 of the support arm 12 of the wafer chuck assembly 1 is shown. The holder 18 may include a base 181, five support pins 183, and an alignment member 185. The pins 183 may be disposed on the base 181 of the holder 18. In some embodiments, the support pins 183 may be arranged substantially in a row along the width of the base 181. When the semiconductor wafer is disposed in the wafer chuck assembly 1 and is held / engaged by the holder 18, the support pins 183 may contact and support the bottom surface of the semiconductor wafer. The semiconductor wafer may be placed on the support pins 183 (located on the support arm 12) by static friction. The support pins 183 may be located about 5 to about 20 mm, for example, about 5 to about 10 mm, from the edge of the semiconductor wafer. In some embodiments, the support pins 183 may include support pads 1830 located on top thereof. That is, when the wafer is supported by the support pins 183 of the holder 18, the support pads 1830 may directly contact the bottom surface of the wafer.

[0045] Since the holder 18 may include five supporting pins, when the semiconductor wafer is supported and / or held by the holder 18, there is a five-point contact between the bottom surface of the semiconductor wafer and each holder 18. Since each holder 18 makes five-point contact with the lower surface of the semiconductor wafer 20 to support and hold the semiconductor wafer, the wafer chuck assembly 1 can more effectively maintain the stability of the semiconductor wafer during the implementation of the EBR (edge ​​bevel removal) process.

[0046] In addition, the support pad 1830 can resist chemical corrosion and wear. In some embodiments, the support pad 1830 of the support pin 183 can include FFKM (perfluoroelastomer) elastomer. That is, the support pin 183 can include FFKM (perfluoroelastomer) material.

[0047] Figure 7 is a flow chart of an electrochemical plating process 7 according to some embodiments. Electrochemical plating (ECP) 7 is a process of electroplating on a material surface using an electrochemical reaction. The process of ECP 7 may include a copper electroplating step 71, an edge bevel removal step 73, and an annealing step 75.

[0048] The copper plating step 71 may involve electrochemically depositing a copper layer on a substrate (semiconductor wafer). The copper plating step 71 may be an initial step in the ECP process 7. It may involve immersing the substrate in an electrolyte solution containing copper ions. By applying a specific voltage to the substrate surface, the copper ions are reduced and deposited as a copper metal layer. This electrochemical reaction may form a uniform and adherent copper coating on the substrate. The copper plating step 71 provides conductivity and acts as a seed layer for subsequent electroplating processes.

[0049] The edge bevel removal step 73 eliminates / reduces the beveled edges that may be formed during the electroplating process. The beveled edges may cause difficulties for subsequent processes. In some embodiments, the edge bevel removal step 73 may include a chemical etching method. The chemical etching method may utilize a chemical solution to selectively remove the beveled portion of the substrate to provide a flatter and more uniform surface for further processing.

[0050] The annealing step 75 involves a heat treatment process that eliminates stress and improves the crystal structure of the copper layer to provide better conductivity and mechanical properties. Annealing is the heating of the copper metal to a specific temperature and then slowly cooling it. This controlled heating and cooling process allows for atomic redistribution and eliminates internal stresses, resulting in a more stable and structurally sound copper layer. Annealing also enhances the electrical and mechanical properties of the copper, making it more suitable for subsequent processing steps.

[0051] Figure 8 According to some embodiments Figure 7 Flow chart of the edge bevel removal step 73.

[0052] In operation 731, the semiconductor wafer 20 may be placed onto the wafer chuck assembly 1. The holder 13 of the wafer chuck assembly 1 is responsible for holding the semiconductor wafer 20 securely in place. The support pins 133 of each holder may provide support to the bottom surface of the semiconductor wafer 20. In addition, an alignment member 135 may be included in each holder 13 to engage the edge of the semiconductor wafer 20, ensuring secure holding. To ensure proper support, each holder 13 includes a plurality of support pins 133 configured to support the bottom surface of the semiconductor wafer 20. These support pins 133 may be equipped with support pads 1330, which may be in direct contact with the bottom surface of the semiconductor wafer 20. This design allows for multiple contact points between the semiconductor wafer 20 and each holder 13 when the semiconductor wafer 20 is placed and supported by the wafer chuck assembly 1.

[0053] In some embodiments, the support pad 1330 of the support pin 133 may include FFKM (perfluoroelastomer) material. The FFKM support pad 1330 can ensure reliable and durable contact between the support pin 133 and the semiconductor wafer 20, further enhancing the stability and accuracy of the wafer chuck assembly 1.

[0054] In operation 733, the semiconductor wafer 20 can be positioned on the holder 13, which is connected to the rotatable center hub 11 through the support arm 12. Once the semiconductor wafer 20 is in place, the rotatable center hub 11 can be started and started to rotate. As a result, the holder 13 and the semiconductor wafer 20 also start to rotate around the rotatable center hub 11.

[0055] In order to ensure the stability of the semiconductor wafer 20 during rotation, each holder 13 can be equipped with a plurality of support pins 133. These support pins 133 are positioned to provide multi-point contact between the bottom surface of the semiconductor wafer 20 and the holder 13. This design feature ensures that the semiconductor wafer remains firmly in place and does not shake or shift during rotation. Any instability or movement of the wafer during this process may result in uneven material removal or wafer damage. By utilizing the plurality of support pins 133 on each holder 13, the semiconductor wafer 20 can be stably held in place, thereby allowing accurate and controlled rotation during the EBR process.

[0056] In operation 735, a liquid etchant may be applied to the edge region of the rotating semiconductor wafer 20 through the nozzle 15, thereby removing the metal located in the edge region of the semiconductor wafer 20. The liquid etchant is evenly distributed in the edge region of the semiconductor wafer 20, avoiding / reducing excessive or insufficient metal removal, and preventing / reducing metal splashing onto the active region of the semiconductor wafer 20.

[0057] The etchant may include an acid and an oxidant. Examples of useful acids include sulfuric acid, hydrohalic acid, chromic acid, and nitric acid. Examples of oxidants include perchloric acid, hydrofluoric acid, and sulfuric acid. In some embodiments, the etchant for copper EBR may be an aqueous solution of H2SO4 (sulfuric acid) and H2O2 (hydrogen peroxide). In some embodiments, the etchant contains about 15% to 25% by weight of H2SO4 and 20% to 35% by weight of H2O2.

[0058] In operation 737 , when the holder 13 of the wafer chuck assembly 1 rotates the semiconductor wafer 20 and / or applies liquid etchant to an edge region of the semiconductor wafer 20 , the measurement system 3 may detect the semiconductor wafer 20 and the monitoring system 5 may monitor the holder 13 of the wafer chuck assembly.

[0059] The measurement system 3 may be equipped with an image sensor 31 configured to capture detailed image information of the edge region of the semiconductor wafer 20. In addition, the measurement system 3 may further include a controller 33, a computer 35, and an inspection device 37. The controller 33 may convert the image information captured by the image sensor 31 into information that can be calculated by the computer 35. The computer may calculate the width data of the edge region of the wafer based on the information from the controller. The inspection device 37 may determine whether the edge region of the wafer meets the standard based on the width data from the computer 35. That is, the measurement system 3 is capable of efficiently and accurately analyzing the edge region of the wafer and its position during the EBR process.

[0060] The measuring system 3 may include a monitoring system 5, which may include two pairs of laser emitters and receivers. These components may be positioned on opposite sides of the holder 13. The first pair includes a laser emitter 51 and a receiver 52, while the second pair includes a laser emitter 53 and a receiver 54. The laser emitter 51 may emit laser light L1 to the receiver 52, and the receiver 52 may receive the light. Similarly, the laser emitter 53 may emit laser light L2 to the receiver 54, and the receiver 54 may receive the light.

[0061] In some embodiments, the laser emitter 51 and the receiver 52 may be located higher than the laser emitter 53 and the receiver 54. Such positioning allows for effective detection and monitoring of the support pads 1330 of the support pins 133.

[0062] When the support pad 1330 of the support pin 133 is in good condition, the laser light L1 from the laser emitter 51 can pass through above the semiconductor wafer 20 and be received by the receiver 52. However, the laser light L2 from the laser emitter 53 can pass through below the semiconductor wafer 20 and be blocked by the support pad 1330. As a result, the receiver 52 cannot receive the laser light L2.

[0063] On the other hand, when the support pad 1330 is worn and needs to be replaced, the laser light L1 from the laser emitter 51 can still pass through the top of the semiconductor wafer 20 and be received by the receiver 52. In addition, the laser light L2 emitted by the laser emitter 53 can also pass through the top of the semiconductor wafer 20 and be detected by the receiver 54. This change in the detection pattern indicates that the support pad 1330 of the support pin 133 needs to be replaced.

[0064] By utilizing the monitoring system 5, the user can determine the condition of the support pads 1330 and take appropriate action. The system provides a reliable and effective method to monitor the wear of the support pads 1330, ensuring smooth operation of the holder 13 and semiconductor wafer 20.

[0065] The above process is for illustrative purposes. Figure 2 The above process can be used to describe the structure shown in Fig. 6A and Figure 6B The structure shown.

[0066] It should also be understood that the aforementioned devices and systems can be used in the EBR process. The wafer chuck assembly of the present disclosure can provide multi-point contact between the bottom surface of the wafer and each retainer, thereby allowing the wafer to rotate stably during the EBR process in the wafer chuck assembly. This configuration significantly reduces the probability of EBR alarms, by about 80%. In addition, the support pins of the retainer can include FFKM (perfluoroelastomer) material with wear resistance and chemical corrosion resistance. When the support pad 1330 is made of FFKM material, it significantly reduces pad wear and extends the frequency of pad replacement. In addition, the wafer chuck assembly of the present disclosure can include a monitoring system. The monitoring system can automatically monitor the use status of the support pad of the support pin in real time. The user can use the monitoring system to determine whether the support pad needs to be replaced.

[0067] According to one embodiment, a wafer chuck assembly includes a hub, a plurality of arms mounted to the hub, and a plurality of holders. Each arm extends outward from the hub, and each arm has a proximal end adjacent to the hub and a distal end away from the hub. Each holder is mounted at the distal end of each corresponding arm, and each holder has a plurality of support pins configured to support a wafer. According to one embodiment of the present disclosure, the horizontal distances from each support pin to the center of the hub are substantially equal to each other. According to one embodiment of the present disclosure, the support pins include FFKM (perfluoroelastomer) material. According to one embodiment of the present disclosure, the wafer chuck assembly also includes a monitoring system configured to monitor the support pins. According to one embodiment of the present disclosure, the monitoring system includes: a first laser transmitter configured to emit a first laser to the support pin; a first laser receiver configured to receive the first laser emitted from the laser transmitter; a second laser transmitter configured to emit a second laser above the wafer supported by the support pin; and a second laser receiver configured to receive the second laser emitted from the second laser transmitter. The first laser path between the first laser transmitter and the first laser receiver is lower than the second laser path between the second laser transmitter and the second laser receiver relative to the upper surface of the plurality of holders. According to one embodiment of the present disclosure, when the first laser emitted by the first laser emitter reaches the first receiver and the second laser emitted by the second laser emitter reaches the second receiver, the monitoring system is configured to issue an alarm, indicating that the support pin is worn and needs to be replaced. According to one embodiment of the present disclosure, the number of support pins provided by each retainer is two, three or five.

[0068] According to another embodiment of the present disclosure, a wafer chuck assembly includes a rotatable hub, a plurality of support arms, and a plurality of retainers. Each support arm has a first end connected to the rotatable hub and a second end opposite to the first end. Each retainer is attached to the second end of the chuck arm. The retainer is configured to hold a wafer. Each retainer includes at least two support pads, which are configured to provide multi-point contact between the bottom surface of the wafer and the retainer when the wafer is held by the retainer. According to another embodiment of the present disclosure, when the wafer is held by the retainer, at least two support pads directly contact the bottom of the wafer. According to another embodiment of the present disclosure, the number of support pads provided by each retainer is two, three or five. According to another embodiment of the present disclosure, the support pads are spaced a certain distance from each other. According to another embodiment of the present disclosure, the distance is equal to or greater than the diameter of the support pad. According to another embodiment of the present disclosure, the support pad includes FFKM (perfluoroelastomer) material. According to another embodiment of the present disclosure, the wafer chuck assembly includes a monitoring system configured to monitor the wear condition of the support pad. According to another embodiment of the present disclosure, a monitoring system is configured to emit laser light to sense a support pad and determine a wear condition of the support pad.

[0069] According to one embodiment of the present disclosure, a method for processing a wafer includes: placing a wafer in a wafer chuck assembly, the wafer chuck assembly having a chuck arm and a plurality of wafer holders at the end of the chuck arm, each wafer holder including at least two support pins, the wafer contacting the upper surface of the support pins; and rotating the chuck assembly and the wafer. According to one embodiment of the present disclosure, the method includes: providing an etchant to an edge bevel area of ​​the wafer while rotating the wafer. According to one embodiment of the present disclosure, the support pins include FFKM material. According to one embodiment of the present disclosure, the method includes: monitoring the wear condition of the support pins by a laser transmitter and a laser receiver. According to one embodiment of the present disclosure, the method includes providing an alarm when the laser receiver receives a laser emitted from the laser transmitter.

[0070] The components of several embodiments are discussed above so that those skilled in the art can better understand the various embodiments of the present invention. It should be understood by those skilled in the art that the present invention can be easily used as a basis to design or change other processing and structures to achieve the same purpose and / or achieve the same advantages as the embodiments introduced in the present invention. It should also be appreciated by those skilled in the art that these equivalent structures do not deviate from the spirit and scope of the present invention, and that various changes, substitutions and modifications may be made without departing from the spirit and scope of the present invention.

Claims

1. A wafer chuck assembly, comprising: hub; a plurality of arms mounted to the hub, each arm extending outwardly from the hub, each arm having a proximal end adjacent the hub and a distal end distal from the hub; as well as A plurality of holders are each mounted at a distal end of each respective arm, each holder having a plurality of support pins configured to support a wafer.

2. The wafer chuck assembly according to claim 1, wherein: Horizontal distances from each of the support pins to the center of the hub are substantially equal to each other.

3. The wafer chuck assembly according to claim 1, wherein: The support pin includes a perfluoroelastomer material. 4 . The wafer chuck assembly of claim 1 , further comprising a monitoring system configured to monitor the support pins.

5. The wafer chuck assembly according to claim 4, wherein: The monitoring system comprises: a first laser emitter, configured to emit a first laser toward the support pin; a first laser receiver configured to receive a first laser emitted from the laser transmitter; a second laser emitter configured to emit a second laser above the wafer supported by the support pins; and a second laser receiver configured to receive a second laser emitted from the second laser transmitter, wherein a first laser path between the first laser transmitter and the first laser receiver is lower than a second laser path between the second laser transmitter and the second laser receiver relative to an upper surface of the plurality of holders.

6. The wafer chuck assembly according to claim 5, wherein: The monitoring system is configured to send an alarm when a first laser emitted from the first laser emitter reaches the first receiver and a second laser emitted from the second laser emitter reaches the second receiver.

7. A wafer chuck assembly, comprising: a rotatable hub; a plurality of support arms, wherein each support arm has a first end connected to the rotatable hub and a second end opposite the first end; and A plurality of holders are configured to hold a wafer, wherein each of the holders is attached to the second end of the chuck arm, wherein each of the holders includes at least two support pads.

8. The wafer chuck assembly according to claim 7, wherein: When the wafer is held by the holder, the at least two support pads directly contact a bottom of the wafer.

9. The wafer chuck assembly according to claim 7, wherein: The support pads are spaced a distance apart from each other.

10. A method for processing a wafer, the method comprising: placing the wafer in a chuck assembly having a chuck arm and a plurality of wafer holders at an end of each of the chuck arms, each of the wafer holders including at least two support pins, the wafer contacting upper surfaces of the support pins; and The chuck assembly and the wafer are rotated.

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