Wafer cleaning device

Abstract

The application discloses a wafer cleaning device, which comprises a clamping assembly for horizontally clamping and driving wafer rotation, and a brush cleaning assembly arranged on the side of the clamping assembly. The brush cleaning assembly comprises a swing arm which can swing to the upper side of the clamping assembly, and a cleaning brush arranged on the swing arm and swinging along the radius direction of the wafer to clean the wafer. The cleaning brush moves along the vertical direction with the swing arm and presses against the wafer surface, and the cleaning brush can rotate around the vertical axis to clean the wafer.

Description

Technical Field

[0001] This invention belongs to the field of wafer post-processing technology, and more specifically, relates to a wafer cleaning device. Background Technology

[0002] The integrated circuit industry is the core of the information technology industry, playing a crucial role in promoting the digital and intelligent transformation and upgrading of the manufacturing industry. Chips are the carriers of integrated circuits, and chip manufacturing involves processes such as integrated circuit design, wafer manufacturing, wafer processing, electrical measurement, dicing, packaging, and testing.

[0003] With the continuous development of integrated circuit technology, the wafer cleaning process is becoming increasingly important for improving the yield of wafer manufacturing. At the same time, the requirements for cleaning effect are becoming more and more stringent. Brushing, as an efficient technology for removing contaminants, is widely used in wafer manufacturing, especially in the post-processing of wafers after chemical mechanical polishing.

[0004] Existing washing devices include a horizontal translation platform / vertical lifting device to drive the washing arms in horizontal reciprocating motion and vertical up-and-down motion. In this technical solution, the movement of the device mechanism and cable carriers can introduce dust generation issues, posing a risk to the cleanliness of the wafers.

[0005] Meanwhile, in the cleaning arm, the cleaning shaft needs to drive the brush to rotate and press down, requiring a sealing structure design for the rotating components. In existing technologies, the sealing structure uses methods such as magnetohydrodynamic (MHD) seals or rotating sealing rings. However, MHD-based carrier fluids can introduce new contamination problems, and the friction introduced by rotating sealing rings can affect the brush's cleaning stability. Furthermore, rotating sealing rings are prone to wear, which is detrimental to improving the wafer cleaning effect. Summary of the Invention

[0006] This invention provides a wafer cleaning apparatus, which aims to at least solve one of the technical problems existing in the prior art.

[0007] An embodiment of the present invention provides a wafer cleaning apparatus, comprising:

[0008] Clamping assembly that horizontally clamps and drives the wafer to rotate;

[0009] A brushing component is disposed on the side of the clamping component;

[0010] The scrubbing assembly includes a swing arm that can swing above the clamping assembly, and the cleaning brush on the swing arm swings along the radial direction of the wafer to scrub the wafer.

[0011] The cleaning brush moves vertically along the swing arm and presses against the wafer surface, and the cleaning brush can rotate about the vertical axis to clean the wafer.

[0012] In some embodiments, the swing arm includes a fixed plate, the fixed plate is provided with a drive motor, the drive motor transmits power to the rotating shaft, and the cleaning brush is detachably connected to the lower end of the rotating shaft.

[0013] In some embodiments, the end of the fixed plate is provided with a mounting base, and the rotating shaft is disposed on the mounting base via an adapter; a ball bearing is disposed on the outer side of the adapter, and a linear bearing is disposed on its inner side, the linear bearing being sleeved on the outer periphery of the rotating shaft.

[0014] In some embodiments, the mounting base is further provided with a sealing ring, which covers the outer periphery of the rotating shaft and is located at the bottom of the adapter; the sealing ring is provided with a groove, which communicates with the ball bearing and the linear bearing.

[0015] In some embodiments, the mounting base is provided with a vent hole that communicates with a groove in the sealing ring and is connected to a vacuum source to draw in particulate matter that enters the groove.

[0016] In some embodiments, a gap is provided between the outer edge of the sealing ring and the inner sidewall of the mounting base, and a gap is provided between the inner edge of the sealing ring and the outer sidewall of the rotating shaft.

[0017] In some embodiments, a mounting bracket is disposed above the fixing plate, and a cylinder is disposed on the mounting bracket; the output end of the cylinder is connected to the rotating shaft through a lifting assembly to drive the rotating shaft to move in the vertical direction.

[0018] In some embodiments, the lifting assembly includes a vertical member and a horizontal member, the vertical member being slidably connected to the mounting base, and the horizontal member being connected to the top of the vertical member and fixed to the top of the rotating shaft.

[0019] In some embodiments, a self-aligning bearing and a spring are provided below the transverse member, the self-aligning bearing and the spring being sleeved on the outside of the rotating shaft; and the self-aligning bearing is provided on the upper limit plate, one end of the spring abuts against the lower part of the self-aligning bearing, and the other end abuts against the lower limit plate, the lower limit plate being provided on the rotating shaft.

[0020] In some embodiments, a pressing member is disposed on the side of the vertical member, the pressing member extending outward from the side of the vertical member; a pressure sensor is disposed below the pressing member to monitor the load applied by the cylinder to the cleaning brush.

[0021] The beneficial effects of this invention include:

[0022] a. The mounting base of the swing arm is equipped with a sealing ring. The groove on the sealing ring is connected to the ball bearing and the linear bearing. The groove is connected to an external vacuum source to adsorb particles generated during the cleaning process and ensure the cleaning effect of the wafer.

[0023] b. The rotary lifting assembly is equipped with a clean electric cylinder module to reduce the risk of particles generated by the relative movement of parts during the lifting process; the electric cylinder module is equipped with a vacuum adsorption port to adsorb external particles through vacuum, thus solving the dust generation problem during the wafer cleaning process. Attached Figure Description

[0024] The advantages of the present invention will become clearer and easier to understand through the following detailed description in conjunction with the accompanying drawings, which are merely illustrative and do not limit the scope of protection of the present invention, wherein:

[0025] Figure 1 This is a schematic diagram of a wafer cleaning apparatus provided in an embodiment of the present invention;

[0026] Figure 2 yes Figure 1 A schematic diagram of the rotating lifting assembly;

[0027] Figure 3 This is a top view of a swing arm provided in an embodiment of the present invention;

[0028] Figure 4 yes Figure 3 Sectional view of AA;

[0029] Figure 5 yes Figure 4 A magnified view of a section at point B in the middle;

[0030] Figure 6 This is a schematic diagram of a sealing ring provided in an embodiment of the present invention;

[0031] Figure 7 This is a schematic diagram of a limiting member provided in an embodiment of the present invention;

[0032] Figure 8 This is a schematic diagram of a swing arm without a protective cover according to an embodiment of the present invention. Detailed Implementation

[0033] The technical solutions of the present invention will be described in detail below with reference to specific embodiments and accompanying drawings. The embodiments described herein are specific implementations of the present invention, used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary, and should not be construed as limiting the implementation methods or the scope of protection of the present invention. In addition to the embodiments described herein, those skilled in the art can employ other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein.

[0034] The accompanying drawings in this specification are schematic diagrams used to illustrate the concept of the invention and to schematically show the shapes of the various parts and their interrelationships. It should be understood that, in order to clearly show the structure of the various components of the embodiments of the invention, the drawings are not drawn to the same scale, and the same reference numerals are used to indicate the same parts in the drawings.

[0035] In this invention, a wafer (W) is also called a substrate, which has the same meaning and practical function.

[0036] Figure 1 This is a schematic diagram of a wafer cleaning apparatus according to an embodiment of the present invention. The wafer cleaning apparatus includes:

[0037] Clamping assembly 10, which horizontally clamps and drives the wafer to rotate; Figure 1 The corresponding drive mechanism is not shown in the diagram;

[0038] A brushing assembly 20 is disposed on the side of the clamping assembly 10 to brush the horizontally clamped wafer.

[0039] Furthermore, the scrubbing assembly 20 includes a swing arm 21, which can swing above the clamping assembly 10. The cleaning brush 22 on the swing arm 21 swings along the radial direction of the wafer to scrub various areas of the wafer and remove residual particles on the wafer surface.

[0040] Furthermore, the cleaning brush 22 can move vertically with the swing arm 21 and press against the wafer surface, and the cleaning brush 22 can rotate around the vertical axis to clean the wafer. That is, the cleaning brush 22 can rotate around the central axis to enhance the cleaning effect of the wafer.

[0041] As an embodiment of the present invention, the scrubbing assembly 20 further includes a rotating lifting assembly 23, such as... Figure 1 As shown, the swing arm 21 is connected to the rotary lifting assembly 23 to realize the rotation and lifting actions of the swing arm 21, which meets the process requirements of wafer cleaning.

[0042] Figure 2This is a schematic diagram of the rotary lifting assembly 23, which includes a rotating part 23a and a lifting part 23b. The rotating part 23a is equipped with a rotary motor, the output end of which is connected to a rotating base 23c via a belt drive. The lifting part 23b is positioned above the rotating base 23c. Rotation of the rotary motor's output end causes the lifting part 23b to rotate as a whole.

[0043] Furthermore, the rotary motor configured in the rotating part 23a is a servo motor, and its output speed is reduced by a harmonic reducer. The reduction ratio of the harmonic reducer is above 1:100. Through the control of the servo motor, the rotation of the swing arm 21 is made smooth, ensuring precise control of the rotation position of the swing arm 21. This is beneficial for accurately controlling the wafer cleaning parameters and improving the wafer cleaning effect.

[0044] Furthermore, the lifting part 23b is equipped with a sliding plate 23d, which can slide in the vertical direction. The swing arm 21 is detachably connected to the sliding plate 23d to drive the swing arm 21 to slide in the vertical direction.

[0045] To reduce the risk of particles being generated by the relative movement of components during the lifting process, Figure 2 In the illustrated embodiment, the lifting unit 23b is a clean electric cylinder module. Simultaneously, the electric cylinder module is equipped with a vacuum suction port to remove external particulate matter through vacuum suction, thus solving the dust generation problem during the wafer cleaning process.

[0046] Understandably, after a wafer has been cleaned and the swing arm 21 returns to the waiting position, clean nitrogen under positive pressure can be introduced through the vacuum adsorption port to achieve an airtight seal, so as to ensure that the rinsing liquid does not enter the rotating shaft system inside the swing arm 21 and improve the stability of the operation of the cleaning assembly 20.

[0047] Figure 3 This is a top view of the swing arm 21. Figure 4 yes Figure 3 Sectional view of AA, Figure 5 yes Figure 4 A partial enlarged view at point B. The swing arm 21 includes a fixed plate 21a, and a drive motor 21b is disposed above the fixed plate 21a. The drive motor 21b can transmit power to the rotating shaft 21c, and the cleaning brush 22 is detachably connected to the lower end of the rotating shaft 21c.

[0048] Figure 4In the illustrated embodiment, a first pulley is mounted on the output shaft of the drive motor 21b, and a second pulley is mounted on the rotating shaft 21c. A belt is connected between the first and second pulleys to transmit the power output from the drive motor 21b to the rotating shaft 21c, thereby driving the rotating shaft 21c and its cleaning brush 22 to rotate around the central axis, achieving cleaning of the wafer surface. It is understood that the cleaning brush 22 in the swing arm 21 can also employ other transmission methods, such as chain drive, to drive the rotating shaft 21c to rotate.

[0049] In some embodiments, the rotating shaft 21c can also be configured with a direct drive motor to directly drive the rotating shaft 21c and the cleaning brush 22 on it to rotate, effectively simplifying the structure and improving the stability of the rotational movement of the cleaning brush 22. It should be noted that if a direct drive method is used to drive the cleaning brush 22 to rotate, sufficient working space needs to be reserved above the swing arm 21.

[0050] Furthermore, a mounting base 21d is provided at the end of the fixed plate 21a, and the rotating shaft 21c is mounted on the mounting base 21d via an adapter 21e, such as... Figure 4 As shown. Specifically, the adapter 21e is an annular component, with a ball bearing 21f disposed on the outer side of the adapter 21e and a linear bearing 21g disposed on the inner side of the adapter 21e, as... Figure 5 As shown. A linear bearing 21g is sleeved on the outer periphery of the rotating shaft 21c. The linear bearing 21g helps to ensure the straightness of the rotating shaft 21c in vertical movement and prevents the cleaning brush 22 at the end of the rotating shaft 21c from wobbling during movement, thus ensuring the cleaning effect of the wafer.

[0051] Figure 5 In the middle, the mounting base 21d is also provided with a sealing ring 21h, which covers the outer periphery of the rotating shaft 21c and is located at the bottom of the adapter 21e.

[0052] Furthermore, the sealing ring 21h is equipped with Figure 6 The groove 21h-1 shown is connected to the ball bearing 21f and the linear bearing 21g.

[0053] Figure 5 In the middle, the mounting base 21d is equipped with a vent 21j, which is connected to the groove 21h-1 of the sealing ring 21h. Furthermore, the vent 21j is connected to an external vacuum source through a pipeline to draw in particulate matter entering the groove 21h-1.

[0054] Furthermore, a gap is provided between the outer edge of the sealing ring 21h and the inner wall of the mounting base 21d, and a gap is provided between the inner edge of the sealing ring 21h and the outer wall of the rotating shaft 21c. Particles generated by the ball bearing 21f and the linear bearing 21g can enter the vent hole 21j through these gaps. In some embodiments, the horizontal width of the gap is 0.1-0.5 mm to ensure the movement accuracy of the rotating shaft 21c.

[0055] Figure 5 In the illustrated embodiment, a follower bearing 21u is also disposed on the outer periphery of the rotating shaft 21c. The outer ring of the follower bearing 21u abuts against the outer peripheral wall of the rotating shaft 21c to ensure the accuracy of the vertical movement of the rotating shaft 21c. Furthermore, there are multiple follower bearings 21u, which are evenly distributed along the central axis of the rotating shaft 21c to ensure the uniformity of the force on the rotating shaft 21c. As one aspect of this embodiment, the outer peripheral wall of the rotating shaft 21c is machined with a flat portion, and the outer ring of the follower bearing 21u abuts against the flat portion to further ensure the smoothness of the movement of the rotating shaft 21c.

[0056] Figure 5 In the adapter 21e, vertical channels 21e-1 are arranged in the thickness direction. There are multiple vertical channels 21e-1, which are evenly distributed in the adapter 21e. If the follower bearing 21u generates flammable particles during operation, they can enter the gap between the inner edge of the sealing ring 21h and the outer wall of the rotating shaft 21c through the vertical channels 21e-1, and then enter the vent hole 21j and be drawn in by the vacuum source. Figure 5 In the diagram, the path of the particulate discharge mounting base 21d is roughly drawn using dashed lines to better understand the technical solution provided by this invention.

[0057] Furthermore, the mounting base 21d is also equipped with a limiting member 21v inside. The limiting member 21v is located at the bottom of the mounting base 21d and is sleeved on the outer periphery of the rotating shaft 21c. Figure 7 This is a schematic diagram of the limiting member 21v. The limiting member 21v is a ring-shaped structure with a limiting groove 21v-1. The rotating shaft 21c is coaxially arranged with the limiting member 21v. A plug-in ring 21c-1 is arranged on the outer periphery of the rotating shaft 21c, and the plug-in ring 21c-1 of the rotating shaft 21c is disposed in the limiting groove 21v-1.

[0058] Furthermore, the limiting member 21v is equipped with a discharge hole 21v-2, which communicates with the limiting groove 21v-1. It should be noted that the gap between the inner edge of the sealing ring 21h and the outer wall of the rotating shaft 21c refers to the gap between the sealing ring 21h and the insertion ring 21c-1. If particulate matter is generated in the bearing or components inside the mounting base 21d, the particulate matter will enter the limiting groove 21v-1 and then be transported outward through the discharge hole 21v-2. Figure 7 In the embodiment shown, there are multiple discharge holes 21v-2, which are arranged circumferentially along the limiting member 21v to ensure timely discharge of particulate matter.

[0059] Furthermore, a mounting bracket 21k is disposed above the fixed plate 21a, and a cylinder is disposed on the mounting bracket 21k; the output end of the cylinder is connected to the rotating shaft 21c through the lifting assembly 21m, so as to drive the rotating shaft 21c to move in the vertical direction.

[0060] Specifically, the lifting assembly 21m includes a vertical member 21m-1 and a horizontal member 21m-2. The vertical member 21m-1 is slidably connected to the mounting base 21d, the horizontal member 21m-2 is connected to the top of the vertical member 21m-1, and the horizontal member 21m-2 is fixed to the top of the rotating shaft 21c.

[0061] Furthermore, the vertical component 21m-1 is connected to the side of the mounting base 21d via a sliding module. Specifically, the sliding module can be a precision sliding module to reduce friction between components and ensure the smooth vertical movement of the rotating shaft 21c.

[0062] Furthermore, a self-aligning bearing 21n and a spring 21p are provided below the transverse component 21m-2, and the self-aligning bearing 21n and the spring 21p are sleeved on the outside of the rotating shaft 21c; and the self-aligning bearing 21n is provided on the upper limit plate 21r, one end of the spring 21p abuts against the lower part of the self-aligning bearing 21n, and the other end of the spring 21p abuts against the lower limit plate 21s, which is provided on the rotating shaft 21c.

[0063] Figure 5 In the embodiment shown, the assembly formed by the upper limit plate 21r, the spring 21p, and the lower limit plate 21s is disposed on the upper part of the rotating shaft 21c to counteract the weight of the lifting assembly 21m and the friction between the components, thereby ensuring the accuracy of the load applied by the cleaning brush 22. Specifically, the load of the cleaning brush 22 can be applied from zero point to fully cover the range of load application and meet the process requirements of various wafer cleaning processes.

[0064] Furthermore, the side of the vertical member 21m-1 is provided with a pressing member 21m-3, such as... Figure 5 As shown, the pressing member 21m-3 extends outward from the side of the vertical member 21m-1; wherein, a pressure sensor 21t is disposed below the pressing member 21m-3 to monitor the load applied by the cylinder to the cleaning brush 22.

[0065] To enhance the protection of moving parts and prevent particles from entering the interior of the swing arm 21 during the cleaning process, the swing arm 21 is also equipped with a protective cover 21w, such as... Figure 4As shown. The protective cover 21w is made of corrosion-resistant non-metallic material to extend the service life of the swing arm 21, while also reducing the weight of the swing arm 21 and ensuring the smoothness of its movement. In addition, the protective cover 21w can also prevent particles generated inside the swing arm 21 from diffusing onto the wafer, thus ensuring the effectiveness of wafer cleaning.

[0066] Figure 8 This is a schematic diagram of a swing arm 21 without a protective cover 21w according to an embodiment of the present invention, to clearly show the internal components of the swing arm 21 and the connection relationship between the components. The drive motor 21b is located at the midpoint of the length direction of the fixed plate 21a to control the impact of the vibration generated by the drive motor 21b on the cleaning brush 22 and ensure the smooth operation of the cleaning brush 22.

[0067] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0068] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A wafer cleaning apparatus, characterized by comprising: include: Clamping assembly that horizontally clamps and drives the wafer to rotate; A brushing component is located on the side of the clamping component; The brushing assembly includes a swing arm that can swing above the clamping assembly, and the cleaning brush on the swing arm swings along the radial direction of the wafer to brush the wafer. The cleaning brush moves vertically with the swing arm and presses against the wafer surface; the cleaning brush can also rotate around the vertical axis to clean the wafer. The swing arm includes a fixed plate with a mounting base at its end, and a rotating shaft is mounted on the mounting base via an adapter; a ball bearing is mounted on the outer side of the adapter, and a linear bearing is mounted on the inner side of the adapter, with the linear bearing sleeved on the outer circumference of the rotating shaft. At least one follower bearing is also provided on the outer periphery of the rotating shaft, and the outer ring of the follower bearing abuts against the outer periphery wall of the rotating shaft. The mounting base has a sealing ring inside, which covers the outer periphery of the rotating shaft and is located at the bottom of the adapter; the sealing ring is provided with grooves; The adapter is provided with at least one vertical channel; The mounting base is equipped with a vent hole, which is connected to the groove of the sealing ring and to a vacuum source; The groove is connected to the space where the ball bearing, linear bearing and follower bearing are located through vertical channels, so that when the vacuum source is working, a particulate matter suction path is formed from each bearing area through the vertical channels and grooves to the vent. There are multiple follower bearings, which are evenly distributed along the circumference of the rotation axis.

2. The wafer cleaning apparatus of claim 1, wherein The outer peripheral wall of the rotating shaft is provided with a flat portion, and the outer ring of the follower bearing abuts against the flat portion.

3. The wafer cleaning apparatus of claim 2, wherein The mounting base is also equipped with a limiting component inside. The limiting component is located at the bottom of the mounting base and is sleeved on the outer periphery of the rotating shaft. The limiting component is a ring structure with a limiting groove. The insertion ring of the rotating shaft is located in the limiting groove. The limiting component is equipped with a discharge hole, which is connected to the limiting groove for conveying particulate matter outward.

4. The wafer cleaning apparatus of claim 1, wherein The swing arm includes a fixed plate, on which a drive motor is provided. The drive motor transmits power to the rotating shaft, and the cleaning brush is detachably connected to the lower end of the rotating shaft.

5. The wafer cleaning apparatus of claim 1, wherein A gap is provided between the outer edge of the sealing ring and the inner wall of the mounting base, and a gap is provided between the inner edge of the sealing ring and the outer wall of the rotating shaft.

6. The wafer cleaning apparatus of claim 4, wherein A mounting bracket is provided above the fixed plate, and a cylinder is mounted on the mounting bracket; the output end of the cylinder is connected to the rotating shaft through a lifting assembly to drive the rotating shaft to move in the vertical direction. The lifting assembly includes a vertical component and a horizontal component. The vertical component is slidably connected to the mounting base, and the horizontal component is connected to the top of the vertical component and fixed to the top of the rotating shaft. A self-aligning bearing and a spring are provided below the horizontal component, and the self-aligning bearing and spring are sleeved on the outside of the rotating shaft. The self-aligning bearing is located on the upper limit plate, one end of the spring abuts against the lower part of the self-aligning bearing, and the other end abuts against the lower limit plate, which is located on the rotating shaft.

7. The wafer cleaning apparatus of claim 6, wherein A pressing member is provided on the side of the vertical member, and the pressing member extends outward from the side of the vertical member; a pressure sensor is provided below the pressing member to monitor the load applied by the cylinder to the cleaning brush.

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