Wafer cleaning device

Abstract

The application discloses a wafer cleaning device, which comprises a box body, a supporting assembly for vertically supporting and driving the wafer to rotate, a rolling brush arranged in the box body and used for brushing the surface of the wafer, and a speed measuring assembly arranged at the upper portion of the box body and used for clamping the outer edge of the wafer from above to measure the rotating speed of the brushed wafer.

Description

Technical Field

[0001] This invention belongs to the field of wafer post-processing technology, and more specifically, relates to a wafer cleaning device. Background Technology

[0002] In the semiconductor field, the cleanliness of the wafer surface is one of the important factors affecting the reliability of semiconductor devices. During wafer fabrication processes, such as deposition, plasma etching, photolithography, electroplating, etc., contaminants and / or particles may be introduced into the wafer surface, leading to a decrease in the cleanliness of the wafer surface and a low yield of the manufactured semiconductor devices.

[0003] To achieve a contaminant-free wafer surface, contaminants need to be removed to prevent them from re-entering the wafer surface before the manufacturing process. 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.

[0004] Existing cleaning technologies employ a roller brush method for cleaning wafers. The working principle is as follows: the wafer is rotated, and cleaning solutions such as deionized water and chemical solutions are supplied to the wafer from a supply nozzle, while the roller brush slides into contact with the wafer. The wafer surface is cleaned through friction between the roller brush and the wafer in the presence of the cleaning solution.

[0005] In the vertical brush cleaning technology for wafers, the two drive wheels and one test wheel are all located on the same side (bottom) of the wafer's center. The wafer rotates due to the friction generated by its own weight pressing on the two drive wheels. At the same time, the friction generated between the wafer and the speed measuring wheel drives the speed measuring wheel to rotate, and the sensor in the speed measuring wheel monitors the wafer's rotation speed. However, due to the geometric positional relationship between the two speed measuring wheels, the drive wheels, and the wafer, it is difficult to ensure that the two drive wheels and the speed measuring wheel make perfect contact with the wafer at the same time to produce a good friction effect. This results in the actual rotation speed of the speed measuring wheel being less than the actual rotation speed of the wafer, causing the "speed measuring wheel speed drop" problem.

[0006] Furthermore, since the speed measuring wheel cannot reflect the actual rotational speed of the wafer, the inaccurate data obtained from monitoring the wafer rotational speed will be fed back to the control system that drives the wafer rotation, which will in turn affect the actual rotational speed of the wafer and thus affect the effect of the roller brush cleaning process in wafer processing. Summary of the Invention

[0007] This invention provides a wafer cleaning apparatus, which aims to at least solve one of the technical problems existing in the prior art.

[0008] A first aspect of the present invention provides a wafer cleaning apparatus, comprising:

[0009] Box;

[0010] Support components are used to vertically support and drive the wafer rotation;

[0011] A roller brush, installed inside the housing, is used to clean the surface of the wafer;

[0012] The speed measuring component is located at the top of the housing to measure the rotational speed of the wafer being brushed by snapping it onto the outer edge of the wafer from above.

[0013] In some embodiments, the speed measuring component includes a speed measuring wheel drive device and a speed measuring wheel; the speed measuring wheel drive device can drive the speed measuring wheel to move longitudinally to move the speed measuring wheel above the wafer to be cleaned; the speed measuring wheel drive device can drive the speed measuring wheel to swing to engage with or move away from the outer edge of the wafer.

[0014] In some embodiments, the speed measuring wheel drive device includes a mounting base, with a first mounting hole and a second mounting hole arranged longitudinally on the top of the mounting base; an outer piston rod is disposed inside the first mounting hole, and an inner piston rod is concentrically disposed in the inner hole of the outer piston rod, with the speed measuring wheel fixed to the end of the inner piston rod; the second mounting hole is disposed adjacent to the first mounting hole, and a push rod is disposed inside it.

[0015] In some embodiments, the mounting base is provided with a piston rod air inlet that communicates with the first mounting hole to allow air to be supplied to the chamber formed by the lower end of the outer piston rod and the first mounting hole, thereby driving the speed measuring wheel to move upward.

[0016] In some embodiments, a cam groove is provided on the outer periphery of the outer piston rod, which includes a linear segment and an arc segment integrally formed; the arc segment extends spirally along the axial direction; a rotary guide pin is provided on the side of the mounting base, which can be engaged with the cam groove to drive the speed measuring wheel to swing during the longitudinal movement of the outer piston rod.

[0017] In some embodiments, a guide groove is provided on the outer periphery of the outer piston rod, which is disposed opposite to the cam groove, and the guide groove is disposed along the length direction of the outer piston rod; an extended guide pin is provided on the side of the mounting base, which can be engaged in the guide groove.

[0018] In some embodiments, the mounting base is provided with a push rod air inlet that communicates with the second mounting hole to allow air to pass through the chamber formed by the lower end of the push rod and the second mounting hole, thereby driving the push rod to move upward.

[0019] In some embodiments, the speed measuring assembly further includes an upper mounting plate and a lower mounting plate, which are arranged in parallel and spaced apart and fixed by a connecting pin gap; a compression spring is provided on the outer periphery of the connecting pin, one end of which abuts against the end of the connecting pin and the other end of which abuts against the bottom surface of the lower mounting plate.

[0020] In some embodiments, the upper mounting plate and the lower mounting plate are connected to the upper end of the inner piston rod, and the upper mounting plate and the lower mounting plate are used to fix the disc of the speed measuring wheel.

[0021] In some embodiments, the speed measuring assembly further includes a buffer spring, one end of which is connected to the top of the inner piston rod and the other end of which is connected to the upper mounting plate.

[0022] The beneficial effects of this invention include:

[0023] a. The speed measuring wheel is located on the top of the housing, which enables the two drive wheels and the speed measuring wheel to clamp the wafer together, so as to generate better friction and driving effect, and avoid the problem of drive and speed measurement failure.

[0024] b. The speed measuring component is driven by air pressure to move and swing the speed measuring wheel longitudinally, which has the advantage of convenient operation;

[0025] c. The speed measurement component adopts a modular design, which can be flexibly applied to occasions where wafer rotation speed needs to be measured during wafer cleaning. Attached Figure Description

[0026] The advantages of the present invention will become clearer and easier to understand through the following detailed description in conjunction with the accompanying drawings, which are merely illustrative and do not limit the scope of protection of the present invention, wherein:

[0027] Figure 1 This is a schematic diagram of a wafer cleaning apparatus provided in an embodiment of the present invention;

[0028] Figure 2 This is a perspective view of a wafer cleaning apparatus provided in an embodiment of the present invention;

[0029] Figure 3 This is a schematic diagram of a speed measuring component provided in an embodiment of the present invention;

[0030] Figure 4 yes Figure 3 Disassembly diagram of components of the speed measuring wheel drive unit;

[0031] Figure 5 This is a schematic diagram of an external piston rod provided in an embodiment of the present invention;

[0032] Figure 6 This is a schematic diagram of the external piston rod from another perspective, provided in an embodiment of the present invention. Detailed Implementation

[0033] The technical solutions of the present invention will be described in detail below with reference to specific embodiments and accompanying drawings. The embodiments described herein are specific implementations of the present invention, used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary, and should not be construed as limiting the implementation methods or the scope of protection of the present invention. In addition to the embodiments described herein, those skilled in the art can employ other obvious technical solutions based on the content disclosed in the claims and specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein.

[0034] The accompanying drawings in this specification are schematic diagrams used to illustrate the concept of the invention and to schematically show the shapes of the various parts and their interrelationships. It should be understood that, in order to clearly show the structure of the various components of the embodiments of the invention, the drawings are not drawn to the same scale, and the same reference numerals are used to indicate the same parts in the drawings.

[0035] In this invention, a wafer (W) is also called a substrate, with the same meaning and practical function. The term "comprising" and similar expressions should be understood as open-ended inclusion, i.e., "including but not limited to". The term "based on" should be understood as "at least partially based on". The term "one embodiment" or "this embodiment" should be understood as "at least one embodiment". The terms "first", "second", etc., may refer to different or the same objects and are used only to distinguish the objects referred to, without implying a specific spatial order, temporal order, order of importance, etc., of the objects referred to. In some embodiments, values, processes, selected items, determined items, devices, apparatuses, means, parts, components, etc., are referred to as "best", "lowest", "highest", "minimum", "maximum", etc. It should be understood that such descriptions are intended to indicate that a selection can be made from a number of available functional options, and that such selection is not necessarily better, lower, higher, smaller, larger, or otherwise preferred than other options in any other respect or in all respects.

[0036] Figure 1 This is a schematic diagram of a wafer cleaning apparatus according to an embodiment of the present invention. The wafer cleaning apparatus includes:

[0037] The enclosure 10 provides a relatively enclosed space for wafer cleaning;

[0038] A support assembly is used to vertically support and drive the wafer to rotate; specifically, the support assembly includes a pair of drive wheels 4, which are disposed in the housing 10 to vertically support the wafer 1; the drive wheels 4 are circumferentially configured with locking grooves, the bottom of which abuts against the outer edge of the wafer to drive the wafer to rotate under the action of friction.

[0039] A roller brush 3 is disposed in the housing 10 for brushing the wafer surface; specifically, there is a pair of roller brushes 3, which are disposed on both sides of the wafer 1; the ends of the roller brushes 3 are equipped with drive motors (not shown) to drive the roller brushes 3 to roll around their axis; at the same time, the interior of the roller brushes 3 is also in communication with the external liquid, so that the roller brushes 3 are in an immersion state and contact brush the contaminants on the wafer surface.

[0040] Meanwhile, the interior of the housing 10 is also equipped with a spray assembly 2 to spray cleaning fluid toward the rotating wafer surface to clean the wafer surface.

[0041] Figure 1 In the embodiment shown, the wafer cleaning apparatus further includes a speed measuring component disposed on the upper part of the housing 10 to engage the outer edge of the wafer 1 from above, thereby measuring the rotational speed of the wafer being cleaned.

[0042] In this invention, the speed measuring component is positioned above the wafer being brushed. This arrangement increases the friction between the drive wheel 4 and the wafer 1, as well as the friction between the speed measuring wheel 5 and the wafer 1, thereby solving the problem of slippage between the drive wheel 4 and the speed measuring wheel 5 and the wafer, and thus improving the cleaning effect of the roller brush.

[0043] Figure 2 yes Figure 1 The perspective view of the wafer cleaning apparatus in this embodiment shows that the speed measuring component includes a speed measuring wheel drive device 36 and a speed measuring wheel 5. The speed measuring wheel drive device 36 can drive the speed measuring wheel 5 to move longitudinally, thereby moving the speed measuring wheel 5 above the wafer to be cleaned. The speed measuring wheel drive device 36 can also drive the speed measuring wheel 5 to swing, thereby engaging or disengaging from the outer edge of the wafer. Specifically, during the wafer cleaning process, the speed measuring wheel 5 engages above the wafer to measure the wafer's rotational speed. After the wafer cleaning is completed, the speed measuring wheel 5 needs to move away from above the wafer to prevent interference with the robotic arm's wafer handling.

[0044] Figure 3 This is a schematic diagram of a speed measuring component provided in an embodiment of the present invention. Figure 4 This is a disassembled diagram of the speed measuring wheel drive device 36.

[0045] The speed measuring wheel drive device 36 includes a mounting base 16, with a first mounting hole 16a and a second mounting hole 16b arranged longitudinally on the top of the mounting base 16; an outer piston rod 24 is arranged inside the first mounting hole 16a, and an inner piston rod 21 is concentrically arranged in the inner hole of the outer piston rod 24, with the speed measuring wheel 5 fixed to the end of the inner piston rod 21; the second mounting hole 16b is arranged adjacent to the first mounting hole 16a, and a push rod 14 is arranged inside it.

[0046] Furthermore, the inner hole of the outer piston rod 24 is connected to the first mounting hole 16a, so that the chamber pressure of the first mounting hole 16a can act on the inner piston rod 21.

[0047] In this invention, the mounting base 16 is provided with a piston rod air inlet 31, which communicates with the first mounting hole 16a to allow air to pass through the chamber formed by the lower end of the outer piston rod 24 and the first mounting hole 16a, so as to drive the speed measuring wheel 5 to move upward.

[0048] The outer periphery of the outer piston rod 24 is provided with a cam groove 33, such as Figure 5 As shown, the cam groove 33 includes a linear segment and an arc segment, which are integrally formed; wherein, the arc segment extends spirally along the axial direction.

[0049] A rotating guide pin 30 is provided on the side of the mounting base 16, which can be engaged inside the cam groove 33 to drive the speed measuring wheel 5 to swing during the longitudinal movement of the outer piston rod 24, so that the speed measuring wheel 5 can engage with or move away from the edge of the wafer.

[0050] Furthermore, a guide groove 34 is provided on the outer peripheral side of the outer piston rod 24, such as... Figure 6 As shown, the guide groove 34 is arranged opposite to the cam groove 33, and the guide groove 34 is arranged along the length direction of the outer piston rod 24; a protruding guide pin 27 is provided on the side of the mounting base 16, which can be engaged in the guide groove 34.

[0051] Figure 4 In the embodiment shown, the mounting base 16 is also provided with a push rod air inlet 32, which communicates with the second mounting hole 16b to allow air to be supplied to the cavity formed by the lower end of the push rod 14 and the second mounting hole 16b, so as to drive the push rod 14 to move upward.

[0052] Furthermore, the speed measuring assembly also includes an upper mounting plate 22 and a lower mounting plate 23, which are arranged parallel to each other and fixed by a gap in the connecting pin 12; that is, a gap is provided between the connecting pin 12 and the fixing holes of the upper mounting plate 22 and the lower mounting plate 23. A compression spring 13 is provided on the outer periphery of the connecting pin 12, one end of the compression spring 13 abuts against the end of the connecting pin 12, and the other end of the compression spring 13 abuts against the bottom surface of the lower mounting plate 23.

[0053] In this invention, the upper mounting plate 22 and the lower mounting plate 23 are connected to the upper end of the inner piston rod 21, and the upper mounting plate 22 and the lower mounting plate 23 are used to fix the disc of the speed measuring wheel 5. Figure 3 The speed measuring wheel 5 is shown to include a left speed measuring wheel 40 and a right speed measuring wheel 41.

[0054] Figure 3 In the process, the speed measuring component also includes a buffer spring 11, one end of which is connected to the top of the inner piston rod 21, and the other end of which is connected to the upper mounting plate 22, so as to play a buffering role and prevent the speed measuring wheel 5 from making hard contact with the wafer and causing the wafer to break.

[0055] In this invention, the push rod 14 can telescopically move within the second mounting hole 16b of the mounting base 16. A push rod compression spring 15 is also disposed around the outer periphery of the push rod 14, with one end contacting the push rod 14 and the other end contacting the lower sealing gasket of the retaining spring. The outer sidewall of the lower sealing gasket abuts against the inner sidewall of the second mounting hole 16b. When the cavity formed by the lower end of the push rod 14 and the second mounting hole 16b is pressurized, the push rod 14 can move longitudinally.

[0056] The mounting base 16 is also equipped with a magnetic switch 17 for monitoring the extension of the push rod and a magnetic switch 18 for monitoring the retraction of the push rod 14.

[0057] The rotary guide pin 30, located on the side of the mounting base 16, is also equipped with a rotary adjustment spring 19 and a rotary adjustment knob 20 to assist in adjusting the installation state of the rotary guide pin 30.

[0058] Meanwhile, the extension guide pin 27 is equipped with an extension adjustment knob 25 and an extension adjustment spring 26 to assist in adjusting the installation state of the extension guide pin 27. The extension guide pin 27 can slide inside the guide groove 34 to limit the vertical movement of the outer piston rod 24.

[0059] Figure 3 In the mounting base 16, there are also magnetic switches 28 for monitoring piston rod extension and 29 for monitoring piston rod retraction, which are used to monitor the piston rod in place.

[0060] The operating steps of the wafer cleaning apparatus provided by this invention are briefly described below, especially the operating steps of the speed measuring component.

[0061] First, the speed measuring component is in its initial state, and the robotic arm places the wafer to be cleaned onto the drive wheel 4 of the support component. Next, compressed air is introduced into the air inlet 31 of the mounting base 16, causing the outer piston rod 24 to extend under air pressure. When the outer piston rod 24 extends to the point where it is tangent to the extension guide pin 27 in the guide groove 34, it encounters resistance and stops moving. In some embodiments, the extension resistance of the outer piston rod 24 can be adjusted by adjusting the extension adjustment knob 25 and the pressure of the compression member extension adjustment spring 26.

[0062] Next, after the outer piston rod 24 stops extending due to resistance, compressed air continues to be injected to apply pressure to the inner piston rod 21. When the pressure is greater than the resistance given to the inner piston rod 21 by the compression tower spring 13, the inner piston rod 21 will extend, and the compression tower spring 13 will be in a compressed state. At this time, the left speed measuring wheel 40 and the right speed measuring wheel 41 of the speed measuring wheel 5 will be opened.

[0063] When the inner piston rod 21 extends to its limit position, compressed air continues to be injected. When the pressure exceeds the resistance of the extension guide pin 27 to the outer piston rod 24, the outer piston rod 24 continues to rotate and extend along the cam groove 33. Finally, after extending to its limit position, the rotation guide pin 30 will enter the positioning groove 35 of the outer piston rod 24. Figure 6 As shown in the diagram, the speed measuring wheel 5 is in contact with the edge of the wafer to serve a positioning function.

[0064] After the speed measuring wheel 5 contacts the edge of the wafer, the air inlet 31 is opened to the atmosphere, and the inner piston rod 21 retracts under the elastic force of the compression tower spring 13. At this time, the left speed measuring wheel 40 and the right speed measuring wheel 41 of the speed measuring wheel 5 close to clamp the edge of the wafer so that the measurement of the wafer rotation speed can begin.

[0065] After the wafer is cleaned, compressed air is introduced into the push rod air inlet 32 ​​of the speed measuring wheel drive device 36, the push rod compression spring 15 is compressed, the push rod 14 extends and causes the compression tower spring 13 to be compressed and shortened. At this time, the speed measuring wheel 5 opens, and then the piston rod air inlet 31 is evacuated to create a vacuum. The inner piston rod 21 and the outer piston rod 24 return to their original positions, the push rod air inlet 32 ​​is opened to the atmosphere, and the push rod 14 is retracted by the elastic force of the push rod compression spring 15, thereby driving the speed measuring wheel 5 to return to its original position along the original displacement path, avoiding the robot arm picking up and placing wafers.

[0066] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A wafer cleaning apparatus, characterized in that, include: Box; Support components are used to vertically support and drive the wafer rotation; A roller brush, installed inside the housing, is used to clean the surface of the wafer; The speed measuring component is located at the top of the housing to measure the rotational speed of the wafer being brushed by snapping it onto the outer edge of the wafer from above. The speed measuring component includes a speed measuring wheel drive device and a speed measuring wheel; The speed measuring wheel drive device includes a mounting base, on the side of which are provided a first mounting hole and a second mounting hole in a longitudinal direction, the longitudinal direction being perpendicular to the wafer surface; an outer piston rod is disposed inside the first mounting hole, and an inner piston rod is concentrically disposed in the inner hole of the outer piston rod; the inner hole of the outer piston rod communicates with the first mounting hole so that the chamber pressure of the first mounting hole can act on the inner piston rod; the second mounting hole is disposed adjacent to the first mounting hole, and a push rod is disposed inside it; The outer piston rod is provided with a cam groove on its outer periphery, which includes a linear section and an arc section, both integrally formed; the arc section extends spirally along the axial direction; a rotating guide pin is provided on the side of the mounting base, which can be engaged with the cam groove to drive the speed measuring wheel to swing during the longitudinal movement of the outer piston rod. The speed measuring assembly also includes an upper mounting plate and a lower mounting plate, which are arranged parallel to each other and fixed by a connecting pin with a gap; a compression spring is provided on the outer periphery of the connecting pin, one end of which abuts against the end of the connecting pin, and the other end of which abuts against the bottom surface of the lower mounting plate; the upper mounting plate and the lower mounting plate are connected to the end of the inner piston rod, and the upper mounting plate and the lower mounting plate are used to fix the disc of the speed measuring wheel; the speed measuring wheel includes a left speed measuring wheel and a right speed measuring wheel.

2. The wafer cleaning apparatus as described in claim 1, characterized in that, The mounting base is equipped with a piston rod air inlet, which communicates with the first mounting hole to allow air to be supplied to the chamber formed by the end of the outer piston rod and the first mounting hole, so as to drive the speed measuring wheel to move away from the mounting base along the axis of the outer piston rod.

3. The wafer cleaning apparatus as described in claim 1, characterized in that, The outer piston rod has a guide groove on its outer periphery, which is opposite to the cam groove, and the guide groove is arranged along the length of the outer piston rod; the mounting base has an extended guide pin on its side, which can be engaged in the guide groove.

4. The wafer cleaning apparatus as described in claim 3, characterized in that, The extension guide pin is equipped with an extension adjustment knob and an extension adjustment spring to adjust the extension resistance of the extension guide pin to the outer piston rod.

5. The wafer cleaning apparatus as described in claim 1, characterized in that, The mounting base is equipped with a push rod air inlet, which communicates with the second mounting hole to allow air to pass through the cavity formed by the end of the push rod and the second mounting hole, so as to drive the push rod to move longitudinally.

6. The wafer cleaning apparatus as described in claim 5, characterized in that, A push rod compression spring is disposed on the outer periphery of the push rod, one end of which contacts the push rod and the other end of which contacts the lower sealing gasket of the snap ring. The outer side wall of the lower sealing gasket of the snap ring abuts against the inner side wall of the second mounting hole. When the cavity formed by the end of the push rod and the second mounting hole is depressurized, the push rod can retract under the elastic force of the push rod compression spring.

7. The wafer cleaning apparatus as described in claim 1, characterized in that, The outer piston rod is provided with a positioning groove. After the outer piston rod extends to its limit position, the rotary guide pin can enter the positioning groove to position the outer piston rod.

8. The wafer cleaning apparatus as described in claim 1, characterized in that, The rotary guide pin is equipped with a rotary adjustment spring and a rotary adjustment knob to assist in adjusting the installation state of the rotary guide pin.

9. The wafer cleaning apparatus as described in claim 1, characterized in that, The speed measuring component also includes a buffer spring, one end of which is connected to the end of the inner piston rod, and the other end of which is connected to the upper mounting plate.

10. The wafer cleaning apparatus as described in claim 1, characterized in that, The mounting base is equipped with a magnetic switch for monitoring the extension of the push rod and a magnetic switch for monitoring the retraction of the push rod, used for monitoring the push rod's position; the mounting base is also equipped with a magnetic switch for monitoring the extension of the piston rod and a magnetic switch for monitoring the retraction of the piston rod, used for monitoring the piston rod's position.

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