A polishing liquid premixing device for semiconductor wafer processing

Abstract

This utility model discloses a premixing device for polishing slurry in semiconductor wafer processing, relating to the technical field of mixing devices. The premixing device includes a support platform, a stirring tank, a stirring motor, and a top cover. The stirring tank is inserted into the support platform, and the stirring motor is mounted on the top cover, which is located on top of the stirring tank. The support platform includes a base and a rotating motor, with a groove on the top of the base and the rotating motor engaging with the outside of the base. In this premixing device, the stirring tank and the stirring motor rotate in opposite directions, subjecting the polishing slurry to bidirectional shear force within the tank. This effectively breaks up unidirectional eddies, significantly shortening the mixing time and greatly improving mixing uniformity, thus meeting the high precision requirements of polishing slurry in semiconductor wafer polishing. The spiral guide strips and the counter-rotating propeller blades work together to form axial convection, and the baffles break up radial eddies; the combined effect of these three elements eliminates mixing dead zones.

Description

Technical Field

[0001] This utility model relates to the field of mixing device technology, specifically a premixing device for polishing slurry in semiconductor wafer processing. Background Technology

[0002] In the semiconductor wafer processing, chemical mechanical polishing is one of the key processes, and the uniformity of the polishing slurry directly affects the surface smoothness, roughness and defect rate of the wafer after polishing.

[0003] Existing polishing slurry premixing devices mostly adopt a unidirectional stirring structure, that is, the stirring component rotates while the stirring tank is fixed. This method easily leads to the formation of a unidirectional vortex in the polishing slurry inside the tank, resulting in mixing dead zones. This is especially true for polishing slurries containing nano-sized abrasives, making it difficult to achieve sufficient dispersion of abrasives and slurry. At the same time, polishing slurry is easily left on the inner wall of the fixed stirring tank, which not only wastes raw materials but also affects the mixing quality of subsequent batches of polishing slurry.

[0004] In addition, the stirring components and stirring tank of traditional devices lack stable positioning and coordination, which easily causes shaking during the stirring process, further reducing the mixing efficiency and failing to meet the high-precision mixing requirements of polishing fluid in semiconductor wafer processing. Utility Model Content

[0005] To address the shortcomings of existing technologies, this invention provides a premixing device for polishing slurry in semiconductor wafer processing, which solves the problems of insufficient mixing, low efficiency, easy residue, and poor stability in existing polishing slurry premixing devices.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a premixing device for polishing slurry in semiconductor wafer processing, comprising a support platform, a stirring tank, a stirring motor, and a top cover. The stirring tank is inserted into the support platform, and the stirring motor is mounted on the top cover, which is located at the top of the stirring tank. The support platform includes a base and a rotating motor. A groove is provided on the top of the base, and the rotating motor is engaged with the outside of the base. A transmission gear is sleeved on the outside of the output end of the rotating motor. The stirring tank is inserted into the inside of the groove, and a linkage gear is connected to the bottom of the stirring tank. The linkage gear meshes with the transmission gear, and the rotating motor drives the stirring tank to rotate in the opposite direction to the stirring motor.

[0007] Preferably, a bearing is inserted into the inner side of the groove, a rod is connected to the bottom of the mixing tank, the rod is inserted into the inner side of the bearing, and a support rod is connected to the top of the platform.

[0008] Preferably, a guide strip is connected to the inner wall of the mixing tank. The guide strip is spiral-shaped and evenly distributed around the inner wall of the mixing tank. A baffle plate is connected to the bottom of the inner side of the mixing tank. The baffle plate is evenly distributed around the inner side of the mixing tank. A positioning sleeve is provided inside the mixing tank and is located in the middle of the baffle plate.

[0009] Preferably, the output end of the stirring motor is connected to a shaft, the other end of which is inserted into the inner side of the positioning sleeve. A positioning ring is fitted onto the outer side of the shaft, and a propeller blade is connected to the outer side of the positioning ring. The propeller blade is in the opposite direction to the guide strip.

[0010] Preferably, the upper cover is sleeved on the outside of the shaft, the top of the upper cover is connected to a fixing sleeve for sleeved with the stirring motor, the bottom of the upper cover is provided with a slot for locking with the stirring tank, and the bottom of the upper cover is also provided with a locking block for locking with the support rod.

[0011] Its beneficial effects are as follows:

[0012] 1. The premixing device for polishing slurry in semiconductor wafer processing has a stirring tank and a stirring motor rotating in opposite directions, which makes the polishing slurry subject to bidirectional shear force in the tank, effectively breaking the unidirectional eddy current, greatly shortening the mixing time, and significantly improving the mixing uniformity, which can meet the high precision requirements of polishing slurry for semiconductor wafer polishing.

[0013] 2. The premixing device for polishing slurry in semiconductor wafer processing uses a spiral guide bar and a reverse propeller blade to form axial convection, and a baffle plate to break the radial vortex. The three work together to eliminate mixing dead zones and ensure that the abrasive and slurry are fully dispersed. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0016] Figure 2 This is a schematic diagram of the structure of the support platform of this utility model;

[0017] Figure 3 This is a schematic diagram of the internal structure of the mixing tank of this utility model;

[0018] Figure 4 This is a schematic diagram of the bottom structure of the mixing tank of this utility model;

[0019] Figure 5 This is a schematic diagram of the stirring assembly structure of this utility model;

[0020] Figure 6 This is a schematic diagram of the top structure of the cover of this utility model;

[0021] Figure 7 This is a schematic diagram of the bottom structure of the top cover of this utility model.

[0022] In the diagram: 1. Support platform; 11. Base; 111. Groove; 112. Bearing; 113. Support rod; 12. Rotating motor; 121. Transmission gear; 2. Mixing tank; 21. Guide strip; 22. Baffle plate; 23. Positioning sleeve; 24. Linkage gear; 25. Insert rod; 3. Mixing motor; 31. Shaft; 32. Positioning ring; 33. Propeller blade; 4. Top cover; 41. Fixing sleeve; 42. Slot; 43. Locking block. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions in the embodiments of this utility model are described clearly and completely. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0024] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0025] This utility model discloses a premixing device for polishing slurry in semiconductor wafer processing, according to the attached... Figure 1 As shown, it includes a support platform 1, a mixing tank 2, a stirring motor 3, and a top cover 4. The mixing tank 2 is inserted into the support platform 1, the stirring motor 3 is mounted on the top cover 4, and the top cover 4 is located on top of the mixing tank 2.

[0026] The mixing tank 2 and the stirring motor 3 rotate in opposite directions, causing the polishing slurry to be subjected to bidirectional shear force inside the tank, effectively breaking the unidirectional vortex, greatly shortening the mixing time, and significantly improving the mixing uniformity, which can meet the high precision requirements of the polishing slurry for semiconductor wafer polishing; the spiral guide strip 21 and the reverse propeller blade 33 cooperate to form axial convection, and the baffle plate 22 breaks the radial vortex. The three work together to eliminate mixing dead angles and ensure that the abrasive and the slurry are fully dispersed.

[0027] According to the appendix Figures 1-4As shown, the support platform 1 further includes a base 11 and a rotating motor 12. The base 11 is made of stainless steel and has good corrosion resistance and load-bearing capacity. The top of the base 11 has a groove 111 that fits the bottom of the mixing tank 2. A deep groove ball bearing 112 is inserted into the inside of the groove 111 to reduce the frictional resistance when the mixing tank 2 rotates. A rod 25 is welded to the bottom of the mixing tank 2 and is inserted into the inside of the bearing 112 to realize the rotatable connection between the mixing tank 2 and the base 11. Four support rods 113 are welded to the top of the base 11 to support the top cover 4.

[0028] According to the appendix Figures 1-2 As shown, the rotary motor 12 is snapped onto the outside of the base 11. A conventional servo motor is selected to achieve speed adjustment. A transmission gear 121 is connected to the outside of the output end of the rotary motor 12 via a key. A linkage gear 24 is welded to the outside of the bottom of the mixing tank 2. The linkage gear 24 and the transmission gear 121 have the same module and are meshed. When the rotary motor 12 is working, it drives the mixing tank 2 to rotate through gear transmission. The rotation direction of the mixing tank 2 is opposite to the rotation direction of the mixing motor 3.

[0029] According to the appendix Figures 1-3 As shown, specifically disclosed, five spiral guide strips 21 are welded to the inner wall of the mixing tank 2. The guide strips 21 are evenly distributed along the circumference of the inner wall of the mixing tank 2 to drive the polishing liquid to flow axially along the tank wall. Five baffles 22 are welded to the bottom inner side of the mixing tank 2. The baffles 22 are evenly distributed along the circumference to break the eddies formed by the polishing liquid and enhance convection mixing. A positioning sleeve 23 is welded to the center of the bottom inner side of the mixing tank 2 to position the shaft 31.

[0030] According to the appendix Figures 1-5 As shown, the output end of the stirring motor 3 is connected to a shaft 31, the other end of which is inserted into the inner side of the positioning sleeve 23, to achieve coaxial positioning of the stirring assembly and the stirring tank 2. A positioning ring 32 is interference-fitted to the outside of the shaft 31, and a propeller blade 33 is welded to the outside of the positioning ring 32. The spiral direction of the propeller blade 33 is opposite to that of the guide strip 21. When the stirring tank 2 drives the guide strip 21 to make the polishing liquid rise along the tank wall, the propeller blade 33 can drive the polishing liquid to flow downward along the center of the tank, forming bidirectional convection.

[0031] According to the appendix Figures 1-6As shown, it is particularly important to emphasize that the upper cover 4 is made of lightweight aluminum alloy and is sleeved on the outside of the shaft 31; a fixing sleeve 41 is welded to the top of the upper cover 4, which is interference-fitted with the housing of the stirring motor 3 to fix the stirring motor 3; a slot 42 adapted to the outer diameter of the top of the mixing tank 2 is opened at the bottom of the upper cover 4, which is engaged with the mixing tank 2 through the slot 42 to reduce the splashing of polishing liquid during the mixing process; a locking block 43 adapted to the support rod 113 is also welded to the bottom of the upper cover 4, which is engaged with the top of the support rod 113 to further improve the stability of the upper cover 4 and the stirring motor 3.

[0032] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0033] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A premixing device for polishing slurry in semiconductor wafer processing, comprising a support platform (1), a stirring tank (2), a stirring motor (3), and a top cover (4), wherein the stirring tank (2) is inserted into the support platform (1), the stirring motor (3) is mounted on the top cover (4), and the top cover (4) is located on top of the stirring tank (2), characterized in that, The support platform (1) includes a base (11) and a rotating motor (12). The base (11) has a groove (111) on its top. The rotating motor (12) is snapped onto the outside of the base (11). A transmission gear (121) is sleeved on the outside of the output end of the rotating motor (12). The stirring tank (2) is inserted into the inside of the groove (111). A linkage gear (24) is connected to the bottom of the stirring tank (2). The linkage gear (24) meshes with the transmission gear (121). The rotating motor (12) is used to drive the stirring tank (2) to rotate in the opposite direction to the stirring motor (3).

2. The premixing device for polishing slurry in semiconductor wafer processing according to claim 1, characterized in that, A bearing (112) is inserted into the inner side of the groove (111), a rod (25) is connected to the bottom of the mixing tank (2), the rod (25) is inserted into the inner side of the bearing (112), and a support rod (113) is connected to the top of the platform (11).

3. The premixing device for polishing slurry in semiconductor wafer processing according to claim 1, characterized in that, The inner wall of the mixing tank (2) is connected to a guide strip (21), which is spiral in shape and is evenly distributed around the inner wall of the mixing tank (2). A baffle plate (22) is connected to the bottom of the inner side of the mixing tank (2), which is evenly distributed around the inner side. A positioning sleeve (23) is provided inside the mixing tank (2), which is located in the middle of the baffle plate (22).

4. The premixing device for polishing slurry in semiconductor wafer processing according to claim 3, characterized in that, The output end of the stirring motor (3) is connected to a shaft (31), the other end of which is inserted into the inner side of the positioning sleeve (23). A positioning ring (32) is sleeved on the outer side of the shaft (31), and a propeller blade (33) is connected to the outer side of the positioning ring (32). The direction of the propeller blade (33) is opposite to that of the guide strip (21).

5. The polishing liquid pre-mixing device for semiconductor wafer processing according to claim 4, wherein The upper cover (4) is sleeved on the outside of the shaft (31). The top of the upper cover (4) is connected to a fixing sleeve (41) for sleeved on the stirring motor (3). The bottom of the upper cover (4) is provided with a slot (42) for locking the stirring tank (2). The bottom of the upper cover (4) is also provided with a locking block (43) for locking the support rod (113).

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