Driven mechanism for wafer cleaning device and wafer cleaning device

Abstract

The invention discloses a driven mechanism for a wafer cleaning device and the wafer cleaning device, and the driven mechanism comprises a base which is hollow and forms a mounting cavity; the rotating shaft is rotatably connected to the mounting cavity through a rotating transmission assembly, and the first end of the rotating shaft extends out of the base; the wafer bearing unit is concentrically and coaxially connected to the rotating shaft and is used for bearing a wafer; the structural part is in sealed connection with the base, and part of the structural part extends into the mounting cavity and can abut against the rotary transmission assembly; the sensor assembly is partially connected with the rotating shaft and used for monitoring the number of turns of rotation of the rotating shaft relative to the base; the wafer rotates to drive the wafer bearing unit to rotate, and the rotating shaft rotates synchronously to drive the sensor assembly to rotate so as to monitor the number of revolutions of the wafer. The wafer rotates to drive the wafer bearing unit to rotate, the rotating shaft rotates synchronously and is matched with the sensor assembly to monitor the rotating speed of the wafer, the mass and torque of the rotating shaft are small, the rotational inertia of the rotating shaft and the wafer bearing unit is reduced, monitoring of the rotating speed of the wafer is more accurate, and the cleaning effect is better.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor integrated circuit chip manufacturing technology, and in particular relates to a driven mechanism for a wafer cleaning apparatus and a wafer cleaning apparatus. Background Technology

[0002] Chemical mechanical polishing (CMP) is an ultra-precision surface finishing process that achieves global planarization. Because the large amounts of chemical reagents and abrasives used in CMP leave significant residues of abrasive particles and byproducts on the wafer surface after polishing, these contaminants need to be removed to prevent their re-entry before further processing. Therefore, multiple surface cleaning processes are required during wafer manufacturing to remove contaminants such as metal ions, atoms, organic matter, and particles adhering to the wafer surface. The cleaning process comprises three units: a mega-sweep unit, a brushing unit, and a drying unit. The brushing unit utilizes mechanical action of roller brushes to detach contaminants from the wafer surface into the cleaning solution, and also employs a chemical reaction between the cleaning solution and the contaminants on the wafer surface to dissolve them.

[0003] Existing wafer cleaning equipment typically places the wafer inside a brushing device. A drive wheel rotates the wafer while a brush simultaneously cleans it. Meanwhile, a driven wheel rotates with the wafer and monitors its rotational speed. During this process, the driven wheel's speed can drop, directly impacting the cleaning effect. Furthermore, the current structure's bearings operate in a dry-running state without lubrication, resulting in high overall structural resistance. Additionally, the rotating structure is heavy, leading to a large moment of inertia and significant starting resistance. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the present invention provides a driven mechanism for a wafer cleaning apparatus and a wafer cleaning apparatus, which uses the rotation of a rotating shaft to monitor the wafer rotation speed, greatly reducing the moment of inertia and making the wafer rotation speed monitoring more accurate.

[0005] The technical solution adopted by this invention to solve its technical problem is: a driven mechanism for a wafer cleaning apparatus, comprising: The base is used to fix and connect to the wafer cleaning device, and the interior of the base is hollow to form an installation cavity; A rotating shaft is rotatably connected to the mounting cavity via a rotational transmission assembly, with its first end extending from the base; A wafer support unit is concentrically and coaxially connected to the first end of the rotating shaft and is used to support the wafer; A structural component, sealed to the base, at least partially extending into the mounting cavity and abutting against the rotary transmission assembly; A sensor assembly, at least partially connected to the rotating shaft, is used to monitor the number of rotations of the rotating shaft relative to the base; When the wafer rotates, causing the wafer support unit to rotate, the rotating shaft rotates synchronously, causing at least a portion of the sensor assembly to rotate, in order to monitor the number of wafer rotations.

[0006] Furthermore, the wafer support unit includes a sleeve portion connected to the rotation shaft, a connecting portion extending radially outward from the end of the sleeve portion, a fixing portion cooperating with the connecting portion, and a slot member clamped between the connecting portion and the fixing portion. The slot member is used to contact the wafer, and the sleeve portion covers the periphery of the base in both the radial and axial directions.

[0007] Furthermore, the rotary transmission assembly includes a first bearing, a second bearing, and a limiting member abutting between the first bearing and the second bearing.

[0008] Furthermore, the slot component is radially corresponding to the limiting component.

[0009] Furthermore, the sensor assembly includes a metal body and a sensor that cooperates with the metal body. The metal body is connected to the second end of the rotating shaft, and the sensor is disposed on the structural component.

[0010] Furthermore, a liquid passage is provided, which includes at least a liquid inlet channel located in the structural component, at least two branch channels diverted from the liquid inlet channel, a liquid storage channel located in the mounting cavity corresponding to the rotary transmission component, and a detour channel, wherein the bottom of the liquid storage channel is at a height less than the inlet of the detour channel.

[0011] Furthermore, the liquid flow rate in the inlet channel is 30-70 ml / min, and the liquid flow rate in the branch channel is 7.5-17.5 ml / min.

[0012] Furthermore, the liquid passage is provided with a dynamic sealing ring at its end and a one-way valve at its beginning to close the liquid passage and fill the liquid storage channel with liquid.

[0013] Furthermore, the moment of inertia of the rotating shaft and the wafer support unit is less than 35 kg*mm. 2 .

[0014] The present invention also discloses a wafer cleaning apparatus, including a cleaning chamber, a drive wheel mechanism disposed in the cleaning chamber for driving the wafer to rotate, a brushing mechanism for cleaning the wafer surface, and the aforementioned driven mechanism.

[0015] The beneficial effects of this invention are: 1) The wafer rotation drives the wafer support unit to rotate, so that the rotating shaft rotates synchronously and cooperates with the sensor assembly to monitor the wafer rotation speed, while the base and structural components do not rotate. The mass and torque of the rotating shaft are smaller, and the rotational inertia of the rotating shaft and the wafer support unit is greatly reduced, making the monitoring of the wafer rotation speed more accurate. This allows for better cleaning results through wafer transfer adjustments; 2) A liquid path is designed to lubricate the rotary transmission assembly with water, reducing the bearing friction coefficient, helping the bearing to dissipate heat better, and extending the service life of the rotary transmission assembly; 3) Liquid... The flow rate was suppressed three times in the channel to reduce the impact of water lubrication on the rotation of the rotating shaft and ensure the accuracy of wafer speed monitoring; 4) The rigid body rotational inertia of the rotating shaft and the wafer support unit is small, and only lower static friction is required to make it rotate, reducing the wear of related consumables, improving stability, reducing consumable costs, and increasing the output per unit time; 5) The slot is set radially corresponding to the limiting component, and the center of gravity of the driven mechanism is close to the bottom of the wafer to ensure that the first bearing and the second bearing are relatively balanced in force, reduce the problem of excessive wear of one side bearing caused by off-center load, and increase the output per unit time. Attached Figure Description

[0016] Figure 1 This is a partial perspective view of the wafer cleaning apparatus of the present invention.

[0017] Figure 2 A cross-sectional view of the driven mechanism involved in this invention. Figure 1 .

[0018] Figure 3 A cross-sectional view of the driven mechanism involved in this invention. Figure 2 .

[0019] Figure 4 The three-dimensional driven mechanism of the present invention Figure 1 .

[0020] Figure 5 The structural component involved in this invention is a three-dimensional Figure 1 .

[0021] Figure 6 The structural component involved in this invention is a three-dimensional Figure 2 .

[0022] Figure 7 This is a perspective view of the fastener involved in the present invention.

[0023] Figure 8 This is a cross-sectional view of the fastener and metal body assembly involved in the present invention.

[0024] Figure 9 This is a side view of the driven mechanism involved in the present invention.

[0025] Figure 10 The three-dimensional driven mechanism of the present invention Figure 2 .

[0026] Figure 11 This is a partial perspective view of the base and wafer support unit involved in the present invention.

[0027] Figure 12 This is a partial perspective view of the driven mechanism involved in the present invention.

[0028] Figure 13 A cross-sectional view of the driven mechanism involved in this invention. Figure 3 .

[0029] Figure 14 A cross-sectional view of the driven mechanism involved in this invention. Figure 4 .

[0030] Among them, 1-wafer cleaning device, 11-cleaning box, 12-drive wheel mechanism, 13-brushing mechanism, 2-base, 21-mounting cavity, 3-rotating shaft, 31-first end of rotating shaft, 32-second end of rotating shaft, 4-rotational transmission assembly, 41-first bearing, 42-second bearing, 43-limiting component, 5-wafer support unit, 51-sleeve part, 52-connecting part, 53-fixing part, 54-slot part, 541-slot opening, 55-inclined guide surface, 6-structural component, 61-external conduit, 7-sensor assembly, 71-metal body, 72-sensor, 721-sensor press-fit component, 73-fixing component, 8-liquid passage, 81-liquid inlet channel, 82-branch channel, 83-liquid storage channel, 84-detour channel, 85-dynamic sealing ring, 9-wafer. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0032] like Figures 2-4 As shown, a driven mechanism for a wafer cleaning apparatus includes a base 2, a rotating shaft 3, a wafer support unit 5, a structural component 6 sealed to the base 2, and a sensor assembly 7.

[0033] like Figure 11 , Figure 12As shown, the base 2 is used to fix the driven mechanism to the wafer cleaning device 1. The interior of the base 2 is hollow to form a mounting cavity 21. One end of the mounting cavity 21 is completely open. A part of the structural component 6 extends into the mounting cavity 21 from this end and is sealed to the base 2. Specifically, the outer ring of the structural component 6 can be detachably assembled and connected to the outer ring of the end of the base 2. The other end of the mounting cavity 21 is partially open.

[0034] The rotating shaft 3 is rotatably connected to the mounting cavity 21 via the rotary transmission assembly 4, and the first end 31 of the rotating shaft 3 extends out of the base 2 from a partially open position in the mounting cavity 21. In this embodiment, the rotary transmission assembly 4 includes a first bearing 41 and a second bearing 42 sleeved on the outside of the rotating shaft 3, and a limiting member 43 abutting between the first bearing 41 and the second bearing 42. The first bearing 41 abuts against the inner end face of the base 2. The structural member 6 extends into the mounting cavity 21 and abuts against the second bearing 42 of the rotary transmission assembly 4, thereby securely assembling the first bearing 41, the limiting member 43, and the second bearing 42 within the mounting cavity 21, ensuring the stable installation of the rotary transmission assembly 4, preventing axial movement of the first bearing 41 and the second bearing 42 on the rotating shaft 3, and ensuring their positional stability.

[0035] The wafer support unit 5 is concentrically and coaxially connected to the first end 31 of the rotating shaft 3, and its function is to support the wafer 9. In this embodiment, the wafer support unit 5 includes a sleeve portion 51 connected to the first end 31 of the rotating shaft 3, a connecting portion 52 extending radially outward from the end of the sleeve portion 51 toward the structural member 6, a fixing portion 53 cooperating with the connecting portion 52, and a slot member 54 clamped between the connecting portion 52 and the fixing portion 53. The slot member 54 is used to contact the wafer 9, and the sleeve portion 51 covers the periphery of the base 2 radially and axially.

[0036] like Figures 10-12 As shown, the fixing part 53 is a hollow annular structure, which is sleeved on the sleeve part 51 and fixedly assembled with the connecting part 52, thereby clamping the slot member 54 between the two. In order to facilitate the insertion of the wafer 9 into the slot member 54 and to provide better support for the wafer 9, the opposing sides of the fixing part 53 and the connecting part 52 are formed with inclined guide surfaces 55, and the end of the inclined guide surface 55 is connected with the slot opening 541 of the slot member 54.

[0037] There is a certain amount of friction between the slot 54 and the wafer 9. When the wafer 9 rotates at a certain speed, the slot 54 will also rotate synchronously at the same speed, and the corresponding connecting part 52 will also rotate synchronously at the same speed, thereby driving the rotating shaft 3 to rotate synchronously. At this time, the rotary transmission assembly 4 provides good support and transmission for the rotating shaft 3, reducing the vibration and offset of the rotating shaft 3 and ensuring the smooth operation of the rotating shaft 3. The slot 54 is a consumable used to fix the wafer 9 and needs to be replaced periodically. The detachable assembly of the fixing part 53 and the connecting part 52 makes it easy to replace the slot 54.

[0038] Regarding the relative position of the connecting part 52 and the base 2, the slot 54 should be radially aligned with the limiting member 43, and preferably the slot 541 of the slot 54 should be aligned with the middle part of the limiting member 43.

[0039] like Figure 3 , Figure 7 , Figure 8 As shown, at least a portion of the sensor assembly 7 is connected to the rotating shaft 3 and is used to monitor the number of rotations of the rotating shaft 3 relative to the base 2. In this embodiment, the sensor assembly 7 includes a metal body 71 and a sensor 72 that cooperates with the metal body 71. The metal body 71 is connected to the second end 32 of the rotating shaft 3, and the sensor 72 is disposed on the structural member 6.

[0040] Specifically, sensor 72 is a proximity sensor, which is fixedly connected to structural component 6 by screws by sensor press-fit component 721. Sensor 72 uses electromagnetic induction to detect metal component 71. There is a coil inside sensor 72, which generates a high-frequency magnetic field when energized. When metal component 71 enters the electromagnetic field range, eddy currents are generated inside metal component 71, causing the coil oscillation frequency to change. Sensor 72 outputs a signal by detecting this change.

[0041] In this embodiment, the metal part 71 is made of sheet metal and is fixedly connected to the fixing member 73. The fixing member 73 is made of plastic. There are two metal parts 71, which are embedded in the fixing member 73 and fixedly connected to it. For every half-turn rotation of the fixing member 73 around the rotating shaft 3, the sensor 72 can detect and output a signal. The fixing member 73 is sleeved on the outer side of the end of the rotating shaft 3 and abuts against the second bearing 42 and the structural member 6, respectively.

[0042] like Figure 1 As shown, a wafer cleaning apparatus includes a cleaning chamber 11, a drive wheel mechanism 12 disposed inside the cleaning chamber 11 for driving the wafer 9 to rotate, a brushing mechanism 13 for cleaning the surface of the wafer 9, and the aforementioned driven mechanism. The number of drive wheel mechanisms 12 is two, which are respectively disposed on both sides of the driven mechanism.

[0043] The principle of wafer 9 rotation speed detection is as follows: wafer 9 is inserted into the slot 541 of the slot 54. The slot 54 is fixed to the rotating shaft 3 through the connecting part 52 and the fixing part 53. The rotating shaft 3 passes through the rotary transmission assembly 4. The outer ring of the rotary transmission assembly 4 will not rotate under the action of the structural part 6. The metal part 71 rotates together with the rotating shaft 3. The wafer 9 rotates under the drive of the active wheel mechanism 12, which drives the rotating shaft 3 to rotate. The fixing part 73 and the metal part 71 rotate together. The sensor 72 can detect the actual rotation speed of the wafer 9 through electromagnetic induction with the metal part 71.

[0044] Because the rotating shaft 3 rotates, the base 2, structural component 6, etc., will not rotate. The moment of inertia of the rotating shaft 3 and the wafer support unit 5 is less than 35 kg*mm. 2 Preferably, the moment of inertia is less than 30 kg*mm. 2 .

[0045] The driven mechanism is also provided with a liquid passage 8, which includes an inlet channel 81 located in the structural member 6, at least two branch channels 82 branching from the inlet channel 81, a storage channel 83 located in the mounting cavity 21 corresponding to the rotary transmission assembly 4, and a detour channel 84 located between the base 2, the sleeve portion 51, and the rotating shaft 3. The bottom of the storage channel 83 is at a height less than the inlet height of the detour channel 84. Figure 2 The inlet of the meandering channel 84 is at height H1, and the bottom of the liquid storage channel 83 is at height H2, with H1 located above H2. The liquid storage channel 83 refers to the area enclosed by the inner wall of the limiting member 43, the outer wall of the rotating shaft 3, the end face of the first bearing 41, and the end face of the second bearing 42. The meandering channel 84 includes the gap between the outer wall of the rotating shaft 3 and the inner wall of the first bearing 41, the gap between the end face of the first bearing 41 and the inner end face of the base 2, the gap between the opening of the rotating shaft 3 and the base 2, the gap between the sleeve portion 51 and the base 2, and the internal gap of the first bearing 41.

[0046] In this embodiment, as Figure 5 , Figure 6 As shown, there are four branch channels 82, which diverge outwards from the inlet channel 81 at an angle, with equal spacing between adjacent branch channels 82. The liquid flow rate in the inlet channel 81 is 30-70 ml / min, and the liquid flow rate in each branch channel 82 is 7.5-17.5 ml / min.

[0047] The structural component 6 is connected to the external conduit 61, so that the liquid is transported from the external conduit 61 to the liquid inlet channel 81 inside the structural component 6 and enters the branch channel 82. It enters the liquid storage channel 83 through the gap between the rotating shaft 3 and the second bearing 42. Once a large amount of liquid accumulates in the liquid storage channel 83, it will enter the detour channel 84 through the gap between the rotating shaft 3 and the first bearing 41.

[0048] Fluid can be continuously supplied through the inlet channel 81, meaning the liquid in the liquid passage 8 is in a continuous flow state; alternatively, a check valve can be installed at the beginning of the liquid passage 8, and a dynamic sealing ring 85 can be installed at the end of the liquid passage 8. The check valve and the dynamic sealing ring 85 work together to close the liquid passage 8, such as... Figure 13 , Figure 14 As shown, after the liquid inlet channel 81 completes one liquid transfer, the liquid storage channel 83 is filled with liquid. Specifically, the space between the first bearing 41 and the second bearing 42 is filled with liquid.

[0049] In this embodiment, the fluid is water. Water flows into the liquid inlet channel 81 of the structural component 6 through the external conduit 61. The water path is divided into four paths through the branch channel 82 and flows into the liquid storage channel 83, that is, into the mounting cavity 21 containing the first bearing 41 and the second bearing 42. At this time, since the water is divided into four branches, its flow rate is suppressed in the first step, that is, the flow rate is reduced for the first time. When the water level in the mounting cavity 21 is level with the inlet of the detour channel 84, the inlet of the detour channel 84 is the gap between the first bearing 41 and the rotating shaft 3. The liquid is discharged through the detour channel 84, and the flow rate is suppressed in the second step, that is, the flow rate is reduced for the second time. Then, the water will flow into the cleaning tank 11 through the detour channel 84, and the flow rate is suppressed in the third step, that is, the flow rate is reduced for the third time.

[0050] The three-stage liquid flow rate suppression enables water lubrication of the first bearing 41 and the second bearing 42 without significantly affecting the rotation of the rotating shaft 3 due to fluid flow, thus ensuring the accuracy of wafer 9 rotation speed monitoring.

[0051] When the liquid passage 8 is closed by using a check valve and a dynamic sealing ring 85, and the liquid storage passage 83 is filled with liquid, the first bearing 41 and the second bearing 42 are water lubricated. At the same time, the water-filled fluid passage 8 can reduce or avoid the disturbance of the bearing balls inside the mounting cavity 21 caused by fluid disturbance, thus ensuring the stability of the overall mechanism.

[0052] The above specific embodiments are used to explain and illustrate the present invention, but not to limit the present invention. Any modifications and changes made to the present invention within the spirit and scope of the claims shall fall within the protection scope of the present invention.

Claims

1. A driven mechanism for a wafer cleaning apparatus, characterized in that: include: The base (2) is used to fix the wafer cleaning device (1) to the wafer cleaning device (1). The base (2) has a hollow interior forming an installation cavity (21). A rotating shaft (3) is rotatably connected to the mounting cavity (21) via a rotational transmission assembly (4), with its first end (31) extending from the base (2); The wafer support unit (5) is concentrically and coaxially connected to the first end (31) of the rotating shaft (3) and is used to support the wafer (9). The structural component (6) is sealed to the base (2), and at least part of it extends into the mounting cavity (21) and can abut against the rotary transmission assembly (4); The sensor assembly (7), at least partially connected to the rotating shaft (3), is used to monitor the number of rotations of the rotating shaft (3) relative to the base (2); When the wafer (9) rotates and drives the wafer support unit (5) to rotate, the rotating shaft (3) rotates synchronously, driving at least part of the sensor assembly (7) to rotate, so as to monitor the number of revolutions of the wafer (9).

2. The driven mechanism for a wafer cleaning apparatus according to claim 1, characterized in that: The wafer support unit (5) includes a sleeve portion (51) connected to the rotating shaft (3), a connecting portion (52) extending radially outward from the end of the sleeve portion (51), a fixing portion (53) cooperating with the connecting portion (52), and a slot member (54) clamped between the connecting portion (52) and the fixing portion (53). The slot member (54) is used to contact the wafer (9). The sleeve portion (51) covers the periphery of the base (2) radially and axially.

3. The driven mechanism for a wafer cleaning apparatus according to claim 2, characterized in that: The rotary transmission assembly (4) includes a first bearing (41), a second bearing (42), and a limiting member (43) abutting between the first bearing (41) and the second bearing (42).

4. The driven mechanism for a wafer cleaning apparatus according to claim 3, characterized in that: The slot (54) is radially corresponding to the limiting member (43).

5. The driven mechanism for a wafer cleaning apparatus according to claim 1, characterized in that: The sensor assembly (7) includes a metal body (71) and a sensor (72) that cooperates with the metal body (71). The metal body (71) is connected to the second end (32) of the rotating shaft (3), and the sensor (72) is located on the structural member (6).

6. The driven mechanism for a wafer cleaning apparatus according to claim 1, characterized in that: A liquid passage (8) is provided, which includes at least an inlet channel (81) located in the structural member (6), at least two branch channels (82) diverted from the inlet channel (81), a liquid storage channel (83) located in the mounting cavity (21) corresponding to the rotary transmission assembly (4), and a detour channel (84), wherein the bottom of the liquid storage channel (83) is at a height less than the inlet of the detour channel (84).

7. The driven mechanism for a wafer cleaning apparatus according to claim 6, characterized in that: The liquid flow rate in the inlet channel (81) is 30-70 ml / min, and the liquid flow rate in the branch channel (82) is 7.5-17.5 ml / min.

8. The driven mechanism for a wafer cleaning apparatus according to claim 6, characterized in that: The liquid passage (8) is provided with a dynamic sealing ring (85) at its end and a one-way valve at its beginning to close the liquid passage (8) and fill the liquid storage channel (83) with liquid.

9. The driven mechanism for a wafer cleaning apparatus according to claim 1, characterized in that: The moment of inertia of the rotating shaft (3) and the wafer support unit (5) is less than 35 kg*mm. 2 .

10. A wafer cleaning apparatus, characterized in that, It includes a cleaning chamber (11), a drive wheel mechanism (12) disposed inside the cleaning chamber (11) for driving the wafer (9) to rotate, a brushing mechanism (13) for cleaning the surface of the wafer (9), and a driven mechanism as described in any one of claims 1-9.

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