Cleaning device, cleaning method and wafer thinning equipment

Abstract

The embodiment of the invention provides a cleaning device, a cleaning method and wafer thinning equipment, relates to the technical field of wafer processing, and is used for reducing adhesion of crystal slag deposited at the bottom of a cleaning tank on a cleaning part so as to reduce the risk of scratching a wafer. The cleaning device comprises a cleaning tank, a liquid inlet valve and a liquid discharge valve. The cleaning tank comprises a bottom wall and a side wall arranged around the bottom wall. The side wall is provided with a liquid inlet, and the bottom wall is provided with a liquid outlet. The bottom wall is funnel-shaped, and the liquid outlet is located in the center of the bottom wall. In the first direction, the distance between the liquid inlet and the end face of the end, close to the bottom wall, of the side wall is larger than one half of the size of the side wall. The first direction is perpendicular to the plane where the end face of the side wall close to the bottom wall is located. And the liquid inlet valve is arranged at the liquid inlet. And the liquid discharge valve is arranged at the liquid discharge port. The cleaning device is used for cleaning and wiping the cleaning part of the wafer.

Description

Technical Field

[0001] The present disclosure relates to the field of wafer processing technology, and in particular to a cleaning device and a cleaning method, and a wafer thinning device. Background Art

[0002] Wafer refers to the silicon chip used in the production of silicon semiconductor integrated circuits. Because of its round shape, it is called a wafer. Various circuit component structures can be processed on the silicon wafer to become integrated circuit products with specific electrical functions. In the semiconductor industry process, it is usually necessary to remove a certain thickness of excess substrate material on the back of the wafer before the integrated circuit is packaged to be able to produce more complex and smaller integrated circuits. This process is called wafer back thinning process. In the wafer back thinning process, crystal slag is easy to adhere to the surface of the wafer.

[0003] In the related art, a cleaning component is generally used to wipe the wafer to remove the slag on the wafer. In the process of removing the slag, the slag will adhere to the side of the cleaning component. Therefore, the cleaned component after wiping needs to be moved to a cleaning device for cleaning to remove the slag on the cleaning component. The cleaning device includes a cleaning tank, and the cleaned component after wiping is immersed in the cleaning tank for cleaning, and the slag will fall off the cleaning component and sink to the bottom of the cleaning tank. Figure 1 As shown, the cleaning tank includes a liquid inlet, which is located at the bottom side of the cleaning tank. Cleaning liquid is added into the cleaning tank through the liquid inlet to maintain the cleaning tank full and overflowing state, so as to maintain the cleanliness of the cleaning liquid in the cleaning tank.

[0004] However, in the process of adding cleaning liquid into the cleaning tank, the crystal slag deposited at the bottom of the cleaning tank is not easy to be removed from the cleaning tank, and is easily affected by the cleaning liquid flow from the bottom side liquid inlet and adheres to the bottom of the cleaning component. When the cleaning component wipes the crystal slag on the wafer again, the crystal slag on the cleaning component may scratch the surface of the wafer. Summary of the invention

[0005] The purpose of the embodiments of the present disclosure is to provide a cleaning device and a cleaning method, and a wafer thinning device, which are used to reduce the risk of crystal slag adhering to the cleaning components and thereby scratching the wafer.

[0006] To achieve the above objectives, the embodiments of the present disclosure provide the following technical solutions:

[0007] On the one hand, a cleaning device is provided. The cleaning device includes a cleaning tank, a liquid inlet valve and a liquid discharge valve. The cleaning tank includes a bottom wall and a side wall arranged around the bottom wall. The side wall is provided with a liquid inlet, the bottom wall is provided with a liquid discharge port, the bottom wall is funnel-shaped, and the liquid discharge port is located at the center of the bottom wall. Along a first direction, the distance between the liquid inlet and an end face of the side wall close to the bottom wall is greater than half of the size of the side wall. The first direction is perpendicular to the plane where the end face of the side wall close to the bottom wall is located. The liquid inlet valve is arranged at the liquid inlet. The liquid discharge valve is arranged at the liquid discharge port.

[0008] In the above cleaning device, the side wall is provided with a liquid inlet, and along the first direction, the size between the liquid inlet and one end of the side wall close to the bottom wall is greater than or equal to one half of the size of the side wall. In this way, the distance between the liquid inlet and the bottom of the cleaning tank is relatively far, and the impact force of the cleaning liquid at the liquid inlet will not flush up the crystal slag deposited at the bottom of the cleaning tank, which can improve the problem of the impact force of the liquid inlet flushing up the crystal slag deposited at the bottom of the cleaning tank, and reduce the risk of the flushed crystal slag adhering to the bottom surface of the cleaning component and causing the crystal slag to scratch the surface of the wafer.

[0009] In some embodiments, the cleaning device further comprises a first liquid level sensor and a second liquid level sensor. The first liquid level sensor is disposed on the side wall. Along the first direction, the distance between the first liquid level sensor and an end surface of the side wall close to the bottom wall is greater than or equal to half of the size of the side wall. The second liquid level sensor is disposed above the drain port.

[0010] In some embodiments, the cleaning device further comprises a controller. The controller is electrically connected to the first liquid level sensor, the second liquid level sensor, the liquid inlet valve and the liquid discharge valve. The controller is configured to control the liquid inlet valve to open and control the liquid inlet valve to close according to a first sensing signal from the first liquid level sensor; and control the liquid discharge valve to open and control the liquid discharge valve to close according to a second sensing signal from the second liquid level sensor.

[0011] In some embodiments, the cleaning device further comprises an alarm device. The alarm device is electrically connected to the control. The controller is further configured to issue an alarm signal if the first sensing signal is not received within a first preset time after the inlet valve is opened and the drain valve is closed; and to issue an alarm signal if the second sensing signal is not received within a second preset time after the inlet valve is closed and the drain valve is opened.

[0012] In some embodiments, the cleaning device further comprises a plurality of nozzles. The plurality of nozzles are disposed on the side wall and are spaced apart along the circumference of the side wall. With respect to a plane where an end surface of one end of the side wall close to the bottom wall is located, the height of the plurality of nozzles is higher than the height of the liquid inlet.

[0013] In some embodiments, the included angle between the spraying direction of the nozzle and the side wall is 30° to 60°, and the spraying range of the multiple nozzles covers the entire circumference of the cleaning component.

[0014] In some embodiments, the plurality of spray heads are farther away from the bottom wall than the first liquid level sensor.

[0015] On the other hand, an embodiment of the present disclosure further provides a wafer thinning device. The wafer thinning device includes a grinding device and a cleaning device as described in any of the above embodiments. The grinding device is configured to grind the wafer to be thinned. The cleaning device is configured to wipe the ground wafer with a cleaning component, and after wiping, move the cleaning component to a cleaning tank for cleaning.

[0016] The above-mentioned wafer thinning equipment has the same structure and beneficial technical effects as the cleaning devices provided in some of the above-mentioned embodiments, which will not be repeated here.

[0017] On the other hand, the embodiments of the present disclosure also provide a cleaning method. The cleaning method comprises: after the cleaning component wipes the ground wafer, the cleaning component is moved into the cleaning tank; the drain valve is closed, and the inlet valve is opened to inject cleaning liquid into the cleaning tank; when the liquid level of the cleaning tank rises to a first height, the inlet valve is closed, and the cleaning component is immersed in the cleaning liquid; when the grinding device is in a working state, after immersion, the cleaning component is moved to the ground wafer to wipe the wafer; when the grinding device is in an idle state, the cleaning component is kept immersed in the cleaning liquid, and the cleaning liquid in the cleaning tank is replaced at a preset period.

[0018] In some embodiments, before immersing the cleaning component in the cleaning liquid, the cleaning method further includes: opening a plurality of nozzles to rinse the cleaning component; and after self-cleaning the cleaning tank, injecting the cleaning liquid into the cleaning tank. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present disclosure, the following briefly introduces the drawings required to be used in some embodiments of the present disclosure. Obviously, the drawings described below are only drawings of some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can also be obtained based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams, and are not limitations on the actual size of the product involved in the embodiments of the present disclosure, the actual process of the method, the actual timing of the signal, etc.

[0020] Figure 1 A structural diagram of a related technology of a cleaning device according to some embodiments;

[0021] Figure 2 is a structural diagram of a wafer thinning device according to some embodiments;

[0022] Figure 3 A structural diagram of a cleaning component wiping a wafer according to some embodiments;

[0023] Figure 4 According to some embodiments Figure 2 A partial enlarged view of middle A;

[0024] Figure 5 is a diagram showing the positions of multiple nozzles and cleaning components according to some embodiments;

[0025] Figure 6 and Figure 7 FIG. 4 is a diagram showing steps of a cleaning method according to some embodiments. DETAILED DESCRIPTION

[0026] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in some embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments provided by the present disclosure, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present disclosure.

[0027] Unless the context requires otherwise, throughout the specification and claims, the term "including" is to be interpreted as an open, inclusive meaning, that is, "including, but not limited to". In the description of the specification, the terms "one embodiment", "some embodiments", "exemplary embodiments", "examples" or "some examples" and the like are intended to indicate that specific features, structures, materials or characteristics associated with the embodiment or example are included in at least one embodiment or example of the present disclosure. The schematic representations of the above terms do not necessarily refer to the same embodiment or example. In addition, the specific features, structures, materials or characteristics described may be included in any one or more embodiments or examples in any appropriate manner.

[0028] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present disclosure, unless otherwise specified, "plurality" means two or more.

[0029] When describing some embodiments, the expression "connection" and its derivatives may be used. The term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. The embodiments disclosed herein are not necessarily limited to the contents of this document.

[0030] The use of "adapted to" or "configured to" herein is meant to be open and inclusive language that does not exclude devices adapted or configured to perform additional tasks or steps.

[0031] As used herein, "parallel", "perpendicular", and "equal" include the situations described and situations similar to the situations described, and the range of the similar situations is within the acceptable deviation range, wherein the acceptable deviation range is determined by a person of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of a particular quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, wherein the acceptable deviation range of approximate parallelism may be, for example, a deviation within 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein the acceptable deviation range of approximate perpendicularity may also be, for example, a deviation within 5°. "Equal" includes absolute equality and approximate equality, wherein the acceptable deviation range of approximate equality may be, for example, the difference between the two equalities is less than or equal to 5% of either one.

[0032] Exemplary embodiments are described herein with reference to cross-sectional views and / or plan views that are idealized exemplary drawings. In the drawings, the thickness of the layers and the area of ​​the regions are exaggerated for clarity. Therefore, variations in the shapes relative to the drawings due to, for example, manufacturing techniques and / or tolerances are conceivable. Therefore, the exemplary embodiments should not be interpreted as being limited to the shapes of the regions shown herein, but include shape deviations due to, for example, manufacturing. For example, an etched region shown as a rectangle will typically have curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to illustrate the actual shapes of the regions of the device, and are not intended to limit the scope of the exemplary embodiments.

[0033] The embodiment of the present disclosure provides a wafer thinning device 1000. Figure 1 As shown, the wafer thinning equipment 1000 includes a cleaning device 100 and a grinding device.

[0034] The grinding device is configured to grind the wafer 1 to be thinned so as to remove a certain thickness of excess base material on the back of the wafer 1. During the grinding process, slag will remain on the surface of the wafer 1. Therefore, the ground wafer 1 will be transferred to the cleaning device 100 to remove the slag on the ground wafer 1.

[0035] Exemplarily, the grinding device includes a first wafer carrier and a grinding wheel.

[0036] The first wafer stage is configured to fix the wafer 1 and drive the wafer 1 to rotate. For example, the wafer 1 can be fixed on the first wafer stage by vacuum adsorption and rotate with the first wafer stage.

[0037] The grinding wheel is used to grind the wafer 1 so as to remove a certain thickness of excess matrix material on the back side of the wafer 1. During the grinding process, crystal slag will remain on the surface of the wafer 1.

[0038] The cleaning device 100 is configured to wipe the ground wafer 1 with the cleaning component 2 to remove the crystal slag on the back side of the ground wafer 1. In the process of wiping the wafer 1, the crystal slag will adhere to the cleaning component 2. For example, the shape of the cleaning component 2 is circular. For example, the cleaning component 2 can be a sponge.

[0039] For example, Figure 2 As shown, the cleaning device 100 includes a robot arm 10, a cleaning tank 20 and a fixing table 90. The robot arm 10 is configured to fix the cleaning component 2 and move the cleaning component 2 into or out of the cleaning tank 20.

[0040] The fixing table 90 is configured to fix the ground wafer 1 and drive the ground wafer 1 to rotate.

[0041] Exemplarily, the fixing table 90 includes a second wafer stage 91 and a plurality of fixing blocks 92 . The plurality of fixing blocks 92 are arranged at intervals along the circumference of the second wafer stage 91 , and the plurality of fixing blocks 92 are configured to limit movement of the ground wafer 1 .

[0042] For example, the fixing platform 90 includes three fixing blocks 92 , and the three fixing blocks 92 are evenly arranged along the circumference of the second wafer stage 91 .

[0043] In this way, the ground wafer 1 is transferred to the second wafer stage 91, and a plurality of fixed blocks 92 are arranged around the circumference of the ground wafer 1. The robot arm 10 can drive the cleaning component 2 to move above the ground wafer 1, that is, above the second wafer stage 91, and the second wafer stage 91 drives the ground wafer 1 to rotate. Figure 2 and Figure 3As shown, the robot arm 10 can drive the cleaning component 2 to move to the center of the ground wafer 1, and then make the cleaning component 2 contact with the surface of the ground wafer 1, and move along the radial direction of the ground wafer 1 to wipe the ground wafer 1 and remove the crystal slag on the wafer 1. In this process, the crystal slag is easily attached to the cleaning component 2. The robot arm 10 can also drive the cleaning component 2 to move to the cleaning tank 20. Under the action of a cleaning liquid such as ultrapure water, alcohol or isopropyl alcohol, the crystal slag falls from the cleaning component 2 into the cleaning tank 20, and is deposited at the bottom of the cleaning tank 20 ( Figure 1 and Figure 4 The black dots in the figure represent crystal slag. That is, the cleaning device 100 is further configured to move the cleaning component 2 after wiping the wafer 1 to the cleaning tank 20 for cleaning.

[0044] In related technologies, such as Figure 1 As shown, the liquid inlet of the cleaning tank in the cleaning device is close to the bottom of the cleaning tank. In the process of injecting cleaning liquid into the cleaning tank through the liquid inlet, the impact force of the cleaning liquid will flush up the crystal slag deposited at the bottom of the cleaning tank, thereby adhering to the bottom of the cleaning component. When the cleaning component wipes the wafer again, the crystal slag on the cleaning component is easy to scratch the surface of the wafer.

[0045] In order to solve the above problems, Figure 4 As shown, in the cleaning device 100 provided in some embodiments of the present disclosure, the cleaning tank 20 includes a bottom wall 21 and a side wall 22 arranged around the bottom wall 21 .

[0046] like Figure 4 As shown, the side wall 22 is provided with a liquid inlet 221, and along the first direction X, the distance H1 between the center of the liquid inlet 221 and the end surface of the side wall 22 close to the bottom wall 21 is greater than or equal to half of the size H2 of the side wall 22. The first direction X is perpendicular to the plane where the end surface of the side wall 22 close to the bottom wall 21 is located.

[0047] For example, the distance H1 between the liquid inlet 221 and the end surface of the side wall 22 close to the bottom wall 21 is greater than or equal to one half, two thirds, three quarters or four fifths of the size H2 of the side wall 22, which is not specifically limited in the embodiments of the present disclosure.

[0048] In this way, the distance between the liquid inlet 221 and the bottom of the cleaning tank 20 is greater, and the impact force from the liquid inlet 221 will not flush out the crystal slag deposited at the bottom of the cleaning tank 20, which can improve the problem of the impact force of the liquid inlet 221 flushing out the crystal slag deposited at the bottom of the cleaning tank 20, and reduce the risk of the flushed crystal slag adhering to the bottom surface of the cleaning component 2 and causing the crystal slag to scratch the surface of the wafer 1.

[0049] In addition, if Figure 4 As shown, the bottom wall 21 is provided with a drain port 211 .

[0050] In this case, the crystal slag deposited at the bottom of the cleaning tank 20 can be discharged from the cleaning tank through the drain port 211. When the cleaning liquid is injected into the cleaning tank 20, since there is no or a small amount of crystal slag at the bottom of the cleaning tank 20, the risk of the crystal slag deposited at the bottom of the cleaning tank 20 adhering to the cleaning component 2 can be reduced, thereby reducing the risk of scratching the wafer 1.

[0051] In some embodiments, Figure 4 As shown, the angle between the bottom wall 21 and the side wall 22 is greater than 90°. For example, the angle between the bottom wall 21 and the side wall 22 is 100°, 125° or 145°, which is not specifically limited in the embodiments of the present disclosure.

[0052] In this case, under the action of gravity, the slag on the bottom wall 21 can move to the drain port 211, and then be discharged from the cleaning tank 20 through the drain port 211. In other words, the angle between the bottom wall 21 and the side wall 22 is greater than 90°, which can reduce the risk of slag adhering to the bottom wall 21.

[0053] For example, Figure 2 and Figure 4 As shown, the bottom wall 21 is funnel-shaped to further reduce the risk of slag adhering to the bottom wall 21, so that the slag is concentrated and deposited at the lowest point of the bottom wall 21. The drain port 211 is located at the center of the bottom wall 21, so that the drain port 211 is located at the lowest point of the bottom wall 21, which is conducive to the discharge of the concentrated deposited slag.

[0054] In some embodiments, Figure 4 As shown, the cleaning device 100 further includes a liquid inlet valve 30. The liquid inlet valve 30 is disposed at the liquid inlet port 221 and is configured to open or close the liquid inlet port 221. Exemplarily, the type of the liquid inlet valve 30 may be a pneumatic valve or a solenoid valve.

[0055] In addition, if Figure 4 As shown, the cleaning device 100 further includes a drain valve 40. The drain valve 40 is disposed at the drain port 211, and the drain valve 40 is used to open or close the drain port 211. Exemplarily, the type of the drain valve 40 may be the same as the type of the inlet valve 30, for example, the type of the drain valve 40 may be a pneumatic valve or a solenoid valve.

[0056] In the above embodiment, by controlling the opening or closing of the drain valve 40 and the opening or closing of the inlet valve 30 , the cleaning component 2 can be cleaned and moisturized, or the cleaning tank 20 can be self-cleaned.

[0057] In some embodiments, the cleaning and moisturizing process of the cleaning component 2 can be described as follows: the robot arm 10 drives the cleaning component 2 to move into the cleaning tank 20, then opens the liquid inlet valve 30, closes the liquid discharge valve 40, and pours the cleaning liquid into the cleaning tank 20 through the liquid inlet valve 30, and waits until the liquid level in the cleaning tank 20 rises to a first height, and then closes the liquid inlet valve 30. At this time, the cleaning component 2 is immersed in the cleaning liquid, and under the action of the cleaning liquid, the crystal slag will fall off the cleaning component 2 and deposit at the bottom of the cleaning tank 20.

[0058] The plane where the end surface of the side wall 22 close to the bottom wall 21 is located is taken as the reference plane P, and the first height specifically refers to the height of the liquid level in the cleaning tank 20 compared to the reference plane P.

[0059] On the basis of the above embodiment, in order to improve the cleanliness of the cleaning liquid in the cleaning tank 20, the cleaning liquid in the cleaning tank 20 can be replaced at a preset period. The preset period can be set according to actual conditions, for example, the preset period can be 30 minutes.

[0060] In other embodiments, the cleaning and moisturizing process of the cleaning component 2 can also be described as follows: the robot arm 10 drives the cleaning component 2 to move into the cleaning tank 20, then opens the liquid inlet valve 30, and closes the liquid discharge valve 40, and pours the cleaning liquid into the cleaning tank 20 through the liquid inlet valve 30, and waits until the liquid level in the cleaning tank 20 rises to the first height, opens the liquid discharge valve 40, and keeps the liquid inlet valve 30 open. At this time, the cleaning component 2 is immersed in the cleaning liquid, and under the flushing effect of the cleaning liquid, the crystal slag will fall off the cleaning component 2, and can be continuously discharged from the cleaning tank from the liquid discharge port 211 to improve the cleanliness and fluidity of the cleaning liquid.

[0061] In some embodiments, the self-cleaning process of the cleaning tank 20 can be described as follows: open the liquid inlet valve 30 and close the liquid drain valve 40, pour cleaning liquid into the cleaning tank 20 through the liquid inlet valve 30, wait until the liquid level in the cleaning tank 20 rises to a first height, close the liquid inlet valve 30, and open the liquid drain valve 40, wait until the liquid level in the cleaning tank 20 drops to a second height, and close the liquid drain valve 40.

[0062] The plane where the end surface of the side wall 22 close to the bottom wall 21 is located is the reference plane P, and the second height specifically refers to the height of the liquid level in the cleaning tank 20 compared to the reference plane P. The second height can be a negative value, while the first height is a positive value.

[0063] In some embodiments, Figure 4 As shown, the cleaning device 100 further includes a first liquid level sensor 50 and a second liquid level sensor 60 .

[0064] The first liquid level sensor 50 is disposed on the side wall 22. Along the first direction X, a distance H3 between the first liquid level sensor 50 and an end surface of the side wall 22 close to the bottom wall 21 is greater than or equal to half of the size H2 of the side wall 22.

[0065] For example, the distance H3 between the first liquid level sensor 50 and an end surface of the side wall 22 close to the bottom wall 21 is greater than or equal to one half, two thirds, three quarters, four fifths or five sixths of the size H2 of the side wall 22 .

[0066] The first liquid level sensor 50 is configured to send a first sensing signal when it detects that the liquid level in the cleaning tank 20 rises to a first height. Based on this, the height of the first liquid level sensor 50 is the same as the first height; of course, the first height can also be slightly higher or lower than the height of the first liquid level sensor 50, as long as the first height is set within the sensing range of the first liquid level sensor 50.

[0067] In this way, by receiving the first sensing signal, the liquid level of the cleaning liquid in the cleaning tank 20 can be known in time, and then the liquid inlet valve 30 can be closed, reducing the risk of the cleaning liquid overflowing the cleaning tank 20 due to failure to close the liquid inlet valve 30 in time.

[0068] like Figure 4 As shown, the second liquid level sensor 60 is disposed above the liquid discharge port 211. The second liquid level sensor 60 is configured to detect that the liquid level in the cleaning tank 20 drops to a second height and send out a second sensing signal.

[0069] In this way, by receiving the second sensing signal, the liquid level of the cleaning liquid in the cleaning tank 20 can be timely known, and the drain valve 40 can be closed.

[0070] In some embodiments, Figure 4 As shown, the cleaning device 100 further includes a controller 70. The controller 70 is electrically connected to the first liquid level sensor 50, the second liquid level sensor 60, the liquid inlet valve 30 and the liquid outlet valve 40.

[0071] The controller 70 is configured to control the liquid inlet valve 30 to open, and to control the liquid inlet valve 30 to close according to the first sensing signal of the first liquid level sensor 50 .

[0072] By configuring in this manner, the liquid inlet valve 30 can be opened or closed automatically.

[0073] like Figure 4 As shown, the controller 70 is further configured to control the drain valve 40 to open, and control the drain valve 40 to close according to the second sensing signal of the second liquid level sensor 60 .

[0074] By configuring in this manner, the drain valve 40 can be opened or closed automatically.

[0075] The following describes how the controller 70 realizes the cleaning and moisturizing of the cleaning component 2 or the self-cleaning of the cleaning tank 20.

[0076] In some examples, the cleaning and moisturizing process of the cleaning component 2 can be described as follows: the robotic arm 10 drives the cleaning component 2 to move into the cleaning tank 20, and then the controller 70 controls the liquid inlet valve 30 to open and the liquid discharge valve 40 to close, and the cleaning liquid is poured into the cleaning tank 20 through the liquid inlet valve 30. When the liquid level in the cleaning tank 20 rises to a first height, the controller 70 controls the liquid inlet valve 30 to close.

[0077] In other examples, the cleaning and moisturizing process of the cleaning component 2 can also be described as follows: the robot arm 10 drives the cleaning component 2 to move into the cleaning tank 20, and then the controller 70 opens the liquid inlet valve 30 and controls the liquid discharge valve 40 to be closed, and the cleaning liquid is poured into the cleaning tank 20 through the liquid inlet valve 30. When the liquid level in the cleaning tank 20 rises to a first height, the controller 70 controls the liquid discharge valve 40 to open and maintains the liquid inlet valve 30 open.

[0078] In some examples, the self-cleaning process of the cleaning tank 20 can be described as follows: the controller 70 controls the liquid inlet valve 30 to open, and controls the liquid drain valve 40 to close, and pours cleaning liquid into the cleaning tank 20 through the liquid inlet valve 30. When the liquid level in the cleaning tank 20 rises to a first height, the controller 70 controls the liquid inlet valve 30 to close, and controls the liquid drain valve 40 to open. When the liquid level in the cleaning tank 20 drops to a second height, the controller 70 controls the liquid drain valve 40 to close.

[0079] In some embodiments, Figure 4 As shown, the controller 70 is further configured to send out an alarm signal if the first sensing signal is not received within a first preset time after the inlet valve 30 is opened and the drain valve 40 is closed. The first preset time refers to the time required from the opening of the inlet valve 30 and the closing of the drain valve 40 (i.e., the start of the injection of cleaning liquid into the cleaning tank 20) ​​to the rise of the liquid level in the cleaning tank 20 to the first height under normal circumstances.

[0080] That is, during the process of injecting cleaning liquid into the cleaning tank 20, if the liquid level in the cleaning tank 20 does not rise to the first height within the first preset time, the controller 70 sends an alarm signal. Upon receiving the alarm signal, the staff checks the condition of the cleaning tank 20, for example, whether the cleaning tank 20 is broken.

[0081] The following describes two situations in which the liquid level in the cleaning tank 20 fails to rise to the first height within the first preset time and the controller 70 issues an alarm signal.

[0082] Exemplarily, the rupture of the side wall 22 or the bottom wall 21 causes the controller 70 to fail to receive the first sensing signal within the first preset time, that is, the liquid level in the cleaning tank 20 does not rise to the first height within the first preset time.

[0083] Or, illustratively, leakage occurs in the liquid inlet 221, resulting in the controller 70 not receiving the first sensing signal within the first preset time, that is, the liquid level in the cleaning tank 20 does not rise to the first height within the first preset time.

[0084] In some examples, the controller 70 is further configured to send an alarm signal if the second sensing signal is not received within a second preset time when the inlet valve 30 is closed and the drain valve 40 is opened. The second preset time refers to the time required from the closing of the inlet valve 30 and the opening of the drain valve 40 (i.e., the cleaning tank 20 starts to drain the cleaning liquid) to the liquid level in the cleaning tank 20 dropping to the second height under normal circumstances. The second preset time may be the same as or different from the first preset time.

[0085] That is, during the process of discharging the cleaning liquid from the cleaning tank 20, if the liquid level in the cleaning tank 20 does not drop to the second height within the second preset time, the controller 70 sends an alarm signal. Upon receiving the alarm signal, the staff checks the condition of the cleaning tank 20, for example, whether the cleaning tank 20 is blocked.

[0086] The following describes a situation in which the liquid level in the cleaning tank 20 does not drop to the second height within the second preset time and the controller 70 issues an alarm signal.

[0087] Exemplarily, the crystal slag blocks the drain port 211, causing the controller 70 to fail to receive the second sensing signal within the second preset time, that is, the liquid level in the cleaning tank 20 does not drop to the second height within the second preset time.

[0088] In some embodiments, Figure 4 As shown, the cleaning device 100 further includes an alarm device 110. The alarm device 110 is electrically connected to the controller 70, and the controller 70 is configured to send an alarm signal to the alarm device 110. The controller 70 receives the alarm signal and sounds an alarm. When the staff hears the alarm, they check the condition of the cleaning tank 20.

[0089] In some embodiments, Figure 4 As shown, the cleaning device 100 further includes a plurality of nozzles 80. For example, the cleaning device 100 includes three, four or five nozzles 80, and the implementation of the present disclosure is not specifically limited here.

[0090] like Figure 4As shown, a plurality of nozzles 80 are disposed on the side wall 22 and are spaced apart along the circumference of the side wall 22. For example, the plurality of nozzles 80 are equally spaced apart along the circumference of the side wall 22. With respect to the plane where the end surface of one end of the side wall 22 close to the bottom wall 21 is located, the height of the plurality of nozzles 80 is higher than the height of the liquid inlet 221.

[0091] Arranged in this way, multiple nozzles 80 can flush the side of the cleaning component 2, and can flush the slag on the side of the cleaning component 2 into the cleaning tank 20, so as to reduce the amount of slag on the side of the cleaning component 2 and reduce the risk of the slag scratching the wafer 1.

[0092] In some examples, such as Figure 4 and Figure 5 As shown, the plane where the end surface of the side wall 22 close to the bottom wall 21 is located is taken as the reference plane P. In the orthographic projection to the reference plane P, the spraying range of the plurality of nozzles 80 covers the circumference of the cleaning component 2. The first direction X is perpendicular to the reference plane P.

[0093] Arranged in this manner, the plurality of spray heads 80 can rinse all sides of the cleaning member 2 .

[0094] For example, Figure 4 and Figure 5 As shown, the cleaning device 100 includes three nozzles 80, and the three nozzles 80 are evenly spaced along the circumference of the side wall 22, and the spray angle θ of the nozzle 80 is greater than or equal to 60°. For example, the spray angle θ of the nozzle 80 is greater than or equal to 60°, 70° or 80°, which is not specifically limited in the embodiments of the present disclosure.

[0095] In some embodiments, Figure 4 As shown, the spray head 80 is also connected to the controller 70, and the controller 70 is also configured to control the opening or closing of the spray head 80. In this way, the automatic opening or closing of the spray head 80 is achieved.

[0096] In some embodiments, Figure 4 As shown, the angle between the spray direction of the nozzle 80 and the side wall 22 is 30° to 60°. In this way, the spray direction of the nozzle 80 is tilted downward, which can reduce the risk of the sprayed cleaning liquid splashing outside the cleaning tank 20.

[0097] In some embodiments, Figure 4 As shown, the plurality of nozzles 80 are farther from the bottom wall 21 than the first liquid level sensor 50. In this way, the plurality of nozzles 80 are arranged higher than the height of the liquid level in the cleaning tank 20, so as to form an oblique downward spraying direction, and the nozzles 80 will not be soaked in the cleaning liquid, so that the service life of the nozzles 80 can be improved.

[0098] The embodiment of the present disclosure also provides a cleaning method of the cleaning device 100. Figure 6 As shown, the above cleaning method includes: step S100 to step S400.

[0099] Step S100 , after the cleaning component 2 wipes the ground wafer 1 , the cleaning component 2 is moved into the cleaning tank 20 .

[0100] In some embodiments, the robot arm 10 drives the cleaning component 2 to move into the cleaning tank 20. For example, the controller 70 controls the robot arm 10 to drive the cleaning component 2 to move into the cleaning tank 20.

[0101] Step S400, cleaning and moisturizing the cleaning component 2.

[0102] Exemplarily, step S400 includes steps S410 to S450.

[0103] Step S410 , open the liquid inlet valve 30 , close the liquid discharge valve 40 , and inject cleaning liquid into the cleaning tank 20 .

[0104] In some embodiments, a worker manually opens the liquid inlet valve 30 and closes the liquid outlet valve 40 .

[0105] In other embodiments, the cleaning device 100 includes a controller 70, and the controller 70 is electrically connected to the liquid inlet valve 30 and the liquid discharge valve 40. The controller 70 can control the liquid inlet valve 30 to open and the liquid discharge valve 40 to close.

[0106] Step S420: the liquid level in the tank to be cleaned 20 rises to a first height, the liquid inlet valve 30 is closed, and the cleaning component 2 is immersed in the cleaning liquid.

[0107] In some embodiments, the staff observes the liquid level in the cleaning tank 20 , and when the liquid level in the cleaning tank 20 rises to a first height, the staff closes the liquid inlet valve 30 .

[0108] In other embodiments, the cleaning device 100 includes a first liquid level sensor 50 , which detects that the liquid level in the cleaning tank 20 rises to a first height and sends a first sensing signal. The staff receives the first sensing signal and closes the liquid inlet valve 30 .

[0109] In some other embodiments, the cleaning device 100 further includes a controller 70, which is also electrically connected to the first liquid level sensor 50. The first liquid level sensor 50 detects that the liquid level in the cleaning tank 20 rises to a first height and sends a first sensing signal. The controller 70 receives the first sensing signal and controls the liquid inlet valve 30 to close.

[0110] Step S430: determine whether the grinding device is in working state.

[0111] If so, execute step S440.

[0112] Step S440 , after soaking, the cleaning component 2 moves to the surface of the ground wafer 1 to wipe the wafer 1 .

[0113] Exemplarily, the soaking time of the cleaning component 2 may be a third preset time, for example, the third preset time may be 30 minutes. The purpose of setting the soaking time of the cleaning component 2 to the third preset time is to allow the crystal slag on the cleaning component 2 to be separated from the cleaning component 2 as much as possible and enter the cleaning liquid. The third preset time may be set according to actual conditions. When the cleaning component 2 is moved to the ground wafer 1, the cleaning liquid in the cleaning tank 20 is discharged at the same time.

[0114] The grinding device being in working state means that the grinding device is grinding the wafer 1 , which means that there will be wafers 1 that need to be wiped.

[0115] If not, that is, the grinding device is in an idle state, step S450 is executed.

[0116] Step S450: keep the cleaning component 2 immersed in the cleaning liquid, and replace the cleaning liquid in the cleaning tank at a preset period.

[0117] The purpose of keeping the cleaning component 2 immersed in the cleaning liquid is to keep the cleaning component 2 in a moisturizing state so that the cleaning component 2 can be used in time when a wafer 1 needs to be wiped. The preset period can be set according to actual conditions. For example, the preset period can be 30 minutes.

[0118] The grinding device being in an idle state means that the grinding device is not currently grinding a wafer and there is currently no wafer that needs to be wiped.

[0119] In some embodiments, Figure 7 As shown, between S100 (after the cleaning component 2 wipes the polished wafer 1, the robot arm 10 drives the cleaning component 2 to move into the cleaning tank 20) ​​and S400 (cleaning and moisturizing the cleaning component 2), the cleaning method also includes: steps S200 to S300.

[0120] Step S200 , opening the plurality of nozzles 80 to rinse the cleaning component 2 .

[0121] The time for the multiple nozzles 80 to wash the side of the cleaning component 2 can be set according to actual conditions. For example, the time for the multiple nozzles 80 to wash the side of the cleaning component 2 can be 10 seconds to 15 seconds.

[0122] In some embodiments, the staff turns on the plurality of spray heads 80 , and the plurality of spray heads 80 cleans the sides of the cleaning component 2 .

[0123] In other embodiments, the cleaning device 100 includes a controller 70, and the controller 70 is electrically connected to a plurality of nozzles 80. The controller 70 can control the plurality of nozzles 80 to open, and the plurality of nozzles 80 clean the side of the cleaning component 2.

[0124] Step S300 , performing self-cleaning on the cleaning tank 20 .

[0125] Exemplarily, step S300 includes steps S310 to S330.

[0126] Step S310 , open the liquid inlet valve 30 , and close the liquid discharge valve 40 , and inject the cleaning liquid into the cleaning tank 20 .

[0127] Step S320 , the liquid level in the tank to be cleaned 20 rises to a first height, the liquid inlet valve 30 is closed, and the liquid discharge valve 40 is opened.

[0128] Step S330 , the liquid level in the tank to be cleaned 20 drops to a second level, and the drain valve 40 is closed.

[0129] In some embodiments, the staff observes the liquid level in the cleaning tank 20 , and when the liquid level in the cleaning tank 20 drops to the second height, the staff manually closes the drain valve 40 .

[0130] In other embodiments, the cleaning device 100 includes a second liquid level sensor 60 , which detects that the liquid level in the cleaning tank 20 drops to a second height and sends a second sensing signal. The staff closes the drain valve 40 after receiving the second sensing signal.

[0131] In some other embodiments, the cleaning device 100 further includes a controller 70, which is also electrically connected to the second liquid level sensor 60. The second liquid level sensor 60 detects that the liquid level in the cleaning tank 20 drops to a second height and sends a second sensing signal. The controller 70 receives the second sensing signal and controls the drain valve 40 to close.

[0132] In the description of this specification, specific features, structures, materials or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

[0133] The above is only a specific embodiment of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or substitutions that can be thought of by any person skilled in the art within the technical scope disclosed in the present disclosure should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A cleaning device, characterized in that: include: A cleaning tank, the cleaning tank comprising a bottom wall and a side wall arranged around the bottom wall; the side wall is provided with a liquid inlet, the bottom wall is provided with a liquid discharge port, the bottom wall is funnel-shaped, and the liquid discharge port is located at the center of the bottom wall; along a first direction, the distance between the liquid inlet and an end surface of the side wall close to the bottom wall is greater than half of the size of the side wall; the first direction is perpendicular to the plane where the end surface of the side wall close to the bottom wall is located; The liquid inlet valve is arranged at the liquid inlet; the liquid discharge valve is arranged at the liquid discharge outlet.

2. The cleaning device according to claim 1, characterized in that: The cleaning device also includes: A first liquid level sensor is disposed on the side wall; along the first direction, a distance between the first liquid level sensor and an end surface of the side wall close to the bottom wall is greater than or equal to one half of the size of the side wall; The second liquid level sensor is arranged above the liquid discharge port.

3. The cleaning device according to claim 2, characterized in that: The cleaning device also includes: A controller, electrically connected to the first liquid level sensor, the second liquid level sensor, the liquid inlet valve and the liquid discharge valve; The controller is configured to control the liquid inlet valve to open and control the liquid inlet valve to close according to a first sensing signal from the first liquid level sensor; and control the liquid discharge valve to open and control the liquid discharge valve to close according to a second sensing signal from the second liquid level sensor.

4. The cleaning device according to claim 3, characterized in that: The cleaning device further comprises: an alarm device, the alarm device being electrically connected to the controller; the controller is further configured to issue an alarm signal if the first sensing signal is not received within a first preset time after the inlet valve is opened and the drain valve is closed; and If the second sensing signal is not received within a second preset time when the inlet valve is closed and the drain valve is opened, an alarm signal is issued.

5. The cleaning device according to any one of claims 1 to 4, characterized in that: The cleaning device also includes: A plurality of nozzles are arranged on the side wall and spaced apart along the circumference of the side wall; relative to a plane where an end surface of the side wall close to the bottom wall is located, the height of the plurality of nozzles is higher than the height of the liquid inlet.

6. The cleaning device according to claim 5, characterized in that: The included angle between the spraying direction of the spray head and the side wall is 30° to 60°, and the spraying range of the multiple spray heads covers the entire circumference of the cleaning component.

7. The cleaning device according to claim 6, characterized in that: The plurality of nozzles are farther away from the bottom wall than the first liquid level sensor.

8. A wafer thinning device, characterized in that: The wafer thinning equipment comprises: A grinding device configured to grind the wafer to be thinned; The cleaning device according to any one of claims 1 to 7 is configured to wipe the polished wafer with a cleaning member, and move the cleaning member to a cleaning tank of the cleaning device for cleaning after wiping.

9. A cleaning method using the cleaning device according to any one of claims 1 to 7, characterized in that: The cleaning method comprises: After the cleaning component wipes the ground wafer, the cleaning component is moved into the cleaning tank; Closing the drain valve and opening the inlet valve to inject cleaning liquid into the cleaning tank; When the liquid level in the cleaning tank rises to a first height, the liquid inlet valve is closed, and the cleaning component is immersed in the cleaning liquid; When the grinding device is in working state, the cleaning component moves to the surface of the ground wafer after soaking to wipe the wafer; When the grinding device is in an idle state, the cleaning component is kept immersed in the cleaning liquid, and the cleaning liquid in the cleaning tank is replaced at a preset period.

10. The cleaning method according to claim 9, characterized in that: Before immersing the cleaning component in the cleaning liquid, the cleaning method further includes: opening a plurality of nozzles to rinse the cleaning component; and injecting the cleaning liquid into the cleaning tank after self-cleaning the cleaning tank.

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