Wafer cleaning method

Abstract

The invention discloses a wafer cleaning method which comprises the steps that S1, a wafer is placed in a roller assembly in a groove body, and the roller assembly vertically supports the wafer to be cleaned; s2, water flows through a cleaning brush in the tank body, the cleaning brush moves towards the wafer to a cleaning position, and the cleaning brush rolls to clean the surface of the wafer in a contact mode; and S3, the cleaning brush completing brushing is far away from the wafer, and the cleaning piece in the groove body sprays fluid towards the roller assembly so as to flush particulate matter accumulated on the roller assembly.

Description

[0001] This application is a divisional application of the invention patent application with application number 2022109722703 filed on August 15, 2022. Technical Field

[0002] The present invention belongs to the technical field of wafer post-processing, and in particular relates to a wafer cleaning method. Background Art

[0003] Chemical Mechanical Polishing (CMP), one of the five core processes in wafer manufacturing, is a technology that achieves global wafer flatness. After CMP, a large amount of particulate matter remains on the wafer surface, necessitating post-processing such as cleaning and drying.

[0004] IC manufacturing processes are carried out in clean rooms using a variety of organic and inorganic substances. Due to the influence of personnel, the environment, and other factors, a large amount of contaminants are generated during wafer processing. These contaminants range in particle size from a few nanometers to several hundred nanometers. Wafer cleaning is designed to remove contaminants attached to the wafer surface and control the size and number of contaminants on the wafer surface within process requirements.

[0005] Wafer cleaning methods generally include: roller brush cleaning, megasonic cleaning, etc. Among them, roller brush cleaning is more widely used. The existing wafer cleaning device can be used for vertical roller brush cleaning of wafers. The wafer cleaning device includes a tank body, and a roller assembly is arranged inside the tank body. The roller assembly includes a driving wheel and a speed measuring wheel to vertically support the wafer and drive it to rotate. Figure 1 As shown, the cleaning brushes arranged on both sides of the wafer roll around their axes to contact and clean the wafer surface and remove particles on the wafer surface.

[0006] Typically, washers are located inside the drive and tachometer wheels. Friction between the washers and the outer edge of the wafers forces the wafers to rotate in a certain direction. During the rotational cleaning process, the sides of the wafers may collide with the drive or tachometer wheels. This collision and friction creates wear debris that accumulates along with the cleaning fluid on the outer circumference of the washers. This wear debris can then reattach to the wafer surface, affecting the cleaning process.

[0007] Furthermore, the chemicals used in wafer cleaning produce residue, which can accumulate on the outer surface of the gasket due to gravity. Particles such as residue accumulated on the drive wheel or tachometer wheel can reattach to the wafer surface and affect wafer cleaning performance.

[0008] In addition, since the roller assembly is in contact with the edge area of the wafer, various particles formed during the cleaning process are likely to adhere to the wafer surface again, causing secondary contamination, such as the formation of "specialmap" defects in the edge area of the wafer, which directly affects the cleaning effect of the wafer. Summary of the Invention

[0009] An embodiment of the present invention provides a wafer cleaning method, which aims to solve at least one of the technical problems existing in the prior art.

[0010] An embodiment of the present invention provides a wafer cleaning method, comprising:

[0011] S1, placing the wafer on the roller assembly in the tank, the roller assembly vertically supports the wafer to be cleaned;

[0012] S2, the cleaning brush in the tank is passed water and moves toward the wafer to the cleaning position, and the cleaning brush rolls to clean the wafer surface in a contact manner;

[0013] S3, the cleaning brush that has completed scrubbing is away from the wafer, and the cleaning member in the tank body sprays fluid toward the roller assembly to flush away particles accumulated on the roller assembly.

[0014] In step S3, the spraying direction of the cleaning member is consistent with the rotation direction of the roller assembly.

[0015] In step S3, the cleaning member sprays fluid toward the center of the roller assembly and / or the area below the center of the roller assembly, and the sprayed fluid at least partially covers the outer peripheral surface corresponding to the contact point between the roller assembly and the outer edge of the wafer.

[0016] In step S3, the spraying direction of the cleaning member is away from the area where the wafer to be cleaned is located.

[0017] In step S3, the cleaning member is a spray pipe and / or a nozzle, and the distance between the spray port and the landing point of the sprayed fluid is 5 to 40 mm.

[0018] In step S3, the spray flow rate of the cleaning member is 200-2000 mL / min, and the spray flow rate of the cleaning member disposed toward the lower side is greater than the spray flow rate of the cleaning member disposed toward the upper side.

[0019] In some embodiments, the fluid sprayed by the cleaning member includes cleaning liquid, deionized water, and inert gas, which are mixed evenly and then sprayed toward the roller assembly.

[0020] In some embodiments, the temperature of the fluid sprayed by the cleaning member is 30-50°C.

[0021] In some embodiments, step S3 further includes: flushing components in the tank body spraying fluid toward the edge region of the wafer in an interlaced manner to remove particles in the edge region of the wafer from the inside to the outside.

[0022] In step S3, while the cleaning member cleans the roller assembly, the rinsing member sprays fluid toward the edge area of the wafer.

[0023] In step S3, the cleaning of the roller assembly by the cleaning member and the rinsing of the wafer edge area by the rinsing member are performed alternately.

[0024] In some embodiments, step S3 includes:

[0025] S31, the cleaning member cleans the roller assembly;

[0026] S32, detecting the number of particles on the wafer surface;

[0027] S33, if the number of particles on the wafer surface is within the allowable range, continue to clean the roller assembly according to step S31; if the number of particles on the wafer surface exceeds the set value, after brushing the next wafer, add a step of cleaning the edge area of the wafer with a rinser.

[0028] In step S3, during the cleaning process of the roller assembly, the cleaning member can swing around a fixed point so that the sprayed fluid partially covers the outer peripheral surface corresponding to the contact point between the roller assembly and the outer edge of the wafer.

[0029] In some embodiments, the cleaning member swings from the center of the roller assembly to an area below the center of the roller assembly.

[0030] In some embodiments, as the cleaning member swings toward the area below the center of the roller assembly, the spray flow rate of the cleaning member gradually increases.

[0031] The beneficial effects of the present invention include:

[0032] a. After the cleaning brush cleans the wafer, the cleaning element and / or the rinsing element are selectively activated to promptly remove particles accumulated on the roller assembly and focus on cleaning the wafer edge area to ensure the wafer cleaning effect;

[0033] b. The spray angle of the cleaning element is consistent with the rotation direction of the roller assembly to prevent the sprayed fluid from colliding against the roller assembly and affecting the flow field inside the tank;

[0034] c. The flushing parts are arranged in an interlaced manner and spray fluid toward the edge of the wafer to remove particles adhering to the wafer surface from the inside out, avoiding or reducing defects such as "special maps";

[0035] d. The cleaning member sprays fluid toward the roller assembly in a dynamic swinging manner to fully clean the particles attached to the roller assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The advantages of the present invention will become clearer and easier to understand through the detailed description made in conjunction with the following drawings, which are only exemplary and do not limit the scope of protection of the present invention, wherein:

[0037] Figure 1 It is a schematic diagram of a wafer cleaning device in the prior art;

[0038] Figure 2 is a schematic diagram of wear and tear / residue accumulated in the groove of the first drive wheel in the prior art;

[0039] Figure 3 This is a flow chart of a wafer cleaning method provided by one embodiment of the present invention;

[0040] Figure 4 is a schematic diagram of a wafer cleaning device provided by one embodiment of the present invention;

[0041] Figure 5 is a schematic diagram of a wafer cleaning device provided by yet another embodiment of the present invention;

[0042] Figure 6 is a schematic diagram of a wafer cleaning device provided by another embodiment of the present invention;

[0043] Figure 7 is a schematic diagram of a cleaning member provided by an embodiment of the present invention spraying through the center of a first driving wheel;

[0044] Figure 8 Schematic diagram of a cleaning member provided by one embodiment of the present invention spraying through an area below the center of a first driving wheel;

[0045] Figure 9 This is a flowchart corresponding to step S3 of a wafer cleaning method provided by one embodiment of the present invention;

[0046] Figure 10 is a schematic diagram of a cleaning member provided by an embodiment of the present invention swinging around a fixed point;

[0047] Figure 11 1 is a graph showing changes in the spray flow rate during the swinging process of the cleaning element provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0048] The technical solutions of the present invention are described in detail below in conjunction with specific embodiments and the accompanying drawings. The embodiments described herein are specific embodiments of the present invention and are used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary and should not be understood as limiting the embodiments of the present invention and the scope of protection of the present invention. In addition to the embodiments described herein, those skilled in the art can also adopt other obvious technical solutions based on the contents disclosed in the claims of this application and its specification, including technical solutions that adopt any obvious replacements and modifications to the embodiments described herein.

[0049] The drawings in this specification are schematic diagrams that assist in illustrating the concepts of the present invention and schematically illustrate the shapes of the various components and their interrelationships. It should be understood that in order to clearly illustrate the structures of the various components of the embodiments of the present invention, the drawings are not drawn to the same scale, and the same reference numerals are used to represent the same parts in the drawings.

[0050] In the present invention, "Chemical Mechanical Polishing (CMP)" is also called "Chemical Mechanical Planarization (CMP)", and the wafer (Wafer, W) is also called substrate (Substrate), and their meanings and actual functions are equivalent.

[0051] Figure 1 1 is a schematic structural diagram of a wafer cleaning device 1, which includes:

[0052] The tank body 10 has a roller assembly 20 disposed therein for vertically supporting and positioning the wafer W to be cleaned;

[0053] A cleaning brush 30 is disposed parallel to the tank body 10; the number of the cleaning brushes 30 is a pair, so as to clean the front and back sides of the wafer respectively; a drive motor (not shown) is connected to the end of the cleaning brush 30, and the drive motor drives the cleaning brush 30 to rotate around its axis;

[0054] The spray pipeline is provided at the upper portion of the tank body 10 , such as a moisturizing spray rod, a chemical spray rod, etc., to spray DIW and / or cleaning liquid onto the wafer W to ensure the cleaning effect of the cleaning brush 30 .

[0055] Figure 1In the figure, the roller assembly 20 includes a first driving wheel 21, a second driving wheel 22 and a speed measuring wheel 23. The first driving wheel 21 and the second driving wheel 22 are active wheels, which are respectively equipped with a driving motor to drive them to rotate; the test wheel 23 is a driven wheel, which is arranged in the middle position between the first driving wheel 21 and the second driving wheel 22 to detect the rotation speed during the wafer cleaning process, monitor whether the wafer rotates stably, and determine the cleaning status of the wafer.

[0056] During wafer cleaning, the first drive wheel 21 and the second drive wheel 22 rotate under the drive motor (not shown). Under the action of friction, the wafer W vertically arranged in the groove of the first drive wheel 21 and the second drive wheel 22 rotates around the axis of the wafer. The cleaning brush 30 contacts the surface of the wafer W and rotates around the axis of the cleaning brush 30. The cleaning brush 30 can be made of a porous material, such as polyvinyl alcohol, and can absorb a large amount of cleaning liquid used to brush the surface of the wafer W. The rolling cleaning brush 30 contacts the rotating wafer W to remove contaminants on the surface of the wafer W.

[0057] Figure 2 Shown Figure 1 A cross-sectional view of the first drive wheel 21 in the embodiment. The first drive wheel 21 typically includes a front cover and a rear cover, with a gasket 20a positioned between the front and rear covers. The front and rear covers interlock to form a recess 21a that defines the wafer. The gasket 20a is positioned within the recess 21a. Made of a relatively flexible plastic, the gasket 20a directly contacts the outer edge of the wafer, creating friction between the two to generate a rotational driving force.

[0058] In the prior art, the friction between the wafer and the outer wall of the roller assembly 20 will form wear materials, which will be accumulated on the outer peripheral surface of the gasket 20a along with the cleaning fluid. Figure 2 Furthermore, the chemicals used in wafer cleaning also form residues, which can accumulate on the outer surface of gasket 20a. These abrasive materials and / or residues can reattach to the wafer surface, causing secondary contamination, particularly at the wafer edge, where "special map" defects are most likely to occur.

[0059] Based on the above technical problems, the present invention provides a wafer cleaning method, the flow chart of which is as follows: Figure 3 A wafer cleaning method includes:

[0060] S1, placing the wafer W on the roller assembly 20 in the tank 10, the roller assembly 20 vertically supports the wafer W to be cleaned;

[0061] S2, the cleaning brush 30 in the tank 10 is passed water and moves toward the wafer W to a cleaning position, where the cleaning brush 30 rolls to clean the wafer surface in a contact manner;

[0062] S3 , the cleaning brush 30 that has completed scrubbing moves away from the wafer, and the cleaning member 40 in the tank body 10 sprays fluid toward the roller assembly 20 to flush away particles accumulated on the roller assembly 20 .

[0063] The following combination Figure 4 The wafer cleaning apparatus 2 is shown, and the steps of the above-mentioned wafer cleaning method are briefly described. Figure 4 and Figure 1 The main difference between the wafer cleaning apparatus shown is that the roller assembly 20 is equipped with a corresponding cleaning member 40 .

[0064] The cleaning member 40 is located inside the trough body 10 and is used to spray fluid toward the roller assembly 20 to remove particles such as wear and / or residues accumulated on the roller assembly 20, thereby preventing particles from accumulating at the contact position between the roller assembly 20 and the outer edge of the wafer and causing secondary contamination.

[0065] Figure 3 In step S1 shown, the wafer handling robot places the wafer from the entrance at the top of the tank body 10 onto the roller assembly 20, which includes Figure 3 The first driving wheel 21, the second driving wheel 22 and the speed measuring wheel 23 arranged therebetween are shown. At this time, a certain gap is reserved between the cleaning brush 30 and the wafer W to be cleaned to facilitate the wafer handling robot to efficiently and accurately place the wafer.

[0066] Before wafer cleaning, the surface of the wafer W needs to be properly moisturized, which can be achieved by opening the moisturizing spray rod in the tank body 10. The moisturizing spray rod sprays a certain flow of deionized water (DIW) to achieve wafer moisturization.

[0067] Next is step S2. Specifically, water is passed into the interior of the cleaning brush 30 to soften the outer periphery of the cleaning brush 30 due to water absorption, so that the cleaning brush 30 can fully contact the surface of the wafer. The cleaning brush 30 needs to be moved to the cleaning position toward the location of the wafer W. At the same time, the first drive wheel 21 and the second drive wheel 22 rotate in a certain direction driven by the drive motor. Under the action of the friction between the roller assembly 20 and the outer edge of the wafer, the wafer W rotates around its axis, so that the cleaning brush 30 can brush all areas of the wafer W.

[0068] Next, the chemical spray rod in the tank body 10 sprays a cleaning solution composed of chemicals toward the surface of the wafer W. The cleaning solution reacts with particles on the wafer surface. The cleaning brush 30 presses against the wafer surface and removes particles on the wafer surface by contact.

[0069] Finally, step S3 is performed. Specifically, after the cleaning brush 30 finishes cleaning the wafer, the cleaning brush 30 needs to be moved outward appropriately to prepare for cleaning the next wafer. Figure 3 The cleaning member 40 is shown spraying fluid toward the roller assembly 20 to flush the roller assembly 20 of accumulated particulate matter.

[0070] Furthermore, the first drive wheel 21, the second drive wheel 22, and the speed measuring wheel 23 are each equipped with a corresponding cleaning member 40. Each of the first drive wheel 21, the second drive wheel 22, and the speed measuring wheel 23 is internally provided with a gasket 20a made of a flexible material. The cleaning member 40 in the tank body 10 simultaneously sprays a fluid, such as DIW and / or a cleaning solution, toward the outer circumference of the gasket 20a through the groove of the roller assembly 20 to remove particulate matter accumulated on the outer circumference of the gasket 20a.

[0071] In the present invention, in order to prevent the fluid sprayed by the cleaning member 40 from hard collision with rotating components in the tank body 10 such as the wafer W and the roller assembly 20, thereby destroying the stability of the flow field in the tank body 10 and interfering with the wafer scrubbing effect. Figure 4 The spray direction of the cleaning element 40 shown matches the rotation direction of the wafer W to be cleaned. In other words, the spray direction of the cleaning element 40 in the tank body 10 needs to be adapted to the rotation direction of the wafer W. The spray direction of the cleaning element 40 configured for a clockwise rotating wafer W is different from that configured for a counterclockwise rotating wafer W. This is to avoid or control the negative impact of the spray fluid of the additional cleaning element 40 on wafer cleaning, reduce wafer scrubbing defects, especially reduce the "special map" defects in the wafer edge area, and ensure good cleaning results.

[0072] Figure 4 In the embodiment of the present invention, the spraying direction of the cleaning member 40 needs to match the rotation direction of the roller assembly 20. Specifically, the spraying direction of the cleaning member 40 needs to be consistent with the rotation direction of the roller assembly 20. That is, the spraying direction of the cleaning member 40 configured on the first drive wheel 21 is consistent with the rotation direction of the first drive wheel 21. This prevents the spraying direction of the cleaning member 40 from being opposite to the rotation direction of the first drive wheel 21, causing the fluid sprayed by the cleaning member 40 to directly collide with the outer peripheral surface of the first drive wheel 21, thereby causing the sprayed fluid to splash onto the wafer surface. Figure 4 The spraying directions corresponding to the cleaning members 40 configured for the second driving wheel 22 and the speed measuring wheel 23 are arranged in a similar manner.

[0073] Because the sprayed fluid can remove particles adhering to the outer circumference of the first drive wheel 21, these particles may re-splatter and adhere back to the wafer surface. To address this issue, the spray direction of the cleaning element 40 should be away from the area where the wafer to be cleaned is located. Specifically, the straight line formed by the cleaning element 40 along the spray direction should not intersect the area where the wafer to be cleaned W is located, to prevent particles removed from the roller assembly 20 from re-adhering to the wafer surface. Figure 4 In the illustrated embodiment, the straight lines corresponding to the spraying directions of the cleaning members 40 are all located outside the wafer W to be cleaned, so as to reduce or control the influence of the newly added cleaning members 40 on the wafer scrubbing effect.

[0074] In the present invention, the corresponding spray angle of the cleaning member 40 configured for the first drive wheel 21 is -60 to 60°, the corresponding spray angle of the cleaning member 40 configured for the second drive wheel 22 is -30 to 80°, and the corresponding spray angle of the cleaning member 40 configured for the speed measuring wheel 23 is -30 to 30°. Each cleaning member 40 simultaneously sprays fluid toward the outer peripheral surface of the gasket 20a of the roller assembly 20 to clean the particulate matter accumulated on the gasket 20a. It should be noted that the spray angle is the angle between the axis of the cleaning member 40 and the horizontal line connecting the centers of the first drive wheel 21 and the second drive wheel 22. The positive or negative value of the spray angle is related to the spray direction of the cleaning member 40. If the cleaning member 40 sprays fluid from top to bottom, the spray angle is positive; if the cleaning member 40 sprays fluid from bottom to top, the spray angle is negative.

[0075] Figure 4 In the embodiment shown, the spray angle θ1 of the cleaning member 40 corresponding to the first driving wheel 21 is 40°, the spray angle θ2 of the cleaning member 40 corresponding to the second driving wheel 22 is -45°, and the spray angle θ3 of the cleaning member 40 configured with the speed measuring wheel 23 located in the middle position is 30°.

[0076] To ensure that the cleaning element 40 effectively cleans the gasket 20a on the roller assembly 20, the fluid sprayed by the cleaning element 40 includes a cleaning liquid, deionized water, and an inert gas. These three components are uniformly mixed and then sprayed toward at least a portion of the outer circumference of the gasket 20a. In some embodiments, the inert gas is N2. The mixture of N2, cleaning liquid, and deionized water reduces the pressure in a localized area of the sprayed fluid, which in turn causes cavitation / erosion at the gas-liquid interface and the outer circumference of the gasket 20a, thereby enhancing the cleaning element 40's ability to remove particulate matter.

[0077] As one embodiment of the present invention, the temperature of the fluid sprayed by the cleaning member 40 is 30-50° C. The sprayed fluid at a certain temperature can reduce the adhesion between the particles and the outer peripheral surface of the gasket 20 a, which facilitates the rapid and efficient removal of the particles from the outer peripheral surface of the gasket 20 a, ensuring that the cleaning member 40 has good cleaning performance.

[0078] In addition, when the cleaning member 40 is positioned, although the problem that the cleaning member 40 cannot directly spray the contact area between the roller assembly 20 and the outer edge of the wafer is taken into consideration, the fluid sprayed by the cleaning member 40 may directly peel off and blow away the particles and splash them onto the wafer surface again, which will have a negative impact on the cleaning effect of the wafer edge area.

[0079] In order to solve the above problems, the present invention provides a further solution. Figure 5 It is a schematic diagram of a wafer cleaning device 3 provided in one embodiment of the present invention. In this embodiment, a cleaning brush 30 not shown is provided inside the trough body 10. The wafer cleaning device 3 also includes a flushing member 50. The flushing member 50 can spray fluid toward the edge area of the wafer to flush the edge area of the wafer and improve the cleaning effect of the edge area of the wafer.

[0080] Furthermore, the flushing parts 50 are arranged on both sides of the wafer, and the flushing parts 50 are staggered with each other to spray fluid toward the edge area of the wafer, thereby enhancing the cleaning of the edge area of the wafer and reducing the impact of wear and / or residues on the roller assembly 20 on the wafer cleaning effect.

[0081] It is understandable that the flushing member 50 also needs to avoid interference with the cleaning brushes 30 disposed on both sides of the wafer; specifically, the vertical position of the flushing member 50 should be slightly lower than Figure 1 The position of the washing brush 30 is shown.

[0082] Figure 6 FIG3 is a schematic diagram of another embodiment of a wafer cleaning apparatus 3 provided by the present invention. In this embodiment, the wafer cleaning apparatus 3 is equipped with both a cleaning element 40 and a rinsing element 50, allowing for flexible activation of the cleaning element 40 and / or the rinsing element 50. Specifically, the cleaning element 40 can promptly remove particles accumulated on the roller assembly 20, thereby preventing or reducing the impact of particles on the wafer cleaning effect. The rinsing element 50 further cleans particles splashed back to the wafer edge area, thereby controlling defects in the wafer edge area and ensuring the wafer cleaning effect.

[0083] Furthermore, after the cleaning brush 30 completes the wafer scrubbing process, the cleaning element 40 and rinsing element 50 disposed within the tank 10 can be simultaneously activated. Specifically, the cleaning element 40 rinses the outer circumference of the gasket 20a corresponding to the roller assembly 20, thereby promptly cleaning any particles adhering to the outer circumference of the gasket 20a. The staggered rinsing elements 50 spray fluid to remove particles that have re-adhered or re-attached to the wafer edge area from the inside out, effectively controlling the number of particles on the wafer surface after cleaning and avoiding "specialmap" defects at the wafer edge area.

[0084] Figure 7The figure is a schematic diagram of a first drive wheel 21 and its associated cleaning member 40, provided in one embodiment of the present invention. In this embodiment, the cleaning member 40 sprays fluid toward the center of the first drive wheel 21; specifically, the cleaning member 40 sprays fluid toward the center of the gasket 20a. This orientation of the cleaning member 40 avoids spraying fluid directly toward the point of contact between the first drive wheel 21 and the outer edge of the wafer, controls the direction and area of splashing of particles removed from the first drive wheel 21, avoids disrupting the flow field within the tank 10, and ensures a thorough cleaning of the wafer.

[0085] Figure 8 yes Figure 7 In a variation of the corresponding embodiment, in this embodiment, the cleaning member 40 sprays fluid toward the area below the center of the first drive wheel 21. That is, the fluid sprayed by the cleaning member 40 is further away from the contact point between the first drive wheel 21 and the outer edge of the wafer, thereby preventing abrasion and / or residue accumulated on the first drive wheel 21 from splashing onto the wafer surface and causing secondary contamination.

[0086] It should be noted that the fluid sprayed by the cleaning member 40 needs to at least partially cover the outer peripheral surface of the gasket 20a of the roller assembly 20 so as to promptly remove the particles accumulated on the outer peripheral surface of the gasket 20a, and prevent the particles on the gasket 20a from sticking back to the outer edge of the wafer or even spreading to the edge area of the wafer.

[0087] Figure 4 In the embodiment shown, the cleaning member 40 is a nozzle having an inner diameter of about Figure 2 The width of the groove 21a on the roller assembly 20 shown matches. Specifically, the inner diameter of the nozzle of the cleaning member 40 is smaller than the width of the groove 21a. It is understood that the cleaning member 40 can also be a nozzle that sprays a columnar water flow.

[0088] Figure 7 To ensure the spraying effect of the cleaning member 40, the distance L between the spray port of the cleaning member 40 and the point where the sprayed fluid lands is 5 to 40 mm. Preferably, the distance between the spray port of the cleaning member 40 and the point where the sprayed fluid lands is 10 to 20 mm. It will be appreciated that in some embodiments, it is necessary to configure a position adjustment mechanism for the cleaning member 40 to flexibly adjust the position of the cleaning member 40 and adjust and control the cleaning ability of the cleaning member 40 against particulate matter on the roller assembly 20.

[0089] The placement of the cleaning element 40 is related to the rinsing effect of the roller assembly 20. If the distance between the cleaning element 40 and the corresponding landing point of the roller assembly 20 is too close, it will cause severe splashback, which will affect the cleaning effect of the wafer edge area. In addition, the placement of the cleaning element 40 is related to factors such as the spray direction and whether it is close to the inner wall of the tank body 10. Therefore, when determining the placement of the cleaning element 40, it is necessary to comprehensively balance the rinsing effect and factors such as fluid splashback.

[0090] Figure 4 In the embodiment shown, to ensure the effective flushing of abrasions or residues on the roller assembly 20 in the wafer cleaning apparatus, the spray flow rate of the cleaning member 40 is 200-2000 mL / min. Preferably, the spray flow rate of the cleaning member 40 is 500-1500 mL / min.

[0091] It should be noted that the spray flow rate of the cleaning member 40 is related to its setting direction and position. The spray flow rate of the cleaning member 40 set toward the bottom is greater than the spray flow rate of the cleaning member 40 set toward the top. Figure 4 In the embodiment, a drain port 10a is provided at the bottom of the tank body 10 to promptly discharge the fluid collected at the bottom of the tank body 10. The cleaning member 40 positioned downward can directly collect the fluid mixed with particulate matter at the bottom of the tank body 10. However, the fluid sprayed by the cleaning member 40 positioned upward may collide with the sidewall of the tank body 10 and splash back onto the wafer surface. Therefore, it is necessary to control the spray flow rate of the cleaning member 40 positioned upward.

[0092] Specifically, the first driving wheel 21 is relatively close to the drain port 10a at the bottom of the tank body 10, and the cleaning member 40 configured for the first driving wheel 21 is arranged toward the bottom. In this case, the flow rate of the cleaning member 40 of the first driving wheel 21 can be set to the midline of the injection flow rate and above, such as 1200 to 1800 mL / min. Correspondingly, the cleaning member 40 configured for the second driving wheel 22 is tilted upward and close to the inner wall of the tank body 10. In order to prevent the fluid sprayed onto the inner wall of the tank body 10 from splashing back onto the wafer surface, it is necessary to precisely control the spray angle of the cleaning member 40, and it is also necessary to pay attention to the radiation area of the fluid splashed back from the inner wall of the tank body 10. In this case, the flow rate of the cleaning member 40 of the second driving wheel 22 can be set to the midline of the injection flow rate and below, such as 600 to 1000 mL / min.

[0093] As an embodiment of the present invention, the rinser 50 needs to be started after the scrubbing process is completed and before the wafer robot grabs the wafer, so as to utilize the above-mentioned interval to concentrate on cleaning the edge area of the wafer and improve the cleaning efficiency of the wafer.

[0094] Compared to the startup time of the rinsing unit 50, the startup time of the cleaning unit 40 is relatively flexible. Specifically, since the first and second drive wheels 21 and 22 are directly driven by the drive motor, cleaning the first and second drive wheels 21 and 22 only requires the cleaning unit 40 to be oriented toward the freely rotating drive wheels. Since the tachometer wheel 23 is a driven wheel, it rotates with the friction of the wafer. Therefore, when cleaning the tachometer wheel 23, the wafer must be positioned above the roller assembly 20.

[0095] As another embodiment of the present invention, the cleaning element 40 and the rinsing element 50 may also operate alternately. Specifically, first, the cleaning element 40 cleans the roller assembly 20; then, the rinsing element 50 is activated to clean particles from the wafer edge area using the fluid sprayed by the rinsing element 50; then, the cleaning element 40 cleans the roller assembly 20 again; and finally, the rinsing element 50 is activated again.

[0096] As Figure 3 A variation of step S3 shown may implement the following cleaning steps: first, the roller assembly 20 is cleaned using the cleaning member 40; then, the rinsing member 50 is activated to clean particles in the wafer edge area using the fluid sprayed by the rinsing member 50; finally, the cleaning member 40 and the rinsing member 50 are activated simultaneously.

[0097] Since the roller assembly 20 is more likely to be adhered to abrasives and / or chemical residues, the running time of the cleaning component 40 can be set to be slightly longer, such as 3 to 5 seconds. Correspondingly, the running time of the flushing component 50 can be set to 1 to 2 seconds.

[0098] Figure 9 This is a flow chart of step S3 corresponding to a wafer cleaning method provided by the present invention, which specifically includes:

[0099] S31, the cleaning member 40 cleans the roller assembly 20;

[0100] Specifically, the cleaning member 40 inside the tank body 10 is activated to spray fluid toward the outer peripheral surface of the gasket 20a of the roller assembly 20 to remove particles accumulated thereon;

[0101] S32, detecting the number of particles on the wafer surface;

[0102] The wafer that has been cleaned is transferred to the measurement table to measure the number of particles on the wafer surface;

[0103] S33, if the number of particles on the wafer surface exceeds the set value, after brushing the next wafer, a step of cleaning the edge area of the wafer with the rinser 50 is added;

[0104] If the number of particles on the wafer surface is within the allowable range, the roller assembly 20 is cleaned in step S31 .

[0105] The above step S3 is set mainly to consider the cleaning efficiency of the wafer. If the expected cleaning effect can be achieved by only starting the cleaning unit 40 or the rinsing unit 50, the process steps of wafer cleaning can be reduced, thereby improving the cleaning efficiency of the wafer cleaning device.

[0106] It should be noted that in step S33 , the steps of adding the rinsing element 50 to process the wafer edge area include the following schemes: starting simultaneously with the cleaning element 40 , starting after the cleaning element 40 has been running for a certain period of time, or starting after the cleaning element 40 has finished running.

[0107] Preferably, the cleaning element 40 and the rinsing element 50 need to be started simultaneously. This is because during the initial operation of the cleaning element 40, a large amount of particles adhere to the roller assembly 20, and the rinsing element 50 needs to promptly remove particles that have sputtered to the edge of the wafer to prevent the particles from being free and uncontrolled on the surface of the rotating wafer.

[0108] In addition, in order to enhance the cleaning ability of the roller assembly 20, the present invention also provides a wafer cleaning method, wherein steps S1 to S2 are the same as those in the embodiment of the present invention. Figure 3 Shows that the steps are consistent.

[0109] In step S3, during the cleaning process of the roller assembly 20, the cleaning member 40 in the tank 10 can swing around a fixed point so that the sprayed fluid partially covers the outer peripheral surface corresponding to the contact point between the roller assembly 20 and the outer edge of the wafer. In other words, the fluid sprayed by the cleaning member 40 can cover as much area of the gasket 20a of the roller assembly 20 as possible to ensure a good cleaning effect.

[0110] Furthermore, the cleaning member 40 swings from the center of the roller assembly 20 to the area below the center of the roller assembly 20 (washer 20a), as shown in FIG. Figure 10 shown. Figure 10 In the figure, the spray direction of the cleaning member 40 indicated by the dotted line points to the area below the center of the gasket 20a. In this way, the fluid sprayed by the cleaning member 40 has kinetic energy brought by the swing, which is conducive to fully removing the particles accumulated on the roller assembly 20.

[0111] Figure 10 In the embodiment, the cleaning member 40 swings at an angle β of 2 to 10°. It is understood that the swing angle of the cleaning member 40 is related to the location of the cleaning member 40. Preferably, the distance between the corresponding injection port of the cleaning member 40 and the point where the injected fluid lands is 5 to 15 mm, and the swing angle of the cleaning member 40 is 5 to 8°.

[0112] In step S3, while the cleaning member 40 is swinging toward the area below the center of the roller assembly 20 (gasket 20a), the jet flow rate of the cleaning member 40 is gradually increased, such as from 600 mL / min to 1200 mL / min, so as to fully remove the particles attached to the outer peripheral surface of the gasket 20a. Figure 11 It should be noted that, during the swinging process of the cleaning member 40 , the jet flow rate of the cleaning member 40 is gradually reduced to the initial jet flow rate, so as to form a dynamic change of the jet fluid and enhance the cleaning ability of the cleaning member 40 .

[0113] It should be noted that the wafer cleaning method provided by the present invention can also be applied to horizontal wafer cleaning, by configuring a cleaning member 40 and / or a rinsing member 50 for the horizontal wafer cleaning apparatus. For example, the cleaning member 40 can be configured for the rotating member that drives the wafer to rotate horizontally to remove particles from the outer peripheral surface corresponding to the contact area between the outer edge of the wafer and the rotating member, thereby preventing secondary contamination by particles. For another example, the rinsing member 50 can be specifically configured for the edge area of the wafer to enhance cleaning of the wafer edge area and ensure the wafer cleaning effect.

[0114] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative uses of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0115] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A wafer cleaning method, characterized in that: include: S1, placing the wafer on the roller assembly in the tank, the roller assembly vertically supports the wafer to be cleaned; S2, the cleaning brush in the tank is passed water and moves toward the wafer to the cleaning position, and the cleaning brush rolls to clean the wafer surface in a contact manner; S3, the cleaning brush that has completed scrubbing is moved away from the wafer, and the cleaning member in the tank sprays fluid toward the roller assembly to flush away particles accumulated on the roller assembly; The spraying direction of the cleaning member matches the rotation direction of the roller assembly and is away from the area where the wafer to be cleaned is located; The cleaning member configured for the first driving wheel of the roller assembly has a spray angle of -60 to 60 degrees, the cleaning member configured for the second driving wheel of the roller assembly has a spray angle of -30 to 80 degrees, and the cleaning member configured for the tachometer wheel of the roller assembly has a spray angle of -30 to 30 degrees; each cleaning member simultaneously sprays fluid toward the outer peripheral surface of the gasket of the roller assembly to clean particulate matter accumulated on the gasket; The flushing parts in the tank body spray fluid toward the edge area of the wafer in an interlaced manner to remove particles in the edge area of the wafer from the inside to the outside.

2. The wafer cleaning method according to claim 1, wherein: In step S3, the cleaning member is a spray pipe and / or a nozzle, and the distance between the spray port and the landing point of the sprayed fluid is 10 to 20 mm.

3. The wafer cleaning method according to claim 1, wherein: In step S3, the spray flow rate of the cleaning member is 500-1500 mL / min, and the spray flow rate of the cleaning member disposed toward the lower side is greater than the spray flow rate of the cleaning member disposed toward the upper side.

4. The wafer cleaning method according to claim 1, wherein: The operating time of the cleaning part is greater than the operating time of the rinsing part.

5. The wafer cleaning method according to claim 1, wherein: The cleaning member configured for the first driving wheel is arranged toward the lower side, and its spray flow rate is 1200-1800 mL / min.

6. The wafer cleaning method according to claim 1, wherein: The cleaning member configured for the second driving wheel is arranged to face upwards at an angle, and its spray flow rate is 600-1000 mL / min.

7. The wafer cleaning method according to claim 1, wherein: After the cleaning component finishes cleaning the roller assembly, the flushing component is started to clean the edge area of the wafer.

8. The wafer cleaning method according to claim 1, wherein: Step S3 includes: S31, the cleaning member cleans the roller assembly; S32, detecting the number of particles on the wafer surface; S33, if the number of particles on the wafer surface is within the allowable range, continue to clean the roller assembly according to step S31; if the number of particles on the wafer surface exceeds the set value, after brushing the next wafer, add a step of cleaning the edge area of the wafer with a rinser.

9. The wafer cleaning method according to claim 1, wherein: In step S3, during the cleaning process of the roller assembly, the cleaning member swings around a fixed point so that the sprayed fluid partially covers the outer peripheral surface corresponding to the contact point between the roller assembly and the outer edge of the wafer.

10. The wafer cleaning method according to claim 9, wherein: The cleaning member swings from the center of the roller assembly to an area below the center of the roller assembly.

11. The wafer cleaning method according to claim 10, wherein: The swing angle of the cleaning element is 2 to 10 degrees.

12. The wafer cleaning method according to claim 10, wherein: The distance between the spray port corresponding to the cleaning member and the landing point of the sprayed fluid is 5 to 15 mm.

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