Wafer centering positioning device, transmission device, thinning equipment and centering method

Abstract

The present invention relates to a wafer centering and positioning device, a transmission device, a thinning device and a centering method. The wafer centering and positioning device comprises: a centering base plate, provided with linear guide rails distributed circumferentially and extending radially with the center of the wafer centering as the center; a centering turntable, arranged below the centering base plate and capable of rotating relative to the centering base plate, the center of rotation of the centering turntable is aligned with the center of the wafer centering, and the centering turntable is provided with an involute spiral guide rail; a centering stopper, provided with a stopper column extending out of the top surface of the centering base plate, the centering stopper is slidably mounted on the involute spiral guide rail and slidably mounted on the linear guide rail, when the centering turntable rotates, the centering stopper can slide along the involute spiral guide rail and the linear guide rail at the same time, and at each circumferential angle of the centering turntable, the center distance from each stopper column to the rotation center is always equal, which is used to push the wafer to the centering position. The present invention can realize the center positioning of wafers of different sizes, and is simple as a whole, operates smoothly, and has high repeatability positioning accuracy.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology; more specifically, the present invention relates to a wafer centering and positioning device, a wafer transfer device, a wafer thinning device and a wafer centering method. Background Art

[0002] In the manufacturing process of semiconductor-specific equipment, achieving automatic center positioning of the wafer is a key technology.

[0003] In modern production equipment, common methods of positioning the wafer center positioning device include V-shaped center positioning, rotation center positioning, etc. Among them: V-shaped center positioning has high requirements on the surface roughness of the V-shaped part and is difficult to process; the rotation center positioning device has a complex structure, is difficult to control, and is difficult to control, and the accuracy is difficult to guarantee, which makes the operation of wafer center positioning more troublesome. Summary of the invention

[0004] In view of this, the present invention provides a wafer centering and positioning device, a wafer transfer device, a wafer thinning equipment and a wafer centering method, so as to solve or at least alleviate one or more of the above-mentioned problems and other problems existing in the prior art.

[0005] In order to achieve the above-mentioned object, a first aspect of the present invention provides a wafer centering and positioning device, wherein the wafer centering and positioning device comprises:

[0006] A centering base, the centering base providing a wafer centering center, the centering base being provided with N linear guide rails distributed circumferentially and extending radially with the wafer centering center as the center, wherein N ≥ 3;

[0007] A centering turntable, which is disposed below the centering base and is rotatable relative to the centering base, the rotation center of the centering turntable is aligned with the wafer centering center, and the centering turntable is provided with an involute spiral guide rail; and

[0008] N centering blocks, each of which is provided with a stop column extending out of the top surface of the centering base, the N centering blocks are slidably mounted on the involute spiral guide rails and are slidably mounted on the N linear guide rails respectively, when the centering turntable rotates around the rotation center relative to the centering base plate, the centering block can slide along the involute spiral guide rails and the linear guide rails at the same time, and at each circumferential angle of the centering turntable, the center distance from each stop column to the rotation center is always equal, so as to push the wafer to the centering position.

[0009] In the wafer centering and positioning device as described above, optionally, the N linear guide rails are evenly distributed along the circumferential direction with the wafer centering center as the center of the circle.

[0010] In the wafer centering and positioning device as described above, optionally, the wafer centering and positioning device includes a frame and a drive motor, the centering base plate and the drive motor are fixedly mounted on the frame, and the drive motor is used to drive the centering turntable to rotate around the rotation center.

[0011] In the wafer centering and positioning device as described above, optionally, the frame includes a base and columns, the centering base is fixed to the base through the columns, the frame also includes a motor bracket, the motor bracket is installed on the base, the drive motor is fixed to the motor bracket, the columns are distributed on the periphery of the motor bracket, and leveling bolts are provided at the bottom periphery of the motor bracket for adjusting the horizontality of the motor bracket relative to the base.

[0012] In the wafer centering and positioning device as described above, optionally, the centering base is provided with a vacuum suction cup at the center of the wafer centering, for adsorbing and fixing the wafer that has been centered, and the top plane of the vacuum suction cup protrudes from the top surface of the centering base.

[0013] In the wafer centering and positioning device as described above, optionally, each of the centering blocks is provided with a pair of juxtaposed stopper columns, and a distance between the stopper columns is greater than an opening length of the notch of the wafer.

[0014] In the wafer centering and positioning device as described above, optionally, the involute spiral guide rail is a spiral groove, the linear guide rail is a guide shaft, an axially penetrating radial groove is provided in the centering base, the guide shaft is fixed in the radial groove, the bottom of the centering block has a protrusion suitable for extending into the spiral groove to slide along the spiral groove, and the centering block is sleeved on the guide shaft and located in the radial groove.

[0015] In the wafer centering and positioning device as described above, optionally, both ends of the guide shaft are respectively fixed to the centering base plate by means of top screws.

[0016] In the wafer centering and positioning device as described above, optionally, the centering block is mounted on the guide shaft via a linear bearing.

[0017] In the wafer centering and positioning device as described above, optionally, the involute spiral guide rail is an equidistant spiral guide rail, and at each rotation angle of the centering turntable, the center distance increments of the equidistant spiral guide rail are equal.

[0018] In the wafer centering and positioning device as described above, optionally, the position of the blocking column on the centering block is set so that when the centering block is installed on the wafer centering and positioning device, the distance between the blocking column on each centering block and the wafer centering center is the same.

[0019] In the wafer centering and positioning device as described above, optionally, a radial adjustment mechanism for the position of a stopper post is provided on the centering stopper, and the radial adjustment mechanism for the position of the stopper post is set with an adjustment mark according to the spacing angle of each centering stopper, so as to adjust and compensate for the radial displacement difference of the stopper post.

[0020] In the wafer centering and positioning device as described above, optionally, the centering turntable is provided with N involute spiral guide rails, the involute spiral guide rails have the same size and shape and are evenly arranged on the circumference, each of the centering blocks is respectively installed on a different involute spiral guide rail, and the centering blocks are evenly distributed along the circumference.

[0021] In the wafer centering and positioning device as described above, optionally, the centering base is located on the top of the wafer centering and positioning device.

[0022] In the wafer centering and positioning device as described above, optionally, a sensor is provided on the centering base plate, and the sensor is used to identify the size of the wafer, and the wafer centering and positioning device is configured to, after the sensor identifies the size of the wafer, control the drive motor to drive the centering block to move away from the wafer centering center to make room for placing the wafer, and after the base wafer to be centered is placed in place, drive the centering block to move toward the wafer centering center to perform the centering action.

[0023] In order to achieve the aforementioned objectives, the second aspect of the present invention provides a wafer transfer device, wherein the wafer transfer device includes a wafer centering and positioning device and a moving mechanism as described in any one of the aforementioned first aspects, the wafer centering and positioning device is used to adjust the wafer position, and the wafer centering and positioning device is connected to the moving mechanism so that the moving mechanism drives the wafer centering and positioning device to move.

[0024] In order to achieve the aforementioned object, a third aspect of the present invention provides a wafer thinning device, wherein the wafer thinning device comprises:

[0025] The front-end module is located at the front end of the wafer thinning equipment and is used to enable the wafer to enter and exit;

[0026] A grinding module, which is located at the end of the wafer thinning equipment and is used for grinding the wafer;

[0027] A polishing module, located between the front-end module and the grinding module, for chemical mechanical polishing of the wafer; and

[0028] The wafer transfer device as described in the second aspect is parallel to the polishing module and located between the front-end module and the grinding module.

[0029] In order to achieve the aforementioned object, a fourth aspect of the present invention provides a wafer centering method using the wafer centering and positioning device as described in any one of the aforementioned first aspects, wherein the method comprises the following steps:

[0030] The blocking pillars make room for wafer reception according to the size of the wafer;

[0031] Receiving the wafer on a vacuum chuck on a centering base;

[0032] Controlling the movement of the stopper to enable the stopper pillar to push the wafer to center; and

[0033] When the push action of the stopper reaches the wafer size, the centering stops.

[0034] The present invention provides a wafer centering and positioning device, a wafer transmission device, a wafer thinning device and a wafer centering method, which can realize center positioning of wafers of different sizes and are simple in overall operation, stable in operation and high in repeated positioning accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The disclosure of the present invention will become more apparent with reference to the accompanying drawings. It should be understood that these drawings are only for illustrative purposes and are not intended to limit the scope of protection of the present invention. In the drawings:

[0036] Figure 1 is a schematic perspective view of an embodiment of a wafer centering and positioning device according to the present invention;

[0037] Figure 2 yes Figure 1 A schematic detailed perspective view of a centering turntable of a wafer centering positioning device, wherein a vacuum suction cup, a guide shaft, and a centering stopper are also shown;

[0038] Figure 3 yes Figure 1 A schematic three-dimensional diagram of another angle of the wafer centering and positioning device;

[0039] Figure 4 yes Figure 1 A schematic three-dimensional diagram of a centering stopper of a wafer centering positioning device;

[0040] Figure 5 yes Figure 1 A schematic diagram of the installation of the centering stopper of the wafer centering positioning device on the guide shaft;

[0041] Figure 6 Schematically shows Figure 5Linear bearing between centering stopper and guide shaft;

[0042] Figure 7 Schematically shows Figure 5 Installation drawing of the center guide shaft on the centering base plate; and

[0043] Figure 8 A three-dimensional view of an embodiment of a wafer thinning device of the present invention is schematically shown, and a wafer transfer device is also shown in the middle.

[0044] Figure markings: 1-wafer centering positioning device; 2-centering base; 3-wafer centering center; 4-top surface; 5-linear guide; 6-centering turntable; 7-involute spiral guide; 8-centering block; 9-stop column; 10-frame; 11-drive motor; 12-base; 13-column; 14-motor bracket; 15-leveling bolt; 16-vacuum suction cup; 17-radial groove; 18-protrusion; 19-top screw; 20-linear bearing; 23-sensor; 30-wafer; 31-grinding module; 32-third manipulator; 33-second position; 34-wafer transfer device; 35-first position; 36-second manipulator; 37-buffer module; 38-front end module; 39-first manipulator; 40-processing unit; 41-polishing module; 42-grinding workbench. DETAILED DESCRIPTION

[0045] With reference to the accompanying drawings and specific embodiments, the structure, composition, characteristics and advantages of the wafer centering positioning device, wafer transfer device, wafer thinning equipment and wafer centering method of the present invention will be explained in an exemplary manner below. However, all descriptions should not be used to form any limitations on the present invention.

[0046] For any single technical feature described or implied in the embodiments mentioned in this document, or any single technical feature displayed or implied in the accompanying drawings, the present invention still allows any combination or deletion between these technical features (or their equivalents) without any technical obstacles, and thus it should be considered that these more embodiments according to the present invention are also within the scope of the description of this document.

[0047] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features.

[0048] Figure 1 is a schematic perspective view of an embodiment of a wafer centering and positioning device according to the present invention.

[0049] As shown in the figure, in this embodiment, the wafer centering and positioning device 1 may include a centering base plate 2, a frame 10 and Figure 2 The centering turntable 6 shown in FIG. 2 is fixed on the frame 10. When the wafer centering positioning device 1 is working, the centering turntable 6 rotates relative to the centering base 2, and the centering stopper 8 is affected by the following Figure 2 The spiral guide rail 7 on the centering turntable 6 shown in FIG. Figure 1 Under the cooperation of the linear guide rail 5 on the centering base plate 2 shown in the figure, the centering block 8 drives the stopper 9 to push the wafer to be centered (not shown) at various angles, thereby realizing the centering of the wafer. After the centering is completed, the vacuum suction cup 16 absorbs the wafer and fixes it in place for subsequent operations.

[0050] As can be seen from the figure, in this example, the centering base 2 is circular, providing a wafer centering center 3. Other centering base shapes may also be used in other embodiments. The centering center 3 may be aligned with the center of the vacuum chuck 16, and may be aligned with the rotation center of the centering turntable 6.

[0051] In this example, the centering base 2 is located on the top of the wafer centering and positioning device 1, providing more operating space, facilitating the placement and taking of the wafer by a robot or the like, and also facilitating possible grinding, polishing and other operations.

[0052] The centering base 2 is provided with N linear guides 5 distributed circumferentially and extending radially with the wafer center 3 as the center. These linear guides 5 can be evenly distributed. In the illustrated example, N=3. It can be understood that in an optional embodiment, it can be set to N≥3; for example, 3 of them can be selected as the main centering blocks for installing the linear guides, and the rest can be used to install auxiliary centering blocks, so as to improve the centering efficiency and centering accuracy. It can also be clearly seen from the figure that the linear guide 5 is located in the radial groove 17 that penetrates axially, so that the stopper 9 on the centering block 8 can extend out of the top surface of the centering base 2. In some embodiments, it can also be arranged that the centering block 8 is not in the radial groove 17, and only the stopper 9 passes through these radial grooves 17.

[0053] Corresponding to the N linear guides 5, N centering blocks 8 can be provided in the wafer centering and positioning device. In the illustrated example, there are three centering blocks 8. As can be seen from the figure, each centering block 8 is provided with a stopper 9 extending out of the top surface 4 of the centering base 2. Optionally, each centering block 8 can be provided with a pair of juxtaposed stopper columns 9, and the spacing between the pair of stopper columns 9 is greater than the opening length of the notch of the wafer. If only a single stopper column 9 is provided, if the notch of the wafer is against the stopper column 9, there is a risk that it cannot be clamped or cannot be held in place. This situation can be avoided by providing two pairs of stopper columns 9. Even if one of the stopper columns 9 is supported by the notch of the wafer, the other stopper column 9 can still play a centering role.

[0054] The linear guide rails 5 in the figure are all located in the radial direction of the centering base plate 2, toward the centering center on the centering base plate 2. The radial groove 17 faces the same direction as the linear guide rail 5.

[0055] According to the illustrated example, the centering block 8 is slidably mounted on the involute spiral guide rail 7 (see Figure 2 ) and are slidably mounted on the same number of linear guide rails 5. When the centering turntable 6 rotates around the rotation center relative to the centering base plate 2, the centering stopper 8 can slide along the involute spiral guide rail 7 and the linear guide rail 5 at the same time, so that the stopper column 9 pushes the wafer to center.

[0056] The figure also shows a frame 10 and a drive motor 11 of the wafer centering and positioning device 1. The frame 10 is used to provide support for the wafer centering and positioning device 1, and to place the wafer centering and positioning device 1 in an appropriate position, such as but not limited to being placed on the ground, placed in a wafer thinning and polishing integrated machine, etc. The centering base plate 2 and the drive motor 11 can be installed on the frame 1, and the centering base plate 2 and the drive motor 11 can be fixed relative to the frame. The drive motor 11 is used to drive the centering turntable 6 to rotate around the rotation center.

[0057] The frame 10 includes a base 12 and columns 13. The figure shows a circular base 12, and the columns 13 are evenly distributed on the circumference of the base 13, and three columns are shown in the figure. In other embodiments, it can also be a different number, such as four or more. The centering base 2 is fixed to the base 12 through the columns 13. As can be seen from the figure, the frame 10 also includes a motor bracket 14, and the motor bracket 14 includes four columns in this example. The motor bracket 14 is installed on the base 12 and is located at the inner circumference surrounded by the columns 13. The drive motor 11 is fixed to the motor bracket 14, specifically inside it. The columns 13 are distributed on the outer circumference of the motor bracket 14. Leveling bolts 15 are provided at the bottom periphery of the motor bracket 14, which are used to adjust the level of the motor through the motor bracket 14 relative to the base 12 to ensure the centering accuracy. In order to effectively level, the drive motor 11 can be installed on the top of the motor bracket 14 at the top, and the bottom of the drive motor can be suspended, so that the bottom of the drive motor 11 does not form additional constraints during leveling.

[0058] The centering base 2 is provided with a vacuum suction cup 16 at the wafer centering center 3 for adsorbing and fixing the wafer after centering. Although the vacuum suction cup 16 is shown as a circle, it is not limited to this in the optional embodiments, and can be a square or other polygons. The vacuum suction cup 16 has an air hole for vacuuming, which is shown in the figure as a circle or a groove along the diameter direction. If it is necessary to determine the position of the wafer with a vacuum suction cup in some embodiments, the vacuum suction cup can be higher than the top surface 4, and it protrudes.

[0059] The position of the stopper 9 on the centering block 8 is set so that when the centering block 8 is installed on the wafer centering positioning device 1, the distance between the stopper 9 on each centering block 8 and the wafer centering center 3 is the same. This setting enables each centering stopper 9 to push the wafer to the edge of each angle at the same distance from the wafer centering center, that is, the center of the wafer is aligned with the centering center of the centering base 2. After the wafer is pushed to the centering position by the stopper 9, the vacuum suction cup 16 absorbs the wafer and fixes it in place.

[0060] Furthermore, in the illustrated example, a sensor 23 is also provided on the centering base plate 2. The sensor 23 can be used to identify the size of the wafer. At this time, the wafer centering positioning device 1 can be configured such that, after the sensor 23 identifies the size of the wafer, such as an 8-inch wafer or a 12-inch wafer, the feedback control driving motor 11 drives the centering turntable 6 in reverse so that the stopper 9 of the centering stopper 8 retreats on the centering base plate 2 to make room for placing the wafer, and after the base wafer to be centered is placed in place, the driving motor 11 is driven forward according to the size information of the wafer so that the centering turntable 6 rotates toward the center to tighten the centering stopper 8 for centering. The retreat of the stopper 9 can advantageously prevent the wafer from being placed unevenly by mistake, and centering can be performed according to the specific wafer size, thereby preventing centering failure, fragments, wafer slippage, etc. due to insufficient or excessive centering.

[0061] In an optional embodiment, the sensor 23 may be omitted. In this case, after each wafer centering operation is completed and before the next centering operation is performed, the centering block 8 may drive the stopper column 9 to retreat once, thereby providing sufficient accommodation space for the wafer.

[0062] Figure 2 yes Figure 1 A schematic detailed stereoscopic view of the centering turntable of the wafer centering positioning device, which also shows the vacuum suction cup, guide shaft, and centering stopper.

[0063] As shown in the figure, in this example, the centering turntable 6 is circular as a whole. In an optional embodiment, other suitable shapes can also be selected. A groove-shaped involute spiral guide 7, a centering block 8 engaged with it and worn on the linear guide 5, and a vacuum suction cup 16 aligned with the rotation center of the centering turntable 6 are shown on the centering turntable 6. In an optional embodiment, the involute spiral guide 7 can also be a spiral rod-shaped guide, a convex spiral guide, etc., and a structure of complementary shape can be designed on the centering block 8 accordingly. The two cooperate with each other. When the centering turntable 6 rotates, since the centering block 8 engages the linear guide of the centering base plate 2, it does not change the angular position with the rotation of the centering turntable 6, but moves synchronously radially along the linear guide 5 to center the wafer. This centering method advantageously reduces the control difficulty of the wafer center positioning device, making it simple in structure and high in positioning accuracy, and the device has the advantages of stable operation and easy use.

[0064] In one embodiment of the present invention, a centering turntable having equal-pitch spiral grooves is rotated so that an embedded centering block matching the spiral grooves contracts or expands toward the center under the action of a guide shaft. Since different positions of the spiral grooves are at different distances from the center of the turntable, to achieve the centering function, it is also necessary to control the different positions of the two baffles above the centering baffle on the centering baffle, so that the distances between the baffles on the block and the center of the turntable are ultimately consistent.

[0065] Specifically, in this example, the involute spiral guide 7 is an equidistant spiral guide. It can be seen from the figure that at each rotation angle of the centering turntable 6, the center distance increments of the equidistant spiral guide are equal. In this case, at different angles of the centering turntable 6, the distances from the spiral guide 7 at each position to the rotation center are not the same; in order to compensate for these distance differences, it can be designed that the positions of each pair of stoppers 9 on the corresponding centering block 8 are not the same. Specifically, the position of the stopper 9 on one of the centering blocks 8 can be used as a reference, so that the stopper on the centering block close to the center position is displaced outward for compensation, and the stopper on the centering block far from the center position is displaced inward for compensation, so that the stopper on each group of centering blocks is always at the same distance from the center position, so that the centering operation of the wafer can be completed by rotating the centering turntable 2.

[0066] The radial position of the stopper 9 on each stopper 8 can be fixed according to the compensation distance during manufacturing. The compensation distance is calculated based on the circumferential spacing angle between the stoppers 8 and the radial increment generated by the involute spiral guide 7 with the circumferential angle, so as to ensure that the distances from the stopper 9 on each stopper 8 to the wafer center 3 are equal. Or the stopper 9 can be set to be radially movable and adjustable, for example, the adjustment mark position is set according to the spacing angle. In order to mass produce the centering stopper 8, so that each centering stopper 8 can be applied to each linear guide 5, it can be set that the stopper 9 on the centering stopper 8 is adjustable along the direction of the linear guide 5. In this way, the adjustment of the stopper 9 can compensate for the different distances of the spiral guide from the center position at different phases. For example, the stopper 9 can perform stepless position adjustment or graduated position adjustment on the centering stopper 8. In order to perform graduated adjustment, a scale can also be marked on the centering stopper 8 to align the compensation position according to the compensation amount required for different phases.

[0067] In an optional embodiment, a radial adjustment mechanism for the position of a stopper column may be provided on the centering stopper 8. The radial adjustment mechanism for the position of the stopper column may be provided with adjustment marks according to the spacing angles of the centering stoppers 8 as described above, so as to adjust and compensate for the radial displacement difference of the stopper column 9.

[0068] Combination Figure 2 and Figure 1 It can be understood that in the assembled wafer centering and positioning device 1, the centering turntable 6 is arranged below the centering base plate 2 and can rotate relative to the centering base plate 2. The rotation center of the centering turntable 6 is aligned with the wafer centering center 3. The centering turntable 6 is provided with an involute spiral guide rail 7. The centering block 8 is pushed by the spiral guide rail 7 and moves radially along the linear guide rail 5 to realize wafer centering. In the illustrated embodiment, at each circumferential angle of the centering turntable 6, the center distance from each stop column 9 to the rotation center is always equal, which is used to push the wafer to the centering position. Here, the involute spiral guide rail 7 is a spiral groove, and the linear guide rail 5 is a guide shaft.

[0069] In other embodiments, the involute spiral guide 7 is not limited to the equidistant spiral guide shown in the figure. For example, the same number of spiral guides as the centering blocks 8 may be provided, and the involute trajectories of each spiral guide are the same, but they may be at different phases at equal distances along the circumference with respect to the center position, so that when the centering turntable is rotated, the centering blocks on each spiral guide move synchronously and are at a constant distance from the center position. That is, the centering turntable 6 may be provided with N involute spiral guides 7, which have the same size and shape and are evenly arranged on the circumference, and each centering block 8 is respectively installed on a different involute spiral guide 7, and the centering blocks 8 are evenly distributed along the circumference. The advantage of such a setting is that the design of the stop column 9 can be simplified, and the position of the stop column on each centering block 8 does not need to be adjusted.

[0070] Figure 3 yes Figure 1 A schematic three-dimensional diagram of another angle of the wafer centering and positioning device. The diagram shows the centering base plate 2, the centering turntable 6, the column 13 in the frame 10, the motor bracket 14, etc.

[0071] This figure is a perspective from below the centering base plate 2 and the centering turntable 6, showing the relative positional relationship between the centering base plate 2 and the centering turntable 6. The centering base plate 2 and the centering turntable 6 are not connected to each other, so while the centering base plate 2 is fixed, the centering turntable 6 can rotate relative to the centering base plate 2 under the drive of the drive motor 11. Figure 1 and Figure 2 As described above, when the centering turntable 6 rotates relative to the centering base plate 2, the involute spiral guide rail 7 will push each centering block 8 to slide along the linear guide rail 5 toward the center position, and the blocking column 9 will push the wafer to achieve wafer centering.

[0072] The figure also partially shows the radial grooves, linear guide rails and motor brackets on the centering base plate 2. Figure 1 , Figure 2 The corresponding descriptions can more clearly understand the working principles and functions of these features, which will not be repeated here.

[0073] Figure 4 yes Figure 1 A schematic three-dimensional diagram of the centering stopper of the wafer centering positioning device.

[0074] In this example, the centering stopper 8 comprises a block-shaped body, a stopper column 9 located on the upper surface of the block-shaped body, and a protrusion 18 located on the lower surface of the block-shaped body. The width of the block-shaped body of the centering stopper 8 is suitable for fitting into the radial groove 17 of the centering base plate 2. The ratio between the length of the centering stopper 8 and the length of the radial groove 17 enables the centering stopper 8 to have sufficient sliding space in the radial groove 17 and to move a required distance therein.

[0075] The protrusion 18 is complementary in shape to the involute spiral guide 7 of the centering turntable 6. Figure 1 The example shows that the involute spiral guide rail 7 is in the form of a spiral groove, so a protrusion 18 is formed on the lower surface of the block-shaped body to cooperate with it. The protrusion 18 below the centering block 8 can be embedded in the spiral groove, and the centering block 8 and the stop column 9 are driven as the spiral groove rotates; the spiral groove can be through or not through, as long as the protrusion 18 can be embedded in the spiral groove. In an optional embodiment, if the involute spiral guide rail 7 is in other forms, such as a protruding track or a rod, the protrusion 18 can be deformed into a groove or a through hole to cooperate with it.

[0076] The number of the protrusions 18 and the stopper posts 9 can be set as required. In addition, as described above, the position of the post 9 on the centering stopper 8 can be designed to be adjustable to compensate for the distance difference between the spiral guide rail and the center position at each phase.

[0077] The figure also shows a through hole on the block body of the centering block for the linear guide rail 5 to pass through. The linear guide rail 5 can pass through the through hole directly or through a linear bearing, which will be described in detail below.

[0078] Figure 5 yes Figure 1 Schematic installation diagram of the centering block of the wafer centering positioning device on the guide shaft. The figure shows the centering base plate 2, the wafer 30, the centering block 8, the column 9, the linear guide rail 5, and the linear bearing 20.

[0079] As can be seen from the figure, the centering block 8 is installed on the guide shaft, i.e., the linear guide rail 5, through the linear bearing 20. The column 9 pushes against the edge of the wafer 30. When the centering turntable 6 rotates and the spiral guide rail pushes the centering block 8, the centering block 8 can move along the radial groove 7 to push against the wafer. The figure only shows the centering block 8 of one phase; it can be understood that when the centering turntable 6 rotates, the centering blocks 8 of each phase will simultaneously approach and push the wafer toward the edge of the wafer. In this application, phase refers to the position along the circumference.

[0080] Figure 6 Schematically shows Figure 5 Linear bearing between centering stop and guide shaft.

[0081] Combination Figure 5 It can be clearly seen that the centering block 8 is slidably connected to the guide shaft, i.e., the linear guide rail 5, via a linear bearing 20. The linear bearing 20 comprises an end portion having two connecting holes as shown in the figure and a cylindrical body portion having a through hole for the linear guide rail 5 to pass through.

[0082] Specifically, as shown in the figure, the end of the linear bearing 20 has two through holes for connection, and a through hole penetrating the bearing for the linear guide rail 5 to pass through is shown in the middle.

[0083] Combination Figure 5 It can be seen that the linear bearing 20 can be connected to the end bolts of the centering block 8 through the two through holes at the end. Without the use of the linear bearing 20, the direct friction between the centering block and the guide shaft, i.e., the linear guide rail, will cause the hole where the centering block and the guide shaft match to gradually become larger, affecting the centering accuracy, and the direct friction is likely to cause abnormal noise; the linear bearing 20 is used because there are balls in the bearing, and the linear bearing is derived from the use of the linear motion with the shaft, so it slides smoothly, has a stable structure, and has high repeatability.

[0084] Figure 7 Schematically shows Figure 5 Installation diagram of the center guide shaft on the centering base.

[0085] The figure shows a centering base 2, radial grooves 17, centering blocks 8, linear bearings 20, and a top screw 19 for fixing the guide shaft. As shown in the figure, the two ends of the guide shaft are fixed to the centering base 2 by top screws 19. Radial holes are formed from the outer peripheral edge of the centering base 2, and two sections of radial holes are respectively located at the two ends of the radial grooves 17, and the guide shaft can extend from the outer peripheral edge of the centering base 2. This arrangement can facilitate the disassembly, assembly and replacement of the guide shaft. The top screw 19 is fixed from the back side of the centering base 2, which can avoid leaving unnecessary structures on the top surface of the centering base, destroying the flatness, and accidentally affecting production.

[0086] The wafer center positioning device of the present invention can be used in a wafer thinning device. In the wafer thinning device, a transmission mechanism takes out a wafer from a wafer storage box, and then transmits and places the wafer on the wafer center positioning device of the present invention. After the wafer center positioning device of the present invention is centered, a robot arm takes the wafer away from the wafer center positioning device of the present invention. The wafer center positioning device can be used at any desired position of the wafer thinning device.

[0087] The wafer center positioning device of the present invention comprises a centering base plate and a centering turntable, a radial groove is opened in the centering base plate and a linear guide rail is installed, a spiral guide rail is arranged on the centering turntable, and when the centering turntable rotates relative to the centering base plate, the linear guide rail and the spiral guide rail work together to make the blocking column of the centering block push the wafer to the center position, thereby realizing the centering positioning of the wafer. This embodiment of the present invention can realize the center positioning of wafers of different sizes, and is simple in overall operation, stable in operation, and has high repeatability positioning accuracy.

[0088] One aspect of the present invention further provides a wafer centering method using a wafer centering positioning device as described in any of the aforementioned embodiments, wherein the method comprises the following steps: a blocking column makes room for receiving wafers according to the size of the wafer; receiving the wafer on a vacuum suction cup on a centering base; controlling the movement of the blocking block to allow the blocking column to push the wafer to be centered; and stopping the centering when the pushing action of the blocking column reaches the wafer size. In the step of the blocking column making room for receiving wafers according to the size of the wafer, it can be achieved by sensor induction control, and the sensor can be set on the centering base. In the step of receiving the wafer on the vacuum suction cup on the centering base, the wafer can be placed on the vacuum suction cup by a robot. In the step of controlling the movement of the blocking block to allow the blocking column to push the wafer to be centered, it can be achieved by as Figure 1 The driving motor shown in the figure drives the stopper to realize. In the step of stopping the centering when the pushing action of the stopper column reaches the wafer size, the blocking pushing distance is determined by the predetermined size, which can advantageously prevent the wafer from breaking.

[0089] Figure 8 A three-dimensional view of an embodiment of a wafer thinning device of the present invention is schematically shown, and a wafer transfer device is also shown in the middle.

[0090] The wafer transfer device 34 shown in the figure includes a moving mechanism 200 and a wafer centering and positioning device 1 according to the present invention. Figure 8 As shown. The wafer centering and positioning device 1 is connected to the moving mechanism 200, and the moving mechanism 200 drives the wafer centering and positioning device 1 to move so as to realize the transmission of the wafer. As an embodiment of the present invention, the moving mechanism 200 is a linear module, and the moving mechanism 200 accelerates or decelerates to move. The wafer centering and positioning device 1 arranged on the moving mechanism 200 can effectively maintain the centering position of the wafer during the transmission process, avoid the position of the wafer being offset during the transmission process, prevent the wafer from sliding off the wafer centering and positioning device 1, and ensure the stability of the wafer transmission.

[0091] As another aspect of the present invention, the present invention also provides a wafer thinning device, such as Figure 8 As shown, the wafer thinning equipment includes a front-end module 38, which is located at the front end of the wafer thinning equipment and is used to realize the entry and exit of the wafer; a grinding module 31, which is located at the end of the wafer thinning equipment and is used for grinding the wafer; a polishing module 41, which is located between the front-end module 38 and the grinding module 31 and is used for chemical mechanical polishing of the wafer; it also includes the wafer transfer device 34 mentioned above, which is parallel to the polishing module 41 and is located between the front-end module 38 and the grinding module 31.

[0092] exist Figure 8In the illustrated embodiment, the wafer thinning device further comprises a buffer module 37, which is disposed adjacent to the front-end module 38 and between the front-end module 38 and the wafer transfer device 34. In some embodiments, the buffer module 37 may be provided with the wafer centering and positioning device 1 of the present invention.

[0093] The wafer is transferred from the front-end module 38 to the buffer module 37 by the first robot 39; the wafer in the buffer module 37 is transferred from the buffer module 37 to the wafer centering and positioning device 1 of the wafer transfer device 34 by the second robot 36; the position of the wafer is adjusted in the wafer centering and positioning device 1 so that the wafer is concentric with the base of the wafer centering and positioning device 1; the moving mechanism of the wafer transfer device 34 drives the wafer to move from a first position 35 close to the buffer module 37 to a second position 33 close to the grinding module 31, and the second position 33 is the wafer centering and positioning device 1 represented by a dotted line; the third robot 32 transfers the wafer located at the second position 33 to the grinding workbench 42 of the grinding module 31.

[0094] Since the wafer centering and positioning device 1 of the wafer transfer device 34 effectively maintains the position of the wafer, the wafer rotated by the third manipulator 32 has a high concentricity with the grinding table 42, further ensuring the concentricity of the wafer and the grinding table 42. The wafer completely covers the negative pressure adsorption area on the grinding table 42 to avoid the occurrence of "leakage" and effectively ensure the reliability of wafer adsorption; the concentric arrangement of the wafer and the grinding table 42 is also conducive to ensuring the consistency of the contact arc length of the wafer grinding, improving the stability of the grinding force, and effectively controlling the quality of the grinding surface.

[0095] The drawings of this specification are schematic diagrams, which assist in explaining the concept of the present invention and schematically show the shapes of various parts and their mutual relationships. It should be understood that in order to clearly show the structures of various components of the embodiments of the present invention, the drawings are not drawn according to the same scale, and the same reference numerals are used to represent the same parts in the drawings.

[0096] The technical scope of the present invention is not limited to the contents of the above description. Those skilled in the art can make various deformations and modifications to the above implementation without departing from the technical idea of ​​the present invention, and these deformations and modifications should all fall within the scope of the present invention.

Claims

1. A wafer centering and positioning device, characterized in that: The wafer centering and positioning device comprises: A centering base (2), the centering base (2) providing a wafer centering center (3), the centering base (2) being provided with N linear guide rails (5) distributed circumferentially and extending radially with the wafer centering center (3) as the center, wherein N ≥ 3; a centering turntable (6), the centering turntable (6) being arranged below the centering base plate (2) and being rotatable relative to the centering base plate (2), the rotation center of the centering turntable (6) being aligned with the wafer centering center (3), the centering turntable (6) being provided with an involute spiral guide rail (7); and N centering blocks (8), each of the centering blocks (8) being provided with a stopper column (9) extending out of the top surface (4) of the centering base plate (2), the N centering blocks (8) being slidably mounted on the involute spiral guide rail (7) and being slidably mounted on the N linear guide rails (5), respectively, when the centering turntable (6) rotates around the rotation center relative to the centering base plate (2), the centering block (8) can slide along the involute spiral guide rail (7) and the linear guide rail (5) at the same time, and at each circumferential angle of the centering turntable (6), the center distance from each stopper column (9) to the rotation center is always equal, so as to push the wafer to the centering position; The blocking column (9) is arranged to be radially movable and adjustable, and a blocking column position radial adjustment mechanism is arranged on the centering block (8). The blocking column position radial adjustment mechanism is provided with an adjustment mark position according to the spacing angle of each of the centering blocks (8), and is used to adjust and compensate for the radial displacement difference of the blocking column (9).

2. The wafer centering and positioning device according to claim 1, characterized in that: The N linear guide rails (5) are evenly distributed along the circumferential direction with the wafer centering center (3) as the center of the circle.

3. The wafer centering and positioning device according to claim 1, characterized in that: The wafer centering and positioning device comprises a frame (10) and a drive motor (11); the centering base plate (2) and the drive motor (11) are fixedly mounted on the frame (10); and the drive motor (11) is used to drive the centering turntable (6) to rotate around the rotation center.

4. The wafer centering and positioning device according to claim 3, characterized in that: The frame (10) comprises a base (12) and columns (13), the centering base plate (2) being fixed to the base (12) via the columns (13), the frame (10) further comprising a motor bracket (14), the motor bracket (14) being mounted on the base (12), the drive motor (11) being fixed to the motor bracket (14), the columns (13) being distributed on the periphery of the motor bracket (14), and leveling bolts (15) being provided at the periphery of the bottom of the motor bracket (14) for adjusting the horizontality of the motor bracket (14) relative to the base (12).

5. The wafer centering and positioning device according to claim 1, characterized in that: The centering base (2) is provided with a vacuum suction cup (16) at the center (3) of the wafer centering, for adsorbing and fixing the wafer that has been centered, and the top plane of the vacuum suction cup (16) protrudes from the top surface (4) of the centering base (2).

6. The wafer centering and positioning device according to claim 1, characterized in that: A pair of juxtaposed stopper columns (9) are provided on each of the centering stopper blocks (8), and the spacing between the stopper columns (9) is greater than the opening length of the notch of the wafer.

7. The wafer centering and positioning device according to claim 1, characterized in that: The involute spiral guide rail (7) is a spiral groove, the linear guide rail (5) is a guide shaft, an axially penetrating radial groove (17) is provided in the centering base plate (2), the guide shaft is fixed in the radial groove (17), the bottom of the centering block (8) has a protrusion (18) suitable for extending into the spiral groove to slide along the spiral groove, and the centering block (8) is sleeved on the guide shaft and located in the radial groove (17).

8. The wafer centering and positioning device according to claim 7, characterized in that: Both ends of the guide shaft are fixed to the centering base plate (2) via jack screws (19) respectively.

9. The wafer centering and positioning device according to claim 7, characterized in that: The centering block (8) is mounted on the guide shaft via a linear bearing (20).

10. The wafer centering and positioning device according to any one of claims 1 to 9, characterized in that: The involute spiral guide rail (7) is an equidistant spiral guide rail, and at each rotation angle of the centering turntable (6), the center distance increments of the equidistant spiral guide rail are equal.

11. The wafer centering and positioning device according to claim 10, characterized in that: The position of the stop column (9) on the centering stop block (8) is arranged so that, when the centering stop block (8) is mounted on the wafer centering positioning device, the distance between the stop column (9) on each centering stop block (8) and the wafer centering center (3) is the same.

12. The wafer centering and positioning device according to any one of claims 1 to 9, characterized in that: The centering turntable (6) is provided with N involute spiral guide rails (7), the involute spiral guide rails have the same size and shape and are evenly arranged on the circumference at a graduated scale, each of the centering stoppers (8) is respectively installed on a different involute spiral guide rail (7), and the centering stoppers (8) are evenly distributed along the circumference.

13. The wafer centering and positioning device according to any one of claims 1 to 9, characterized in that: The centering base plate (2) is located on the top of the wafer centering positioning device.

14. The wafer centering and positioning device according to claim 3 or 4, characterized in that: A sensor (23) is provided on the centering base plate (2), and the sensor (23) is used to identify the size of the wafer. In addition, the wafer centering positioning device is configured to, after the sensor (23) identifies the size of the wafer, control the drive motor (11) to drive the centering block (8) to move away from the wafer centering center to make room for placing the wafer, and after the base wafer to be centered is placed in place, drive the centering block (8) to move toward the wafer centering center to perform the centering action.

15. A wafer transfer device, characterized in that: The wafer transfer device comprises a wafer centering and positioning device as described in any one of claims 1 to 14 and a moving mechanism, wherein the wafer centering and positioning device is used to adjust the position of the wafer, and the wafer centering and positioning device is connected to the moving mechanism so that the moving mechanism drives the wafer centering and positioning device to move.

16. A wafer thinning device, characterized in that: The wafer thinning equipment comprises: The front-end module is located at the front end of the wafer thinning equipment and is used to enable the wafer to enter and exit; A grinding module, which is located at the end of the wafer thinning equipment and is used for grinding the wafer; A polishing module, located between the front-end module and the grinding module, for chemical mechanical polishing of the wafer; and The wafer transfer device as claimed in claim 15 is parallel to the polishing module and located between the front-end module and the grinding module.

17. A wafer centering method using the wafer centering and positioning device according to any one of claims 1 to 14, characterized in that: The method comprises the following steps: The blocking pillars make room for wafer reception according to the size of the wafer; Receiving the wafer on a vacuum chuck on a centering base; Controlling the movement of the stopper so that the stopper column pushes the wafer to center; as well as When the push action of the stopper reaches the wafer size, the centering stops.

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