A wafer vertical cleaning device and method

Abstract

The present invention discloses a device and method for vertically cleaning wafers, wherein the method comprises: when a rolling cleaning brush performs rolling brushing on a rotating wafer, causing a first spray rod to supply cleaning liquid to an upper area of ​​the wafer surface located above the cleaning brush; causing a second spray rod to supply cleaning liquid to a lower area of ​​the wafer surface located below the cleaning brush, wherein the lower area is located in an upstream area of ​​the cleaning brush relative to a rotation direction of the wafer.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor wafer processing, and in particular to a vertical wafer cleaning device and method. Background Art

[0002] In the semiconductor industry, wafer surface cleanliness is a key factor affecting semiconductor device reliability. During wafer manufacturing processes, such as deposition, plasma etching, photolithography, and electroplating, contamination and / or particles can be introduced onto the wafer surface, reducing wafer surface cleanliness and resulting in low semiconductor device yield.

[0003] To achieve a contaminant-free wafer surface, contaminants on the wafer surface must be removed to prevent them from re-residing on the wafer surface before processing. Therefore, multiple surface cleanings are required during the wafer manufacturing process to remove contaminants such as metal ions, atoms, organic matter, and particles attached to the wafer surface.

[0004] Roller brush cleaning is a widely used wafer cleaning method. Its operating principle is to rotate the wafer while supplying a cleaning fluid, such as deionized water or chemical solution, onto the wafer through a supply nozzle. Simultaneously, a roller-shaped cleaning element, such as a roller sponge, slides against the wafer. The wafer surface is cleaned by the sliding contact between the cleaning element and the wafer in the presence of the cleaning fluid.

[0005] However, the prior art has the following problems: since the wafer and the cleaning element rotate simultaneously, the area with the best scrubbing effect on the surface of the wafer is the first area where the relative speed between the cleaning element and the wafer is the highest. The other side of the first area, which is bounded by the center of the wafer, is the second area where the relative speed between the cleaning element and the wafer is the lowest, and the scrubbing effect is poor. During the cleaning process, cleaning fluid is supplied to the first area and the second area at the same time. The new cleaning fluid newly supplied to the first area will be mostly transferred to the second area and contact with the cleaning element as the wafer rotates, and the used cleaning fluid containing cleaning scraps below the cleaning element will return to the first area again as the wafer rotates, diluting the new cleaning fluid in the first area. In a word, the first area with good scrubbing effect not only has a small amount of new cleaning fluid newly supplied, but also will be diluted by the used cleaning fluid containing cleaning scraps, which ultimately leads to a decline in cleaning effect, residual pollutants on the wafer surface, and a reduction in yield rate. Summary of the Invention

[0006] The embodiments of the present invention provide a wafer vertical cleaning device and method, which aim to solve at least one of the technical problems existing in the prior art.

[0007] A first aspect of an embodiment of the present invention provides a vertical wafer cleaning device, comprising:

[0008] A wafer rotation assembly, used to support the wafer and drive the wafer to rotate in a vertical plane;

[0009] Two cleaning brushes are respectively set on both sides of the wafer and roll to scrub the wafer surface;

[0010] A cleaning brush driving mechanism, used for supporting the cleaning brush and driving the cleaning brush to move and rotate;

[0011] a first spray bar for supplying cleaning liquid to an upper area of ​​the wafer surface above the cleaning brush;

[0012] The second spray bar is used to supply cleaning liquid to the lower area of ​​the wafer surface below the cleaning brush, wherein the lower area is located in the upstream area of ​​the cleaning brush relative to the rotation direction of the wafer.

[0013] In one embodiment, the two cleaning brushes roll in opposite directions and apply downward friction to the wafer at their contact positions with the wafer.

[0014] In one embodiment, when viewed from the liquid inlet end of the cleaning brush, the wafer rotates upward, the cleaning brush on the left side of the wafer rotates clockwise, and the cleaning brush on the right side of the wafer rotates counterclockwise.

[0015] In one embodiment, the cleaning liquid is supplied at an angle of 5° to 30° relative to the wafer surface.

[0016] In one embodiment, the rotation speed of the wafer is 20-200 rpm.

[0017] In one embodiment, the wafer rotation assembly includes a driving roller and a driven roller, and the driving roller and the driven roller are arranged below the wafer.

[0018] In one embodiment, the active roller and the driven roller are provided with a clamping groove arranged along the outer circumference of the roller body.

[0019] In one embodiment, a rotation speed sensor for detecting the rotation speed of the wafer is provided on the active roller.

[0020] In one embodiment, the cleaning brush drive mechanism comprises:

[0021] A cleaning brush support assembly, used to support two cleaning brushes located on both sides of the wafer to be cleaned;

[0022] The cleaning brush moving assembly is connected to the cleaning brush supporting assembly to drive the cleaning brush supporting assembly and the cleaning brush thereon to move as a whole.

[0023] In one embodiment, the vertical wafer cleaning device further includes a displacement sensor for measuring the distance between the two cleaning brushes.

[0024] A second aspect of an embodiment of the present invention provides a method for vertically cleaning a wafer, comprising:

[0025] When the rotating cleaning brush is rolling and scrubbing the rotating wafer, the first spray bar supplies the cleaning liquid to the upper area of ​​the wafer surface above the cleaning brush;

[0026] The second spray bar supplies the cleaning liquid to a lower area of ​​the wafer surface below the cleaning brush, wherein the lower area is located upstream of the cleaning brush relative to a rotation direction of the wafer.

[0027] In one embodiment, the vertical wafer cleaning method further includes: enabling the second spray bar to spray chemical liquid to prevent the cleaning brush from being contaminated by pollutants.

[0028] In one embodiment, the vertical wafer cleaning method further includes: controlling two cleaning brushes located on both sides of the wafer to roll in opposite directions, and applying downward friction to the wafer at positions where the two cleaning brushes contact the wafer.

[0029] In one embodiment, the vertical wafer cleaning method further includes: controlling the rotation direction of the wafer so that the wafer rotates upward when viewed from the liquid inlet end of the cleaning brush.

[0030] In one embodiment, the vertical wafer cleaning method further comprises: rotating the wafer and controlling the first spray rod to start spraying the cleaning liquid onto the surface of the wafer;

[0031] The cleaning brush clamps the wafer and starts to clean it for a first preset time.

[0032] Controlling the first spray bar to stop spraying and causing the second spray bar to start spraying cleaning liquid onto the wafer surface for a second preset time period;

[0033] Repeat the above steps of alternately cleaning the first spray bar and the second spray bar.

[0034] In one embodiment, the cleaning liquid is supplied at an angle of 5° to 30° relative to the wafer surface.

[0035] In one embodiment, the rotation speed of the wafer is 20-200 rpm.

[0036] In one embodiment, the vertical wafer cleaning method further includes: detecting the contamination level of the cleaning brush, and when the contamination level of the cleaning brush reaches a certain level, controlling the first spray rod and / or the second spray rod to rotate a certain angle to rinse the cleaning brush.

[0037] In one embodiment, the vertical wafer cleaning method further includes: adjusting the operating angle of the second spray bar according to the operating condition of the second spray bar so that the cleaning liquid spray covers the boundary line between the wafer and the cleaning brush.

[0038] In one embodiment, the vertical wafer cleaning method further includes: adjusting the angle of the second spray rod so that it sprays perpendicularly to the wafer or the inner wall of the cleaning device, so as to use the cleaning liquid reflected by the wafer or the inner wall of the cleaning device to clean the second spray rod.

[0039] The beneficial effects of the embodiments of the present invention include: by designing a second spray rod under the cleaning brush, fresh cleaning liquid is provided to the area with the highest relative speed between the cleaning brush and the wafer, thereby improving the pollutant removal effect under the dual effects of large liquid supply and strong brushing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 FIG2 shows a wafer processing device provided by an embodiment of the present invention;

[0041] Figure 2 A vertical wafer cleaning device provided by an embodiment of the present invention is shown;

[0042] Figure 3 Shown Figure 2 The working principle of the vertical wafer cleaning device;

[0043] Figure 4 Shown Figure 3 The working principle of the cleaning brush;

[0044] Figure 5 A vertical wafer cleaning method provided by an embodiment of the present invention is shown;

[0045] Figure 6 A vertical wafer cleaning method provided by another embodiment of the present invention is shown. DETAILED DESCRIPTION

[0046] The technical solutions of the present invention are described in detail below in conjunction with specific embodiments and their 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. It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other. 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. It should be understood that, unless otherwise specified, for ease of understanding, the following descriptions of the specific embodiments of the present invention are all based on the description of the relevant equipment, devices, components, etc. in their original static natural state without external control signals and driving forces.

[0047] In addition, it should be noted that the terms used in this application to indicate directions, such as front, back, up, down, left, right, top, bottom, front, back, horizontal, vertical, etc., are only for the convenience of description to help understand the relative position or direction, and are not intended to limit the orientation of any device or structure.

[0048] In order to illustrate the technical solution of the present invention, the following description will be made with reference to the accompanying drawings and in combination with embodiments.

[0049] In this application, chemical mechanical polishing is also referred to as chemical mechanical planarization, and wafer is also referred to as chip, silicon chip, base plate or substrate, etc., and their meanings and actual functions are equivalent.

[0050] like Figure 1 As shown, a wafer processing device 100 provided by an embodiment of the present invention includes: a cache module 110 , two processing modules 120 and a front-end module 150 .

[0051] The cache module 110 may be provided with multiple layers, and the multi-layer cache module 110 may cache multiple wafers at the same time.

[0052] The processing modules 120 are used to polish wafers. The two processing modules 120 can work independently. Each processing module 120 can include: a polishing unit 121, a first robot 122, a transfer unit 123, a second robot 124 and a plurality of cleaning units 125.

[0053] like Figure 1As shown, the wafer processing equipment 100 includes four polishing units 121, which can be chemical mechanical polishing units. When the wafer processing equipment 100 is working, the wafer can enter any one or more of the four polishing units 121 for polishing. After completing one or more steps of polishing, the wafer is sent back to the transfer unit 123. Figure 1 As shown, each polishing unit 121 may include a polishing plate 211 , a polishing head 212 and a loading and unloading platform 213 . The loading and unloading platforms 213 of the two polishing units 121 are both disposed adjacent to the second robot 124 .

[0054] like Figure 1 As shown, a transfer module 130 may be formed between the polishing units 121 of the two processing modules 120, and the transfer units 123 may be disposed within the transfer module 130. The transfer unit 123 may transfer wafers between a first robot 122 and a second robot 124. The first robot 122 moves between the buffer module 110 and the transfer unit 123, and between the transfer unit 123 and the cleaning unit 125. The second robot 124 is used to transfer wafers to and from the polishing unit 121.

[0055] like Figure 1 As shown, each cleaning unit 125 may include: multiple cleaning modules 251, drying modules 252, vertical buffer modules 253 and flip modules 254, and the cleaning modules 251, drying modules 252, vertical buffer modules 253 and flip modules 254 are arranged side by side. Among them, at least one of the multiple cleaning modules 251 can be implemented by the wafer vertical cleaning device 1, and wafer cleaning can also be achieved by immersion, rotation, megasonic and / or spraying methods. The drying module 252 can achieve wafer drying by rotation and / or pulling methods. It is understandable that the number of cleaning modules 251 can also be other numbers and is not limited to Figure 1 shown.

[0056] like Figure 1 As shown, each cleaning unit 125 may further include: a third robot 255 and a fourth robot 256 , the third robot 255 moves above the cleaning module 251 and the vertical cache module 253 , and the fourth robot 256 moves above the cleaning module 251 , the drying module 252 and the flipping module 254 .

[0057] like Figure 1 As shown, an arrangement space 140 is left between the cleaning units 125 of the two processing modules 120 , and the two first manipulators 122 and the cache module 110 are arranged in the arrangement space 140 .

[0058] Figure 2It is a structural schematic diagram of a vertical wafer cleaning device 1 provided by an embodiment of the present invention. The vertical wafer cleaning device 1 includes a box 10, a wafer rotation assembly 20, two cleaning brushes 40, a cleaning brush driving mechanism 30, a first spray rod 61 and a second spray rod 62.

[0059] like Figure 2 As shown, in one embodiment of the present invention, a wafer rotation assembly 20 is used to support and rotate a wafer w in a vertical plane. The wafer rotation assembly 20 is disposed above the base. The wafer w to be cleaned is supported by the wafer rotation assembly 20 and rotated about a horizontal axis. The rotation speed of the wafer w is 20 to 200 rpm, preferably 20 to 50 rpm.

[0060] The wafer rotation assembly 20 includes a fixed seat, a pair of active rollers and a driven roller. The active rollers and the driven rollers are equipped with a slot for supporting the wafer w, and the slot is arranged around the outer circumference of the rollers. The active rollers and the driven rollers are arranged on the fixed seat. The driven rollers are arranged in the middle of the fixed seat, and the active rollers are symmetrically arranged on both sides of the driven rollers. A pair of active rollers and the driven rollers are arranged along the outer edge contour of the wafer w. The wafer w placed on the wafer rotation assembly 20 is limited by the slot, and the outer edge of the wafer w is arranged tangent to the bottom surface of the slot. The active rollers are equipped with a drive motor, and the drive motor drives the active rollers to rotate. The friction between the outer edge of the wafer w and the rollers drives the wafer w to rotate around its axis.

[0061] In one embodiment, a rotation speed sensor for detecting the rotation speed of the wafer w is provided on the driven roller. The rotation speed sensor can be implemented by a Hall sensor or a photoelectric switch sensor.

[0062] like Figure 2 As shown, in one embodiment of the present invention, two cleaning brushes are respectively arranged on both sides of the wafer w and roll to brush the surface of the wafer w. The two cleaning brushes 40 are respectively a first cleaning brush 41 and a second cleaning brush 42, which are respectively arranged on both sides of the wafer w to be cleaned, and can roll around their own axes to contact the surface of the wafer w to be cleaned for brushing. The cleaning brush 40 is a cylindrical structure, which is made of a material with good water absorption, such as polyvinyl alcohol (PVA). The cleaning brush 40 becomes soft after being filled with liquid and can be used to brush the wafer w, so the cleaning brush 40 needs to be kept filled with liquid at all times during the cleaning process.

[0063] The cleaning brushes 40 on either side of the wafer w can be moved horizontally to move away from or toward the wafer w. When the cleaning brushes 40 are away from the wafer w, a certain gap is left between them, allowing the wafer handling robot to grip the wafer w and remove it after cleaning. When the cleaning brushes 40 are moved toward the wafer w, they contact the wafer w and clean the surface of the wafer w.

[0064] like Figure 2 As shown, in one embodiment of the present invention, the cleaning brush driving mechanism 30 is used to drive two cleaning brushes 40 to move toward each other and clamp the wafer w at a certain angle for rolling brush cleaning. The cleaning brush driving mechanism 30 includes a cleaning brush supporting assembly and a cleaning brush moving assembly.

[0065] The cleaning brush support assembly is used to support two cleaning brushes 40 located on both sides of the wafer w to be cleaned.

[0066] The brush movement assembly is connected to the brush support assembly to drive the overall movement of the brush support assembly and the cleaning brush 40 thereon. The brush movement assembly includes a guide rail, a lead screw, and a driver. The guide rail and lead screw are each connected to the brush support assembly, driving the lead screw to move the brush support assembly along the guide rail. The driver is located at the end of the lead screw. The driver drives the lead screw, thereby driving the overall movement of the brush support assembly and the cleaning brush 40, so that both ends of the cleaning brush 40 simultaneously contact or move away from the wafer w. Furthermore, lead screws are provided at each end of the cleaning brush 40, allowing the movement distance of each end of the cleaning brush 40 to be adjusted separately.

[0067] In one embodiment, a displacement sensor is provided on the cleaning brush support assembly for measuring the distance between the two cleaning brushes.

[0068] like Figure 2 As shown, in one embodiment of the present invention, the wafer vertical cleaning device 1 further includes a liquid inlet mechanism 50 connected to one end of the cleaning brush, as shown in FIG. Figure 3 As indicated by the bold arrow in the middle box, liquid is continuously supplied to the cleaning brush via the liquid inlet mechanism 50, keeping the cleaning brush moist. The cleaning brush is made of a porous material capable of absorbing a large amount of liquid. The liquid can be an acidic or alkaline solution, or deionized water.

[0069] like Figure 2 As shown, in one embodiment of the present invention, a first spray bar 61 and a second spray bar 62 are provided in the vertical wafer cleaning device 1 for supplying cleaning liquid to the surface of the wafer w. The supply angle of the cleaning liquid relative to the surface of the wafer w is 5° to 30°.

[0070] A first spray bar 61 is used to supply cleaning liquid to an upper area of ​​the surface of the wafer w located above the cleaning brush, wherein the upper area is located above the contact area between the cleaning brush and the wafer w;

[0071] The second spray rod 62 is used to supply cleaning liquid to the lower area of ​​the surface of the wafer w below the cleaning brush, wherein the lower area is located upstream of the cleaning brush relative to the rotation direction of the wafer w.

[0072] The following combination Figure 2 Briefly describe the wafer cleaning operation method.

[0073] First, a robot places the wafer w to be cleaned on the wafer rotation assembly 20. At this time, a certain distance is reserved between the cleaning brush 40 and the side of the wafer w to provide working space for the robot. Under the action of friction, the wafer rotation assembly 20 drives the wafer w to rotate around its axis.

[0074] Next, the first spray bar 61 and the second spray bar 62 spray a cleaning liquid, such as an acidic or alkaline cleaning liquid, toward the rotating wafer w;

[0075] Next, the cleaning brush 40 rolls around its axis and moves toward the position of the wafer w, so that the cleaning brush 40 contacts the surface of the wafer w; the cleaning brush 40 rolls and scrubs the surface of the wafer w to remove contaminants on the surface of the wafer w, thereby scrubbing the surface of the wafer w;

[0076] After the wafer w is cleaned, the cleaning brush 40 moves toward the outside of the wafer w, and the cleaning brush 40 is separated from the surface of the wafer w;

[0077] Next, the first spray bar 61 continues to spray the cleaning liquid toward the rotating wafer w. After a period of time, the robot transfers the cleaned wafer w to the next process.

[0078] Refer to the following Figure 3 , introduces the working principle of the embodiment of the present invention.

[0079] First, in order to prevent the wafer W from being lifted from the slots of the active roller and the driven roller below it, the cleaning brush needs to be set to a specific rotation direction. Figure 3 As shown, the two cleaning brushes roll in opposite directions, and the contact positions with the wafer w apply downward friction to the wafer w, thereby confining the wafer w between the cleaning brushes and the rollers.

[0080] In the embodiment of the present invention, Figure 2 As shown, one end of the cleaning brush is connected to the liquid inlet mechanism 50, and the other end of the cleaning brush is connected to the cleaning brush driving mechanism 30. The end of the cleaning brush connected to the liquid inlet mechanism 50 is used as the liquid inlet end. Figure 2 and Figure 3 Center right position.

[0081] like Figure 3 As shown, looking from the liquid inlet end of the cleaning brush, that is, from Figure 3 The liquid inlet end of the liquid inlet mechanism 50 is connected to the liquid inlet end. Figure 3 Look in the direction indicated by the dotted arrow marked 50, as shown in Figure 4As shown, the left side of the wafer is the front side w1, which is also the side where the device is located, and the right side of the wafer is the back side w2. The side end face of the wafer w is rotated upward, and the first cleaning brush 41 on the left side of the wafer w rotates clockwise. The rotation speed of the first cleaning brush 41 is set to V B The second cleaning brush 42 located on the right side of the wafer w rotates counterclockwise, and the rotation speed of the second cleaning brush 42 is set to V B The two cleaning brushes sandwich the wafer w and apply a downward force to the wafer w, which is supported by the active roller and the driven roller.

[0082] like Figure 3 As shown, wafer w rotates counterclockwise in the direction facing wafer w, and the rotation speed of wafer w is set to V W According to the relative rotation direction of the cleaning brush and the wafer w, two areas are formed with the center of the wafer w as the dividing line, as shown in Figure 3 As shown in the dotted box in FIG, in the direction facing the wafer w, there is a first region R1 located on the right side of the wafer w and a second region R2 located on the left side of the wafer w.

[0083] In the first region R1, the relative speed between the cleaning brush and the wafer w is: V R1 =V B +V W It can be seen that the relative speed in the first region R1 is large and the scrubbing effect is good.

[0084] In the second region R2, the relative speed between the cleaning brush and the wafer w is: V R2 =V B -V W It can be seen that the relative speed in the second region R2 is small and the scrubbing effect is poor.

[0085] In this embodiment of the present invention, the first spray bar 61 sprays fresh cleaning liquid into the first region R1. Due to the friction and adhesion between the cleaning liquid and the wafer w, a large amount of fresh cleaning liquid is transferred to the second region R2 as the wafer w rotates. The second spray bar 62 sprays fresh cleaning liquid upstream below the wafer w. Driven by the wafer w, the fresh cleaning liquid is also supplied to the first region R1, thereby increasing the concentration and flow rate of the fresh cleaning liquid in the first region R1 and improving the cleaning effect. Furthermore, the second spray bar 62 can flush the area below the wafer w, removing used cleaning liquid and preventing cleaning debris from re-adhering to the cleaning brush or wafer w, thereby improving the removal of contaminants.

[0086] The vertical wafer cleaning device 1 provided in the embodiment of the present invention provides a large amount of fresh cleaning liquid to the first area R1 with significant scrubbing effect by adding a second spray rod 62, thereby achieving significantly improved cleaning effect and increasing wafer yield under the dual effects of large liquid supply and significant scrubbing effect.

[0087] like Figure 5 As shown, based on the structure of the above-mentioned vertical wafer cleaning device 1, an embodiment of the present invention further provides a vertical wafer cleaning method, comprising:

[0088] Step S51 , when the rolling cleaning brush is rolling and scrubbing the rotating wafer, the first spray bar 61 supplies the cleaning liquid to the upper area of ​​the wafer surface above the cleaning brush;

[0089] In step S52 , the second spray bar 62 supplies cleaning liquid to the lower area of ​​the wafer surface below the cleaning brush, wherein the lower area is located upstream of the cleaning brush relative to the rotation direction of the wafer.

[0090] The cleaning liquid may be water, such as deionized water (DIW), but is not limited to DIW. It may also be carbonated water, electrolyzed ionized water, hydrogen-rich water, or ozone water. The cleaning liquid may also be a chemical liquid, which may be an acidic solution or an alkaline solution.

[0091] See also Figure 3 Due to the specific motion relationship between the wafer and the cleaning brush, there is a first region R1 where the linear velocity is additive and a second region R2 where the linear velocity is subtractive. In the first region R1, the relative velocity between the wafer and the cleaning brush is high, and the brushing capacity is high.

[0092] The first spray bar 61 sprays fresh cleaning liquid onto the upper area of ​​the wafer surface above the cleaning brush, that is, Figure 3 In the first region R1 of the wafer w, due to the friction and adhesion between the cleaning liquid and wafer w, a large amount of fresh cleaning liquid will be transferred to the second region R2 as wafer w rotates. The second spray rod 62 sprays fresh cleaning liquid toward the lower area of ​​the wafer surface below the first cleaning brush 41, that is, sprays fresh cleaning liquid toward the upstream side below wafer w. Driven by wafer w, a large amount of fresh cleaning liquid is supplied to the first region R1, thereby increasing the concentration and flow rate of fresh cleaning liquid in first region R1 and improving the cleaning effect. Furthermore, the second spray rod 62 can flush the lower area of ​​wafer w, flushing away used cleaning liquid and preventing cleaning debris from re-adhering to the cleaning brush or wafer w, thereby improving the removal of contaminants.

[0093] The cleaning method provided by the embodiment of the present invention provides a large amount of fresh cleaning liquid to the first area R1 with high scrubbing ability by adding a second spray rod 62, thereby achieving both a large amount of fresh cleaning liquid and a high scrubbing ability in the same area, thereby significantly improving the cleaning effect and increasing the wafer yield.

[0094] In one embodiment, the second spray bar 62 is controlled to spray a chemical liquid to prevent contaminants from being carried back onto the cleaning brush. The chemical liquid can be an acidic or alkaline solution. The second spray bar 62 sprays the chemical liquid to remove contaminants from the used waste liquid and simultaneously clean the cleaning brush, thereby reducing secondary contamination.

[0095] like Figure 3 and Figure 4 As shown, in one embodiment, the rotation direction of the cleaning brushes is set to make the two cleaning brushes located on both sides of the wafer roll in opposite directions, and the contact positions with the wafer apply downward friction to the wafer.

[0096] like Figure 4 As shown, in one embodiment, the rotation direction of the wafer is set as follows: the rotation direction of the wafer is controlled so that the wafer rotates upward when viewed from the liquid inlet end of the cleaning brush.

[0097] This embodiment controls the rotation direction of the wafer and the two cleaning brushes in accordance with this specific coordination method, thereby preventing the wafer from being lifted off the rollers supporting it by the rotating cleaning brushes.

[0098] like Figure 6 As shown, in another embodiment, the specific steps of the cleaning method include:

[0099] In step (1), the wafer is placed on a wafer rotating assembly. Specifically, a robot places the wafer on a roller located at the bottom of a cleaning chamber.

[0100] Step (2) rotates the wafer and controls the first spray rod 61 to start spraying cleaning liquid onto the wafer surface, which may be deionized water and chemical liquid.

[0101] Step (3): the cleaning brush clamps the wafer and starts to scrub it for a first preset time period, which may be 10s to 30s, preferably 20s.

[0102] Step (4) controls the first spray rod 61 to stop spraying, and enables the second spray rod 62 to start spraying cleaning liquid onto the wafer surface, which can be deionized water and chemical liquid, and continues for a second preset time, which can be 10s to 30s, preferably 20s.

[0103] Step (5) repeats the above alternating cleaning of the first spray bar 61 and the second spray bar 62, i.e. steps (2) to (4), for 2 to 5 times, the specific number of times being determined by the process.

[0104] Step (6): After cleaning, the robot takes the slice.

[0105] After testing and verification, this embodiment can effectively improve the cleaning effect.

[0106] Furthermore, in one embodiment, the degree of contamination of the cleaning brush is detected. When the degree of contamination of the cleaning brush reaches a certain level, the first spray bar and / or the second spray bar are controlled to rotate to a certain angle to rinse the cleaning brush. The degree of contamination of the cleaning brush can be detected by an image sensor installed in the housing 10. For example, the degree of contamination can be reflected by light and dark levels, brightness, etc.

[0107] In summary, the vertical wafer cleaning method provided by the embodiment of the present invention can achieve fresh cleaning liquid entering the first region R1 where the linear velocity is added by adding the second spray rod 62 at the lower part of the cleaning chamber, thereby enhancing the pollutant removal capability.

[0108] Preferably, the box body can be optionally equipped with an image sensor or an angle sensor, etc., to adjust its operating angle according to the operating conditions of the second spray rod 62 fed back by the sensor, and / or adjust its operating angle according to the measured positioning angle of the second spray rod 62; the effect of such adjustment is to make the cleaning liquid or deionized water sprayed therefrom more effective in decontamination, and to adapt to roller brushes of different materials and / or flexibility (roller brushes of different materials have different degrees of deformation when squeezed).

[0109] In particular, the second spray bar 62 can be adjusted so that its nozzle sprays cleaning liquid or other liquid perpendicularly to the wafer or the inner wall of the box, thereby utilizing the cleaning liquid reflected by the wafer to achieve reverse cleaning (self-cleaning) of the second spray bar 62.

[0110] 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.

[0111] 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.

Claims

1. A vertical wafer cleaning device, characterized in that: include: A wafer rotation assembly, used to support the wafer and drive the wafer to rotate in a vertical plane; Two cleaning brushes are respectively arranged on both sides of the wafer and roll to scrub the surface of the wafer, wherein the two cleaning brushes roll in opposite directions and apply downward friction to the wafer at the contact position with the wafer; A cleaning brush driving mechanism, used for supporting the cleaning brush and driving the cleaning brush to move and rotate; a first spray bar for supplying cleaning liquid to an upper area of ​​the wafer surface above the cleaning brush; The second spray rod is used to supply cleaning liquid to the lower area of ​​the wafer surface below the cleaning brush, wherein the lower area is located in the upstream area of ​​the cleaning brush relative to the rotation direction of the wafer. The second spray rod is used to spray chemical liquid to prevent the cleaning brush from being back-contaminated with contaminants.

2. The vertical wafer cleaning device according to claim 1, characterized in that: Looking from the liquid inlet end of the cleaning brush, the wafer rotates upward, the cleaning brush located on the left side of the wafer rotates clockwise, and the cleaning brush located on the right side of the wafer rotates counterclockwise.

3. The vertical wafer cleaning device according to claim 1, wherein: The supply angle of the cleaning liquid relative to the wafer surface is 5°~30°.

4. The vertical wafer cleaning device according to claim 1, wherein: The rotation speed of the wafer is 20-200 rpm.

5. The vertical wafer cleaning device according to claim 1, wherein: The wafer rotating assembly comprises a driving roller and a driven roller, and the driving roller and the driven roller are arranged below the wafer.

6. The vertical wafer cleaning device according to claim 5, characterized in that: The active roller and the driven roller are provided with clamping grooves arranged along the outer peripheral sides of the roller bodies.

7. The vertical wafer cleaning device according to claim 5, characterized in that: The active roller is provided with a rotation speed sensor for detecting the rotation speed of the wafer.

8. The vertical wafer cleaning device according to claim 1, wherein: The cleaning brush driving mechanism comprises: A cleaning brush support assembly, used to support two cleaning brushes located on both sides of the wafer to be cleaned; The cleaning brush moving assembly is connected to the cleaning brush supporting assembly to drive the cleaning brush supporting assembly and the cleaning brush thereon to move as a whole.

9. The vertical wafer cleaning device according to any one of claims 1 to 8, characterized in that: A displacement sensor is also included for measuring the distance between the two cleaning brushes.

10. A vertical wafer cleaning method, characterized in that: include: Controlling the two cleaning brushes located on both sides of the wafer to roll in opposite directions, and applying downward friction to the wafer at the contact position with the wafer; When the rotating cleaning brush is rolling and scrubbing the rotating wafer, the first spray bar supplies the cleaning liquid to the upper area of ​​the wafer surface above the cleaning brush; The second spray bar supplies the cleaning liquid to a lower area of ​​the wafer surface below the cleaning brush, wherein the lower area is located upstream of the cleaning brush relative to the rotation direction of the wafer; The second spray bar is used to spray chemical liquid to prevent the cleaning brush from being stained with pollutants.

11. The vertical wafer cleaning method according to claim 10, wherein: Also includes: The rotation direction of the wafer is controlled so that the wafer rotates upward when viewed from the liquid inlet end of the cleaning brush.

12. The vertical wafer cleaning method according to claim 10, wherein: Also includes: The wafer is rotated and the first spray rod is controlled to start spraying cleaning liquid onto the surface of the wafer; The cleaning brush clamps the wafer and starts to clean it for a first preset time. Controlling the first spray bar to stop spraying and causing the second spray bar to start spraying cleaning liquid onto the wafer surface for a second preset time period; Repeat the above steps of alternately cleaning the first spray bar and the second spray bar.

13. The vertical wafer cleaning method according to claim 10, wherein: The supply angle of the cleaning liquid relative to the wafer surface is 5° to 30°.

14. The vertical wafer cleaning method according to claim 10, wherein: The rotation speed of the wafer is 20-200 rpm.

15. The vertical wafer cleaning method according to claim 10, wherein: Also includes: The contamination degree of the cleaning brush is detected. When the contamination degree of the cleaning brush reaches a certain degree, the first spray rod and / or the second spray rod is controlled to rotate to a certain angle to rinse the cleaning brush.

16. The vertical wafer cleaning method according to claim 10, wherein: The operating angle of the second spray bar is adjusted according to the operating condition thereof so that the cleaning liquid spray covers the boundary line between the wafer and the cleaning brush.

17. The vertical wafer cleaning method according to claim 10, wherein: The angle of the second spray bar is adjusted so that it sprays perpendicularly to the wafer or the inner wall of the cleaning device, so as to use the cleaning liquid reflected by the wafer or the inner wall of the cleaning device to clean the second spray bar.

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