Wafer scrubbing device and wafer scrubbing method

Abstract

The invention discloses a wafer scrubbing device and a wafer scrubbing method. The wafer scrubbing device comprises a box body, a driving device and a driving device, the supporting assembly is arranged in the box body, comprises a driving wheel and a driven wheel, and is used for vertically supporting and driving the wafer to rotate; the cleaning brush is horizontally arranged in the box body and rotates around the axis so as to brush the wafer; an annular gasket is arranged in the driven wheel and is made of a hard corrosion-resistant material; a groove is formed in the peripheral wall of the gasket and is used for clamping the edge of the wafer; and the gasket is provided with liquid discharge holes which are uniformly distributed along the circumferential direction and are communicated with the groove so as to discharge pollutants in the groove.

Description

Technical Field

[0001] Embodiments of the present application relate to the field of semiconductor manufacturing technology, and in particular, to a wafer scrubbing device and a wafer scrubbing method. Background Art

[0002] The integrated circuit industry is the core of the information technology industry and plays a key role in boosting the transformation and upgrading of the manufacturing industry to digital and intelligent. A chip is the carrier of an integrated circuit, and chip manufacturing involves chip design, wafer manufacturing, wafer processing, electrical measurement, cutting and packaging, and testing processes. Among them, Chemical Mechanical Planarization (CMP) belongs to the wafer manufacturing process, which is an ultra-precise surface processing technology for global planarization.

[0003] The wafers that have completed chemical mechanical polishing need to be post-processed such as cleaning and drying to avoid the contamination of semiconductor devices by trace ions and metal particles and ensure the performance and qualification rate of semiconductor devices. The wafer cleaning methods include: brush rolling cleaning, megasonic cleaning, etc. Among them, brush rolling cleaning is widely used, but there are also some problems.

[0004] During the brush rolling cleaning process of the wafer, a pair of driving wheels and a driven wheel form a support assembly to vertically support and drive the wafer to rotate. Among them, the driven wheel is arranged between the pair of driving wheels, and a speed measurement module is usually configured at the end of the driven wheel to indirectly detect the rotation state of the wafer through the rotation speed of the driven wheel.

[0005] A washer is usually configured in the driven wheel, and a groove for clamping the edge of the wafer is provided on the outer peripheral wall of the washer. The groove will be worn or deformed during use, which will affect the friction between the washer and the wafer, resulting in the speed reduction of the driven wheel and frequent alarms, and further affecting the stability of the use of the wafer scrubbing module.

[0006] In addition, during the wafer cleaning process, a certain amount of contaminants will accumulate in the groove of the washer, which will affect the cleaning effect of the wafer edge. Summary of the Invention

[0007] In view of this, embodiments of the present application provide a wafer scrubbing device and a wafer scrubbing method to at least partially solve the above problems.

[0008] According to a first aspect of embodiments of the present application, there is provided a wafer scrubbing device, which includes:

[0009] A box body;

[0010] A support assembly, arranged in the box body, which includes a driving wheel and a driven wheel to vertically support and drive the wafer to rotate;

[0011] A cleaning brush is horizontally arranged in a box body and rotates around an axis to brush a wafer.

[0012] A ring-shaped washer is arranged inside the driven wheel and is made of a hard corrosion-resistant material; a groove is arranged on the outer peripheral wall of the washer for clamping the edge of the wafer.

[0013] The washer is provided with drain holes which are evenly distributed circumferentially and communicated with the groove to discharge pollutants in the groove.

[0014] In some embodiments, the number of the drain holes is multiple, and they are arranged on the first side wall and the second side wall of the washer.

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

[0016] In some embodiments, the drain holes are circular holes and / or oval holes, and they penetrate through the side wall where the annular groove is located.

[0017] In some embodiments, at least part of the drain holes on the first side wall overlap with the drain holes on the second side wall.

[0018] In some embodiments, the first inner side wall and the second inner side wall of the groove are provided with a texture structure to enhance the reliability of wafer clamping.

[0019] In some embodiments, the texture structure is a concave-convex structure which is evenly distributed circumferentially along the washer; the texture structure includes a plurality of protrusions distributed at intervals, and concave portions are formed between adjacent protrusions.

[0020] In some embodiments, the concave portions are straight grooves or inclined grooves, and their longitudinal sections are rectangles or trapezoids.

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

[0022] According to the second aspect of the embodiments of the present application, a wafer brushing method is provided, which uses the above-mentioned wafer brushing device, and includes:

[0023] Placing a wafer to be brushed on a support assembly in the box body, and driving the wafer to rotate around an axis by a driving wheel;

[0024] Spraying chemical liquid and / or deionized water towards the surface of the wafer by a spray rod;

[0025] Moving the cleaning brush relatively to abut against the surface of the wafer, and rotating the cleaning brush around the axis to brush the surface of the wafer;

[0026] During the brushing process, the groove of the washer of the driven wheel engages with the edge of the wafer to drive the rotation of the driven wheel, and then the rotation speed of the wafer is measured by a speed measurement module configured on the driven wheel; the rotating driven wheel drives the washer to rotate to discharge the contaminants in the groove through the drain holes.

[0027] The beneficial effects of the present invention include:

[0028] a. In the provided wafer brushing device, the inner washer of the driven wheel / active wheel is provided with a groove on the outer peripheral side for engaging with the wafer, and the washer is provided with drain holes to discharge the liquid containing particles accumulated in the groove, so as to prevent contaminants from adhering to the wafer edge again and affecting the brushing effect of the wafer;

[0029] b. The number of drain holes is multiple, and they are evenly distributed along the circumferential direction of the washer to improve the efficiency of liquid discharge;

[0030] c. The drain holes on the first side wall of the washer and the drain holes on the second side wall of the washer at least partially overlap, so that at least part of the liquid remains in the groove, to ensure that a liquid film is formed between the texture structure on the washer and the wafer to balance the friction coefficients of the two;

[0031] d. The texture structure provided on the inner side wall of the groove includes a plurality of protrusions distributed at intervals, and adjacent protrusions form recesses, and the recesses are straight grooves or inclined grooves, which is beneficial to puncture the liquid film formed in the groove, and then timely discharge the liquid in the washer, to avoid the reattachment of contaminants containing particles to the wafer surface and form secondary pollution;

[0032] e. The protrusions on the first inner side wall and the second inner side wall of the groove of the washer are arranged circumferentially staggered, and there is partial overlap of the opposite protrusions. Such a setting is beneficial to the discharge of a small amount of liquid accumulated inside the washer;

[0033] f. The first washer and the second washer are provided with annular grooves, which are concentrically arranged on the sides of the first washer and the second washer, and the annular grooves are communicated with the recesses. The depth of the annular grooves is greater than the depth of the recesses, so that the liquid containing particles entering the groove through the recesses can converge in the annular grooves and then be centrally sucked to the outside of the washer;

[0034] g. The washer is made of polyether ether ketone, polyphenylene sulfide, polytetrafluoroethylene, polyoxymethylene or polyvinylidene fluoride to enhance the acid and alkali resistance of the washer, inhibit the aging of the washer, and extend the service life of the washer. Description of the Drawings

[0035] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments described in the embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0036] Figure 1 Schematic diagram of a wafer scrubbing device provided by an embodiment of the present application;

[0037] Figure 2 Schematic diagram of a driven wheel provided by an embodiment of the present invention;

[0038] Figure 3 Schematic diagram of a washer provided by an embodiment of the present invention;

[0039] Figure 4 is Figure 3 Partial enlarged view at position A in

[0040] Figure 5 Schematic diagram of the split structure of a washer provided by an embodiment of the present invention;

[0041] Figure 6 Schematic diagram of the protrusions and recesses corresponding to a washer provided by an embodiment of the present invention;

[0042] Figure 7 Schematic diagram of one of the split structures of a washer provided by an embodiment of the present invention;

[0043] Figure 8 Schematic diagram of the positional relationship of the protrusions of the first washer and the second washer provided by an embodiment of the present invention;

[0044] Figure 9 Partial longitudinal sectional view of a washer provided by an embodiment of the present invention;

[0045] Figure 10 Partial longitudinal sectional view of a washer provided by another embodiment of the present invention;

[0046] Figure 11 Partial longitudinal sectional view of a washer provided by still another embodiment of the present invention;

[0047] Figure 12 Schematic diagram of a first washer with a liquid discharge hole provided by an embodiment of the present invention;

[0048] Figure 13 Flowchart of a wafer scrubbing method provided by an embodiment of the present invention;

[0049] Figure 14 Schematic diagram of a washer in the prior art vertically supporting a wafer;

[0050] Figure 15 It is a schematic diagram of a first washer with a liquid discharge hole provided by an embodiment of the present invention. Detailed implementation manners

[0051] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art shall fall within the protection scope of the embodiments of the present application.

[0052] The terms used in the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "the", and "said" used in the present 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" 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 the present application to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more, unless otherwise specifically defined.

[0054] Figure 1 It is a schematic diagram of a wafer scrubbing device 100 provided by an embodiment of the present invention. The wafer scrubbing device 100 includes a box body 10, a support assembly, and a cleaning brush 20. The cleaning brush 20 and the support assembly are arranged in the box body 10.

[0055] Among them, the box body 10 is a substantially rectangular shell structure, and an opening is provided at the top thereof. The handling robot places the wafer W to be cleaned into the interior of the box body 10 or transfers the wafer W that has been cleaned to the outside of the box body 10 through the opening of the box body 10.

[0056] The cleaning brush 20 is configured with a driving motor. The driving motor is arranged outside the box body 10, and 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 at the upper part of the tank body 10 to spray DIW and / or cleaning liquid onto the wafer W.

[0057] In Figure 1 In the illustrated embodiment, the support assembly is disposed inside the box body 10 and is used to vertically and rotatably support the wafer W to be cleaned. The support assembly includes a driving wheel 30 and a driven wheel 40, and the driving wheel 30 and the driven wheel 40 are configured with clamping grooves disposed along the outer peripheral side of the roller body; the number of the driving wheels 30 is two, and they are symmetrically disposed on both sides of the driven wheel 40. The driving wheel 30 and the driven wheel 40 are disposed along the outer contour of the wafer W, such that the outer edge of the wafer W abuts against the bottom surface of the clamping groove; driven by the driving wheel 30, the vertically disposed wafer W rotates around the axis of the wafer. Wherein, a speed measuring sensor (not shown) is configured on the driven wheel 40 to detect the rotation speed of the wafer during the cleaning process and monitor the state of the wafer cleaning.

[0058] During wafer cleaning, a pair of driving wheels 30 rotate driven by a motor (not shown). Under the action of friction, the wafer W disposed vertically in the clamping groove of the driving wheel 30 rotates around the axis of the wafer. The cleaning brush 20 abuts against the surface of the wafer W and rotates around the axis of the cleaning brush 20.

[0059] The cleaning brush 20 can be made of a porous material such as polyvinyl alcohol, and the cleaning brush 20 can adsorb a large amount of cleaning liquid for scrubbing the surface of the wafer W. Before wafer cleaning, it is necessary to introduce liquid into the interior of the cleaning brush 20 to soften the cleaning brush 20, and the rolling cleaning brush 20 contacts the rotating wafer W to remove the contaminants on the surface of the wafer W.

[0060] Figure 2 FIG. is a schematic diagram of the driven wheel 40 provided by 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 clamped between the front cover plate 41 and the rear cover plate 42. A groove 431 is configured on the outer peripheral wall of the washer 43 to clamp the edge of the wafer.

[0061] In the present invention, since strong acid and strong base chemical liquids are required for wafer scrubbing, the washer 43 has corrosion resistance. That is, the washer 43 has the characteristic of corrosion-resistant deformation, and it is soaked in the required acid / alkali environment for a long time without deformation or the deformation is within the allowable range.

[0062] At the same time, the washer 43 can also resist infrared spectrum irradiation, that is, after long-term irradiation by the infrared spectrum, the shape of the washer 43 will not be deformed.

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

[0064] It is understandable that the washer 43 also needs to have good wear resistance. That is, during long-term use, it will not wear and deform due to the extrusion and friction of the wafer.

[0065] The above discussion is the requirement for the design and manufacture of the washer 43. In actual use, the washer 43 may experience wear or deformation, which will affect the adhesion force of the liquid film ( Figure 14 shown) between the inner side wall of the washer 43 and the wafer, thereby reducing the frictional force between the washer 43 and the wafer, causing the driven wheel 40 to decelerate and alarm frequently.

[0066] To solve the above technical problems, the inner side wall of the groove 431 of the washer 43 provided by the present invention is provided with a texture structure to increase the frictional force between the washer 43 and the wafer, thereby enhancing the reliability of wafer clamping. Specifically, the inside of the groove 431 has a first inner side wall 431a and a second inner side wall 431b ( Figure 9 shown), which are oppositely arranged and both are provided with a texture structure. The side surface of the wafer contacts the texture structure of the inner side wall of the groove 431 to increase the frictional force between the two. In the present invention, the texture structure provided on the inner side wall of the groove 431 is a concave-convex structure, which is evenly distributed along the circumferential direction of the washer 43 to ensure that the forces applied to the washer 43 at various positions in the circumferential direction of the wafer are balanced, so as to accurately reflect the rotation condition of the wafer through the rotation state of the driven wheel 40.

[0067] That is, the rotating wafer contacts the convex part of the texture structure, which changes the interaction mechanism between the wafer and the washer in the prior art and effectively avoids the problem of the deceleration of the rotating wafer. Specifically, in the prior art, the wafer is clamped in the groove on the outer periphery of the washer, and there is a liquid film between the inner side wall of the groove and the wafer to form the acting force between the two by using the adhesion force of the liquid film, so that the rotating wafer drives the washer to rotate to monitor the rotation state of the wafer in real time. In the present invention, the convex part of the texture structure of the washer 43 directly contacts the edge of the wafer, which makes the frictional force between the two large enough to avoid the problem that the rotating wafer cannot drive the washer 43 to rotate and cause deceleration alarm. Figure 3 It is a schematic diagram of the washer 43 provided by an embodiment of the present invention. To more clearly show the texture structure arranged on the inner side wall of the groove 431, a part of the washer 43 is specifically cut to show the specific structure of the inner side wall corresponding to the groove 431 of the washer 43.

[0068] Specifically, the texture structure includes a plurality of protrusions 432 distributed at intervals, such as Figure 4As shown, adjacent protrusions 432 form recesses 433. That is, the protrusions 432 directly contact the side surface of the wafer edge to drive the driven wheel 30 to rotate. And the recesses 433 formed by the adjacent protrusions 432 still retain liquid, and the liquid film filled in the recesses 433 will also form an adhesion force with the side surface of the wafer to prevent excessive friction between the protrusions 432 and the wafer from damaging the wafer. In addition, the setting of the recesses 433 can also weaken the negative impact brought by the wear of the protrusions 432, because the liquid film filled in the recesses 433 can strengthen the interaction force between the gasket 43 and the wafer, thereby maintaining the service performance of the gasket 43 and appropriately extending the service life of the gasket 43.

[0069] In the present invention, the gasket 43 can be of an integral structure, such as Figure 3 shown, that is, processed and formed with the same material to ensure the consistency of the corresponding characteristics of the gasket 43, especially the characteristics of elastic deformation of the gasket 43.

[0070] For the convenience of processing and forming, the gasket 43 can also adopt a split structure, such as Figure 5 shown; the gasket 43 includes a first gasket 43A and a second gasket 43B, and pin shafts and pin holes are arranged on the opposite surfaces of the two to be fixed together by pin connection. The pin shafts and pin holes achieve strict alignment between parts through geometric shapes to eliminate gaps, so as to achieve precise assembly of the two; at the same time, pin connection fixation is suitable for the environment of dynamic load, effectively preventing the split structure from disassembling during operation and affecting the cleaning effect of the wafer.

[0071] In the present invention, the pin shaft is of a cylindrical structure to limit the radial displacement of the split structure. It can be understood that the pin shaft can also be a tapered pin to simultaneously constrain the axial and radial displacements and ensure the stability of the operation of the gasket 43.

[0072] Figure 5 In the shown embodiment, 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 forces between all positions of the circumference of the gasket 43 and the wafer are uniform; at the same time, the setting of the straight groove recess 433 is beneficial to puncture the liquid film formed in the groove 431, and then timely discharge the liquid in the gasket 43, avoiding the reattachment of pollutants containing particulate matter to the wafer surface to form secondary pollution.

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

[0074] AsFigure 6 Variant of the embodiment, the longitudinal section of the recess 433 is trapezoidal. If the longitudinal section of the recess 433 is a trapezoid that is wider outside and narrower inside, 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; if the longitudinal section of the recess 433 is a trapezoid that is narrower outside and wider inside, 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 at the root of the recess 433.

[0075] Figure 7 It is a schematic diagram of one of the split structures of the washer 43 provided by an embodiment of the present invention. In this embodiment, the recess 433 is an inclined groove, and the angle θ is formed 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, and this angle θ is 15 - 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 - 45°.

[0076] In this embodiment, the number of recesses 433 formed by the inclined grooves is 150 - 450, and they are evenly distributed on the inner side wall of the groove 431; the width of the recess 433 is 0.15 - 2 mm, and the depth of the recess 433 is 0.5 - 3 mm. Among them, the inclined direction of the recess 433 is consistent with the rotation direction of the wafer, so that the liquid in the washer 43 can smoothly drain out along the recess 433 under the action of centrifugal force.

[0077] In the present invention, the protrusions 432 in the groove 431 of the washer 43 can also be arranged along the circumferential direction to form recesses 433 along the circumferential direction between adjacent protrusions 432. Arranged in this way, the purpose of increasing the friction between the washer 43 and the wafer can also be achieved.

[0078] As a variant of this embodiment, the circumferential protrusions 432 and the radial protrusions 432 are combined with each other, as Figure 15 shown, the two types of protrusions 432 are arranged at intervals in groups to enhance the friction between the washer 43 and the wafer. At the same time, at the junction of the two types of protrusions 432, the state of the water film in the washer 43 can be changed, which is beneficial to the drainage of the liquid. Therefore, the liquid discharge hole 436 of the washer 43 can be arranged at the junction of the two types of protrusions 432 to facilitate the timely discharge of the liquid containing contaminants and avoid the influence of contaminant residues on the wafer cleaning. That is, the long strip-shaped liquid discharge hole 436 overlaps with the junction of the two types of protrusions 432 facing different directions to facilitate the discharge of the liquid in the groove 431.

[0079] Figure 15In the illustrated embodiment, the circumferential protrusions 432 are distributed at intervals in groups of two, while the radial protrusions 432 are distributed at intervals in groups of nine; and the drain holes 436 of the first washer 43A straddle the junction of the protrusions 432 facing two directions, so that when the liquid in the groove 431 changes its flow direction, it is discharged outward along the drain holes 436. It can be understood that Figure 15 The protrusions 432 in the embodiment are only schematically shown, the actual size of the protrusions 432 is smaller, and the number of the protrusions 432 is larger.

[0080] In the present invention, a plurality of corresponding protrusions 432 need to be configured on both the first inner sidewall 431a and the second inner sidewall 431b of the groove 431 of the washer 43, as Figure 8 shown, the adjacent protrusions 432 form a recess 433.

[0081] Figure 8 (a), the protrusions 432 on the first inner sidewall 431a and the second inner sidewall 431b are arranged oppositely, that is, the protrusions 432 are symmetric about the center line in the thickness direction of the washer 43. The opposite arrangement of the protrusions 432 is beneficial to ensuring that the frictional force received by the side surface of the wafer is uniform, and further ensuring the stable rotation of the wafer.

[0082] Figure 8 (b), the protrusions 432 on the first inner sidewall 431a and the second inner sidewall 431b are arranged circumferentially staggered, and there is partial overlap between the opposite protrusions 432. Such an arrangement is beneficial to the discharge of a small amount of liquid accumulated inside the washer 43. Preferably, the overlapping width of the protrusions 432 is 1 / 5 to 1 / 2 of the width of the protrusions 432. In the present invention, the circumferential staggered arrangement of the protrusions 432 weakens the stability of the liquid film in the groove 431, facilitating the protrusions 432 to break the liquid film in the washer 43, and then discharging the pollutants containing particulate matter in the groove 431 to avoid the accumulation of pollutants inside the washer 43. When the protrusions 432 configured on the inner sidewall are circumferentially staggered, the drain holes 436 can play a more effective role in draining liquid.

[0083] Figure 9 is a partial longitudinal sectional view of the washer 43 provided by an embodiment of the present invention. In this embodiment, the opposite surfaces of the protrusions 432 on 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, and a wafer (not shown) is clamped in the placement cavity. It should be noted that the placement cavity here is a part of the groove 431, which refers to the gap between the opposite protrusions 432

[0084] Furthermore, the opposite surfaces are symmetrically arranged about the center line in 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 some 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. Wherein, T is the thickness of the wafer.

[0086] Figure 10 Yes Figure 9 It is a variant of the embodiment. In this embodiment, guiding portions 434 are arranged on the outer edges of the first inner side wall 431a and the second inner side wall 431b of the groove 431. The guiding portions 434 are inclined surfaces to facilitate accurate clamping of the wafer 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 assembly formed by the first washer 43A and the second washer 43B enables the chambers formed by the corresponding annular grooves 435 to communicate with the groove 431.

[0088] Furthermore, the annular groove 435 communicates with the recess 433. The depth of the annular groove 435 is greater than the depth of the recess 433, so that the liquid containing particulate matter entering the groove 431 via the recess 433 can converge in the annular groove 435 and then be centrally sucked to the outside of the washer 43. Specifically, the bottom surface of the annular groove 435 is located outside the bottom surface of the recess 433, so that the liquid containing particulate matter converges towards the annular groove 435 via the recess 433. It should be noted that in the present invention, "outside" and "inside" are relative to the groove 431 of the washer 43. The position where the groove 431 is located is "inside", and the side wall of the washer 43 away from the groove 431 is "outside".

[0089] As an aspect of this embodiment, a vacuum channel can be provided inside the washer 43 to suck the liquid converging in the annular groove 435 to the outside of the washer 43.

[0090] When the washer 43 is made of a flexible material, the arrangement of the annular groove 435 can increase the flexibility of the outer edge of the washer 43, enabling the wafer to be adaptively clamped inside the groove 431.

[0091] Figure 9 In the 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. This bottom surface is located inside the first washer 43A and the second washer 43B. Figure 9It can be known that the distance L between the bottom surfaces of the annular grooves 435 is the horizontal distance of the groove structure at the lower part of the groove 431.

[0092] In the present invention, the width of the groove 431 is generally 0.5 - 1 mm, and this width is applicable to both the integral structure and the split structure of the gasket 43. That is, the wafer W can be inserted to different depths H according to process requirements to maintain the rotation speed of the wafer and avoid the reduction of the wafer speed.

[0093] As an embodiment of the present invention, the gasket 43 is configured with drain holes 436 ( Figure 12 shown), the drain holes 436 are arranged through the gasket 43 along the thickness direction of the first gasket 43A and the second gasket 43B, and the drain holes 436 are communicated with the annular grooves 435, and are arranged through the groove structure at the lower part (inner side) of the groove 431.

[0094] If the gasket 43 adopts an integral structure, the drain holes 436 are arranged on the first side wall and the second side wall of the gasket 43. Here, the first side wall and the second side wall refer to the outer side walls of the gasket 43, that is, the sides that are in contact and fixed with the front cover plate 41 and the rear cover plate 42 of the driven wheel 40.

[0095] In some embodiments, the drain holes 436 are long strip holes, as Figure 12 shown, and the number of them is multiple and they are evenly distributed along the circumferential direction of the gasket 43. The liquid accumulated in the annular groove 435 can be discharged to the space between the gasket 43 and the front cover plate 41 and the rear cover plate 42 through the drain holes 436.

[0096] As an aspect of this embodiment, the drain holes 436 located in the first gasket 43A and the drain holes 436 located in the second gasket 43B are arranged opposite to each other to facilitate the discharge of liquid.

[0097] It can be understood that the drain holes 436 of the first gasket 43A and the second gasket 43B can also be arranged in a circumferential staggered manner, that is, the drain holes 436 can partially overlap, so as to appropriately delay the discharge of the liquid in the groove 431, so that the inside of the recess 433 is filled with liquid, and the liquid film adhesion force is formed between the liquid film in the recess 433 and the wafer, thereby balancing the interaction force between the gasket 43 and the wafer, and preventing the texture structure from contacting the wafer surface device layer too rigidly and damaging it.

[0098] It can be understood that, Figure 9 the guiding part 434 shown can also be an arc surface, which can also enable the wafer to be quickly inserted into the groove 431 of the gasket 43.

[0099] Figure 11 is Figure 10Variant of the embodiment in which two guiding portions 434, namely a first guiding portion 434a and a second guiding portion 434b, both of which are inclined surfaces, are arranged at the outer edges of the first inner sidewall 431a and the second inner sidewall 431b of the groove 431, and the first guiding portion 434a is located outside the washer 43.

[0100] Furthermore, the included angle formed by the first guiding portions 434a corresponding to the first washer 43A and the second washer 43B is greater than the included angle formed by the second guiding portions 434b, so that the wafer can quickly enter the washer 43 through the first guiding portions 434a.

[0101] In some embodiments, the lateral width Wh1 of the outer end of the second guiding portion 434b may be 0.1 mm larger than the thickness of the wafer. Similarly, the lateral width Wh1 of the outer end of the second guiding portion 434b may also be 0.15 mm smaller than the thickness of the wafer; the lateral width Wh2 of the inner end of the second guiding portion 434b may be 0.2 - 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 guiding portion 434b is greater than the thickness of the wafer and the lateral width Wh2 of the inner end of the second guiding portion 434b is smaller than the thickness of the wafer, the process surface at the edge of the wafer contacts the second guiding portion 434b, and the texture structure arranged in the groove 431 of the washer 43 can increase the friction between it and the wafer. When the wafer is cleaned, the cleaning brushes 20 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, and 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 and causing the rotation speed of the wafer to decrease.

[0103] When the lateral width Wh1 of the outer end of the second guiding portion 434b is smaller than the thickness of the wafer, as described above, the cleaned 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 into the groove 431 with a texture structure on the inner sidewall to increase the friction between the wafer and the washer 43, thereby effectively preventing the wafer from losing speed during the cleaning process.

[0104] Figure 11In the illustrated embodiment, the depth H at which the wafer W is inserted into the washer 43, the lateral width Wh1 at the outer end of the second guiding portion 434b, and the lateral width Wh2 at the inner end of the second guiding portion 434b are crucial. A reasonable combination of the above parameters can accommodate wafers with different thickness tolerances to maintain the rotational speed of the wafer and avoid the problem of the wafer losing speed. Among them, the depth H at which the wafer W is inserted into the washer 43 is 0.75 mm, 1 mm, 1.25 mm, and 1.5 mm, the lateral width Wh1 at the outer end of the second guiding portion 434b is 0.5 - 0.9 mm, and the lateral width Wh2 at the inner end of the second guiding portion 434b is 0.3 - 0.7 mm.

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

[0106] It should be noted that in the wafer scrubbing device provided by the present invention, a washer 43 can also be configured inside the driving wheel 30, and the structure and characteristics of the washer 43 are the same as or similar to those of the washer 43 configured in the driven wheel 40 to maintain the rotational speed of the wafer and ensure a good scrubbing effect.

[0107] If the washer 43 of the present invention is applied to the driving wheel 30, the wafer to be cleaned needs to be clamped at the bottom of the groove 431 of the washer 43, that is, the edge (arc portion) of the wafer contacts the bottom surface of the groove 431; when the washer 43 is applied to the driven wheel 40, a certain distance needs to be reserved between the edge of the wafer and the bottom surface of the groove 431 to prevent the driven wheel 40 from acting on the wafer and lifting the wafer upward, which will seriously affect the smooth rotation of the wafer.

[0108] In addition, the present invention also provides a wafer scrubbing method, which uses the wafer scrubbing device 100 shown above Figure 1 The flowchart of which is as shown in Figure 13 This wafer scrubbing method includes:

[0109] Placing the wafer to be scrubbed on the support assembly of the box body 10, and the driving wheel 30 drives the wafer to rotate around the axis;

[0110] The spray bar 50 sprays chemical liquid and / or deionized water towards the surface of the wafer;

[0111] The cleaning brush 20 moves relatively to abut against the surface of the wafer, and the cleaning brush 20 rotates around the axis to scrub the surface of the wafer;

[0112] During the wafer scrubbing process, the groove 431 of the washer 43 of the driven wheel 40 clamps the edge of the wafer to drive the driven wheel 40 to rotate, and then the rotational speed of the wafer is measured by the speed measurement module configured on the driven wheel 40.

[0113] In the present invention, a washer 43 is disposed on the driven wheel 40. A groove 431 for clamping a wafer is disposed on the outer peripheral side of the washer 43. The washer 43 is provided with a liquid discharge hole 436 to discharge the liquid containing particulate matter accumulated in the groove 431, so as to prevent contaminants from adhering to the wafer edge again and affecting the brushing effect of the wafer.

[0114] Meanwhile, the driven wheel 40 also functions to adjust the posture of the rotating wafer. Specifically, driven by the driving wheel 30, the wafer rotates around its own axis, and it will swing in the vertical plane where the wafer is located, which will inevitably affect the cleaning effect of the wafer. In the present invention, the setting of the driven wheel 40, especially the setting of the washer 43 with a texture structure, can enhance the posture correction of the rotating wafer, enable the wafer to rotate normally in its plane, and thus obtain a wafer with a surface cleanliness meeting the process requirements.

[0115] Those of ordinary skill in the art can realize that the units and method steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the embodiments of this application.

[0116] The above embodiments are only used to illustrate the embodiments of this application, rather than to limit the embodiments of this application. Those of ordinary skill in the relevant technical field can also make various changes and modifications without departing from the spirit and scope of the embodiments of this application. Therefore, all equivalent technical solutions also belong to the scope of the embodiments of this application. The patent protection scope of the embodiments of this application shall be defined by the claims.

Claims

1. A wafer scrubbing device, characterized in that: include: Box; A support assembly is disposed in the box body, and includes a driving wheel and a driven wheel to vertically support and drive the wafer to rotate; A cleaning brush is horizontally arranged in the box and rotates around an axis to clean the wafer; An annular gasket is arranged inside the driven wheel and is made of a hard corrosion-resistant material; a groove is arranged on the outer peripheral wall of the gasket for clamping the edge of the wafer; The gasket is provided with drainage holes which are evenly distributed along the circumference and communicated with the groove to discharge pollutants in the groove.

2. The wafer scrubbing device according to claim 1, characterized in that: There are multiple drainage holes, which are arranged on the first side wall and the second side wall of the gasket.

3. The wafer scrubbing device according to claim 2, characterized in that: The gasket is provided with an annular groove which is in communication with the groove, and the annular groove is located inside the groove.

4. The wafer scrubbing device according to claim 3, characterized in that: The drainage hole is a circular hole and / or an elliptical hole, which is arranged through the side wall where the annular groove is located.

5. The wafer scrubbing device according to claim 3, characterized in that: The drainage hole of the first side wall at least partially overlaps with the drainage hole of the second side wall.

6. The wafer scrubbing device according to claim 1, characterized in that: The first inner side wall and the second inner side wall of the groove are configured with a texture structure to enhance the reliability of wafer clamping.

7. The wafer scrubbing device according to claim 6, characterized in that: The texture structure is a concave-convex structure, which is evenly distributed along the circumference of the gasket; the texture structure includes a plurality of protrusions distributed at intervals, and adjacent protrusions form concave portions.

8. The wafer scrubbing device according to claim 7, characterized in that: The recessed portion is a straight groove or an oblique groove, and its longitudinal section is a rectangle or a trapezoid.

9. The wafer scrubbing device according to claim 1, characterized in that: The gasket is made of polyetheretherketone, polyphenylene sulfide or polytetrafluoroethylene.

10. A wafer scrubbing method, characterized in that: The wafer scrubbing device according to any one of claims 1 to 9 comprises: The wafer to be cleaned is placed on the supporting assembly of the box, and the driving 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 relatively to abut against the surface of the wafer, and the cleaning brush rotates around the axis to brush the surface of the wafer; During the scrubbing process, the groove of the gasket of the driven wheel engages the edge of the wafer to drive the driven wheel to rotate, and then the speed of the wafer is measured by a speed measuring module configured on the driven wheel; the rotating driven wheel drives the gasket to rotate to discharge contaminants in the groove through the drainage hole.

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