Wafer scrubbing apparatus and wafer scrubbing method

Abstract

The application discloses a wafer brushing device and a wafer brushing method, and belongs to the technical field of semiconductor manufacturing equipment. The wafer brushing device comprises a box body, a supporting assembly arranged in the box body and comprising a driving wheel and a driven wheel, a cleaning brush horizontally arranged in the box body and rotating around an axis to brush the wafer, and a ring-shaped gasket arranged in the driven wheel and made of a hard corrosion-resistant material. An outer peripheral wall of the gasket is provided with a groove for clamping the edge of the wafer. The gasket is provided with liquid discharge holes which are uniformly distributed in the circumferential direction and communicate with the groove to discharge the contaminants in the groove.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing technology, and in particular to a wafer brushing apparatus and a wafer brushing method. 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 chip design, wafer fabrication, wafer processing, electrical measurement, dicing, packaging, and testing. Among these, chemical mechanical polishing (CMP) is a wafer fabrication process, a globally planarizing ultra-precision surface processing technology.

[0003] After chemical mechanical polishing (CMP), wafers require post-processing such as cleaning and drying to prevent contamination of semiconductor devices by trace ions and metal particles, thus ensuring the performance and yield of the semiconductor devices. Wafer cleaning methods include roller brush cleaning and megasonic cleaning, among which roller brush cleaning is more widely used, but it also has some drawbacks.

[0004] During the brush cleaning process, a pair of driving wheels and driven wheels form a support assembly to vertically support and drive the wafer to rotate. The driven wheel is located between the pair of driving wheels, and a speed measuring module is usually installed at the end of the driven wheel to indirectly detect the rotation status of the wafer by the rotation speed of the driven wheel.

[0005] The driven wheel is usually equipped with a washer. The outer peripheral wall of the washer has a groove that engages with the edge of the wafer. During use, this groove may wear or deform, which will affect the friction between the washer and the wafer, causing the driven wheel to slow down and frequently triggering an alarm, thus affecting the stability of the wafer washing module.

[0006] In addition, during the wafer cleaning process, contaminants can accumulate in the grooves of the gaskets, which can affect the cleaning effect on the wafer edges. Summary of the Invention

[0007] In view of this, embodiments of this application provide a wafer brushing apparatus and a wafer brushing method to at least partially solve the above-mentioned problems.

[0008] According to a first aspect of the embodiments of this application, a wafer brushing apparatus is provided, comprising:

[0009] Box;

[0010] The support assembly, housed within the housing, includes a drive wheel and a driven wheel to vertically support and drive the wafer to rotate;

[0011] A cleaning brush is horizontally positioned in the housing and rotates around its axis to clean the wafer;

[0012] The driven wheel has an annular washer inside, which is made of a hard, corrosion-resistant material; the outer peripheral wall of the washer is provided with a groove for engaging the edge of the wafer.

[0013] The gasket is provided with drainage holes that are evenly distributed circumferentially and communicate with the groove to drain contaminants from the groove.

[0014] In some embodiments, the number of drainage holes is multiple, which are disposed on the first sidewall and the second sidewall of the gasket.

[0015] In some embodiments, the washer is provided with an annular groove communicating with the groove, and the annular groove is located inside the groove.

[0016] In some embodiments, the drain hole is a circular hole and / or an elliptical hole, which is disposed through the side wall where the annular groove is located.

[0017] In some embodiments, the drainage holes of the first sidewall and the drainage holes of the second sidewall at least partially overlap.

[0018] In some embodiments, the first and second inner sidewalls of the groove are configured with a textured structure to enhance the reliability of wafer snap-in.

[0019] In some embodiments, the texture structure is an uneven structure that is uniformly distributed along the circumference of the washer; the texture structure includes a plurality of protrusions spaced apart, with adjacent protrusions forming a recess.

[0020] In some embodiments, the recess is a straight groove or an oblique groove, and its longitudinal section is rectangular or trapezoidal.

[0021] In some embodiments, the gasket is made of polyetheretherketone, polyphenylene sulfide, or polytetrafluoroethylene.

[0022] According to a second aspect of the embodiments of this application, a wafer brushing method is provided, which uses the wafer brushing apparatus described above, including:

[0023] The wafer to be cleaned is placed on the support assembly of the cabinet, and the drive wheel drives the wafer to rotate around the axis;

[0024] The spray bar sprays chemical liquid and / or deionized water toward the wafer surface;

[0025] The cleaning brush moves relative to the wafer surface and rotates around the axis to clean the wafer surface.

[0026] During the washing process, the groove of the washer of the driven wheel engages with the edge of the wafer to drive the driven wheel to rotate. The speed of the wafer is then measured by the speed measuring module configured on the driven wheel. The rotating driven wheel drives the washer to rotate so that the contaminants in the groove can be discharged through the drain hole.

[0027] The beneficial effects of this invention include:

[0028] a. In the provided wafer cleaning device, the driven wheel / driving wheel has an internal washer, the outer periphery of which is provided with a groove for engaging the wafer, and the washer is provided with a drain hole to drain the liquid containing particulate matter accumulated in the groove, so as to prevent contaminants from re-adhering to the edge of the wafer and affecting the cleaning effect of the wafer.

[0029] b. There are multiple drain holes, which are evenly distributed along the circumference of the gasket to improve the efficiency of liquid discharge.

[0030] c. The drain hole on the first sidewall of the gasket and the drain hole on the second sidewall of the gasket at least partially overlap, so that at least some liquid remains in the groove, in order to ensure that a liquid film is formed between the textured structure on the gasket and the wafer, so as to balance the coefficient of friction between the two.

[0031] d. The textured structure on the inner wall of the groove includes multiple protrusions spaced apart, and adjacent protrusions form a recess. The recess is a straight groove or an oblique groove, which is conducive to piercing the liquid film formed in the groove, thereby timely draining the liquid in the gasket and avoiding contaminants containing particulate matter from re-adhering to the wafer surface and forming secondary pollution.

[0032] e. The protrusions on the first inner sidewall and the second inner sidewall of the groove of the gasket are staggered in the circumferential direction, and the opposite protrusions partially overlap. This arrangement is conducive to the drainage of small amounts of liquid accumulated inside the gasket.

[0033] f. The first washer and the second washer are provided with an annular groove, which is concentrically arranged on the side of the first washer and the second washer. The annular groove is connected to the recess, and the depth of the annular groove is greater than the depth of the recess, so that liquid containing particulate matter that enters the groove through the recess can be gathered in the annular groove and then concentrated and drawn to the outside of the washer.

[0034] g. The gaskets are made of polyetheretherketone, polyphenylene sulfide, polytetrafluoroethylene, polyoxymethylene, or polyvinylidene fluoride to enhance the gaskets' acid and alkali resistance, inhibit gasket aging, and extend the gaskets' service life. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings.

[0036] Figure 1 This is a schematic diagram of a wafer brushing apparatus provided in an embodiment of this application;

[0037] Figure 2 This is a schematic diagram of a driven wheel provided in an embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of a washer provided in an embodiment of the present invention;

[0039] Figure 4 yes Figure 3 A magnified view of a section at point A in the middle;

[0040] Figure 5 This is a schematic diagram of the split structure of a gasket provided in an embodiment of the present invention;

[0041] Figure 6 This is a schematic diagram of the protrusions and recesses corresponding to a washer provided in an embodiment of the present invention;

[0042] Figure 7 This is a schematic diagram of one of the split structures of a gasket provided in an embodiment of the present invention;

[0043] Figure 8 This is a schematic diagram showing the positional relationship of the protrusions of the first washer and the second washer provided in an embodiment of the present invention;

[0044] Figure 9 This is a partial longitudinal sectional view of a gasket provided in an embodiment of the present invention;

[0045] Figure 10 This is a partial longitudinal sectional view of a gasket provided in another embodiment of the present invention;

[0046] Figure 11 This is a partial longitudinal sectional view of a gasket provided in another embodiment of the present invention;

[0047] Figure 12 This is a schematic diagram of a first gasket with a drain hole provided in an embodiment of the present invention;

[0048] Figure 13 This is a flowchart of a wafer brushing method provided in an embodiment of the present invention;

[0049] Figure 14 This is a schematic diagram of a gasket vertically supporting a wafer in existing technology;

[0050] Figure 15 This is a schematic diagram of a first gasket with a drain hole provided in an embodiment of the present invention. Detailed Implementation

[0051] To enable those skilled in the art to better understand the technical solutions in the embodiments of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art should fall within the protection scope of the embodiments of this application.

[0052] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0053] It should be understood that although the terms "first," "second," "third," etc., may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, without departing from the scope of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0054] Figure 1 This is a schematic diagram of a wafer cleaning device 100 provided in an embodiment of the present invention. The wafer cleaning device 100 includes a housing 10, a support assembly, and a cleaning brush 20, which are disposed in the housing 10.

[0055] The housing 10 is a roughly rectangular shell structure with an opening at the top. The handling robot places the wafer W to be cleaned inside the housing 10 or transfers the cleaned wafer W to the outside of the housing 10 through the opening.

[0056] The cleaning brush 20 is equipped with a drive motor, which is located on the outside of the housing 10. Its output shaft is connected to the cleaning brush 20 to drive the cleaning brush 20 to rotate around its axis. A spray bar 50 is provided on the upper part of the tank 10 to spray DIW and / or cleaning fluid onto the wafer W.

[0057] exist Figure 1 In the illustrated embodiment, a support assembly is disposed inside the housing 10 for rotatably and vertically supporting the wafer W to be cleaned. The support assembly includes a drive wheel 30 and a driven wheel 40, each with a groove along its outer periphery. Two drive wheels 30 are symmetrically arranged on either side of the driven wheel 40, and are positioned along the outer contour of the wafer W, such that the outer edge of the wafer W abuts the bottom surface of the groove. Driven by the drive wheel 30, the vertically positioned wafer W rotates around its axis. A speed sensor (not shown) is mounted on the driven wheel 40 to detect the wafer's rotational speed during the cleaning process and monitor the wafer cleaning status.

[0058] During wafer cleaning, a pair of drive wheels 30 rotate under the drive of a motor (not shown). Under the action of friction, the wafer W, which is vertically positioned in the slots of the drive wheels 30, rotates around the wafer's axis. The cleaning brush 20 abuts against the surface of the wafer W and rotates around its axis.

[0059] The cleaning brush 20 can be made of a porous material such as polyvinyl alcohol. The cleaning brush 20 can absorb a large amount of cleaning fluid used to clean the surface of the wafer W. Before wafer cleaning, liquid needs to be introduced into the cleaning brush 20 to soften it. The rolling cleaning brush 20 contacts the rotating wafer W to remove contaminants from the surface of the wafer W.

[0060] Figure 2 This is a schematic diagram of a driven wheel 40 provided in an embodiment of the present invention. The driven wheel 40 includes a front cover plate 41, a rear cover plate 42, and a washer 43. The washer 43 is concentrically engaged between the front cover plate 41 and the rear cover plate 42. The outer peripheral wall of the washer 43 is provided with a groove 431 to engage the edge of the wafer.

[0061] In this invention, since wafer cleaning requires strong acidic and alkaline chemical solutions, the gasket 43 is corrosion-resistant. That is, the gasket 43 has the characteristic of being resistant to corrosion and deformation; it can withstand prolonged immersion in the required acid / alkali environment without deformation or with deformation within permissible limits.

[0062] Meanwhile, the gasket 43 is also resistant to infrared spectral irradiation, meaning that the shape of the gasket 43 will not deform after long-term infrared spectral irradiation.

[0063] In addition, metal ions may be introduced during the manufacturing process of gasket 43. For example, during the molding process of gasket 43, a mold made of metal material may be used. During the molding process of gasket 43, a small amount of metal ions will enter the interior of gasket 43. During the use of gasket 43, the metal ions will move to the wafer surface, causing metal ion contamination of the wafer.

[0064] Understandably, gasket 43 also needs to have good wear resistance. That is, it should not wear and deform due to the squeezing and friction of the wafer during long-term use.

[0065] The above discussion outlines the design and manufacturing requirements for gasket 43. In actual use, gasket 43 may experience wear or deformation, which can affect the liquid film between the inner wall of gasket 43 and the wafer. Figure 14 The adhesion force (shown) reduces the friction between the washer 43 and the wafer, causing the driven wheel 40 to slow down and frequently trigger an alarm.

[0066] To address the aforementioned technical problems, the inner wall of the groove 431 of the gasket 43 provided by this invention is configured with a textured structure to increase the friction between the gasket 43 and the wafer, thereby enhancing the reliability of wafer bonding. Specifically, the interior of the groove 431 has a first inner wall 431a and a second inner wall 431b. Figure 9 (As shown), both are arranged opposite each other and both are equipped with textured structures. The side of the wafer contacts the textured structure of the inner wall of the groove 431 to increase the friction between them. In this invention, the textured structure provided on the inner wall of the groove 431 is a concave-convex structure, which is evenly distributed along the circumference of the washer 43 to ensure that the force applied to the washer 43 at various positions in the circumference of the wafer is balanced, so as to accurately reflect the rotation of the wafer by the rotation state of the driven wheel 40.

[0067] In this invention, the rotating wafer contacts the convex portion of the textured structure, which changes the interaction mechanism between the wafer and the gasket in existing technologies, effectively avoiding the problem of the rotating wafer slowing down. Specifically, in existing technologies, the wafer is held in a groove on the outer periphery of the gasket, and a liquid film fills the space between the wafer and the inner wall of the groove. The adhesive force of the liquid film forms an interaction force between the two, causing the rotating wafer to drive the gasket to rotate, thus monitoring the wafer's rotation status in real time. In this invention, the convex portion of the textured structure of the gasket 43 directly contacts the edge of the wafer, which makes the friction between the two sufficiently large, preventing the rotating wafer from failing to drive the gasket 43 to rotate and causing a speed-down alarm. Figure 3 This is a schematic diagram of a washer 43 provided in an embodiment of the present invention. In order to more clearly show the textured structure of the inner sidewall of the groove 431, a partial section of the washer 43 is cut out to show the specific structure of the inner sidewall corresponding to the groove 431 of the washer 43.

[0068] Specifically, the texture structure includes multiple raised bumps 432 spaced apart, such as Figure 4As shown, adjacent protrusions 432 form recesses 433. That is, the protrusions 432 directly contact the side edge of the wafer to drive the driven wheel 30 to rotate. The recesses 433 formed by adjacent protrusions 432 continue to retain liquid, and the liquid film filling the recesses 433 also forms an adhesive force with the side edge of the wafer, preventing excessive friction between the protrusions 432 and the wafer from damaging the wafer. Furthermore, the recesses 433 can also mitigate the negative impact of wear on the protrusions 432, because the liquid film filling the recesses 433 can strengthen the interaction force between the gasket 43 and the wafer, thereby maintaining the performance of the gasket 43 and appropriately extending its service life.

[0069] In this invention, the washer 43 can be an integral structure, such as... Figure 3 As shown, the same material is used for processing and forming to ensure the consistency of the corresponding characteristics of the gasket 43, especially the elastic deformation characteristics of the gasket 43.

[0070] To facilitate processing and forming, washer 43 can also be adopted as a split structure, such as... Figure 5 As shown, washer 43 includes a first washer 43A and a second washer 43B, with pins and pin holes on their opposite surfaces to be fixed together by pin connection. The pins and pin holes achieve strict alignment between the parts through their geometric shapes, eliminating gaps and enabling precise assembly. At the same time, the pin connection is suitable for dynamic load environments, effectively preventing the disassembly of the separate structure during operation from affecting the wafer cleaning effect.

[0071] In this invention, the pin is a cylindrical structure to limit the radial displacement of the split structure. It is understood that the pin can also be a tapered pin to simultaneously constrain axial and radial displacement, ensuring the stability of the washer 43 during operation.

[0072] Figure 5 In the embodiment shown, the recess 433 is a straight groove, and the center line of the recess 433 passes through the center of the gasket 43 to ensure that the interaction force between the gasket 43 and the wafer is uniform at all positions around the circumference. At the same time, the recess 433 of the straight groove is conducive to puncturing the liquid film formed in the groove 431, thereby timely draining the liquid in the gasket 43 and avoiding contaminants containing particulate matter from re-adhering to the wafer surface and forming secondary pollution.

[0073] In this embodiment, the number of protrusions 432 is 150 to 450, such as Figure 6 As shown, the longitudinal section of the recess 433 is rectangular, the width of the recess 433 is 0.15-2mm, and the depth of the recess 433 is 0.3-2.5mm. That is, in this embodiment, the protrusion 432 is arranged along the radial direction of the washer 43, and the liquid on the surface of the rotating wafer contacts the side of the protrusion 432, increasing the force between the two.

[0074] As Figure 6 In a variation of the embodiment, the longitudinal section of the recess 433 is trapezoidal. For example, the longitudinal section of the recess 433 may be a trapezoid wider at the outer edge and narrower at the inner edge, wherein the bottom width of the recess 433 is 0.5–4 mm and the top width of the recess 433 is 0.3–2 mm; or the longitudinal section of the recess 433 may be a trapezoid narrower at the outer edge and wider at the inner edge, wherein the bottom width of the recess 433 is 0.3–2 mm and the top width of the recess 433 is 0.5–4 mm. It should be noted that the bottom width of the recess 433 refers to the width of the very root of the recess 433.

[0075] Figure 7 This is a schematic diagram of one of the split structures of the washer 43 provided in an embodiment of the present invention. In this embodiment, the recess 433 is an inclined groove, and the line connecting the midpoint of the inner side of the recess 433 and the center of the washer 43 forms an angle θ with the center line of the recess 433. The angle θ is 15 to 65°. Preferably, the angle θ between the line connecting the midpoint of the inner side of the recess 433 and the center of the washer 43 and the center line of the recess 433 is 30 to 45°.

[0076] In this embodiment, the number of recesses 433 formed by the inclined groove is 150 to 450, which are evenly distributed on the inner sidewall of the groove 431; the width of the recesses 433 is 0.15 to 2 mm, and the depth of the recesses 433 is 0.5 to 3 mm. The inclined direction of the recesses 433 is consistent with the rotation direction of the wafer, so that the liquid in the gasket 43 can be smoothly discharged outward along the recesses 433 under the action of centrifugal force.

[0077] In this invention, the protrusions 432 in the groove 431 of the washer 43 can also be arranged in the circumferential direction to form a circumferential recess 433 between adjacent protrusions 432. This arrangement can also achieve the purpose of increasing the friction between the washer 43 and the wafer.

[0078] As a variation of this embodiment, the circumferential protrusion 432 is combined with the radial protrusion 432, such as... Figure 15 As shown, the two types of protrusions 432 are arranged in groups to enhance the friction between the gasket 43 and the wafer. Simultaneously, the junction of the two types of protrusions 432 can change the state of the water film in the gasket 43, facilitating liquid drainage. Therefore, the drain hole 436 of the gasket 43 can be located at the junction of the two types of protrusions 432 to facilitate timely drainage of liquid containing contaminants, preventing contaminant residue from affecting wafer washing. Specifically, the elongated drain hole 436 overlaps with the junction of the two types of protrusions 432 to facilitate the drainage of liquid from the groove 431.

[0079] Figure 15In the illustrated embodiment, the circumferential protrusions 432 are spaced in groups of two, while the radial protrusions 432 are spaced in groups of nine. The drain hole 436 of the first washer 43A spans the junction of the two types of protrusions 432, so that when the liquid in the groove 431 changes direction, it is discharged outwards along the drain hole 436. It is understood that... Figure 15 The protrusion 432 in the embodiment is only schematic. The actual size of the protrusion 432 is smaller, and the number of protrusions 432 is more.

[0080] In this invention, both the first inner wall 431a and the second inner wall 431b of the groove 431 of the washer 43 need to be equipped with corresponding protrusions 432, such as... Figure 8 As shown, adjacent protrusions 432 form a recess 433.

[0081] Figure 8 In (a), the protrusions 432 of the first inner sidewall 431a and the second inner sidewall 431b are arranged opposite to each other, that is, the protrusions 432 are symmetrical along the center line of the thickness direction of the washer 43. The opposite arrangement of the protrusions 432 helps to ensure that the friction force on the side of the wafer is uniform, thereby ensuring the stable rotation of the wafer.

[0082] Figure 8 In (b), the protrusions 432 of the first inner sidewall 431a and the second inner sidewall 431b are arranged in a staggered circumferential manner, with partial overlap between the opposing protrusions 432. This arrangement facilitates the drainage of small amounts of liquid accumulated inside the gasket 43. Preferably, the width of the overlap between the protrusions 432 is 1 / 5 to 1 / 2 of the width of the protrusion 432. In this invention, the staggered circumferential arrangement of the protrusions 432 weakens the stability of the liquid film in the groove 431, making it easier for the protrusions 432 to break the liquid film in the gasket 43, thereby draining contaminants containing particulate matter from the groove 431 and preventing the accumulation of contaminants inside the gasket 43. When the protrusions 432 of the inner sidewalls are arranged in a staggered circumferential manner, the drain hole 436 can better perform its drainage function.

[0083] Figure 9 This is a partial longitudinal sectional view of a gasket 43 provided in an embodiment of the present invention. In this embodiment, the opposing surfaces of the protrusions 432 of the first inner sidewall 431a and the second inner sidewall 431b are parallel to each other to form a placement cavity with a rectangular longitudinal section. A wafer (not shown) is fitted into this placement cavity. It should be noted that the placement cavity here is part of the groove 431, which refers to the gap between the protrusions 432 on the opposing surfaces.

[0084] Furthermore, the opposing surfaces are symmetrically arranged along the centerline of the thickness direction of the washer 43, so that the mass distribution of the driven wheel 40 formed by the washer 43 in the horizontal direction is relatively uniform, and the driven wheel 40 can rotate uniformly with the wafer.

[0085] It should be noted that the lateral width of the placement cavity matches the thickness of the wafer; in some embodiments, the lateral width of the placement cavity can be 0.25 mm smaller than the wafer thickness; in other embodiments, the lateral width of the placement cavity can be 0.1 mm larger than the wafer thickness. That is, the lateral width of the placement cavity is from T-0.25 mm to T+0.1 mm, where T is the thickness of the wafer.

[0086] Figure 10 yes Figure 9 In a variant of the embodiment, the outer edges of the first inner sidewall 431a and the second inner sidewall 431b of the groove 431 are provided with guide portions 434, which are inclined surfaces to facilitate accurate wafer mounting in the groove 431.

[0087] In this embodiment, the first washer 431a and the second washer 431b are provided with annular grooves 435. The annular grooves 435 are concentrically arranged on the sides of the first washer 43A and the second washer 43B. The components formed by the first washer 43A and the second washer 43B make the chambers formed by the corresponding annular grooves 435 communicate with the grooves 431.

[0088] Furthermore, the annular groove 435 is connected to the recess 433, and the depth of the annular groove 435 is greater than the depth of the recess 433. This allows liquid containing particulate matter that enters the groove 431 through the recess 433 to converge in the annular groove 435 and then be concentrated and drawn to the outside of the gasket 43. Specifically, the bottom surface of the annular groove 435 is located outside the bottom surface of the recess 433, allowing liquid containing particulate matter to converge towards the annular groove 435 through the recess 433. It should be noted that in this invention, "outer side" and "inner side" are relative to the groove 431 of the gasket 43. The location of the groove 431 is the "inner side," and the sidewall of the gasket 43 away from the groove 431 is the "outer side."

[0089] As one aspect of this embodiment, a vacuum channel can be provided inside the gasket 43 to draw the liquid that has gathered in the annular groove 435 to the outside of the gasket 43.

[0090] When the gasket 43 is made of a flexible material, the annular groove 435 can increase the flexibility of the outer edge of the gasket 43, so that the wafer can be adaptively snapped into the inside of the groove 431.

[0091] Figure 9 In this embodiment, the distance L between the bottom surfaces of the annular grooves 435 is T ± 0.15 mm. It should be noted that the bottom surface of the annular groove 435 refers to the bottom surface of the annular groove 435 of the first washer 43A and the bottom surface of the annular groove 435 of the second washer 43B, and this bottom surface is located inside the first washer 43A and the second washer 43B. Figure 9It can be seen that the distance L between the bottom surfaces of the annular groove 435 is the horizontal distance of the groove structure at the bottom of the groove 431.

[0092] In this invention, the width of the groove 431 is typically 0.5–1 mm, which is suitable for both integral and separate structures of the gasket 43. That is, the wafer W can be inserted to different depths H according to process requirements to maintain the wafer's rotational speed and prevent it from slowing down.

[0093] As an embodiment of the present invention, the gasket 43 is provided with a drain hole 436. Figure 12 As shown, the drain hole 436 is provided through the thickness direction of the first washer 43A and the second washer 43B, and the drain hole 436 is connected to the annular groove 435, which is provided through the groove structure of the lower part (inner side) of the groove 431.

[0094] If the washer 43 adopts an integral structure, the drain hole 436 is provided on the first side wall and the second side wall of the washer 43. Here, the first side wall and the second side wall refer to the outer side wall of the washer 43, that is, the side that abuts and is fixed to the front cover plate 41 and the rear cover plate 42 of the driven wheel 40.

[0095] In some embodiments, the drain hole 436 is an elongated hole, such as... Figure 12 As shown, there are multiple gaskets 43 evenly distributed around the circumference of the gasket 43. The liquid accumulated in the annular groove 435 can be discharged through the drain hole 436 between the gasket 43 and the front cover plate 41 and the rear cover plate 42.

[0096] As one aspect of this embodiment, the drain hole 436 located in the first washer 43A is disposed opposite to the drain hole 436 located in the second washer 43B to facilitate the discharge of liquid.

[0097] It is understandable that the drain holes 436 of the first gasket 43A and the second gasket 43B can also be arranged circumferentially staggered, that is, the drain holes 436 can partially overlap, so as to appropriately delay the discharge of liquid in the groove 431, so that the interior of the groove 433 is filled with liquid, and the liquid film in the groove 433 forms an adhesive force between the liquid film and the wafer, thereby balancing the interaction force between the gasket 43 and the wafer, and preventing the texture structure from making excessive hard contact with the wafer and damaging the device layer on the wafer surface.

[0098] Understandable, Figure 9 The guide portion 434 shown can also be an arc surface, which can also allow the wafer to be quickly inserted into the groove 431 of the washer 43.

[0099] Figure 11 yes Figure 10In a variant of the embodiment, the outer edges of the first inner wall 431a and the second inner wall 431b of the groove 431 are provided with two guide portions 434, namely the first guide portion 434a and the second guide portion 434b, both of which are inclined surfaces, wherein the first guide portion 434a is located on the outside of the washer 43.

[0100] Furthermore, the included angle formed by the first guide portion 434a corresponding to the first gasket 43A and the second gasket 43B is greater than the included angle formed by the second guide portion 434b, so that the wafer can quickly enter the gasket 43 via the first guide portion 434a.

[0101] In some embodiments, the lateral width Wh1 of the outer end of the second guide portion 434b can be 0.1 mm larger than the thickness of the wafer. Similarly, the lateral width Wh1 of the outer end of the second guide portion 434b can be 0.15 mm smaller than the thickness of the wafer. The lateral width Wh2 of the inner end of the second guide portion 434b can be 0.2 to 0.45 mm smaller than the thickness of the wafer.

[0102] Figure 11 In the illustrated embodiment, when the lateral width Wh1 of the outer end of the second guide portion 434b is greater than the thickness of the wafer, and the lateral width Wh2 of the inner end of the second guide portion 434b is less than the thickness of the wafer, the process surface of the wafer edge contacts the second guide portion 434b, and the textured structure configured in the groove 431 of the washer 43 can increase its friction with the wafer. During wafer cleaning, the cleaning brushes 20 located on both sides of the wafer twist the wafer, and the wafer is subjected to the downward pressure of the cleaning brushes 20 to force the washer 43 to deform, so that the wafer is inserted deeper into the groove 431. The wafer is reliably inserted into the washer 43 of the driven wheel 40 to prevent the wafer from slipping in the groove 431 of the washer 43, which would cause the wafer rotation speed to decrease.

[0103] When the lateral width Wh1 of the outer end of the second guide portion 434b is less than the thickness of the wafer, as described above, the wafer being cleaned is subjected to the downward pressure of the cleaning brush 20, which forces the gasket 43 to deform, so that the wafer is inserted into the groove 431 with a textured structure on the inner sidewall, thereby increasing the friction between the wafer and the gasket 43 and effectively preventing the wafer from slowing down during the cleaning process.

[0104] Figure 11In the illustrated embodiment, the depth H of the wafer W inserted into the gasket 43, the lateral width Wh1 of the outer end of the second guide portion 434b, and the lateral width Wh2 of the inner end of the second guide portion 434b are crucial. A reasonable combination of these parameters can be applied to wafers with thicknesses within different tolerance ranges to maintain the wafer rotation speed and avoid wafer speed drops. Specifically, the depth H of the wafer W inserted into the gasket 43 is 0.75 mm, 1 mm, 1.25 mm, and 1.5 mm; the lateral width Wh1 of the outer end of the second guide portion 434b is 0.5–0.9 mm; and the lateral width Wh2 of the inner end of the second guide portion 434b is 0.3–0.7 mm.

[0105] In this invention, the gasket 43 can be made of polyetheretherketone, polyphenylene sulfide, polytetrafluoroethylene, polyoxymethylene or polyvinylidene fluoride to enhance the acid and alkali resistance of the gasket 43, inhibit the aging of the gasket 43, and extend its service life.

[0106] It should be noted that in the wafer cleaning device provided by the present invention, the inside of the drive wheel 30 can also be equipped with a washer 43, and the structure and features of the washer 43 are the same as or similar to the structure and features of the washer 43 configured in the driven wheel 40, so as to maintain the rotation speed of the wafer and ensure a good cleaning effect.

[0107] If the washer 43 of the present invention is applied to the drive wheel 30, the wafer to be cleaned needs to be engaged at the bottom of the groove 431 of the washer 43, that is, the edge (arc-shaped part) of the wafer is in contact with the bottom surface of the groove 431; while when the washer 43 is applied to the driven wheel 40, the edge of the wafer needs to be reserved at a certain distance from the bottom surface of the groove 431 to prevent the driven wheel 40 from acting on the wafer and pushing the wafer upward, which would seriously affect the smooth rotation of the wafer.

[0108] Furthermore, the present invention also provides a wafer cleaning method, which uses the above... Figure 1 The wafer brushing apparatus 100 shown has a flowchart, as follows: Figure 13 As shown, the wafer washing method includes:

[0109] The wafer to be cleaned is placed in the support assembly of the housing 10, and the drive wheel 30 drives the wafer to rotate around the axis.

[0110] Spray bar 50 sprays chemical liquid and / or deionized water toward the wafer surface;

[0111] The cleaning brush 20 moves relative to the wafer surface and rotates around the axis to clean the wafer surface.

[0112] During the wafer washing process, the groove 431 of the washer 43 of the driven wheel 40 engages with the edge of the wafer to drive the driven wheel 40 to rotate, and then the speed of the wafer is measured by the speed measuring module configured on the driven wheel 40.

[0113] In this invention, the driven wheel 40 is equipped with a washer 43, and the outer periphery of the washer 43 is provided with a groove 431 for engaging the wafer. The washer 43 is also provided with a drain hole 436 to drain the liquid containing particulate matter accumulated in the groove 431, so as to prevent contaminants from re-adhering to the edge of the wafer and affecting the wafer cleaning effect.

[0114] Simultaneously, the driven wheel 40 also serves to adjust the position and orientation of the rotating wafer. Specifically, driven by the driving wheel 30, the wafer rotates around its own axis, causing it to oscillate in the vertical plane where the wafer is located, which inevitably affects the wafer cleaning effect. In this invention, the driven wheel 40, especially the textured washer 43, enhances the position and orientation correction of the rotating wafer, allowing the wafer to rotate normally in its plane, thereby obtaining a wafer with a surface cleanliness that meets the process requirements.

[0115] Those skilled in the art will recognize that the units and method steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the embodiments of this application.

[0116] The above embodiments are only used to illustrate the embodiments of this application, and are not intended to limit the embodiments of this application. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the embodiments of this application. Therefore, all equivalent technical solutions also fall within the scope of the embodiments of this application, and the patent protection scope of the embodiments of this application should be defined by the claims.

Claims

1. A wafer scrubbing apparatus, characterized by, include: Box; The support assembly, housed within the housing, includes a drive wheel and a driven wheel to vertically support and drive the wafer to rotate; A cleaning brush is horizontally positioned in the housing and rotates around its axis to clean the wafer; The driven wheel has an annular washer inside, which is made of a hard, corrosion-resistant material; the outer peripheral wall of the washer is provided with a groove for engaging the edge of the wafer. The gasket is provided with drainage holes, which are evenly distributed circumferentially and communicate with the groove to drain contaminants in the groove; there are multiple drainage holes, which are provided on the first sidewall and the second sidewall of the gasket. The washer is provided with an annular groove that communicates with the groove, and the annular groove is located inside the groove. The drain hole is a circular hole and / or an elliptical hole, which is disposed through the side wall of the annular groove. The drainage holes of the first sidewall and the drainage holes of the second sidewall at least partially overlap.

2. The wafer brushing apparatus of claim 1, wherein The first and second inner sidewalls of the groove are configured with a textured structure to enhance the reliability of wafer snap-in.

3. The wafer brushing apparatus of claim 2, wherein The texture structure is a concave-convex structure, which is evenly distributed along the circumference of the washer; the texture structure includes multiple protrusions spaced apart, with adjacent protrusions forming concave portions.

4. The wafer brushing apparatus of claim 3, wherein The recess is a straight groove or an oblique groove, and its longitudinal section is rectangular or trapezoidal.

5. The wafer brushing apparatus of claim 1, wherein, The gasket is made of polyetheretherketone, polyphenylene sulfide, or polytetrafluoroethylene.

6. A wafer washing method, characterized in that, Using the wafer brushing apparatus according to any one of claims 1-5, comprising: The wafer to be cleaned is placed on the support assembly of the cabinet, and the drive wheel drives the wafer to rotate around the axis; The spray bar sprays chemical liquid and / or deionized water toward the wafer surface; The cleaning brush moves relative to the wafer surface and rotates around the axis to clean the wafer surface. During the washing process, the groove of the washer of the driven wheel engages with the edge of the wafer to drive the driven wheel to rotate. The speed of the wafer is then measured by the speed measuring module configured on the driven wheel. The rotating driven wheel drives the washer to rotate so that the contaminants in the groove can be discharged through the drain hole.

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