Wafer cleaning device and method

Abstract

The embodiment of the present application provides a wafer cleaning device and method, the cleaning device includes a cleaning mechanism and a fixing mechanism; the fixing mechanism includes a support structure, a limit ring, a slider and a first preset number of clamps; the limit ring is rotatably connected to the support structure; the slider is arranged on the inner side of the limit ring, the number of sliders matches the clamps, and the slider and the clamps are arranged at intervals; the first preset number of clamps are movably connected to the support structure, and the first preset clamps are embedded in the inner side of the limit ring; the cleaning mechanism is arranged at the bottom of the wafer to be cleaned. During the wafer cleaning process, the cleaning device drives the slider to rotate through the limit ring, and then drives the clamp to extend and retract, so that it clamps the chamfered edge of the wafer, thereby fixing the wafer, and then using the cleaning mechanism to clean the bottom of the wafer, which not only improves the cleaning efficiency, but also reduces the loss caused by wafer damage and improves the yield of the wafer.

Description

Technical Field

[0001] The present application relates to the field of semiconductor equipment, and in particular to a wafer cleaning device and method. Background Art

[0002] In the chip production process, wafers are repeatedly transferred between modules, and large particles are bound to adhere to the back of the wafers. In photolithography equipment, the wafer surface height is very sensitive, and particles of a few tenths of a micron on the back will cause the wafer surface height to be uneven, thus causing defects in the morphology and line width of the replica pattern.

[0003] In the semiconductor industry, all wafer wet processing equipment needs to ensure its own cleanliness, that is, the number of microparticles on the surface of the wafer to be processed cannot be increased. At the same time, some special processes require the back of the wafer to be cleaned. However, the existing technology has the problem of long cleaning time and instability. During the high-speed spin-drying process, the wafer is easily thrown out, causing damage to the wafer and the cleaning mechanism. When cleaning the edge of the wafer, it is easy to cause water droplets to drip and liquid to accumulate in the vacuum line of the vacuum suction cup, resulting in a decrease in adsorption force when the wafer is adsorbed, resulting in low cleaning effect and cleaning efficiency. Therefore, there is an urgent need for an improved wafer cleaning device. Summary of the invention

[0004] In order to solve the above technical problems, the present application proposes a wafer cleaning device and method.

[0005] On the one hand, an embodiment of the present application provides a wafer cleaning device, comprising: a cleaning mechanism and a fixing mechanism;

[0006] The fixing mechanism comprises a supporting structure, a limiting ring, a slider and a first preset number of clamps; the limiting ring is rotatably connected to the supporting structure; the slider is arranged on the inner side of the limiting ring, the number of the sliders matches the clamps, and the sliders and the clamps are arranged at intervals; the first preset number of clamps are movably connected to the supporting structure, and the first preset number of clamps are embedded in the inner side of the limiting ring;

[0007] A cleaning mechanism is arranged at the bottom of the wafer to be cleaned;

[0008] The limiting ring is used to drive the slider to rotate on the supporting structure under the drive of external force, so as to drive a first preset number of clamps to move toward the center of the limiting ring, thereby fixing the wafer to be cleaned, and then using the cleaning mechanism to clean the bottom of the wafer to be cleaned.

[0009] Further, the clamp comprises a clamp head and a clamp body, and the clamp head and the clamp body are fixedly connected;

[0010] The thickness of the chuck is 4mm-6mm and the width is 50mm-60mm;

[0011] The thickness of the fixture body is 3mm-5mm, the length is 40mm-50mm, and the width is 50mm-60mm;

[0012] The material of the fixture body includes hard ceramics, and the material of the chuck includes semiconductor ceramics.

[0013] Further, the angles between two adjacent clamps are equal;

[0014] The first preset number is greater than or equal to 4.

[0015] Furthermore, the wafer cleaning device also includes a driving mechanism, which is arranged outside the limiting ring and connected to the limiting ring for driving the limiting ring to rotate.

[0016] Further, the cleaning mechanism includes a cleaning brush plate and a base;

[0017] The cleaning brush plate is circular, and the edge of the cleaning brush plate is tangent to the bottom edge of the wafer to be cleaned;

[0018] The base is movably connected to the cleaning brush disc, and the base is arranged at the center of a circle at the bottom of the cleaning brush disc.

[0019] Furthermore, the difference between the diameter of the cleaning brush plate and the radius of the wafer to be cleaned is greater than or equal to 10 mm, so that the cleaning brush plate can cover the center of the wafer to be cleaned;

[0020] The thickness of the cleaning brush plate is 40mm-50mm;

[0021] The material of the cleaning brush plate includes absorbent cotton.

[0022] Furthermore, a second preset number of parallel cleaning sheets are fixedly arranged on the surface of the cleaning brush disc, and the distance between adjacent cleaning sheets is 10 mm-20 mm;

[0023] Among the second preset number of parallel cleaning sheets, each cleaning sheet has a width of 4 mm to 6 mm and a raised edge height of 0.1 mm to 0.3 mm;

[0024] The material of the cleaning sheet includes a hard plastic sheet.

[0025] Furthermore, at least one ultrapure water nozzle is provided in the base for soaking and cleaning the brush plate, and the flow rate of the ultrapure water nozzle is 100-200 ml / min.

[0026] Furthermore, a rotating mechanism is also provided in the base, which is used to drive the cleaning brush disc to rotate and clean along the bottom edge of the wafer to be cleaned, and to drive the cleaning brush disc to rotate during the cleaning process;

[0027] Among them, the rotation speed of rotary cleaning is 40r / min-100r / min, and the rotation speed is 4r / min-10r / min.

[0028] Furthermore, a nitrogen drying mechanism is provided on at least one side of the bottom of the limiting ring for drying the cleaned wafer;

[0029] The drying nitrogen flow rate is 1200ml / min-1500ml / min, and the drying temperature is 40℃-50℃.

[0030] On the other hand, an embodiment of the present application further provides a wafer cleaning method, which is implemented by the above-mentioned wafer cleaning device, and the method includes:

[0031] Transferring the wafer to be cleaned to the limiting ring, and controlling the center of the wafer to be cleaned to overlap with the center of the limiting ring;

[0032] The limiting ring is driven by external force to drive the slider to rotate, so that the slider drives a first preset number of clamps to move toward the center of the limiting ring and fix the wafer to be cleaned;

[0033] The bottom of the wafer to be cleaned is cleaned by the cleaning mechanism to obtain a cleaned wafer.

[0034] Furthermore, the wafer cleaning device includes a rotating mechanism, the cleaning mechanism includes a cleaning brush plate and a base, and the base is provided with at least one ultrapure water nozzle and a rotating mechanism; the bottom of the wafer to be cleaned is cleaned by the cleaning mechanism to obtain a cleaned wafer, including:

[0035] The brush plate is continuously wetted and cleaned by the ultrapure water nozzle; during the cleaning process, the flow rate of the ultrapure water nozzle is 100ml / min-200ml / min;

[0036] The cleaning brush is driven by a rotating mechanism to rotate and clean along the back edge of the wafer to be cleaned, and the cleaning brush is driven to rotate during the cleaning process until the bottom of the wafer to be cleaned is cleaned; wherein, the rotation speed of the rotary cleaning is 40r / min-100r / min, and the rotation speed is 4r / min-10r / min.

[0037] On the other hand, an embodiment of the present application also provides a glue coating device, including the above-mentioned wafer cleaning device.

[0038] Compared with the prior art, the wafer cleaning device provided in the embodiment of the present application has at least the following technical effects:

[0039] 1. The fixing mechanism provided in the embodiment of the present application clamps the chamfered area of ​​the wafer under the drive of the slider through the clamp, thereby achieving wafer fixation. This fixing method not only improves the stability of wafer fixation, but also improves the convenience and flexibility of fixation.

[0040] 2. The fixing mechanism provided in the embodiment of the present application ensures that the wafer is fixed during the cleaning process, avoiding the risk of the wafer being thrown out during high-speed rotary cleaning or high-speed rotary drying, thereby improving the yield of wafer cleaning and reducing the time cost and equipment maintenance cost caused by the risk of fragments caused by the wafer being thrown out. In this way, the clamp is set at the edge of the wafer, and the cleaning mechanism is set at the bottom of the wafer, which can reduce the interference of the fixing mechanism with the cleaning mechanism.

[0041] 3. The fixing device provided in the embodiment of the present application does not contact the surface of the wafer, thereby avoiding the problem of cumbersome cleaning process and long cleaning time caused by fixing the wafer with a suction cup in the prior art, optimizing the cleaning steps and improving the cleaning efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present application or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0043] Figure 1 The figure is a side view of a conventional wafer backside cleaning device;

[0044] Figure 2 The present invention is a structural schematic diagram of an existing wafer backside cleaning device during operation;

[0045] Figure 3 Another structural schematic diagram of an existing wafer backside cleaning device during operation;

[0046] Figure 4 It is a structural schematic diagram of a wafer cleaning device provided in an embodiment of the present application;

[0047] Figure 5 is a side view of a wafer cleaning device provided in an embodiment of the present application;

[0048] Figure 6 It is a structural schematic diagram of a fixing mechanism in a wafer cleaning device provided in an embodiment of the present application;

[0049] Figure 7It is a structural schematic diagram of a fixture in a wafer cleaning device provided in an embodiment of the present application;

[0050] Figure 8 It is a structural schematic diagram of a cleaning brush disc in a wafer cleaning device provided in an embodiment of the present application;

[0051] Fig. 9 It is a flow chart of a wafer cleaning method provided in an embodiment of the present application.

[0052] Wherein, the accompanying drawings are marked as follows:

[0053] 1-fixing mechanism; 11-supporting structure; 12-limiting ring; 13-slider; 14-clamp; 141-clamp body; 142-chuck;

[0054] 2-cleaning mechanism; 21-cleaning brush plate; 211-cleaning sheet; 22-base; 221-ultrapure water nozzle;

[0055] 3- Driving mechanism;

[0056] 4-Nitrogen drying mechanism. DETAILED DESCRIPTION

[0057] In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein should be understood by people with general skills in the field to which the present invention belongs. "Including" and similar words used in this article mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0058] In the chip production process, the wafers are repeatedly transferred between various modules, and it is inevitable that large particles will adhere to the back of the wafers. In the photolithography equipment, the surface height of the wafer is very sensitive. Particles of a few tenths of a micron on the back will cause the surface height of the wafer to be uneven, thus causing defects in the morphology and line width of the replica pattern. Therefore, before the wafer enters the photolithography equipment, the glue coating equipment has a mechanism BST (Back Surface Treatment) that cleans the back of the wafer.

[0059] In the prior art, such as Figure 1-Figure 3As shown, BST usually includes a circular brush head, a central suction cup, four edge suction cups, multiple ultrapure water nozzles, and nitrogen blowing nozzles. The cleaning process is: first, the vacuum suction cup is used to suck the center of the back of the wafer and keep rotating, while the brush head rotates and swings back and forth to spray water to brush the back edge. Then the four edge suction cups suck the wafer and move it to the central brushing area to remove impurities in the center. Finally, it is blown dry with nitrogen and sent out. However, this cleaning mechanism has the following disadvantages:

[0060] 1. When cleaning the edge of the wafer, the four edge suction cups are waiting under the wafer, and water droplets will inevitably fall into them. In addition, in a humid environment for a long time, a certain amount of liquid will accumulate in the vacuum suction line of the vacuum suction cup, resulting in a decrease in the adsorption force when adsorbing the wafer, triggering the equipment alarm. This type of alarm requires manual removal of the wafer. When the wafer is exposed, there is a high risk of scrapping, and the machine needs to be shut down to clean the vacuum line.

[0061] 2. This type of cleaning mechanism will have a high-speed rotation and drying action at the end of the process. However, the diameter of the central suction cup of this mechanism is small. In a humid environment for a long time, the surface humidity of the suction cup is too high, and there are cases where the wafer is thrown out during high-speed drying. Not only will the mechanism be damaged, but the debris is also time-consuming and laborious to clean up.

[0062] 3. The cleaning process is cumbersome, long and unstable.

[0063] Based on this, the present application embodiment proposes a wafer cleaning device, such as Figure 4 As shown, the wafer cleaning device includes a cleaning mechanism 2 and a fixing mechanism 1; the fixing mechanism 1 includes a supporting structure 11, a limiting ring 12, a slider 13 and a first preset number of clamps 14; the limiting ring 12 is rotatably connected to the supporting structure 11; the slider 13 is arranged on the inner side of the limiting ring 12, the number of sliders 13 matches the clamp 14, and the slider 13 and the clamp 14 are arranged at intervals; the first preset number of clamps 14 are movably connected to the supporting structure 11, and the first preset number of clamps 14 are embedded in the inner side of the limiting ring 12; the cleaning mechanism 2 is arranged at the bottom of the wafer to be cleaned; the limiting ring 12 is used to drive the slider 13 to rotate on the supporting structure 11 under the drive of external force, so as to drive the first preset number of clamps 14 to move toward the center of the limiting ring 12, thereby fixing the wafer to be cleaned, and then using the cleaning mechanism 2 to clean the bottom of the wafer to be cleaned.

[0064] For example, see Figure 4-Figure 6 The cleaning device provided in the embodiment of the present application includes two main parts, a cleaning mechanism 2 and a fixing mechanism 1.

[0065] Specifically, Figure 5 and Figure 6As shown, the fixed structure includes a support structure 11, a limiting ring 12, a slider 13 and a first preset number of clamps 14; wherein the limiting ring 12 is rotatably connected to the support structure 11, the slider 13 is arranged on the inner side of the limiting ring 12 and is fixedly connected to the limiting ring 12 so as to be rotatable with the limiting ring 12; the first preset number of clamps 14 are arranged on the inner side of the support structure 11 and are movably connected to the support structure 11, and the first preset number of clamps 14 are embedded in the limiting ring 12. The limiting ring 12 is a central circle with an opening, and its function is to drive the slider 13 to rotate under the drive of an external force, and the support structure 11 is wrapped in the limiting ring 12.

[0066] The first preset number of clamps 14 will move toward the center of the circle or toward the limit ring 12 under the drive of the slider 13. Specifically, before the wafer cleaning starts, the limit ring 12 drives the slider 13 to rotate in the first preset direction under the drive of an external force, so that the slider 13 is close to the clamp 14 and moves between the clamp 14 and the support structure 11, so that the clamp 14 moves toward the center of the circle and clamps the chamfer of the wafer edge to fix the wafer to be cleaned; when the wafer cleaning is completed, the limit ring 12 drives the slider 13 to rotate in the second preset direction under the drive of an external force, so that the slider 13 is away from the clamp 14, and the clamp 14 moves toward the limit ring 12 to release the cleaned wafer so that it can be transferred to the next working area by the robot. The above-mentioned first preset direction can be clockwise or counterclockwise, as long as the first preset direction and the second preset direction are opposite.

[0067] In order to ensure that each of the first preset number of clamps 14 is driven to move to a target position when fixing the wafer, the number of sliders 13 matches the number of clamps 14 , and the sliders 13 and the clamps 14 are arranged at intervals.

[0068] After the wafer to be cleaned is fixed by the clamp 14, the cleaning mechanism 2 located at the bottom of the wafer to be cleaned starts to clean the bottom of the wafer. Generally, the bottom of the wafer refers to the back side of the wafer. When used in specific circumstances, it can also be the front side of the wafer.

[0069] This device can be used as glue coating equipment in semiconductor processes. Before glue coating is completed and entering photolithography, this device is used to clean the back of the wafer.

[0070] Optionally, when the cleaning mechanism 2 is designed for a 12-inch device and is designed to perform wafer fixing operations, the sliding height is 30 mm-40 mm, that is, the slider 13 can drive the clamp 14 to move 30 mm-40 mm toward the center of the circle.

[0071] It should be noted that the height and width of the slider 13, and the radius of the limiting ring 12 and the supporting structure 11 are determined according to the size of the wafer that actually needs to be cleaned.

[0072] In the embodiment of the present application, during the cleaning process of the wafer, the cleaning device drives the slider 13 to rotate through the limit ring 12, and then drives the clamp 14 to extend and retract, so that it clamps the chamfer of the wafer edge, thereby achieving wafer fixation. This fixing method not only improves the stability of wafer fixation, but also improves the convenience and flexibility of fixation. It also ensures that the wafer is fixed during the cleaning process, avoiding the risk of the wafer being thrown out during high-speed rotation cleaning or high-speed rotation drying, which not only improves the yield of wafer cleaning, but also reduces the time cost and equipment maintenance cost caused by the risk of fragments caused by the wafer being thrown out; and in this way, the clamp 14 is set at the edge of the wafer, and the cleaning mechanism 2 is set at the bottom of the wafer, which can reduce the interference of the fixing mechanism 1 with the cleaning mechanism 2. And the fixing device does not contact the surface of the wafer, so as to avoid the problem of cumbersome cleaning process and long cleaning time caused by fixing the wafer with a suction cup in the prior art, optimize the cleaning steps, and improve the cleaning efficiency.

[0073] In an optional embodiment, the clamp 14 includes a chuck 142 and a clamp 14 body, and the chuck 142 and the clamp 14 body are fixedly connected; the thickness of the chuck 142 is 4mm-6mm, and the width is 50mm-60mm; the thickness of the clamp 14 body is 3mm-5mm, the length is 40mm-50mm, and the width is 50mm-60mm; the material of the clamp 14 body includes hard ceramics, and the material of the chuck 142 includes semiconductor ceramics.

[0074] For example, Figure 7 As shown, the clamp 14 consists of two parts: a clamp head 142 and a clamp body 14 . The clamp head 142 and the clamp body 14 are fixedly connected, and the clamp body 14 and the support structure 11 are movably connected. The clamp head 142 is used to clamp the wafer to be cleaned.

[0075] Specifically, the thickness of the clamp 142 is 4 mm-6 mm, and the width is 50 mm-60 mm; the thickness of the main body of the clamp 14 is 3 mm-5 mm, the length is 40 mm-50 mm, and the width is 50 mm-60 mm.

[0076] The material of the main body of the clamp 14 includes hard ceramics, which have the characteristics of good rigidity and no deformation, and can ensure that it is not easily worn during use. The material of the chuck 142 includes semiconductor ceramics, which have the characteristics of anti-static and good rigidity, and can effectively release accumulated static electricity, thereby protecting the wafer from static electricity damage. When clamping the wafer, the chuck 142 will not be deformed due to external force, thereby ensuring the precise positioning and stability of the wafer during the processing process.

[0077] Optionally, the length of the chuck 142 is designed according to the applied machine. For example, when it is applied to a 12-inch machine, the edge chamfer area of ​​the wafer is 3 mm wide, so the length of the chuck 142 is designed to be 3 mm, preferably 3 mm.

[0078] Optionally, the main body of the clamp 14 and the supporting structure 11 are movably connected via a connecting piece, and the connecting piece may be an elastic piece or a retractable connecting piece; the connecting piece may be built into the main body of the clamp 14 or may be arranged outside the main body of the clamp 14.

[0079] It should be noted that the material of the clamp body 141 and the material of the clamp head 142 can also be other types as long as the same technical effect is achieved.

[0080] The embodiment of the present application limits the specific structure and size of the clamp 14 so that it can better achieve the fixing function, which can prevent the clamp 14 from deforming during use and causing a decrease in wafer yield, thereby improving the stability of the fixing mechanism 1 during the cleaning process and improving the wafer cleaning yield.

[0081] In an optional implementation, the angles between two adjacent clamps 14 are equal; and the first preset number is greater than or equal to 4.

[0082] Exemplarily, in order to ensure uniformity of the clamping force on the wafer in all directions, the number of clamps 14 is greater than or equal to 4, and the angles between every two adjacent clamps 14 are equal.

[0083] Optionally, in order to achieve cost reduction and ensure uniform force on the wafers during the cleaning process, the number of clamps 14 is set to 4, with the angle between every two clamps 14 being 90°.

[0084] The embodiment of the present application limits the number of clamps 14 and the angles between adjacent clamps 14 to ensure uniform force on the wafer during the cleaning process, thereby further ensuring the stability of wafer fixation and ensuring that the wafer is fixed during the cleaning process, thereby avoiding the risk of the wafer being thrown out during high-speed rotary cleaning or high-speed rotary drying, thereby improving the yield of wafer cleaning and reducing the time cost and equipment maintenance cost caused by the risk of fragments caused by wafer being thrown out; and in this way, the clamps 14 are arranged at the edge of the wafer, and the cleaning mechanism 2 is arranged at the bottom of the wafer, which can reduce the interference of the fixing mechanism 1 with the cleaning mechanism 2.

[0085] In an optional embodiment, the wafer cleaning device further includes a driving mechanism 3 , which is disposed outside the limiting ring 12 and connected to the limiting ring 12 for driving the limiting ring 12 to rotate.

[0086] For example, Figure 4As shown, a driving mechanism 3 is arranged on the outer side of the limit ring 12, and the driving mechanism 3 and the limit ring 12 are rotatably connected; the driving mechanism 3 is used to drive the limit ring 12 to rotate, so that the limit ring 12 can be used to drive the slider 13 to rotate, thereby realizing the extension and retraction of the clamp 14, and the extension and retraction of the clamp 14 refers to its movement toward the center of the circle, or toward the limit ring 12.

[0087] Optionally, the driving mechanism 3 may be a gear driven by a motor.

[0088] The embodiment of the present application realizes the rotation of the limit ring 12 through the driving mechanism 3, so that the limit ring 12 can be used to drive the slider 13 to rotate, and then the clamp 14 can be extended and retracted, thereby ensuring the flexibility and convenience of fixing the wafer edge with the clamp 14.

[0089] As an optional embodiment, the cleaning mechanism 2 includes a cleaning brush disc 21 and a base 22; the cleaning brush disc 21 is circular, and the edge of the cleaning brush disc 21 is tangent to the bottom edge of the wafer to be cleaned; the base 22 is movably connected to the cleaning brush disc 21, and the base 22 is arranged at the center of the bottom of the cleaning brush disc 21.

[0090] For example, Figure 5 As shown, the cleaning structure includes two parts, a cleaning brush plate 21 and a base 22. The cleaning brush plate 21 is used to brush the bottom of the wafer. In order to ensure the efficiency of brushing and brushing without dead angles, the edge of the cleaning brush plate 21 is set to be tangent to the back edge of the wafer to be cleaned.

[0091] The base 22 is used to support the cleaning brush disc 21 and to install the related supporting facilities of the cleaning brush disc 21. The top of the base 22 is movably connected to the cleaning brush disc 21, which ensures that the cleaning brush disc 21 can be disassembled, maintained and replaced. The base 22 is set at the center of the bottom of the cleaning brush disc 21 to ensure the balance of the cleaning brush disc 21.

[0092] As an optional embodiment, the difference between the diameter of the cleaning brush disc 21 and the radius of the wafer to be cleaned is greater than or equal to 10 mm, so that the cleaning brush disc 21 can cover the center of the wafer to be cleaned; the thickness of the cleaning brush disc 21 is 40mm-50mm; the material of the cleaning brush disc 21 includes absorbent cotton.

[0093] For example, Figure 4 As shown, in order to improve the cleaning efficiency and clean the entire wafer at one time, the difference between the diameter of the cleaning brush plate 21 and the radius of the wafer to be cleaned is greater than or equal to 10 mm, so that the cleaning brush plate 21 can cover the center of the wafer to be cleaned.

[0094] The material of the cleaning brush plate 21 can be washed cotton, because washed cotton has the advantages of being soft, washable and durable, not easy to lose fibers, good tensile strength, high density, etc., and will not cause damage to the wafer surface. In order to further ensure the cleaning effect, ultra-fine washed cotton can be selected.

[0095] As an optional embodiment, a rotating mechanism is also provided in the base 22, which is used to drive the cleaning brush disc 21 to rotate and clean along the back edge of the wafer to be cleaned, and to drive the cleaning brush disc 21 to rotate during the cleaning process; wherein the rotation speed of the rotation cleaning is 40r / min-100r / min, and the rotation speed is 4r / min-10r / min.

[0096] Exemplarily, the cleaning process of the bottom of the wafer is as follows: the cleaning brush disc 21 rotates and cleans along the bottom edge of the wafer to be cleaned, thereby achieving a one-time cleaning of the bottom of the wafer. Therefore, a rotating mechanism (not shown in the figure) is provided in the base 22 to drive the cleaning brush disc 21 to rotate and clean along the back edge of the wafer to be cleaned.

[0097] Furthermore, in order to improve the cleaning effect, the rotating mechanism also drives the cleaning brush disc 21 to rotate during the cleaning process.

[0098] In order to ensure the cleaning effect, the rotation speed of the rotary cleaning is 40r / min-100r / min, and the rotation speed is 4r / min-10r / min.

[0099] Optionally, the optimal rotation speed for rotary cleaning is 60r / min, and the rotation speed is 6r / min.

[0100] As an optional implementation, at least one ultrapure water nozzle 221 is further provided in the base 22 for soaking and cleaning the brush plate 21 , and the flow rate of the ultrapure water nozzle 221 is 100-200 ml / min.

[0101] Exemplarily, at least one ultrapure water nozzle 221 is provided at the center of the base 22, with the nozzle opening facing the cleaning brush plate 21, for wetting the cleaning brush plate 21. During the cleaning process, the ultrapure water nozzle 221 continuously sprays water at a flow rate of 100-200 ml / min.

[0102] Optionally, in order to reduce costs, only one ultrapure water nozzle 221 may be provided, and the flow rate may be set to 150 ml / min.

[0103] The embodiment of the present application defines that the cleaning mechanism 2 includes a base 22 and a cleaning brush plate 21, and defines the size and material of the cleaning brush plate 21. The cleaning water source of the cleaning brush plate 21 is set to be an ultrapure water nozzle 221 set at the bottom for continuous infiltration, and the cleaning brush plate 21 is driven by a rotating mechanism to rotate and clean along the bottom edge of the wafer, and rotates during rotational cleaning. By using the cleaning mechanism 2, the entire wafer can be cleaned at one time without dead corners, the cleaning steps are optimized, and the cleaning efficiency is improved.

[0104] As an optional embodiment, a second preset number of parallel cleaning sheets 211 are fixedly provided on the surface of the cleaning brush plate 21, and the distance between adjacent cleaning sheets 211 is 10mm-20mm; among the second preset number of parallel cleaning sheets 211, the width of each cleaning sheet is 4mm-6mm, and the height of the raised edge is 0.1mm-0.3mm; the material of the cleaning sheet includes a hard plastic sheet.

[0105] For example, Figure 8 As shown, a second preset number of parallel cleaning sheets 211 are arranged on the surface of the cleaning brush plate 21, and the distance between adjacent cleaning sheets 211 is 10mm-20mm, which is used to remove pollutants and particles adhering to the back of the wafer during the cleaning process. Specifically, the width of each cleaning sheet is 4mm-6mm, the height of the raised edge is 0.1mm-0.3mm, and the material of the cleaning sheet includes a hard plastic sheet.

[0106] Optionally, the second preset number is determined according to the area of ​​the cleaning brush disc, and the lengths of the cleaning sheets may be the same or different, as long as the cleaning sheets are evenly distributed at a distance of 10 mm to 20 mm on the entire cleaning brush disc.

[0107] Optionally, in order to balance cost and cleaning effect, a better implementation method may be that the distance between adjacent cleaning sheets 211 is 20 mm, the length spans the brush surface, the width of each cleaning sheet is 5 mm, and the height of the raised edge is 0.2 mm.

[0108] The embodiment of the present application arranges parallel cleaning sheets 211 on the surface of the cleaning brush plate 21, so that pollutants and particulate matter adhering to the back side of the wafer can be removed during the cleaning process, thereby further improving the cleaning effect and cleaning efficiency of the cleaning device, avoiding rework caused by unclean cleaning, and saving time costs.

[0109] As an optional embodiment, a nitrogen drying mechanism 4 is provided on at least one side of the bottom of the limiting ring 12 for drying the cleaned wafers; wherein the drying nitrogen flow rate is 1200ml / min-1500ml / min, and the drying temperature is 40℃-50℃.

[0110] For example, Figure 4 As shown, the wafer cleaning device also includes a nitrogen drying mechanism 4, which is arranged on at least one side of the bottom of the limiting ring 12, and is used to dry the cleaned wafers. The drying nitrogen flow rate is 1200ml / min-1500ml / min, and the drying temperature is 40℃-50℃.

[0111] It should be noted that the number and position of the nitrogen drying mechanism 4 are set according to actual needs, and at least one is set. If uniform drying or shortening of drying time is desired, multiple nitrogen drying mechanisms can be set.

[0112] The embodiment of the present application arranges at least one nitrogen drying device at the bottom of the limit ring 12, and the wafer does not need to be rotated during the drying process, thereby avoiding the risk of the wafer being thrown out during high-speed rotation drying, and reducing the time cost and equipment maintenance cost caused by the risk of fragments caused by the wafer being thrown out.

[0113] On the other hand, Fig. 9 As shown, the embodiment of the present application also provides a wafer cleaning method, which is implemented by the above-mentioned wafer cleaning device. The wafer cleaning method includes:

[0114] S10: transferring the wafer to be cleaned into the limiting ring 12 , and controlling the center of the wafer to be cleaned to overlap with the center of the limiting ring 12 .

[0115] Exemplarily, the wafer to be cleaned is transferred to the center of the limiting ring 12 by a robot. In order to achieve uniform force on the wafer, the center of the wafer to be cleaned is controlled to overlap with the center of the limiting ring 12.

[0116] S30: driving the limiting ring 12 to rotate the slider 13 by external force, so that the slider 13 drives a first preset number of clamps 14 to move toward the center of the limiting ring 12 and fix the wafer to be cleaned.

[0117] Illustratively, under the drive of the driving mechanism 3, the limit ring 12 drives the slider 13 to rotate in a first preset direction, so that the slider 13 moves between the clamp 14 and the support structure 11, so that the first preset number of clamps 14 move toward the center of the limit ring 12, thereby fixing the wafer to be cleaned.

[0118] S50: The cleaning mechanism 2 cleans the bottom of the wafer to be cleaned to obtain a cleaned wafer.

[0119] Exemplarily, when the fixture 14 has finished fixing the wafer to be cleaned, the robot arm withdraws, and the cleaning mechanism 2 starts to clean the bottom of the wafer to be cleaned, that is, cleans the back side of the wafer to obtain a cleaned wafer.

[0120] After cleaning, the wafer is dried using a nitrogen drying mechanism 4, the drying nitrogen flow rate is 1200ml / min-1500ml / min, and the drying temperature is 40°C-50°C.

[0121] After drying is completed, the robot re-enters and fixes the wafer. Under the drive of the driving mechanism 3, the limit ring 12 drives the slider 13 to rotate in the second preset direction, so that the first preset number of clamps 14 simultaneously release the cleaned wafers, and the robot transfers the cleaned wafers.

[0122] The first preset direction and the second preset direction are opposite.

[0123] The embodiment of the present application transfers the wafer to be cleaned into the limiting ring 12, and controls the center of the wafer to be cleaned to overlap with the center of the limiting ring 12; drives the limiting ring 12 to rotate by external force and drives the slider 13 to rotate, so that the slider 13 drives the first preset number of clamps 14 to move toward the center of the limiting ring 12 and fix the wafer to be cleaned; cleans the bottom of the wafer to be cleaned by the cleaning mechanism 2, and completes the cleaning step of the bottom of the wafer. This method not only improves the stability of wafer fixation, but also improves the convenience and flexibility of fixation. It also ensures that the wafer is fixed during the cleaning process, avoiding the risk of the wafer being thrown out during high-speed rotation cleaning or high-speed rotation drying, which not only improves the yield of wafer cleaning, but also reduces the time cost and equipment maintenance cost caused by the risk of fragments caused by the wafer being thrown out; and in this way, the clamp 14 is set at the edge of the wafer, and the cleaning mechanism 2 is set at the bottom of the wafer, which can reduce the interference of the cleaning mechanism 2 on the fixing mechanism 1. Furthermore, the fixing device does not contact the surface of the wafer, thereby avoiding the problems of complicated cleaning process and long cleaning time caused by fixing the wafer with a suction cup in the prior art, optimizing the cleaning steps and improving the cleaning efficiency.

[0124] In an optional embodiment, the wafer cleaning device includes a rotating mechanism, the cleaning mechanism 2 includes a cleaning brush plate 21 and a base 22, and the base 22 is provided with at least one ultrapure water nozzle 221 and a rotating mechanism; in the above step S50, the bottom of the wafer to be cleaned is cleaned by the cleaning mechanism 2 to obtain a cleaned wafer, including:

[0125] S51: The brush plate 21 is continuously wetted and cleaned through the ultrapure water nozzle 221; during the cleaning process, the flow rate of the ultrapure water nozzle 221 is 100 ml / min-200 ml / min.

[0126] S52: The cleaning brush disc 21 is driven by a rotating mechanism to rotate and clean along the back edge of the wafer to be cleaned, and the cleaning brush disc 21 is driven to rotate during the cleaning process until the cleaning of the wafer to be cleaned is completed; wherein, the rotation speed of the rotary cleaning is 40r / min-100r / min, and the rotation speed is 4r / min-10r / min.

[0127] Exemplarily, during the cleaning process, the cleaning brush plate 21 is continuously wetted by the ultrapure water nozzle 221 , and the flow rate of the ultrapure water nozzle 221 is 100 ml / min-200 ml / min.

[0128] The cleaning brush disc 21 is driven by a rotating mechanism to rotate and clean along the back edge of the wafer to be cleaned, and the cleaning brush disc 21 is driven to rotate during the cleaning process until the entire back side or the entire bottom of the wafer to be cleaned is cleaned. During the cleaning process, the cleaning sheet on the cleaning sheet can remove particles and other contaminants on the bottom of the wafer, thereby further improving the cleaning efficiency.

[0129] In addition, the embodiment of the present application controls the difference between the diameter of the cleaning brush disc 21 and the radius of the wafer to be cleaned to be greater than or equal to 10 mm, which ensures that the cleaning brush disc completes the cleaning of the entire wafer bottom after one rotation.

[0130] It should be noted that in order to ensure that the cleaning brush does not damage the wafer, the ultrapure water should be completely soaked in the cleaning brush before starting the rotation cleaning.

[0131] The embodiment of the present application soaks an ultra-cleaning brush disc with ultra-pure water, and controls the cleaning brush disc to rotate and clean along the edge of the back side of the wafer through a rotating mechanism, and controls its rotation during the rotating cleaning. This method can be used to clean the bottom of the entire wafer at one time, thereby improving the cleaning efficiency and reducing the complexity of cleaning. In addition, the ultra-pure water during the cleaning process will not affect the fixing mechanism, thereby reducing the time waste and equipment downtime caused by the ultra-pure water affecting the equipment during the cleaning process. Cleaning the back side of the wafer based on this method saves about 30%-50% of the time compared to the prior art.

[0132] On the other hand, an embodiment of the present application also provides a glue coating device, including the above-mentioned wafer cleaning device.

[0133] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A wafer cleaning device, characterized in that: Including cleaning mechanism and fixing mechanism; The fixing mechanism comprises a supporting structure, a limiting ring, a slider and a first preset number of clamps; the limiting ring is rotatably connected to the supporting structure; the slider is arranged on the inner side of the limiting ring, the number of the sliders matches the clamps, and the sliders and the clamps are arranged at intervals; the first preset number of clamps are movably connected to the supporting structure, and the first preset number of clamps are embedded in the inner side of the limiting ring; wherein the angles between two adjacent clamps are equal; the first preset number is greater than or equal to 4; The cleaning mechanism is arranged at the bottom of the wafer to be cleaned; The limiting ring is used to drive the slider to rotate on the supporting structure under the drive of external force, so as to drive the first preset number of clamps to move toward the center of the limiting ring, thereby fixing the wafer to be cleaned, and then using the cleaning mechanism to clean the bottom of the wafer to be cleaned.

2. The wafer cleaning device according to claim 1, characterized in that: The clamp comprises a clamp head and a clamp body, wherein the clamp head and the clamp body are fixedly connected; The chuck has a thickness of 4mm-6mm and a width of 50mm-60mm; The clamp body has a thickness of 3mm-5mm, a length of 40mm-50mm, and a width of 50mm-60mm; The material of the clamp body includes hard ceramics, and the material of the clamp head includes semiconductor ceramics.

3. The wafer cleaning device according to claim 1, characterized in that: The wafer cleaning device further comprises a driving mechanism, which is arranged outside the limiting ring and connected to the limiting ring for driving the limiting ring to rotate.

4. The wafer cleaning device according to claim 1, characterized in that: The cleaning mechanism comprises a cleaning brush plate and a base; The cleaning brush plate is circular, and the edge of the cleaning brush plate is tangent to the bottom edge of the wafer to be cleaned; The base is movably connected to the cleaning brush disc, and the base is arranged at the center of the bottom of the cleaning brush disc.

5. The wafer cleaning device according to claim 4, characterized in that: The difference between the diameter of the cleaning brush plate and the radius of the wafer to be cleaned is greater than or equal to 10 mm, so that the cleaning brush plate can cover the center of the wafer to be cleaned; The thickness of the cleaning brush plate is 40mm-50mm; The material of the cleaning brush plate includes absorbent cotton.

6. The wafer cleaning device according to claim 4, characterized in that: A second preset number of parallel cleaning sheets are fixedly arranged on the surface of the cleaning brush disc, and the distance between adjacent cleaning sheets is 10 mm-20 mm; Among the second preset number of parallel cleaning sheets, each cleaning sheet has a width of 4 mm to 6 mm and a raised edge height of 0.1 mm to 0.3 mm; The material of the cleaning sheet includes a hard plastic sheet.

7. The wafer cleaning device according to claim 4, characterized in that: At least one ultrapure water nozzle is also provided in the base for soaking the cleaning brush plate, and the flow rate of the ultrapure water nozzle is 100-200 ml / min.

8. The wafer cleaning device according to claim 4, characterized in that: The base is also provided with a rotating mechanism for driving the cleaning brush disc to rotate and clean along the bottom edge of the wafer to be cleaned, and driving the cleaning brush disc to rotate during the cleaning process; Among them, the rotation speed of rotary cleaning is 40r / min-100r / min, and the rotation speed is 4r / min-10r / min.

9. The wafer cleaning device according to claim 1, characterized in that: A nitrogen drying mechanism is provided on at least one side of the bottom of the limiting ring, for drying the cleaned wafer; The drying nitrogen flow rate is 1200ml / min-1500ml / min, and the drying temperature is 40℃-50℃.

10. A wafer cleaning method, implemented by the wafer cleaning device according to any one of claims 1 to 9, characterized in that: The method comprises: Transferring the wafer to be cleaned to the limiting ring, and controlling the center of the wafer to be cleaned to overlap with the center of the limiting ring; The limiting ring is driven by external force to drive the slider to rotate, so that the slider drives a first preset number of clamps to move toward the center of the limiting ring and fix the wafer to be cleaned; The bottom of the wafer to be cleaned is cleaned by the cleaning mechanism to obtain a cleaned wafer.

11. The method according to claim 10, characterized in that The wafer cleaning device comprises a rotating mechanism, the cleaning mechanism comprises a cleaning brush plate and a base, and the base is provided with at least one ultrapure water nozzle and a rotating mechanism; The step of cleaning the bottom of the wafer to be cleaned by the cleaning mechanism to obtain a cleaned wafer comprises: The cleaning brush plate is continuously infiltrated by the ultrapure water nozzle; during the cleaning process, the flow rate of the ultrapure water nozzle is 100ml / min-200ml / min; The cleaning brush is driven by the rotating mechanism to rotate and clean along the back edge of the wafer to be cleaned, and the cleaning brush is driven to rotate during the cleaning process until the bottom of the wafer to be cleaned is cleaned; wherein the rotation speed of the rotary cleaning is 40r / min-100r / min, and the rotation speed is 4r / min-10r / min.

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