Wafer polishing method and wafer polishing machine

Abstract

The application discloses a wafer grinding method and a wafer grinding machine. The wafer grinding machine comprises a wafer supporting table for supporting a wafer to be ground and a grinding wheel for grinding the wafer. The wafer grinding method comprises the following steps: according to coordinate data of the wafer supporting table and specification data of the grinding wheel, the wafer supporting table is controlled to move relative to the grinding wheel to a position where an axis of the wafer is tangent to an outer edge of a projection circle of the grinding wheel; the diameter of the grinding wheel is smaller than the radius of the wafer; and the grinding wheel is made to contact a surface to be ground of the wafer, the grinding wheel and / or the wafer supporting table are driven to rotate relative to each other to grind the wafer, so as to form a ring-shaped area with a relatively large thickness relative to the surface to be ground on the edge of the wafer, and the ring width of the ring-shaped area is the difference between the radius of the wafer and the diameter of the grinding wheel.

Description

Technical Field

[0001] This application relates to the technical field of semiconductor processing, specifically to the field of wafer grinding technology, and particularly to a wafer grinding method and a wafer grinding machine. Background Technology

[0002] In semiconductor manufacturing, wafer grinding is generally performed using a wafer grinding machine. There are various existing wafer grinding processes, one of which is the TAIKO grinding process. Specifically, when grinding a wafer, a ring-shaped area is pre-set on the grinding surface of the wafer. This ring-shaped area is located at the edge of the wafer along its circumference. The grinding wheel grinds within this ring-shaped area to thin the wafer. After grinding, a protrusion is formed on the surface of the wafer, also located at the edge of the wafer along its circumference.

[0003] In existing technologies, wafers come in various sizes, and the width of the pre-set annular area on wafers of different sizes is the same. Therefore, in order to grind wafers of different sizes on the same wafer grinding machine, it is necessary to add a step of changing grinding wheels of different sizes to the grinding method of the wafer grinding machine. That is, after placing wafers of different sizes on the wafer support table, it is necessary to change to a grinding wheel that matches the size of the wafer placed on the wafer support table. However, if only the grinding wheel of different sizes is changed to match the wafers of different sizes, and the wafer support table still moves from the loading station to the grinding position according to the original stroke, the axis of the wafer support table that moves to the grinding position will be offset relative to the outer edge of the grinding wheel. That is, the axis of the wafer support table that moves to the grinding position is located inside or outside the outer edge of the grinding wheel. This will cause the wafer to be missed or over-grinded when the grinding wheel grinds the wafer. At the same time, the width of the protrusion formed after the wafer is ground does not meet the requirements.

[0004] Therefore, in related technologies, after the grinding wheel of the wafer grinding machine is replaced, the operator needs to repeatedly adjust the stroke of the wafer support table so that the axis of the wafer support table that moves to the grinding position is tangent to the outer edge of the grinding wheel. The process of repeatedly adjusting the stroke of the wafer support table is tedious, time-consuming and labor-intensive, and affects production efficiency. Summary of the Invention

[0005] In view of the shortcomings of the above-mentioned related technologies, the purpose of this application is to provide a wafer grinding method and a wafer grinding machine to solve the problem that when the grinding wheel of the wafer grinding machine is changed, the operator needs to repeatedly adjust the stroke of the wafer bearing table. The process of repeatedly adjusting the stroke of the wafer bearing table is cumbersome, time-consuming and labor-intensive, which affects the production efficiency.

[0006] To achieve the above and other related objectives, a first aspect of this application provides a wafer grinding method using a grinding machine. The grinding machine includes a wafer support stage for holding a wafer to be ground and a grinding wheel for performing grinding operations on the wafer. The wafer grinding method includes the following steps: based on the coordinate data of the wafer support stage and the specification data of the grinding wheel, controlling the wafer support stage to move relative to the grinding wheel to a position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel; the diameter of the grinding wheel is smaller than the radius of the wafer; and causing the grinding wheel to contact the surface of the wafer to be ground, driving the grinding wheel and / or the wafer support stage to rotate relative to each other to perform grinding operations on the wafer, so as to form an annular region on the edge of the wafer that is thicker than the surface to be ground, wherein the width of the annular region is the difference between the radius of the wafer and the diameter of the grinding wheel.

[0007] A second aspect of this application provides a wafer grinding machine, comprising: a base with loading / unloading stations and a processing station; a wafer support table disposed on the base and capable of reciprocating between the loading / unloading stations and the processing station for supporting wafers to be ground; a grinding mechanism disposed on the base, including a spindle, a grinding wheel detachably mounted on the end of the spindle, and a drive module for driving the spindle to move up and down at the processing station, wherein the axis of the grinding wheel coincides with the axis of the spindle; the diameter of the grinding wheel is smaller than the radius of the wafer; and a control device. When a grinding operation command is received, the device controls the wafer support to move relative to the grinding wheel to a position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, based on the coordinate data of the wafer support and the specification data of the grinding wheel. The device then contacts the surface of the wafer to be ground, drives the grinding wheel and / or the wafer support to rotate relative to each other to perform grinding operations on the wafer, thereby forming a thicker annular region on the edge of the wafer relative to the surface to be ground. The width of the annular region is the difference between the radius of the wafer and the diameter of the grinding wheel.

[0008] In summary, the wafer grinding method and wafer grinding machine provided in this application control the movement of the wafer support stage relative to the grinding wheel to a position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, and cause the grinding wheel to contact the surface of the wafer to be ground. This drives the grinding wheel and / or the wafer support stage to rotate relative to each other to perform grinding operations on the wafer, thereby forming a thicker annular region on the edge of the wafer relative to the surface to be ground. Thus, when grinding wafers of different sizes based on the TAIKO grinding process, after changing the grinding wheel on the wafer grinding machine, the operator can avoid repeatedly adjusting or calibrating the stroke of the wafer support stage, thereby simplifying the production process and improving production efficiency. Attached Figure Description

[0009] The specific features involved in this application are shown in the appended claims. A better understanding of the features and advantages of the invention can be achieved by referring to the exemplary embodiments and accompanying drawings described in detail below. A brief description of the drawings is as follows:

[0010] Figure 1 The diagram shown is a structural schematic of a single-station wafer grinding machine in one embodiment of this application.

[0011] Figure 2 The diagram shown is a schematic of a chip being mounted on a suction cup via an adapter plate in one embodiment of this application.

[0012] Figure 3 The diagram shows a positional schematic of a measuring mechanism used to detect the height of a wafer in one embodiment of this application.

[0013] Figure 4 This is a schematic diagram illustrating wafer top surface measurement using a first measurement component in one embodiment of this application.

[0014] Figure 5 This image shows a cross-sectional view of the suction cup in one embodiment of the present application.

[0015] Figure 6 This is a top view showing that, in one embodiment of this application, the through hole in the top plate of the suction cup is a circular hole.

[0016] Figure 7 This is a top view showing that, in one embodiment of this application, the through hole on the top plate of the suction cup is a square hole.

[0017] Figure 8 The diagram shown is an exploded view of the correspondence between the substrate stage and the film holder in one embodiment of this application.

[0018] Figure 9 The image shown is a cross-sectional view of the substrate stage and film holder in one embodiment of this application.

[0019] Figure 10 Displayed as Figure 9 A magnified view of the area at F1.

[0020] Figure 11 and Figure 12 The diagrams shown are schematic representations of the adapter structure in different embodiments of this application.

[0021] Figure 13 The diagram shown is a schematic representation of a main shaft mounted on an adjustment structure in one embodiment of this application.

[0022] Figure 14 The diagram shown is a structural schematic of the adjustment plate in one embodiment of this application.

[0023] Figure 15The diagram shown is a schematic representation of an embodiment of this application in which the outer edge of the projection circle of the grinding wheel is tangent to the axis of the wafer.

[0024] Figure 16 The diagram shown is a structural schematic of a multi-station wafer grinding machine in one embodiment of this application.

[0025] Figure 17 The flowchart shown is a wafer grinding method of a grinding machine according to one embodiment of this application.

[0026] Figure 18 The flowchart shown is a specific step of step S110 in one embodiment of this application.

[0027] Figure 19a and Figure 19b The images show schematic diagrams of the wafer support stage before it moves toward the grinding wheel and when it moves to the point where the wafer axis is tangent to the outer edge of the projection circle of the grinding wheel, respectively, in one embodiment of this application.

[0028] Figure 20a and Figure 20b The images show schematic diagrams of the states when the wafer stage moves to the working position and when the grinding wheel moves to the point where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, respectively, in one embodiment of this application.

[0029] Figures 21a to 21c The diagrams show the states of the support table in one embodiment of this application when it is at the loading station, during the movement of the support table, and when the grinding wheel moves to the working position.

[0030] Figure 22a and Figure 22b The images show schematic diagrams of the states when the wafer stage moves to the working position and when the grinding wheel moves to the point where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, respectively, in one embodiment of this application. Detailed Implementation

[0031] The following specific embodiments illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification.

[0032] In the following description, reference is made to the accompanying drawings, which illustrate several embodiments of the present application. It should be understood that other embodiments may also be used, and changes in mechanical composition, structure, electrical, and operation may be made without departing from the spirit and scope of this disclosure. The following detailed description should not be considered limiting, and the scope of the embodiments of the present application is defined only by the claims of the published patents. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the present application. Spatially related terms, such as “upper,” “lower,” “left,” “right,” “below,” “below,” “lower part,” “above,” “upper part,” etc., may be used herein to illustrate the relationship between one element or feature shown in the figures and another element or feature.

[0033] While the terms first, second, etc., are used in some instances herein to describe various elements or parameters, these elements or parameters should not be limited by these terms. These terms are used only to distinguish one element or parameter from another. For example, a first measuring component may be referred to as a second measuring component, and similarly, a second measuring component may be referred to as a first measuring component, without departing from the scope of the various described embodiments. Both the first measuring component and the second measuring component describe a measuring component, but they are not the same measuring component unless the context otherwise clearly indicates otherwise.

[0034] Furthermore, as used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context indicates otherwise. It should be further understood that the terms “comprising,” “including,” indicate the presence of the stated feature, step, operation, element, component, item, kind, and / or group, but do not preclude the presence, occurrence, or addition of one or more other features, steps, operations, elements, components, items, kinds, and / or groups. The terms “or” and “and / or” as used herein are to be interpreted inclusively, or mean any one or any combination thereof. Thus, “A, B, or C” or “A, B, and / or C” means “any one of: A; B; C; A and B; A and C; B and C; A, B, and C.” Exceptions to this definition occur only when combinations of elements, functions, steps, or operations are inherently mutually exclusive in some way.

[0035] The present application will be further described in detail below with reference to the accompanying drawings and specific embodiments. The technical solutions in the embodiments of the present application are clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, not all of them. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present application. The terms "an embodiment," "implementation," or similar wording used throughout this specification mean that a specific feature, structure, or characteristic described together with an implementation is included in at least one embodiment of the present application. Therefore, throughout the entire specification, the phrases "in an embodiment," "in an implementation," and similar wording may (but do not necessarily) refer to the same implementation.

[0036] As described in the background section, when grinding wafers of different sizes using the TAIKO grinding process, it is necessary to change the grinding wheel to a different size for each wafer. That is, after placing wafers of different sizes on the wafer carrier, a matching grinding wheel is used based on the size of the wafer on the carrier. However, if only the grinding wheel is changed to fit the different wafer sizes, and the wafer carrier still moves from the loading position to the grinding position according to its original stroke, the axis of the wafer carrier at the grinding position will be offset relative to the outer edge of the grinding wheel. In other words, the axis of the wafer carrier at the grinding position will either be located inside or outside the outer edge of the grinding wheel, resulting in either missed or over-grinding on the wafer during grinding. For example, if a larger grinding wheel is used, the axis of the stage moving to the grinding position will be located inside the outer edge of the grinding wheel, causing over-grinding of the wafer's center. Conversely, if a smaller grinding wheel is used, the axis of the stage moving to the grinding position will be located outside the outer edge of the grinding wheel, resulting in the wafer's center not being ground, i.e., missed grinding of the wafer's center. Both over-grinding and missed grinding will cause a center spot on the wafer, resulting in a wafer that does not meet requirements. Furthermore, the offset of the stage's axis relative to the outer edge of the grinding wheel will also cause the width of the protrusion formed after grinding to be insufficient.

[0037] Therefore, a common practice is for staff to repeatedly adjust or calibrate the travel of the wafer support table after changing the grinding wheel on the wafer grinding machine, so that the axis of the wafer support table moving to the grinding position can be tangent to the outer edge of the grinding wheel. However, the process of repeatedly adjusting the travel of the wafer support table is cumbersome, time-consuming and labor-intensive, which in turn affects production efficiency.

[0038] In view of this, some embodiments provided in this application disclose a wafer grinding method and a wafer grinding machine. By controlling the wafer support stage to move relative to the grinding wheel to a position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, and causing the grinding wheel to contact the surface of the wafer to be ground, the grinding wheel and / or the wafer support stage are driven to rotate relative to each other to perform grinding operations on the wafer, so as to form an annular region on the edge of the wafer that is thicker than the surface to be ground. In this way, when grinding wafers of different sizes based on the TAIKO grinding process, after changing the grinding wheel of the wafer grinding machine, the operator can avoid repeatedly adjusting and calibrating the stroke of the wafer support stage.

[0039] The wafer backthinning machine (hereinafter referred to as the backthinning machine) is a semiconductor processing equipment that uses grinding wheels to perform backthinning operations on the back side of a wafer. That is, the wafer backthinning machine can perform backthinning processing on the wafer (also called a wafer). In some embodiments, the backthinning machine can also be called a grinding machine or a thinning machine. After the wafer thickness is reduced using the backthinning machine, it is easier to use the wafer to fabricate more complex integrated circuits, and it can reduce the packaging height, reduce the chip packaging volume, and improve the chip's thermal diffusion efficiency, electrical performance, and mechanical performance. Furthermore, the wafer backthinning machine can also polish the wafer during the backthinning operation. In different embodiments, the wafer backthinning machine can be a single-station backthinning machine, a dual-station backthinning machine, or a multi-station backthinning machine. This application does not limit the detailed structure of the wafer backthinning machine, as long as the wafer support stage in the wafer backthinning machine can move relative to the grinding wheels and / or the grinding wheels can move relative to the wafer support stage. In some embodiments of this application, the wafer can also be referred to as a wafer.

[0040] In one embodiment, please refer to Figure 1 The figure shows a schematic diagram of a single-station wafer grinding machine in one embodiment of this application. As shown in the figure, the wafer grinding machine includes: a base 1, a wafer support 2, a grinding mechanism 3, and a control device (not shown in the figure).

[0041] The base 1 is used to support the plate support stage 2, and further, as... Figure 1 As shown, the base 1 also supports the grinding mechanism 3. The base 1 is equipped with a loading station, a unloading station, and a processing station. The loading station is where the wafer support table 2 holds the wafer; the unloading station is where the grinding machine removes the ground wafer from the wafer support table 2; and the processing station is where the wafer is ground by the grinding mechanism 3. The loading station and the unloading station can be in the same location or in different locations. For example, in… Figure 1 In the embodiment shown, the loading station and the unloading station can be in the same location.

[0042] The plate receiving platform 2 is mounted on the machine base 1 and can reciprocate between the loading / unloading station and the processing station.

[0043] In one example, the receiving platform 2 reciprocates along a straight line between the loading / unloading station and the processing station. For example, as... Figure 1 As shown, in a single-station grinding machine, the support table 2 and the grinding mechanism 3 are arranged on the same straight line. The support table 2 and the grinding mechanism 3, located at the loading position, are spaced apart or arranged at intervals in the horizontal direction. The loading station and the unloading station in the single-station grinding machine are in the same position. The support table 2 is located at the loading station (e.g., Figure 1 After the wafer support platform 2 (located at its position) carries the wafer to be ground, it moves along the direction shown by X in the figure to the processing station. At the processing station, the wafer to be ground is ground by the grinding mechanism 3. Then, the wafer support platform 2 carries the ground wafer and moves along the opposite direction of X in the figure to the unloading station, so that the grinding machine can remove the ground wafer. After the ground wafer is removed, the wafer support platform continues to load wafers at its current position. In other embodiments, the wafer support platform can also reciprocate along a curve between the unloading / loading station and the processing station, for example, the wafer support platform reciprocates along a circular curve (e.g., a multi-station grinding machine).

[0044] One wafer stage 2 can hold one or more wafers. In one embodiment, when one wafer is held on the wafer stage 2, the wafer and the wafer stage 2 are coaxial. That is, the axis of the wafer is the intersection of the wafer's axis when it rotates and the wafer's axis of rotation, and the axis of the wafer stage is the intersection of the wafer stage's axis when it rotates and the wafer stage's axis of rotation. When the wafer is placed on the wafer stage, their axes coincide. The axis of the wafer is a straight line passing through the center of the wafer and perpendicular to it. Similarly, the axis of the wafer stage is a straight line passing through the center of the wafer stage and perpendicular to it.

[0045] In another embodiment, the wafer support stage carries multiple wafers, which are distributed around the center of the wafer support stage and are equidistant from the center of the stage. When multiple wafers are carried on the wafer support stage, the wafer grinding machine performs a grinding operation, and the wafer support stage 2 causes the wafers to rotate sequentially at the processing station for thinning.

[0046] The wafer can be placed on a suction cup on the wafer support stage. For example, the wafer support stage is provided with a suction cup for adsorbing and fixing the wafer, the axis of the suction cup coincides with the axis of the wafer support stage, wherein the axis of the suction cup is a straight line passing through the center of the suction cup and perpendicular to the suction cup. The suction cup is a vacuum suction cup, and the wafer is directly adsorbed onto the suction cup of the wafer support stage. Alternatively, the wafer can be directly attached to a film holder on the wafer support stage, which will be described in detail later.

[0047] In actual grinding operations, there are situations where some wafers cannot be directly picked up by the chuck of the wafer stage. For example, the suction holes on the upper surface of the chuck used for processing 12-inch wafers may be located at the edge of the chuck. However, for 4-8 inch wafers, this type of chuck will not be able to pick up and fix the wafer, and therefore subsequent processing is not possible.

[0048] Therefore, this application proposes an adapter board in some embodiments. Please refer to... Figure 2 The figure shows a schematic diagram of a wafer being mounted on a suction cup via an adapter plate in one embodiment of this application. As shown, the wafer 4 is attached to the adapter plate 21, and the size of the adapter plate 21 is such that it can be adsorbed and fixed by the suction cup 20 on the wafer support stage. Specifically, the wafer 4 attached to the adapter plate 21 is placed on the suction cup 20 of the wafer support stage and fixed by vacuum adsorption. By attaching the wafer to the adapter plate, which is sized to be adsorbed by the suction cup 20, the problem of wafers of different specifications not being adsorbed by the suction cup 20 is solved. By adsorbing the adapter plate by the suction cup 20, the wafer 4 is fixed on the suction cup 20, providing the basic conditions for wafer processing. Without changing the existing structure of the equipment, wafers of different sizes and shapes can be processed.

[0049] In specific implementations, the adapter plate can attach one or more wafers. During actual processing, the size of the adapter plate 21 is such that it covers the suction holes on the suction cup 20 when placed on it. When attaching the wafer 4 to the adapter plate 21, adhesive can be applied to the wafer 4 before attaching it to the adapter plate 21; in this case, the adapter plate 21 may not have an adhesive layer. Furthermore, the top surface of the adapter plate 21 also has an adhesive layer 210, allowing the wafer 4 to be directly adhered to the adhesive layer 210.

[0050] In one embodiment, the wafer grinding machine further includes a measuring mechanism for measuring wafer thickness. See also... Figure 3 and Figure 4 , Figure 3 This is a schematic diagram showing the position of the wafer height detected by a measuring mechanism in one embodiment of this application. Figure 4The figure shows a schematic diagram of wafer top surface measurement performed by a first measuring component in one embodiment of this application. As shown, the wafer grinding machine also includes a measuring mechanism 22 for measuring wafer thickness. When the control device determines whether the thickness of the wafer in the grinding operation has reached the target value, it does so based on the top surface height of the wafer measured by the measuring component of the measuring mechanism 22 and the determined reference height of the top surface of the adapter plate.

[0051] exist Figure 3 In the illustrated embodiment, the measuring mechanism 22 includes a first measuring component 221 and a second measuring component 220. During the grinding operation on the wafer 4, the first measuring component 221 measures the top surface height of the wafer 4 in real time, while the second measuring component 220 does not contact the top surface of the adapter plate 21. Specifically, when the wafer 4 is being ground, the first measuring component 221 measures the top surface height of the wafer 4 in real time; that is, the value measured by the first measuring component 221 changes in real time. The second measuring component 220 does not contact the top surface of the adapter plate 21. The thickness of the wafer 4 can be determined based on the difference between the real-time value measured by the first measuring component 221 and the pre-measured reference height of the top surface of the adapter plate by the second measuring component 220.

[0052] In this embodiment, the first measuring component 221 and the second measuring component 220 have the same structure and are mounted on a lifting mechanism 222 that drives them to move up and down. Both the first measuring component 221 and the second measuring component 220 include a contact measuring instrument or a known contact displacement sensor. The contact measuring instrument is connected to a horizontally extending measuring rod. The inner end of the measuring rod connected to the contact measuring instrument can rotate relative to the contact measuring instrument. After adjusting the position of the measuring rod, the measuring rod and the contact measuring instrument can be fixed by nuts and bolts. The outer end of the measuring rod is provided with a probe extending along the height direction. The probe is height-adjustably mounted on the measuring rod and can be threaded to the measuring rod or fixed by a set screw.

[0053] This application, by using an adapter plate with an adhesive layer on its top surface, measures the height of the wafer's top surface using a first measuring component. This height, combined with a pre-determined reference height of the adapter plate's top surface, is then used to calculate the wafer thickness. This eliminates the need for the second measuring component to maintain contact with the adapter plate during the thinning process, thus changing the conventional height measurement method and effectively ensuring the safety of the measuring mechanism. Furthermore, by limiting the reference height of the adapter plate's top surface, this application helps ensure the accuracy of the calculations.

[0054] In the following text, the contact measuring instrument, measuring rod, and probe of the first measuring component 221 are defined as the first contact measuring instrument 2210, the first measuring rod 2211, and the first probe 2212; and the contact measuring instrument, measuring rod, and probe of the second measuring component 220 are defined as the second contact measuring instrument 2200, the second measuring rod 2201, and the second probe 2202. The contact measuring instrument is connected to the control device, for example, through a connected controller (PLC) and an industrial control computer.

[0055] In one embodiment, with the bottoms of the first probe 2212 of the first measuring component 221 and the second probe 2202 of the second measuring component 220 flush, both the first measuring component 221 and the second measuring component 220 are moved down to the measuring position so that the first probe 2212 abuts against the top surface of the wafer 4 and the second probe 2202 abuts against the top surface of the adapter plate 21 outside the wafer 4. The measured value of the second measuring component 220 at this time is determined and stored as the reference height of the top surface of the adapter plate.

[0056] The first probe of the measuring mechanism of this application can move horizontally, thereby effectively adapting to the height measurement needs of wafers of different positions and sizes, improving the flexibility and applicability of the measurement.

[0057] In one specific embodiment, the process of detecting whether the wafer thickness has reached the target value through the measuring mechanism 22 is as follows: After obtaining the reference height of the top surface of the adapter plate 21 in the above manner, the second probe 2202 or the second probe rod 2201 is removed from the second measuring component 220; or the second probe 2202 is adjusted to a predetermined height to avoid contact between the second probe 2202 and the top surface of the adapter plate 21 during the grinding operation of the wafer 4. Then, before the suction cup 20 rotates, the lifting mechanism 222 drives the first measuring component 221 to move down to the measuring position. At this time, the first probe 2212 abuts against the top surface of the wafer 40 and is close to the center of the wafer 4. Next, the suction cup 20 is rotated, and at the same time, the grinding wheel of the grinding mechanism 3 moves to the thinning position for thinning. The thickness of the wafer 4 is determined according to the reference height of the top surface of the adapter plate 21 and the value measured in real time by the first measuring component 221. After determining that the thickness of the wafer 4 has reached the target value, the thinning / grinding operation is stopped. When measuring a rotating wafer, this application places the first probe close to the center of the wafer, which can effectively reduce the relative movement of the first probe on the wafer during wafer rotation, thus improving the safety of the measurement.

[0058] In one embodiment, the adapter plate 21 is attached with a plurality of evenly spaced wafers 4, which are distributed around the center of the suction cup 20. When a wafer 4 rotates to the outside of the grinding wheel, the top surface height of the wafer 4 is measured by the first measuring component 221. Then, based on the same principle described above, it is determined whether the thickness of the wafer 4 has reached the target value. After the measurement is completed, the lifting mechanism 222 drives the first measuring component 221 and the second measuring component 220 to reset, awaiting the next measurement.

[0059] In one embodiment, the grinding wheel is controlled to move downward to thin a wafer 4 attached to the adapter plate 21. After the grinding wheel moves the theoretical downward stroke, the grinding wheel stops moving downward, and the actual thickness of the wafer 4 at this time is measured. The actual thickness is compared with the target value. Usually, due to the wear of the grinding wheel, the actual thickness is greater than the target value. Therefore, the wear amount of one thinning is determined by subtracting the target value from the actual thickness. In subsequent processing, after processing each wafer 4, the total wear amount is increased by one wear amount. When the total wear amount is determined to reach the plate replacement threshold, a signal to replace the grinding wheel is issued. This application can automatically perform high-precision calculation of the wear amount of the grinding wheel after each thinning, which can effectively ensure accurate and timely replacement of the grinding wheel.

[0060] As mentioned earlier, during actual grinding operations, some wafers cannot be directly adsorbed by the wafer holder. Therefore, in related technologies, to accommodate wafers of different shapes and sizes, it is usually necessary to set up various sizes of chucks to adsorb wafers of different dimensions. This results in high chuck costs, requires manual replacement of chucks, and each chuck can only hold one wafer at a time, leading to poor flexibility in practical applications.

[0061] To address the above issues, please refer to the following embodiments: Figure 5 The figure shows a cross-sectional view of a suction cup in one embodiment of the present application. As shown, the suction cup 20 includes a base plate 200 and a top plate 201 adapted to the base plate 200. The top plate includes top plates 201 of different specifications. The base plate 200 can be detachably and sealedly connected to any of the top plates 201 of different specifications.

[0062] In one embodiment, the top plate 201 has a countersunk hole, and the bottom plate 200 has a screw hole corresponding to the countersunk hole. The top plate 201 and the bottom plate 200 are connected by a fastening screw 203 located in the countersunk hole. Simultaneously, to ensure the sealing between the bottom plate 200 and the top plate 201, thereby ensuring the stability of vacuum adsorption, a sealing groove is formed on the surface of the bottom plate 200 facing the top plate 201, surrounding the through hole 2010. A first sealing ring 204 is provided in the sealing groove. In this embodiment, the sealing ring facilitates the replacement of the top plate and ensures airtightness. Of course, the surface of the top plate 201 facing the bottom plate 200 can also have a groove corresponding to the sealing groove.

[0063] In other embodiments, the top plate 201 can also be bonded to the top plate 201 using known removable adhesive, which makes it relatively easy to replace the top plate 201, while the removable adhesive can achieve a seal.

[0064] Please continue reading. Figure 5 Each of the top plates 201 has at least one through hole 2010, and the shape of the through holes 2010 on different top plates 201 is different. When any size of top plate 201 is sealed to bottom plate 200, each through hole 2010 on the top plate 201 and bottom plate 200 form a workpiece limiting groove 202. An adsorption hole 2002 located in the through hole 2010 is formed on the surface of bottom plate 200 facing the top plate 201. The adsorption hole 2002 communicates with the inner cavity of bottom plate 200. An air extraction port 2001 communicating with the inner cavity is provided on the side of bottom plate 200. A quick connector 2000 is threadedly connected to the air extraction port 2001.

[0065] The top plate 201 can be any feasible shape, such as circular or square. There can be only one through-hole 2010 on the top plate 201, concentric with the top plate 201. In one example, there can also be multiple through-holes 2010 on the top plate 201, evenly distributed around the circumference; for example, there can be 2-6 through-holes. The number of top plates 201 can be designed according to the shape and size of the wafer to be processed. For example, if the wafer to be processed includes circular, rectangular, square, and regular hexagonal shapes, then the number of top plates 201 is 4.

[0066] The shape of the through-hole 2010 on the top plate 201 matches the shape and size of a wafer. (See also...) Figure 6 and Figure 7 , Figure 6 This is a top view showing that, in one embodiment of this application, the through hole on the top plate of the suction cup is a circular hole. Figure 7The figure shows a top view of the suction cup top plate in one embodiment of this application, where the through hole 2010 is square. The through hole 2010 can be either circular or square, depending on the shape and size of the wafer. Figure 7 As shown, when the through-hole 2010 is a polygonal hole, a buffer sheet 206 is provided at each apex corner of the hole wall. The buffer sheet 206 can be a silicone film attached to the hole wall, or other feasible materials, which are not limited here. The buffer sheet 206 can effectively protect the apex corners of the polygonal wafer and improve safety.

[0067] The inner cavity may be multiple and correspond one-to-one with the workpiece limiting groove, with each inner cavity connected to an air extraction port; or, the inner cavity may be one and connected to multiple workpiece limiting grooves. Figure 5 As shown, the inner cavity is one and is connected to multiple workpiece limiting grooves 202. At this time, the inner cavity is coaxially arranged with the base plate 200.

[0068] In one embodiment, the shape of the base plate 200 is concentric with that of the top plate 201.

[0069] In one embodiment, the base plate includes a first plate and a second plate, which are sealed together. The opposing surfaces of the first and second plates are provided with matching grooves, which constitute the inner cavity. In another embodiment, the first plate 2011 and the second plate 2012 are sealed together by a sealant, which is adhered to the edges of the first plate 2011 and the second plate 2012.

[0070] In another embodiment, as shown in the appendix Figure 5 As shown, the first plate 2011 and the second plate 2012 are connected by a second screw (not shown in the figure), and the first plate 2011 and the second plate 2012 are sealed by a second sealing ring 205.

[0071] In another embodiment, there are multiple grooves 2013 on the first plate and the second plate, each corresponding to a workpiece limiting groove 202. Each inner cavity formed by the groove is connected to an air extraction port 2001. This structure makes it easier to ensure the negative pressure effect of each workpiece limiting groove 202.

[0072] In summary, the chuck in this application includes a detachable top plate and a bottom plate. The top plate has through-holes, allowing for the processing of wafers of different shapes and sizes without replacing the entire chuck; only the top plate needs to be replaced. This enables the use of multiple top plates to work with a single bottom plate, significantly reducing the cost of the chuck. Furthermore, the top plate can have multiple through-holes, allowing for the simultaneous attachment of multiple wafers to the chuck, providing greater application flexibility. Additionally, the bottom plate in this application is assembled from two plates, facilitating plate processing and the formation of internal cavities, making it easier to implement. The use of a sealing ring effectively ensures a tight seal, and the screw connection makes disassembly and assembly easier. Moreover, if one plate malfunctions, the entire chuck does not need to be replaced.

[0073] Wafers are typically placed on a wafer carrier stage using a wafer holder. Specifically, the wafer holder is a ring-shaped support on which a thin film is bonded. The wafer is bonded to the thin film and located in the central area of ​​the ring-shaped support. Once the wafer holder is placed on the wafer carrier stage, the wafer is positioned simply by fixing the wafer holder. In existing technology, the structure for fixing the wafer holder on the wafer carrier stage is generally a ring-shaped edge fastening ring. Specifically, the edge fastening ring includes a clamp and a pressure ring. The clamp is fixedly connected to the wafer carrier stage, and the pressure ring is located on top of the clamp and coaxially arranged with the clamp. The inner diameter of the clamp is equal to the outer diameter of the wafer holder, allowing the clamp to fit around the outer circumference of the wafer holder. The distance between the inner side of the pressure ring and the inner side of the clamp is less than the width of the wafer holder, allowing the pressure ring to cover the top of the wafer holder. Multiple screws evenly arranged circumferentially around the pressure ring are installed on top of the pressure ring to fix the pressure ring and the clamp together, thereby locking the wafer holder onto the wafer carrier stage.

[0074] In actual operation, the process of removing the film holder from the substrate and placing and locking it onto the substrate requires the removal and installation of multiple screws. The entire process is cumbersome, time-consuming, and labor-intensive, which leads to low working efficiency of the grinding machine. Moreover, after the screws are removed, the multiple screws are scattered, which can easily cause parts to be lost.

[0075] Therefore, in one embodiment of the wafer stage of this application, the process of removing the wafer holder from the wafer stage and placing and locking the wafer holder onto the wafer stage can be simplified, saving time and effort, thereby improving the working efficiency of the wafer grinding machine (wafer thinning machine) and avoiding the loss of parts.

[0076] In one embodiment, the wafer is disposed on the membrane holder. See also... Figure 8 The figure shows an exploded view of the correspondence between the wafer support stage and the film holder in one embodiment of this application. As shown in the figure, the wafer support stage 2 is provided with a film holder 23, and the film holder 23 is provided with a thin film for bonding the wafer.

[0077] exist Figure 8In the embodiment shown, the support stage includes a stage 24 and a fixing mechanism 25.

[0078] The stage 24 is used to support and adsorb the thin film. When the thin film is supported on the stage 24, the wafer bonded to the thin film is coaxial with the stage 24. The wafer support stage can rotate around the axis of the stage, that is, the wafer support stage can rotate around the axis of the stage 24, thereby driving the wafer to rotate, thereby realizing the polishing or thinning of the wafer.

[0079] The fixing mechanism 25 includes a first bracket 250 sleeved around the outer periphery of the platform 24, a second bracket 251 sleeved around the outer periphery of the first bracket 250, and a locking member 254 for locking the first bracket 250 and the second bracket 251. The second bracket 251 is provided with a pressure plate 2510 for pressing against the membrane frame 23. When the locking member 254 is in a first working position, it applies a pressing force to the corresponding position on the second bracket 251 so that the pressure plate 2510 presses against the membrane frame 23. When the locking member 254 is in a second working position, it releases the pressing force applied to the second bracket 251.

[0080] In this embodiment, when the locking member 254 is in the first working position, it applies a clamping force to the corresponding position on the second bracket 251, including a first clamping force and a second clamping force. The first clamping force is vertically downward, so that the pressure plate 2510 presses against the film frame 23, that is, the film frame 23 can be pressed and confined between the pressure plate 2510 and the first bracket 250. The second clamping force is horizontal, pointing from the first bracket 250 to the second bracket 251. Specifically, when all the locking members 254 respectively disposed on both sides of the first support 250 along the radial direction of the stage 24 apply a second clamping force to the second support 251, the second support 251 can be tightened, thereby fixing the second support 251 in the horizontal direction. When all the locking members 254 apply a first clamping force to the second support 251, the second support 251 can be pressed and limited between the locking members 254 and the second bearing surface 25010 of the first support 250, thereby fixing the second support 251 in the vertical direction. The pressure plate 2510 can press the film holder 23 in the vertical direction when the second support 251 is fixed, thereby fixing the film holder 23 by fixing the fixed second support 251, and thus fixing the wafer onto the stage 24.

[0081] In this embodiment, when the locking member 254 is in the second working position, the locking member 254 releases the first and second clamping forces applied to the second bracket 251, thereby releasing the fixation on the second bracket 251. This allows the operator to remove the second bracket 251 from the first bracket 250, thus enabling the removal of the wafer holder 23. Based on the above, in this embodiment, simply switching the working position of the locking member 254 is sufficient to remove the wafer holder 23 from the wafer support platform or place and lock it onto the wafer support platform, simplifying the process and saving time and effort, thereby improving the working efficiency of the wafer grinding machine. Furthermore, in this embodiment, there is no need to disassemble or assemble multiple screws. The locking member 254, used to remove the wafer holder 23 from the wafer support platform or place and lock it onto the wafer support platform, is installed on the first bracket 250. This means the locking member 254 is never disassembled, thus preventing part loss.

[0082] In one embodiment, the first support 250 includes a first annular portion 2500 and a second annular portion 2501. The second annular portion 2501 is located on the side of the first annular portion 2500 away from the stage 24. The upper surface of the first annular portion 2500 is higher than the upper surface of the second annular portion 2501. The upper surface of the first annular portion 2500 forms a first bearing surface 25000, and the upper surface of the second annular portion 2501 forms a second bearing surface 25010. The film frame 23 can be supported on the first bearing surface 25000. The second support 251 is annular and can be placed on the second bearing surface 25010. The locking member 254 installed on the first support 250 can fix the second support 251, and the pressure plate 2510 is pressed down by the second support 251 so that the pressure plate 2510 can press against the film frame 23, thereby fixing the film frame 23. Once the wafer has been thinned, the locking member 254 can release the second support 251, allowing the operator to remove the second support 251 from the first support 250, thereby removing the membrane holder 23.

[0083] Further, in this embodiment, the second support 251 is sleeved on the outer periphery of the first support 250 and the membrane frame 23. The first support 250 is provided with a positioning part 2502 for positioning the membrane frame 23. The positioning part 2502 is disposed on the first bearing surface 25000 and is configured to position the membrane frame 23, thereby ensuring that the position of the membrane frame 23 after being placed on the first bearing surface 25000 meets the requirements. The positioning part 2502 is disposed on the upper surface of the first annular part 2500, and a first positioning surface 25020 is formed on the side of the positioning part 2502 facing the platform 24. The first positioning surface 25020 is parallel to the axis of the platform 24. A second positioning surface 230 is formed on the outer side of the membrane frame 23. The first positioning surface 25020 can fit against the second positioning surface 230, thereby positioning the membrane frame 23 circumferentially. The positioning part 2502 and the second support 251 work together to achieve accurate positioning of the membrane frame 23.

[0084] In one embodiment, the second support 251 is provided with two or more pressure plates 2510, which are evenly arranged around the axis of the platform 24, thereby pressing the film frame 23 at different positions along its circumference, thereby further stabilizing the film frame 23.

[0085] In one embodiment, please refer to Figure 9 and Figure 10 , Figure 9 The image shown is a cross-sectional view of the substrate stage and film holder in one embodiment of this application. Figure 10 Displayed as Figure 9 The enlarged view at point F1 shows that the locking member 254 includes a wedge 2540 that can radially pass through the first bracket 250 to extend into the second bracket 251, and a drive part 2541 that drives the wedge 2540 to move radially along the platform.

[0086] In one embodiment, a groove 2511 is formed on the inner side of the second bracket 251, extending around the axis of the platform 24. A channel 2503 is formed on the first bracket 250 along the radial direction of the platform 24. A wedge 2540 is mounted on the first bracket 250 and can move radially along the platform 24 within the channel 2503 of the first bracket 250. The wedge 2540 is provided with an inclined surface 25400, so that the vertical height of the wedge 2540 gradually decreases from the side closer to the platform 24 to the side farther away from the platform 24. The wedge 2540 can move radially along the platform 24 within the channel 2503 until the side of the wedge 2540 away from the platform 24 can extend into the groove 2511, and the inclined surface 25400 can press against the edge of the groove 2511. When the edge is closed, the wedge 2540 can apply a first pressing force downward in the vertical direction and a second pressing force in the horizontal direction from the first support 250 to the second support 251. The driving part 2541 is configured to drive the wedge 2540 to move radially along the platform 24. That is, in this embodiment, the wedge 2540 can be moved radially away from or towards the platform 24 by the driving part 2541 to make the locking member 254 in the first working position or the second working position. The operation is simple, more time-saving and labor-saving, thereby further improving the working efficiency of the wafer thinning machine.

[0087] Furthermore, in this embodiment, the drive unit 2541 includes a stud 25410 and a first nut 25411. The stud 25410 extends radially along the platform 24 and passes through the first bracket 250. The portion of the stud 25410 extending into the inner side of the first bracket 250 is located within the channel 2503. The stud 25410 has a first thread (not shown in the figure) on the side away from the platform 24 along its axial direction. The wedge block 2540 is fixedly connected to the stud 25410 by the mounting plate 2542. The first nut 25411 is screwed onto the stud 25410 and abuts against the side of the first bracket 250 away from the platform 24. The operator only needs to turn the first nut 25411 to move the wedge block 2540 radially away from or towards the platform 24, thereby switching the working position of the locking member 254, which is simple to operate.

[0088] In this embodiment, the stud 25410 is provided with a second thread (not shown in the figure) on the side of its axial direction close to the platform 24. The drive part 2541 also includes a second nut 25412, which is screwed onto the stud 25410. The stud 25410 is provided with a protrusion 254100, which is located between the first thread and the second thread and protrudes radially from the stud 25410. The mounting plate 2542 is sleeved on the outer periphery of the stud 25410 and is pressed and limited between the protrusion 254100 and the second nut 25412, thereby fixing the wedge 2540 on the stud 25410 to ensure that the wedge 2540 can move together with the stud 25410.

[0089] It should be noted that, in actual operation, the operator needs to operate the first nuts 25411 of all the locking members 254 respectively set on both sides of the first bracket 250 along the radial direction of the platform 24 to rotate synchronously, so that the first nuts 25411 of all the locking members 254 respectively set on both sides of the first bracket 250 along the radial direction of the platform 24 apply a second clamping force to the second bracket 251, thereby tightening the second bracket 251.

[0090] Furthermore, the first bracket 250 is provided with a through hole 2504, through which the stud 25410 passes through the first bracket 250. The radial width of the protrusion 254100 along the stud 25410 is greater than the diameter of the through hole 2504, so that the side of the protrusion 254100 away from the platform 24 can abut against the first bracket 250, thereby limiting the stroke of the stud 25410.

[0091] Please continue reading. Figure 1 The grinding mechanism 3 is mounted on the machine base 1 and is used to contact the wafer located at the processing station to perform grinding operations on the entire wafer or a portion thereof. In one embodiment, the grinding mechanism 3 includes a spindle 32, a grinding wheel 30 detachably mounted on the end of the spindle 32, and a drive module 31 for driving the spindle 32 to move up and down at the processing station. The axis of the grinding wheel 30 coincides with the axis of the spindle 32, and the diameter of the grinding wheel 30 is smaller than the radius of the wafer. The axis of the grinding wheel 30 is a straight line passing through the center of the grinding wheel 30 and perpendicular to it. Similarly, the axis of the spindle 32 is a straight line passing through the center of the spindle 32 and perpendicular to it.

[0092] Specifically, such as Figure 1As shown, the wafer support stage 2, carrying the wafer, moves along the slide rail 10 located on the machine base 1 to the processing station. The drive module 31 drives the spindle 32 to descend, thereby causing the grinding wheel 30 to descend to the upper surface of the wafer. Then, the drive module 31 drives the spindle 32 to rotate, thereby driving the grinding wheel 30 to perform grinding operations to achieve overall or partial thinning or polishing of the wafer. After processing is completed, the drive module 31 drives the grinding wheel 30 to reset, and the wafer support stage 2, carrying the processed wafer, moves again along the guide rail to the loading and unloading station, so that the wafer grinding machine can remove the processed wafer from the wafer support stage 2. It should be noted that although this application describes the wafer support stage 2 moving along the slide rail 10 located on the machine base 1, it is not limited to this. The wafer support stage 2 can also be set on a conveyor belt or other mechanism that can move back and forth.

[0093] In one embodiment, the machine base 1 is provided with a lead screw assembly (not shown) for driving the plate support 2 toward the grinding wheel 30. The plate support 2 is slidably mounted on the machine base 1 via the lead screw assembly. The lead screw assembly can precisely control the displacement of the plate support 2, improving the movement accuracy of the plate support 2. Furthermore, the machine base 1 is provided with a stop assembly 11, which is used to limit the limit displacement of the plate support 2 when it moves along its movement path. For example, the machine base 1 is provided with two stop members 11, which are arranged opposite to each other on both sides of the slide rail 10 to limit the limit displacement of the plate support when it moves along its movement path, avoid positional deviation of the plate support, and further improve the displacement accuracy of the plate support.

[0094] like Figure 1 As shown, the drive module 31 includes a housing 310, a lifting drive (not shown), a rotary drive (not shown), and a support 311. The housing 310 is mounted on the base 1. The lifting drive is disposed within the housing 310. The support 311 supports the spindle 32. The spindle 32 is fixedly mounted on the support 311. The lifting drive drives the support 311 to slide vertically, thereby driving the spindle 32 to perform lifting operations. The rotary drive drives the grinding wheel 30 to rotate via the spindle 32, so that the grinding wheel 30 performs grinding operations on the wafer support stage 2.

[0095] In one embodiment, the support member 311 includes a slide plate 3110 and a locking ring 3111. The slide plate 3110 is slidably disposed on the housing 310, and the locking ring 3111 is fixed to the slide plate 3110. The main shaft 32 is installed in the locking ring 3111. Further, the grinding mechanism 3 also includes a first slide rail 312, which is vertically disposed on the housing 310, and the slide plate 3110 slides in cooperation with the first slide rail 312. The first slide rail 312 guides and limits the lifting and lowering movement of the slide plate 3110, improving the accuracy of the lifting and lowering displacement of the main shaft 32 and the grinding wheel 30.

[0096] like Figure 1 As shown, the grinding mechanism 3 also includes a balancing component 34. The balancing component 34 is mounted on the housing 310, and its output end is connected to the support member 311 and moves up and down synchronously with the support member 311 to pull the support member 311. By pulling the support member 311 through the balancing component 34, the sum of the weights of the support member 311, the spindle 32, and the grinding wheel 30 is approximately equal to the pulling force of the balancing component 34. This means the grinding wheel 30 can contact the wafer with zero gravity, preventing damage to the wafer due to pressure and improving wafer protection.

[0097] Further, in one embodiment, there are two balancing components 34, symmetrically arranged on both sides of the support member 311, so that the support member 311 is subjected to uniform traction force, thereby ensuring the levelness of the grinding wheel 30 and improving the processing quality of the grinding wheel 30. In one embodiment, the balancing component 34 includes a balancing bracket 340 and a cylinder 341. The first end of the balancing bracket 340 is fixedly installed on the top of the housing 310, and the second end of the balancing bracket 340 extends out of the housing 310 to form a cantilever structure. The cylinder seat of the cylinder 341 is pivotally mounted on the second end of the balancing bracket 340, and the piston rod of the cylinder 341 is connected to the locking ring 3111. The two cylinders 341 jointly pull / tighten the locking ring 3111 to balance the sum of the weights of the support member 311, the main shaft 32, and the grinding wheel 30. When the main shaft 32 and the grinding wheel 30 move up and down in a straight direction, the piston rod moves up and down synchronously to always maintain a taut state. In other embodiments, cylinder 341 may be replaced by a hydraulic cylinder or an electric actuator, etc., without specific limitations.

[0098] In one embodiment, the drive module of the grinding mechanism 3 further includes a drive mechanism capable of driving the spindle to move in the horizontal direction. This drive mechanism includes a drive member that drives the spindle to move in the front-to-back direction and / or a drive member that drives the spindle to move in the left-to-right direction. The drive member is, for example, a cylinder. It should be noted that in other embodiments, the drive mechanism can also be of other structures, as long as it can drive the spindle to move in the horizontal direction.

[0099] Since different sizes of wafers require different grinding wheel sizes, in one embodiment, the wafer grinding machine can replace the spindle 32 with different sized grinding wheels 30 according to the wafer size. Specifically, the grinding wheel 30 detachably mounted at the end of the spindle 32 can be of different specifications, and the spindle 32 is adapted to the specifications of the grinding wheel 30. Because the dimensions of the spindle 32 and the grinding wheel 30 can be flexibly adjusted according to actual processing needs, the diverse processing requirements of wafers are met, improving the versatility of the wafer grinding machine.

[0100] In one embodiment, such as Figure 1 As shown, the grinding mechanism also includes an adapter 33. The adapter 33 is mounted on the spindle 32, and grinding wheels 30 of different diameters are selectively mounted on it. The grinding wheels 30 are stably mounted to the spindle 32 via the adapter 33. Simultaneously, the adapter 33 has a certain degree of versatility, allowing for fixed mounting with grinding wheels 30 of different diameters, making the replacement of the grinding wheels 30 simple and easy, and improving replacement efficiency. It should be noted that when the spindle 32 needs to be replaced, the locking ring 3111 can be replaced accordingly.

[0101] Please see Figure 11 and Figure 12 The figures show schematic diagrams of the adapter components in different embodiments of this application. As shown, the adapter component 33 includes an adapter 330 and an adapter plate 331. The adapter 330 is disposed at the upper end of the adapter plate 331 and is mounted on the main shaft 32. The lower end of the adapter plate 331 has multiple coaxially arranged limiting annular grooves 3312. Grinding wheels 30 of different diameters are selectively installed in the corresponding limiting annular grooves 3312. The limiting annular grooves 3312 achieve limiting installation of the grinding wheels 30, improving the stability and installation efficiency of the grinding wheels 30.

[0102] Furthermore, in this embodiment, the adapter plate 331 includes a main plate body 3310 and multiple annular plates 3311 of different diameters. The multiple annular plates 3311 of different diameters are coaxially protruding from the lower end face of the main plate body 3310, and adjacent annular plates 3311 form corresponding limiting annular grooves 3312. The main plate body 3310 has multiple sets of mounting holes, each set including multiple mounting holes distributed circumferentially along the main plate body 3310. Each limiting annular groove 3312 has one set of mounting holes. When the grinding wheel 30 is engaged with the corresponding limiting annular groove 3312, it is also simultaneously fixedly connected to the main plate body 3310 through the mounting hole sets within the limiting annular groove 3312, further improving the stability and reliability of the grinding wheel 30's installation.

[0103] Therefore, the wafer grinding machine of this application can replace the spindle and grinding wheel of different diameters according to actual processing needs, so as to solve the problem that the wafer grinding machine cannot meet the processing needs of diverse or multi-specification wafers due to the single processing technology. This realizes the diversified processing technology of the grinding machine and thus improves its versatility.

[0104] During the grinding operation of the wafer, due to the required machining angle, the pitch and yaw angles of the spindle relative to the Z-axis (vertical direction) need to be adjusted so that the spindle can perform grinding operations on the wafer at a more suitable machining angle. That is, the grinding wheel can perform grinding operations on the wafer at a preset machining angle.

[0105] Currently, spindle adjustment structures typically employ a three-point leveling method. This involves a base plate, a fixed block, a leveling plate, and three adjusting screws. The base plate is fitted onto the spindle, and side plates surround the outside of the spindle. The spindle's yaw and pitch are adjusted via the three adjusting screws distributed around its outer perimeter. Because this type of spindle adjustment structure forms a ring-like structure that encloses the spindle, it is relatively large and heavy. Therefore, during prolonged operation, the spindle may experience significant displacement and deformation due to the weight of the adjustment structure, affecting the spindle's wafer thinning effect and potentially causing wafer breakage. Furthermore, during the wafer thinning process, the rotating disk holding the wafer exerts an upward force along the Z-axis on the spindle, causing spindle misalignment and compromising the spindle's positional accuracy relative to the wafer.

[0106] Please see Figure 13 The diagram shown is a schematic representation of one embodiment of this application, in which the main shaft is disposed on the adjustment structure. Figure 13 In the illustrated embodiment, the grinding mechanism 3 further includes an adjustment structure 35 for adjusting the pitch and yaw angles of the spindle 32 relative to the vertical. The adjustment structure 35 is disposed on the housing 310 described above. Specifically, the adjustment structure 35 includes a base plate 350 and an adjustment plate 351. The base plate 350 is disposed on the housing 310, and the adjustment plate 351 is disposed between the base plate 350 and the spindle 32 for connecting the spindle 32. The adjustment plate 351 changes the pitch angle of the spindle 32 relative to the vertical by generating partial elastic deformation in a first direction, and changes the yaw angle of the spindle 32 relative to the vertical by generating partial elastic deformation in a second direction. The first direction is the front-to-back direction, and the second direction is the left-to-right direction.

[0107] In one embodiment, please refer to Figure 13 and Figure 14 , Figure 14 The figure shows a schematic diagram of the structure of the adjustment plate in one embodiment of this application. As shown, the adjustment structure 35 includes a base plate 350, an adjustment plate 351, a pitch adjustment member (not shown), and a yaw adjustment member (not shown).

[0108] In one embodiment, the adjusting plate 351 includes an outer plate 3510 connected to the main shaft 32 and an inner plate 3511 located inside the outer plate 3510. A first side of the inner plate 3511 is connected to the outer plate 3510, and a gap 3512 is provided between the second side of the inner plate 3511 and the outer plate 3510. The gap 3512 provides deformation space so that the outer plate 3510 can elastically deform relative to the inner plate 3511. The second side is disposed opposite to the first side, and the main shaft 32 is fixedly connected to the outer plate 3510.

[0109] In one embodiment, the base plate 350 is connected to the housing 310 and spaced apart on one side of the adjustment plate 351, the adjustment plate 351 is located between the main shaft 32 and the base plate 350, and the inner plate 3511 is fixedly connected to the base plate 350.

[0110] In one embodiment, the pitch adjustment member is used to provide a resisting force acting on the substrate 350 or the outer plate 3510, pressing the upper portion of the substrate 350 or the outer plate 3510 against the substrate 350, forcing the outer plate 3510 to undergo elastic deformation relative to the inner plate 3511, so that the outer plate 3510 produces a pitch angle change in the front-back direction relative to the vertical; in this embodiment, the pitch adjustment member is inserted inside the outer plate 3510 and can be screwed in the front-back direction, so that the outer plate 3510 can drive the main shaft 32 to pitch relative to the Z-axis in the front-back direction.

[0111] In one embodiment, the yaw adjustment member is used to provide a holding force acting on the inner plate 3511 to keep the inner plate 3511 stationary and to cause the outer plate 3510 to elastically deform relative to the inner plate 3511, so that the outer plate 3510 yaws at a different angle relative to the vertical in the left-right direction. In this embodiment, the yaw adjustment member is threaded through the outer plate 3510 and can press against the inner plate 3511 in the left-right direction, so that the outer plate 3510 can drive the main shaft 32 to yaw relative to the Z-axis in the left-right direction.

[0112] In one embodiment, when it is necessary to adjust the pitch angle of the spindle 32, the pitch adjustment member is turned in the front-back direction so that the pitch adjustment member presses against the base plate 350 or the upper part of the outer plate 3510 presses against the base plate 350. Since the inner plate 3511 and the base plate 350 remain stationary, the inner plate 3511 has a connection restriction function to the outer plate 3510. That is, under the rotational movement of the pitch adjustment member and the connection restriction function of the inner plate 3511, the outer plate 3510 will undergo elastic deformation relative to the inner plate 3511, so that the upper part and the lower part of the outer plate 3510 move in opposite directions in the front-back direction, so that the outer plate 3510 tilts relative to the Z-axis in the front-back direction. This causes the outer plate 3510 to drive the spindle 32 to move to the tilted state, so that the axis of the spindle 32 deflects relative to the Z-axis in the front-back direction, thereby realizing the adjustment of the pitch angle of the spindle 32.

[0113] In one embodiment, when it is necessary to adjust the yaw angle of the spindle 32, the yaw adjustment member is turned in the left-right direction until it presses against the inner plate 3511. Since the inner plate 3511 remains stationary, the outer plate 3510 will undergo elastic deformation relative to the inner plate 3511 under the twisting motion of the yaw adjustment member and the connection restriction of the inner plate 3511. This causes the upper and lower parts of the outer plate 3510 to move in opposite directions in the left-right direction, causing the outer plate 3510 to tilt in the left-right direction relative to the Z-axis. This causes the outer plate 3510 to drive the spindle 32 to move to the tilted state, causing the axis of the spindle 32 to deflect in the left-right direction relative to the Z-axis, thereby achieving the adjustment of the yaw angle of the spindle 32.

[0114] Using the above method, the elastic deformation between the outer plate 3510 and the inner plate 3511 is utilized, so that the outer plate 3510 can drive the spindle 32 to move to an inclined state. The entire adjustment structure only includes the adjustment plate 351, the base plate 350, the pitch adjustment component and the yaw adjustment component located on one side of the spindle 32. It is small in size and light in weight, and the spindle 32 is not prone to deformation during long-term operation, so there will be no problem of wafer breakage, and the grinding effect of the spindle 32 on the wafer can be guaranteed.

[0115] It should be noted that the gap between the adjusting plate 351 and the base plate 350 is small, generally 2mm. Therefore, it will not affect the fixed connection between the inner plate 3511 of the adjusting plate 351 and the base plate 350, while providing space for the movement and elastic deformation of the outer plate 3510 of the adjusting plate 351.

[0116] Furthermore, the adjusting plate 351 is made of metal, which on the one hand allows it to have a certain degree of elasticity and be able to undergo elastic deformation; on the other hand, it ensures high support strength to guarantee the support function for the main shaft 32. Since the adjustment range of the pitch and yaw angles of the main shaft 32 is relatively small, the adjusting plate 351 only needs to be made of metal with a certain degree of elastic deformation; it does not need to undergo large elastic deformation.

[0117] In this embodiment, as Figure 14 As shown, the outer plate 3510 and the inner plate 3511 are integrally formed. A groove is provided around the outer periphery of the inner plate 3511, forming the aforementioned gap 3512. In this embodiment, the formation and size of the gap 3512 are not limited, as long as the outer plate 3510 and the inner plate 3511 maintain a certain gap 3512 while remaining connected, so that the gap 3512 can accommodate the elastic deformation of the outer plate 3510 relative to the inner plate 3511, ensuring that the outer plate 3510 can smoothly undergo elastic deformation.

[0118] like Figure 14As shown, a mounting platform 3513 protrudes from the lower end of the outer plate 3510. The mounting platform 3513 has a U-shaped structure, and both ends of the mounting platform 3513 extend upward along the Z-axis. The spindle 32 is fixedly connected to the mounting platform 3513. The U-shaped mounting platform 3513 ensures the stability and reliability of the connection between the spindle 32 and the outer plate 3510. By setting the mounting platform 3513, on the one hand, it can better adapt to the installation position of the spindle 32, making it easier to install the spindle 32 on the mounting platform 3513; and on the other hand, it allows the spindle 32 to be spaced apart from the outer plate 3510, preventing the spindle 32 from interfering with the elastic deformation of the outer plate 3510. On the other hand, compared to directly installing the spindle 32 on the outer plate 3510, only the mounting platform 3513 needs to be machined on the outer plate 3510, eliminating the need to machine the entire mounting surface of the outer plate 3510, thus reducing the machining difficulty and saving machining costs.

[0119] Specifically, please refer to Figure 13 and combined Figure 14 The pitch adjustment component includes two synchronously adjustable pitch bolts 352, which are spaced apart in the left-right direction at the upper part of the outer plate 3510 and pass through the outer plate 3510; correspondingly, a first threaded hole 3514 for installing the pitch bolts 352 is provided at the upper part of the outer plate 3510.

[0120] When the pitch bolt 352 is screwed along the first screwing direction until it presses against the base plate 350, the upper part of the outer plate 3510 can move away from the base plate 350 on the pitch bolt 352 due to the blocking effect of the base plate 350. At the same time, since the inner plate 3511 has a connecting and restricting effect on the outer plate 3510, the outer plate 3510 will undergo elastic deformation relative to the inner plate 3511, so that the lower part of the outer plate 3510 can move closer to the base plate 350, so that the outer plate 3510 and the spindle 32 tilt forward relative to the inner plate 3511, thereby realizing the adjustment of the tilt angle of the spindle 32.

[0121] When the pitch bolt 352 is turned in a second turning direction opposite to the first turning direction, the upper part of the outer plate 3510 moves on the pitch bolt 352 to press against the base plate 350. Due to the blocking effect of the base plate 350 on the upper part of the outer plate 3510, and the connection and restriction effect of the inner plate 3511 on the outer plate 3510, the outer plate 3510 undergoes elastic deformation relative to the inner plate 3511, allowing the lower part of the outer plate 3510 to move away from the base plate 350, so that the outer plate 3510 and the spindle 32 tilt backward relative to the inner plate 3511, thereby realizing the adjustment of the backward tilt angle of the spindle 32. In this embodiment, the pitch bolt 352 is an adjusting bolt.

[0122] Specifically, as shown in Figure 13, the yaw adjustment component includes a first yaw bolt 353 and a second yaw bolt (not shown). The first yaw bolt 353 and the second yaw bolt are respectively threaded onto two opposite vertical sides of the outer plate 3510. Both the first yaw bolt 353 and the second yaw bolt are located at the lower end of the outer plate 3510; correspondingly, as shown in Figure 13, the yaw adjustment component includes a first yaw bolt 353 and a second yaw bolt (not shown). Figure 14 As shown, a second threaded hole 3515 for mounting a first yaw bolt 353 and a second yaw bolt is provided on the vertical side of the lower end portion of the outer plate 3510. In this embodiment, the first yaw bolt 353 and the second yaw bolt have the same structure and are adjusting bolts.

[0123] Specifically, when the first yaw bolt 353 is screwed to press against the inner plate 3511, the inner plate 3511 blocks the first yaw bolt 353, allowing the lower part of the outer plate 3510 to move to the left on the first yaw bolt 353. At the same time, due to the connection restriction of the inner plate 3511 to the outer plate 3510, the outer plate 3510 undergoes elastic deformation relative to the inner plate 3511, allowing the upper part of the outer plate 3510 to move to the right, so that the outer plate 3510 and the main shaft 32 yaw to the right relative to the inner plate 3511, thereby achieving the adjustment of the rightward yaw angle of the main shaft 32. When the second yaw bolt is screwed on to press against the inner plate 3511, the lower part of the outer plate 3510 can move to the right on the second yaw bolt due to the blocking effect of the inner plate 3511 on the second yaw bolt. At the same time, due to the connection restriction effect of the inner plate 3511 on the outer plate 3510, the outer plate 3510 undergoes elastic deformation relative to the inner plate 3511, thereby allowing the upper part of the outer plate 3510 to move to the left, so that the outer plate 3510 and the main shaft 32 yaw to the left relative to the inner plate 3511, thereby realizing the adjustment of the angle of leftward yaw of the main shaft 32.

[0124] Furthermore, such as Figure 14 As shown, a plurality of mounting holes 3516 are provided on the outer plate 3510. The mounting holes 3516 are used to fix the outer plate 3510 to the base plate 350 after the spindle 32 is pitched or yawed, so as to ensure the stability of the outer plate 3510 and the spindle 32 during operation.

[0125] In summary, the adjustment structure of this application can adjust the pitch and yaw angles of the spindle relative to the Z-axis. Moreover, the entire adjustment structure is small in size and light in weight, making it less likely for the spindle to deform during long-term operation, thereby ensuring the spindle's grinding effect on the wafer.

[0126] To prevent the grinding wheel from easily shaking during the grinding operation and affecting the grinding accuracy of the wafer, in one embodiment, such as Figure 13As shown, the wafer grinding machine also includes an elastic support mechanism 36, which is configured to provide support for the drive module 31 when the grinding wheel 30 rotates. For example, the elastic support mechanism 36 is a nitrogen spring, with its two ends hinged to the housing 310 and the spindle 32, respectively, thereby providing support for the spindle 32 of the grinding wheel 30. Furthermore, the number of elastic support mechanisms 36 is set to two, and the two elastic support mechanisms 36 are symmetrically arranged on both sides of the grinding mechanism to prevent the grinding mechanism from tilting due to uneven force, which would affect the grinding effect.

[0127] In one embodiment, the number of the spindle and the grinding wheel can be set as follows: Figure 1 and Figure 13 The single set shown can also be configured as two or more sets. In one example, the wafer grinding machine includes two spindles and two grinding wheels to enable two-stage grinding of the wafer, with one grinding wheel mounted on each spindle. One set of spindles and grinding wheels is used for the first-stage grinding of the wafer, such as rough grinding, while the other set of spindles and grinding wheels is used for the second-stage grinding of the wafer, such as fine grinding. For example, Figure 1 A set of independently driven grinding mechanisms can also be provided on the rear side of the spindle and grinding wheel, and the plate support can contact the spindle and grinding wheel on the rear side.

[0128] In one embodiment, the control device includes a storage unit and a processing unit. In this embodiment, the control device is, for example, a computer device with memory and a processor, such as an industrial control computer or control board device for a CNC machine tool, used to control the various actuators / components of the grinding machine to perform grinding operations on the wafer on the wafer support table according to the received work instructions.

[0129] In some embodiments, the processing unit includes an integrated circuit chip with signal processing capabilities; or a general-purpose processor, such as a digital signal processor (DSP), application-specific integrated circuit (ASIC), discrete gate or transistor logic device, or discrete hardware component, capable of implementing or executing the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0130] In some embodiments, the storage unit may include random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc. The memory is used to store programs (e.g., programs corresponding to the wafer grinding method), which the processor executes upon receiving execution instructions.

[0131] When the control device receives a grinding start command, it controls the wafer support to move relative to the grinding wheel to a position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, based on the coordinate data of the wafer support and the specifications of the grinding wheel. Then, the grinding wheel contacts the surface of the wafer to be ground, driving the grinding wheel and / or the wafer support to rotate relative to each other to perform grinding operations on the wafer, forming a thicker annular region on the edge of the wafer relative to the surface to be ground. The width of the annular region is the difference between the radius of the wafer and the diameter of the grinding wheel. The grinding start command is generated based on a user trigger. For example, the control device generates the grinding start command based on a user trigger on a touchscreen or a start button. The triggering device is connected to the control device.

[0132] In one embodiment, the control device is further configured to acquire coordinate data of the wafer support stage and specification data of the grinding wheel corresponding to the wafer supported on the wafer support stage.

[0133] The coordinate data of the wafer support stage indicates its position on the grinding machine. Furthermore, given the known position of the grinding wheel on the grinding machine, the relative position between the grinding wheel and the wafer support stage can be determined based on the coordinate data of the wafer support stage. Since the position of the wafer to be processed on the wafer support stage is fixed, the control device can also determine the relative position between the grinding wheel and the center of the wafer based on the relative position between the grinding wheel and the wafer support stage.

[0134] In one embodiment, the wafer grinding machine includes a servo motor for driving the wafer stage and an encoder for the servo motor, wherein the coordinate data of the wafer stage is obtained by reading the angular displacement recorded by the encoder.

[0135] In one embodiment, the control device further acquires the coordinate data of the grinding wheel so that the control device can determine the relative position of the grinding wheel and the bearing platform based on the coordinate data of the grinding wheel. The coordinate data of the grinding wheel indicates the position of the grinding wheel on the grinding machine.

[0136] In one embodiment, the coordinate data of the receiving platform includes either the initial coordinate data of the receiving platform or the current coordinate data of the receiving platform. The initial coordinate data refers to the position of the receiving platform at the loading station, while the current coordinate data refers to the position of the receiving platform at any given moment during its movement from the loading station to the unloading station. That is, the current coordinate data can also be the initial coordinate data.

[0137] The specifications of the grinding wheel indicate its dimensions. For example, the diameter or radius of the grinding wheel can be obtained by knowing its specifications. In one embodiment, the grinding machine includes an input device for providing a human-machine interface for a user to pre-input the specifications of the grinding wheel. An example of the input / output device is a touchscreen connected to the control device.

[0138] In another embodiment, the grinding machine includes a detection device for real-time detection of the grinding wheel's dimensional data. The detection device includes a visual inspection device or a contact measuring device. The visual inspection device determines the grinding wheel's dimensional data in real-time based on the detected image. An example of a contact measuring device is a contact dimensional measuring instrument.

[0139] In one embodiment, the control device also acquires the specification data of the wafer carried on the wafer support stage. The wafer specification data represents the size of the wafer. For example, the wafer size is its diameter or radius. Thus, the control device promptly determines the size of the wafer carried on the wafer support stage to ensure that the size of the wafer on the wafer support stage matches the size of the grinding wheel. The wafer specification data can be pre-input by the user in the input device described above, or it can be obtained by the detection device in real time.

[0140] The projection circle of the grinding wheel is formed by projecting the grinding wheel, mounted on the main shaft, onto a horizontal plane. For example, the horizontal plane is a plane passing through the center point of the wafer. The axis of the wafer is perpendicular to the horizontal plane.

[0141] After determining the coordinate data of the wafer support stage, the control device can determine the relative position of the grinding wheel and the center of the wafer. Then, based on the specifications of the grinding wheel, it controls the wafer support stage to move relative to the grinding wheel until the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel. Here, "tangent to the outer edge of the projection circle" means that the outer edge of the projection circle and the axis have an intersection point. For example, if the projection circle of the grinding wheel is formed by projecting the grinding wheel, mounted on the spindle, onto a horizontal plane passing through the center point of the wafer, then the intersection point is the center point of the wafer. Please refer to [link to relevant documentation]. Figure 15 The diagram shows a schematic representation of an embodiment of this application where the outer edge of the projection circle of the grinding wheel is tangent to the axis of the wafer. Figure 15 As shown, a wafer 4 rests on the wafer support stage 2. The center o of the wafer support stage 2 (i.e., the center of the wafer 4) is located on the outer edge of the projection circle T1 of the grinding wheel. That is, the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, and the edge of the wafer forms a thicker annular region H relative to the surface to be ground. The width of the annular region H is the difference between the radius of the wafer and the diameter of the grinding wheel. For example, the distance between the dashed lines L1 and L2 in the figure is the difference between the radius of the wafer and the diameter of the grinding wheel. Thus, when the grinding wheel and the wafer are in the relative position shown in the figure, the grinding wheel contacts the surface of the wafer to be ground, driving the grinding wheel and / or the wafer support stage to rotate relative to each other to perform a grinding operation on the wafer.

[0142] In one embodiment, the control device further determines the motion path of the wafer stage and / or the grinding wheel, such that the wafer stage moves relative to the grinding wheel to a position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel. The motion path can be a straight path or a curved path. For example, Figure 1 The movement path of the platen of the grinding machine shown is a straight line.

[0143] Furthermore, the grinding machine includes a photoelectric sensor for detecting the movement distance of the wafer support table relative to the grinding wheel. By setting the photoelectric sensor, the position of the wafer support table can be detected in real time, thereby determining whether the wafer support table has moved to a preset position relative to the grinding wheel. The preset position includes the working position, the position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, the loading station, and the unloading station, etc.

[0144] In one embodiment, the storage unit of the control device pre-stores a pre-established correlation between the initial coordinate data of the wafer stage, the specification data of the grinding wheel, and the specification data of the wafer. The user can directly determine the specification data of the grinding wheel corresponding to a specific wafer size based on this correlation, allowing the user to directly replace the grinding wheel according to the correlation. Furthermore, the correlation also includes the correspondence between the above three data points and the motion path. For example, when the horizontal position of the grinding wheel remains constant, the control device determines the corresponding motion path based on the current initial coordinate data of the wafer stage, the specification data of the grinding wheel, and the specification data of the wafer, so that the wafer stage moves to a position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel.

[0145] In one embodiment, the control device is further configured to, upon receiving a detection that the wafer carried on the wafer support stage is different from the wafer from the previous grinding operation, read the specification data of the grinding wheel, and, if it is determined that the specification data of the grinding wheel does not correspond to the specification data of the wafer carried on the wafer support stage, output alarm information or prompt information. The alarm information includes: audible alarms, visual alarms, etc. The prompt information includes, for example, prompt text or images on the user interface.

[0146] With multiple wafers supported on the wafer support platform, the control device controls the wafer support platform to move relative to the grinding wheel until the axis of one of the wafers is tangent to the outer edge of the projection circle of the grinding wheel. Furthermore, when the control device detects that one of the wafers has completed the grinding operation, it controls the wafer support platform to rotate so that the axis of the other un-ground wafer moves to a position tangent to the outer edge of the projection circle of the grinding wheel.

[0147] In one embodiment, please refer to Figure 16 The figure shows a schematic diagram of the structure of a multi-station wafer grinding machine in one embodiment of this application. As shown in the figure, the wafer grinding machine includes: a base 1', a wafer support 2', a grinding mechanism 3', and a control device (not shown).

[0148] The base 1' described above has the same or similar function and structure as the base 1 of the single-station wafer grinding machine described above, and will not be repeated here.

[0149] The wafer support stage 2' is mounted on an indexing stage 5'. The indexing stage 5' rotates to move the wafer support stage 2' relative to the grinding wheel in the grinding mechanism 3' until the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel. In one embodiment, the wafer support stage 2' is provided with a chuck for adsorbing and fixing the wafer. The chuck has the same or similar function and structure as the chuck 20 of the single-station wafer grinding machine described above, and will not be described again here.

[0150] In one embodiment, the wafer is directly attached to a wafer holder on the wafer support stage 2'. This wafer holder has the same or similar function and structure as the wafer holder 23 of the single-station wafer grinding machine described above, and will not be described again here. In another embodiment, the wafer is mounted on the wafer support stage 2' via an adapter plate. This adapter plate has the same or similar function and structure as the adapter plate 21 of the single-station wafer grinding machine described above, and will not be described again here.

[0151] In one embodiment, multiple wafer support stages 2' are provided, evenly arranged on the indexing table 5'. The number of spindles in the grinding mechanism 3' is one less than the number of wafer support stages 2', allowing the wafer support stages 2' and spindles to work together to simultaneously process multiple wafers, thus increasing processing efficiency. In this embodiment, three wafer support stages 2' are provided, and two spindles are provided. One spindle is a rough grinding spindle, and the other is a fine grinding spindle. The rough grinding spindle refers to a spindle with grinding wheels of 200 to 800 mesh, which can quickly remove a large amount of silicon debris from the wafer surface. The fine grinding spindle refers to a spindle with grinding wheels of 1500 to 8000 mesh. The fine grinding spindle can refine the remaining dimensions from the rough grinding to a suitable thickness and repair or reduce the damaged layer generated on the wafer during the rough grinding process.

[0152] In other embodiments, a polishing spindle can be provided, with a higher-purpose grinding wheel mounted on it to refine the surface of the wafer, thereby obtaining a smooth, ultra-thin, thinned wafer. The specific number of spindles and wafer carriers is not limited here and can be determined based on the wafer grinding requirements and specific working conditions. Since the grinding wheels gradually wear down during operation, regular maintenance is necessary.

[0153] In the grinding mechanism 3', each set of spindles and grinding wheels includes a corresponding drive module. The drive module has the same or similar function and structure as the drive module 31 of the single-station wafer grinding machine described earlier, and will not be described again here. In one embodiment, each set of spindles and grinding wheels in the grinding mechanism 3' is provided with a corresponding adapter. The adapter has the same or similar function and structure as the adapter 33 of the single-station wafer grinding machine described earlier, and will not be described again here. In one embodiment, each set of spindles and grinding wheels in the grinding mechanism 3' is provided with a corresponding adjustment structure. The adjustment structure has the same or similar function and structure as the adjustment structure 35 of the single-station wafer grinding machine described earlier, and will not be described again here.

[0154] In one embodiment, the drive module of the grinding mechanism 3' further includes a drive mechanism capable of driving the spindle to move in the horizontal direction. This drive mechanism includes a drive member that drives the spindle to move in the front-to-back direction and / or a drive member that drives the spindle to move in the left-to-right direction. The drive member is, for example, a cylinder. It should be noted that in other embodiments, the drive mechanism can also be of other structures, as long as it can drive the spindle to move in the horizontal direction.

[0155] In one embodiment, the wafer grinding machine includes a centering member 7' on the machine base 1' for centering the placed wafer. Due to the centering effect of the centering member 7' on the wafer center, the center of the wafer can coincide with the center of the wafer support stage 2' when the wafer on the centering member 7' is placed on the support stage 2'. Specifically, after the wafer is centered, the center of the wafer coincides with the center of the centering member 7', and the first robotic arm 8' places the wafer on the support stage 2', with the wafer center coinciding with the center of the support stage 2'. Furthermore, the centering member 7' may also be equipped with a contact measuring device, which can obtain the wafer's specification data through the centering operation.

[0156] In one embodiment, the wafer grinding machine includes a wafer tray 6' disposed on the machine base 1' for placing wafers and a detection device (not shown) disposed on the wafer tray 6' for detecting the size of the wafer tray. The detection device obtains the wafer's specification data by detecting the size of the wafer tray. In one embodiment, two wafer trays 6' may be placed on the machine base 1' to place the wafers after grinding into a new wafer tray 6'. The number of wafer trays 6' on the machine base 1' is not limited and can be determined according to specific working conditions.

[0157] In one embodiment, by selecting one of several sized cassettes 6' to place on the base 1', the first robotic arm 8' moves the wafers from the cassettes 6' to the centering member 7' so that the centering member 7' centers the wafers. This allows the wafers to be placed on the wafer support 2' with their centers coinciding with the center of the support table 2'. Then, the indexing table 5' rotates the support table 2' relative to the indexing table 5', while the grinding mechanism 3' grinds the wafers on the support table 2', thus completing the wafer processing. Taking one support table 2' in the indexing table 5' as an example, after the indexing table 5' rotates the support table 2' 120 degrees from the loading station, the grinding wheel on the coarse grinding spindle of the grinding mechanism 3' performs coarse grinding on the wafer. Then, the indexing table 5' rotates the support table 2' another 120 degrees, and the grinding wheel on the fine grinding spindle of the grinding mechanism 3' performs fine grinding on the wafer. After the wafer processing is completed, the indexing table 5' drives the wafer receiving table 2' to continue rotating 120 degrees to the unloading station, so that the second robot arm 9' transfers the processed wafer to the material box 6' for holding the processed wafer.

[0158] The data acquired and stored by the control device, as well as its structure and function, are the same as or similar to those described above, and will not be repeated here. The multi-station wafer grinding machine also includes an input device, a detection device, a servo motor driving the wafer support stage, and a photoelectric sensor detecting the movement distance of the wafer support stage relative to the grinding wheel. The functions of the input device, detection device, servo motor driving the wafer support stage, and photoelectric sensor detecting the movement distance of the wafer support stage relative to the grinding wheel are the same as or similar to those described above, and will not be repeated here.

[0159] In some embodiments, this application discloses a wafer grinding method. In some examples, the wafer grinding method can be performed by a single-station grinding machine or a multi-station grinding machine as described above, and more specifically, by a control device configured on the single-station grinding machine or multi-station grinding machine. It should be noted that although this application uses a single-station grinding machine or a multi-station grinding machine as an example of performing the wafer grinding method, it is not limited thereto. In other embodiments, the wafer grinding method can also be performed by a grinding machine with other structures, such as a dual-station grinding machine. The grinding machine only needs to include a wafer support stage for holding the wafer to be ground and a grinding wheel for performing the grinding operation on the wafer. In the following embodiments, if the type of grinding machine is not distinguished in the steps, either a single-station grinding machine or a multi-station grinding machine can be used for execution.

[0160] In one embodiment, please refer to Figure 17The figure shows a flowchart of a wafer grinding method of a grinding machine in one embodiment of the present application. As shown, the wafer grinding method includes steps S110 and S120.

[0161] In step S110, the control device of the grinding machine controls the wafer support to move relative to the grinding wheel to a position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, based on the coordinate data of the wafer support and the specification data of the grinding wheel. The diameter of the grinding wheel is smaller than the radius of the wafer.

[0162] The coordinate data of the receiving platform represents its position on the grinding machine. In one embodiment, the coordinate data of the receiving platform includes either its initial coordinate data or its current coordinate data. The initial coordinate data refers to the position of the receiving platform at the loading station, while the current coordinate data refers to the position of the receiving platform at any given moment during its movement from the loading station to the unloading station. That is, the current coordinate data can also be the initial coordinate data.

[0163] Furthermore, since the position of the grinding wheel on the grinding machine is known (e.g., the coordinate data of the grinding wheel is known), the relative position between the grinding wheel and the wafer support can be determined based on the coordinate data of the wafer support. And since the relative position of the wafer to be processed on the wafer support is determined, the control device can also determine the relative position between the grinding wheel and the center of the wafer based on the relative position between the grinding wheel and the wafer support.

[0164] In one embodiment, before executing step S110, the control device further acquires the coordinate data of the grinding wheel so that the control device can determine the relative position of the grinding wheel and the bearing platform based on their coordinate data. The coordinate data of the grinding wheel indicates its position on the grinding machine.

[0165] The specifications of the grinding wheel indicate its dimensions. For example, by obtaining the specifications of the grinding wheel, its diameter or radius can be determined.

[0166] Before executing step S110, the control device also acquires the coordinate data of the wafer support stage and the specification data of the grinding wheel corresponding to the wafer supported on the wafer support stage.

[0167] Furthermore, the control device also acquires the specification data of the wafer carried on the wafer support stage. The wafer specification data refers to the size of the wafer. For example, the size of the wafer is its diameter or radius. In this way, the control device can promptly determine the size of the wafer carried on the wafer support stage to ensure that the size of the wafer carried on the wafer support stage matches the size of the grinding wheel.

[0168] In one embodiment, the specifications of the wafers carried on the wafer support stage and / or the specifications of the grinding wheels are pre-input via a human-machine interface. The human-machine interface may be provided by the input device, such as a touchscreen connected to the control device.

[0169] In another embodiment, the specifications of the wafer carried on the wafer support stage and / or the specifications of the grinding wheel are detected in real time by a detection device. The detection device includes a visual inspection device or a contact measuring device. The visual inspection device can determine the specifications of the grinding wheel in real time based on the detected image. The contact measuring device is, for example, a contact dimension measuring instrument or at least one distance sensor located on the alignment member. After alignment, the distance sensor measures the distance between the edge of the wafer and the center of the alignment member (i.e., the center of the wafer), and uses the measured distance as the specifications of the wafer.

[0170] In one embodiment, the coordinate data of the platen stage is obtained by reading the angular displacement recorded by an encoder. The encoder is an encoder used to drive the servo motor of the platen stage.

[0171] The projection circle of the grinding wheel is formed by projecting the grinding wheel, mounted on the main shaft, onto a horizontal plane. For example, the horizontal plane is a plane passing through the center point of the wafer. The axis of the wafer is perpendicular to the horizontal plane.

[0172] The control device, based on the determined relative position of the grinding wheel and the center of the wafer and the specifications of the grinding wheel, controls the wafer support stage to move relative to the grinding wheel until the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel. Here, "tangent to the outer edge of the projection circle" means that the outer edge of the projection circle and the axis intersect at a point. For example, if the projection circle of the grinding wheel is formed by projecting the grinding wheel, mounted on the spindle, onto a horizontal plane passing through the center point of the wafer, then the intersection point is the center point of the wafer. Figure 15 As shown, a wafer 4 is placed on the wafer support stage 2. The center point o of the wafer support stage 2 (i.e., the center point of the wafer) is located on the outer edge of the projection circle T1 of the grinding wheel. That is, the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, and the edge of the wafer forms an annular region H that is thicker than the surface to be ground. The width of the annular region H is the difference between the radius of the wafer and the diameter of the grinding wheel. For example, the distance between the dashed lines L1 and L2 in the figure is the difference between the radius of the wafer and the diameter of the grinding wheel. In the following embodiment, the intersection point is taken as the center point of the wafer for illustration.

[0173] In one specific embodiment, the control device controls the wafer support stage to move toward the grinding wheel, so that the wafer support stage moves to a position where its axis is tangent to the outer edge of the projection circle of the grinding wheel. In this embodiment, the control device achieves this tangency between the axis of the wafer on the wafer support stage and the outer edge of the projection circle of the grinding wheel simply by controlling the movement of the wafer support stage.

[0174] In one example, assuming the grinding machine is a single-station grinding machine, meaning it has one lathe stage. Please refer to [link / reference]. Figure 18 The figure shows a flowchart of the specific steps of step S110 in one embodiment of this application. As shown in the figure, step S110 includes step S1100, step S1101 and step S1102.

[0175] In step S1100, the control device acquires the coordinate data of the wafer support stage to determine the relative distance between the wafer support stage and the grinding wheel. A wafer is supported on the wafer support stage, and the wafer is coaxial with the wafer support stage. The relative distance is the straight-line distance between the grinding wheel and the wafer support stage. For example, the relative distance is the straight-line distance in the horizontal direction between the center of the grinding wheel and the center of the wafer support stage. (See also...) Figure 19a and Figure 19b The figures show schematic diagrams of the wafer support stage before it moves toward the grinding wheel and when it moves to the point where the wafer axis is tangent to the outer edge of the projection circle of the grinding wheel, respectively, in one embodiment of this application. Figure 19a As shown, the wafer support stage is located at the loading station and carries a wafer 4. The control device determines the horizontal straight-line distance L3 between the center m of the grinding wheel 30 and the center o of the wafer support stage based on the initial coordinate data of the wafer support stage at the loading station. It should be noted that in other embodiments, the control device can also directly determine the relative distance based on the current coordinate data of the wafer support stage at any given time.

[0176] In step S1101, the control device generates the motion path of the bearing platform based on the relative distance and the specifications of the grinding wheel. The straight-line distance of the motion path is the difference between the relative distance between the bearing platform and the grinding wheel and the radius of the grinding wheel.

[0177] In this embodiment, the center of the grinding wheel, the starting point of the motion path, and the ending point of the motion path are collinear. In one example, the motion path is a straight line. Figure 19a and 19bAs shown, the control device determines a motion path I1 based on the difference between the relative distance L3 between the plate support and the grinding wheel 30 and the radius r of the grinding wheel. This motion path I1 is a straight line. It should be noted that in other embodiments, the motion path can also be a curved motion path, where the straight-line distance of the curved motion path is the difference between the relative distance between the plate support and the grinding wheel and the radius of the grinding wheel.

[0178] In step S1102, the control device controls the wafer support stage to move relative to the grinding wheel according to the motion path until the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel. For example... Figure 19b As shown, the wafer support stage moves from the dotted line position to the solid line position along the direction of the motion path I1. At this time, the axis of the wafer 4 on the wafer support stage is tangent to the outer edge of the projection circle of the grinding wheel 30.

[0179] It should be noted that, although this application Figure 19a and Figure 19b The illustrated embodiment uses a single-station grinding machine and a single wafer on the wafer support table as an example. However, in other embodiments, when the grinding machine is a multi-station grinding machine or there are multiple wafers on the wafer support table, the control device can also control the movement of the wafer support table to make the axis of each wafer on the wafer support table sequentially tangent to the outer edge of the projection circle of the grinding wheel.

[0180] In another specific embodiment, the control device controls the plate support to move toward the grinding wheel to the working position, and controls the grinding wheel to move toward the plate support so that the outer edge of the projection circle of the grinding wheel moves to a position tangent to the axial direction of the plate support.

[0181] The working position can be a preset position close to the grinding wheel, or it can be the processing station before the grinding wheel is replaced. It should be noted that the grinding wheel is driven together with its corresponding spindle during movement. In one example, a wafer is carried on the wafer support platform, and the wafer and the wafer support platform are coaxial. Specifically, the control device first controls the wafer support platform to move towards the grinding wheel to the working position, for example, from the loading station towards the grinding wheel. The control device acquires the current coordinate data of the wafer support platform at the working position to determine the relative distance between the wafer support platform and the grinding wheel. Then, based on the relative distance and the specifications of the grinding wheel, a movement path for the grinding wheel is generated. The straight-line distance of the movement path is the difference between the relative distance between the wafer support platform and the grinding wheel and the radius of the grinding wheel, wherein the center of the grinding wheel, the starting point of the movement path, and the ending point of the movement path are on the same straight line. Then, the control device controls the grinding wheel to move relative to the wafer support stage according to the motion path until the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel.

[0182] For example, please see Figure 20a and Figure 20b The figures show schematic diagrams of the states when the wafer support stage moves to the working position and when the grinding wheel moves to the point where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, respectively, in one embodiment of this application. As shown in the figures, the control device first controls the wafer support stage to move along the direction of the motion path I2 to the working position. The control device acquires the current coordinate data of the wafer support stage at the working position to determine the relative distance L4 between the wafer support stage and the grinding wheel 30. Then, based on the relative distance L4 and the radius of the grinding wheel 30, a motion path I3 of the grinding wheel 30 is generated, the straight-line distance of which is the difference between the relative distance L4 and the radius of the grinding wheel 30. Then, the control device controls the grinding wheel to move from the dotted line position to the solid line position according to the motion path I3, so that the axis of the wafer on the wafer support stage is tangent to the outer edge of the projection circle of the grinding wheel. It should be noted that in other embodiments, the motion path can also be a curved motion path.

[0183] For example, please refer to Figures 21a to 21c The diagrams show the states of the bearing platform in one embodiment of this application: when it is in the loading station, during the movement of the bearing platform, and when the grinding wheel moves to the working position. Figure 21a As shown, in one of the wafer-bearing stages of the multi-station grinding machine, a wafer 4 is first placed at the loading station. Figure 21b As shown, the control device controls the indexing table 5' to rotate counterclockwise and move along the direction of the motion path I4 until it reaches the working position, i.e. Figure 21cThe position of the wafer support stage 4 is determined. Then, the control device acquires the current coordinate data of the wafer support stage at the working position to determine the relative distance between the wafer support stage and the grinding wheel. For example... Figure 21c As shown, the control device generates a motion path I5 for the grinding wheel 30' based on the relative distance and the radius of the grinding wheel. The straight-line distance of this motion path I5 is the difference between the relative distance and the radius of the grinding wheel. Then, the control device controls the grinding wheel to move from the dotted line position to the solid line position according to the motion path I5, so that the axis of the wafer on the wafer support platform is tangent to the outer edge of the projection circle of the grinding wheel. It should be noted that in other embodiments, the motion path can also be a curved motion path.

[0184] For further information, please refer to [link / reference]. Figure 22a and Figure 22b The figures show schematic diagrams of the states when the wafer stage moves to the working position and when the grinding wheel moves to the point where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, respectively, in one embodiment of this application. Figure 21c When the wafer-bearing stage moves to the working position corresponding to the next grinding wheel 30' (e.g., a fine grinding wheel), that is, from position 21c to... Figure 22a When the position shown is reached, the control device also needs to control the next grinding wheel 30' to move relative to the wafer support stage to a position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, i.e., the grinding wheel 30' moves from... Figure 22a The position of the middle dashed line is moved to Figure 22b At the position indicated by the solid line, the outer edges of the projection circles of both grinding wheels 30' are tangent to the axis of the corresponding wafer.

[0185] It should be noted that, although this application Figures 20a to 22b The illustrated embodiment is based on the example of having only one wafer on the wafer support platform. However, in other embodiments, when there are multiple wafers on the wafer support platform, the control device can also control the movement of the grinding wheel and the wafer support platform to make the axis of each wafer on the wafer support platform sequentially tangent to the outer edge of the projection circle of the grinding wheel.

[0186] In another specific embodiment, the control device controls the grinding wheel to move toward the wafer support stage, so that the outer edge of the projection circle of the grinding wheel moves to a position tangent to the axial direction of the wafer support stage. In this embodiment, the control device achieves this tangency between the axis of the wafer on the wafer support stage and the outer edge of the projection circle of the grinding wheel simply by controlling the movement of the grinding wheel.

[0187] In one embodiment, the control device can also detect the moving distance of the wafer support platform relative to the grinding wheel using a photoelectric sensor. By setting the photoelectric sensor, the position of the wafer support platform can be detected in real time, thereby determining whether the wafer support platform has moved to a preset position relative to the grinding wheel. The preset position includes the working position, the position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, the loading station, and the unloading station, etc.

[0188] In one embodiment, a pre-established correlation exists between the initial coordinate data of the wafer support stage, the specification data of the grinding wheel, and the specification data of the wafer. This correlation can be stored in the control device, allowing the user to directly determine the specification data of the grinding wheel corresponding to a specific wafer size, enabling the user to directly replace the grinding wheel based on this correlation. Furthermore, the correlation also includes the correspondence between the above three data points and the motion path. For example, when the horizontal position of the grinding wheel remains constant, the control device determines the corresponding motion path based on the current initial coordinate data of the wafer support stage, the specification data of the grinding wheel, and the specification data of the wafer, so that the wafer support stage can move to a position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel.

[0189] In step S120, the control device causes the grinding wheel to contact the surface of the wafer to be ground, and drives the grinding wheel and / or the wafer support to rotate relative to each other to perform a grinding operation on the wafer, thereby forming an annular region on the edge of the wafer that is thicker than the surface to be ground. The width of the annular region is the difference between the radius of the wafer and the diameter of the grinding wheel. The surface to be ground is the area to be ground, and the radius of the surface to be ground is the diameter of the grinding wheel.

[0190] In step S120, since the initial height of the grinding wheel is above the wafer support, the control device instructs the spindle to move downward along the Z-axis to make the grinding wheel contact the surface of the wafer to be ground. This causes the grinding wheel on the spindle to contact the surface of the wafer to be ground downward. The grinding operation is performed on the wafer by rotating the grinding wheel, rotating the wafer support, or rotating the wafer support and the grinding wheel in opposite directions.

[0191] Specifically, when the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, the control device controls the grinding wheel to contact the wafer support, and then controls at least one of the grinding wheel and the wafer support to rotate to perform a grinding operation on the wafer. For example, the grinding wheel is controlled to descend to a position where it contacts the wafer support and then begins to rotate. After the grinding operation is completed on the area corresponding to the surface to be ground, the edge of the wafer forms a relatively thick annular region because it has not been ground. The width of the annular region is predetermined, and the corresponding grinding wheel specifications can be determined based on the width of the annular region and the specifications of the wafer.

[0192] In one embodiment, the grinding wheel performs grinding operations on the wafer at a preset processing angle. Specifically, the control device adjusts the pitch and yaw angles of the spindle relative to the Z-axis (vertical direction), thereby enabling the spindle to perform grinding operations on the wafer at a more suitable processing angle.

[0193] In one embodiment, during the grinding operation on the wafer by driving the grinding wheel and / or the wafer support to rotate relative to each other, the thickness of the wafer is also detected in real time to see if it reaches a target value. For example, the target value is 80 micrometers to 10 micrometers. Specifically, during the grinding process on the surface to be ground, the thickness of the area corresponding to the surface to be ground continuously decreases, and the grinding operation stops when the target value is reached.

[0194] In actual grinding operations, there are situations where some wafers cannot be directly adsorbed by the wafer holder. For example, the adsorption holes on the upper surface of the chuck used for processing 12-inch wafers may be located at the edge of the chuck. However, for 4-8 inch wafers, this type of chuck will not be able to adsorb and fix the wafer, and therefore subsequent processing is impossible.

[0195] In one embodiment, to solve the above-mentioned technical problems, the wafer is attached to an adapter plate, the size of which allows it to be held by the wafer stage. Thus, when determining whether the thickness of the wafer in the grinding operation reaches the target value, it is determined based on the measured top surface height of the wafer and the determined reference height of the top surface of the adapter plate.

[0196] Furthermore, after determining that the wafer thickness has reached the target value, the wear amount of the grinding wheel is also determined. In one example, the wear amount can be determined based on the total thickness removed from the wafer by the grinding wheel. In another example, the wear amount can also be determined based on the total usage time of the grinding wheel. When the wear amount is determined to reach the wheel replacement threshold, a signal to replace the grinding wheel is issued to prompt the user to replace the grinding wheel.

[0197] Although this application describes an example of a wafer being held on a wafer support stage and the wafer being coaxial with the wafer support stage, in other embodiments, the wafer support stage may also hold multiple wafers, the multiple wafers being distributed around the center of the wafer support stage and the centers of the multiple wafers being equidistant from the center of the stage.

[0198] With multiple wafers supported on the wafer support platform, the control device controls the platform to move relative to the grinding wheel until the axis of one of the wafers is tangent to the outer edge of the projection circle of the grinding wheel. Specifically, this can be achieved by controlling the movement of the wafer support platform and / or the grinding wheel to make the axis of one of the wafers on the platform tangent to the outer edge of the projection circle of the grinding wheel. The specific control method is the same as or similar to the case where a single wafer is supported on the platform, as described above. The only difference is that the relative position between the grinding wheel and the wafer is determined before determining the movement path, based on the relative position of one wafer on the platform, the coordinate data of the platform, and the coordinate data of the grinding wheel.

[0199] Furthermore, when the control device detects that one of the plurality of wafers has completed the grinding operation, it rotates the wafer support stage so that the axis of the other wafer among the plurality of wafers that has not been ground moves to a position where it is tangent to the outer edge of the projection circle of the grinding wheel.

[0200] In one embodiment, when the control device detects that the wafer on the wafer support stage is different from the wafer from the previous grinding operation, it reads the specification data of the grinding wheel. If it determines that the specification data of the grinding wheel does not correspond to the specification data of the wafer on the wafer support stage, it outputs an alarm message or a prompt message. The alarm message includes: audible alarm, light alarm, etc. The prompt message includes, for example, prompt text or images on the user interface.

[0201] In summary, the wafer grinding method and wafer grinding machine of this application control the movement of the wafer support stage relative to the grinding wheel to a position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, and cause the grinding wheel to contact the surface of the wafer to be ground. This drives the grinding wheel and / or the wafer support stage to rotate relative to each other to perform grinding operations on the wafer, thereby forming a thicker annular region on the edge of the wafer relative to the surface to be ground. Thus, when grinding wafers of different sizes based on the TAIKO grinding process, after changing the grinding wheel on the wafer grinding machine, the operator can avoid repeatedly adjusting the stroke of the wafer support stage, improving production efficiency.

[0202] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. A wafer lapping machine characterized by comprising: include: The machine base is equipped with loading and unloading stations as well as processing stations; A wafer support stage, mounted on the machine base and capable of reciprocating between the loading / unloading station and the processing station, is used to support wafers to be ground. The wafer support stage is equipped with a suction cup for adsorbing the wafers. The suction cup includes a base plate and a top plate adapted to the base plate. The top plate includes top plates of different specifications, and the base plate can be detachably and sealingly connected to any of the different specifications of the top plates. A film holder is mounted on the wafer support stage, and a thin film for bonding the wafers is mounted on the film holder. The wafer support stage includes: a carrier stage for supporting the thin film; a fixing mechanism including a first bracket sleeved around the outer periphery of the carrier stage, a second bracket sleeved around the outer periphery of the first bracket, and a... A locking member is provided for locking the first bracket and the second bracket; wherein, the second bracket is provided with a pressure plate for pressing against the membrane frame, and when the locking member is in a first working position, a clamping force is applied to the corresponding position on the second bracket so that the pressure plate presses against the membrane frame, and when the locking member is in a second working position, the clamping force applied to the second bracket is released; the clamping force applied to the corresponding position on the second bracket when the locking member is in the first working position includes a first clamping force and a second clamping force, the first clamping force is vertically downward so that the pressure plate presses against the membrane frame; the second clamping force is horizontally from the first bracket to the second bracket; A grinding mechanism, mounted on the machine base, includes a spindle, a grinding wheel detachably mounted on the end of the spindle, and a drive module for driving the spindle to move up and down at the processing station. The axis of the grinding wheel coincides with the axis of the spindle. The diameter of the grinding wheel is smaller than the radius of the wafer. The grinding wheel performs grinding operations on the wafer at a preset processing angle. The grinding mechanism also includes an adjustment structure for adjusting the pitch and yaw angles of the spindle relative to the vertical direction. The adjustment structure includes: a base plate mounted on a housing; wherein the housing is mounted on the machine base; and an adjustment plate mounted on the... The base plate is used to connect the main shaft to the main shaft. The adjustment plate changes the pitch angle of the main shaft relative to the vertical by generating partial elastic deformation in a first direction, and changes the yaw angle of the main shaft relative to the vertical by generating partial elastic deformation in a second direction. The adjustment plate includes: an outer plate connected to the main shaft; and an inner plate fixed to the base plate and located inside the outer plate. A first side of the inner plate is connected to the outer plate, and a gap exists between the second side of the inner plate relative to the first side and the outer plate, so that the outer plate can generate elastic deformation relative to the inner plate when subjected to external force. A control device, upon receiving a start grinding command, controls the wafer support to move relative to the grinding wheel to a position where the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel, based on the coordinate data of the wafer support and the specification data of the grinding wheel; and causes the grinding wheel to contact the surface of the wafer to be ground, driving the grinding wheel and / or the wafer support to rotate relative to each other to perform grinding operations on the wafer, so as to form an annular region on the edge of the wafer that is thicker than the surface to be ground, wherein the width of the annular region is the difference between the radius of the wafer and the diameter of the grinding wheel.

2. The wafer lapping machine of claim 1, wherein The control device is also used to acquire the coordinate data of the wafer support stage and the specification data of the grinding wheel corresponding to the wafer supported on the wafer support stage.

3. The wafer grinding machine according to claim 1, characterized in that, The control device is also used to acquire the specification data of the wafer carried on the wafer carrier stage.

4. The wafer grinding machine according to claim 1, characterized in that, It includes an input device for providing a human-machine interface for pre-inputting the specification data of the wafer carried on the wafer carrier and / or the specification data of the grinding wheel.

5. The wafer grinding machine according to claim 1, characterized in that, It includes a detection device for real-time detection of the specification data of the wafers carried on the wafer support stage and / or the specification data of the grinding wheel.

6. The wafer grinding machine according to claim 5, characterized in that, The detection device includes a visual inspection device or a contact measurement device.

7. The wafer grinding machine according to claim 1, characterized in that, The coordinate data of the plate support stage includes: the initial coordinate data of the plate support stage or the current coordinate data of the plate support stage.

8. The wafer grinding machine according to claim 7, characterized in that, It includes a servo motor for driving the plate-bearing stage, an encoder for the servo motor, and the coordinate data of the plate-bearing stage is obtained by reading the angular displacement recorded by the encoder.

9. The wafer grinding machine according to claim 1, characterized in that, It includes a photoelectric sensor for detecting the distance the plate support stage moves relative to the grinding wheel.

10. The wafer grinding machine according to claim 1, characterized in that, The storage unit of the control device pre-stores the initial coordinate data of the wafer stage, the specification data of the grinding wheel, and the pre-established correlation between the specification data of the wafer and the wafer.

11. The wafer grinding machine according to claim 1, characterized in that, The motion path of the plate support stage can be a linear motion path or a curved motion path.

12. The wafer grinding machine according to claim 1, characterized in that, The control device is also used to receive a wafer on the wafer carrier that is different from the wafer in the previous grinding operation, read the specification data of the grinding wheel, and output an alarm message or prompt message when it is determined that the specification data of the grinding wheel does not correspond to the specification data of the wafer on the wafer carrier.

13. The wafer grinding machine according to claim 1, characterized in that, The wafer support stage is equipped with a suction cup for adsorbing wafers, and the axis of the suction cup coincides with the axis of the wafer support stage.

14. The wafer grinding machine according to claim 1, characterized in that, A wafer is supported on the wafer support stage, and the wafer is coaxial with the wafer support stage.

15. The wafer grinding machine according to claim 1, characterized in that, The wafer support stage carries multiple wafers, which are distributed around the center of the wafer support stage and are equidistant from the center of the stage.

16. The wafer grinding machine according to claim 15, characterized in that, With multiple wafers on the wafer support platform, the control device controls the wafer support platform to move relative to the grinding wheel to a position where the axis of one of the wafers is tangent to the outer edge of the projection circle of the grinding wheel.

17. The wafer grinding machine according to claim 16, characterized in that, When the wafer support table is carrying multiple wafers, and the control device learns that one of the wafers has completed the grinding operation, it controls the wafer support table to rotate so that the axis of the other wafer that has not been ground moves to a position tangent to the outer edge of the projection circle of the grinding wheel.

18. The wafer grinding machine according to claim 1, characterized in that, The wafer is attached to an adapter plate whose dimensions allow it to be held in place by the wafer stage.

19. The wafer grinding machine according to claim 18, characterized in that, The adapter board may have one or more chips attached to it.

20. The wafer grinding machine according to claim 18 or 19, characterized in that, It also includes a measuring mechanism for measuring wafer thickness. When the control device determines whether the thickness of the wafer in the grinding operation has reached the target value, it does so based on the top surface height of the wafer measured by the measuring component of the measuring mechanism and the determined reference height of the top surface of the adapter plate.

21. The wafer grinding machine according to claim 20, characterized in that, The measuring mechanism includes a first measuring component and a second measuring component. When the wafer is being ground, the first measuring component measures the top surface height of the wafer in real time, while the second measuring component does not contact the top surface of the adapter plate.

22. The wafer grinding machine according to claim 1, 18, or 19, characterized in that, The control device is also used to determine the wear amount of the grinding wheel after determining that the thickness of the wafer has reached the target value, and to issue a signal to replace the grinding wheel when the wear amount reaches the replacement threshold.

23. The wafer grinding machine according to claim 1, characterized in that, Each of the top plates has at least one through hole, and the shape of the through holes on different top plates is different; when the top plate of any specification is sealed to the bottom plate, each through hole on the top plate and the bottom plate form a workpiece limiting groove. An adsorption hole located in the through hole is formed on the surface of the bottom plate facing the top plate. The adsorption hole communicates with the inner cavity of the bottom plate. An air extraction port communicating with the inner cavity is provided on the side of the bottom plate.

24. The wafer grinding machine according to claim 23, characterized in that, When the through hole is a polygonal hole, a buffer sheet is provided at each apex corner of the hole wall of the polygonal hole.

25. The wafer grinding machine according to claim 23, characterized in that, The through holes are multiple and evenly distributed around the circumference; the inner cavities are multiple and correspond one-to-one with the workpiece limiting grooves, and each inner cavity is connected to an air extraction port; or, the inner cavity is one and is connected to multiple workpiece limiting grooves.

26. The wafer grinding machine according to claim 1, characterized in that, The top plate has a countersunk hole, and the bottom plate has a screw hole corresponding to the countersunk hole. The top plate and the bottom plate are connected by fastening screws located in the countersunk hole.

27. The wafer grinding machine according to claim 23, characterized in that, The base plate includes a first plate and a second plate, which are sealed together. The opposing surfaces of the first plate and the second plate are provided with matching grooves, and the grooves on the first plate and the second plate constitute the inner cavity.

28. The wafer grinding machine according to claim 1, characterized in that, The locking element includes a wedge that can radially pass through the first bracket to extend into the second bracket, and a drive unit that drives the wedge to move radially along the platform.

29. The wafer grinding machine according to claim 1, characterized in that, The second bracket is sleeved on the outer periphery of the first bracket and the membrane frame, and the first bracket is provided with a positioning part for positioning the membrane frame.

30. The wafer grinding machine according to claim 1, characterized in that, The second support is provided with two or more pressure plates, which are evenly arranged around the axis of the platform.

31. The wafer grinding machine according to claim 1, characterized in that, The stage is used to adsorb the film, and the substrate is rotatable about the axis of the stage.

32. The wafer grinding machine according to claim 1, characterized in that, The grinding wheel that can be detachably mounted on the end of the spindle can be a grinding wheel of different specifications.

33. The wafer grinding machine according to claim 32, characterized in that, The spindle is a spindle adapted to the specifications of the grinding wheel.

34. The wafer grinding machine according to claim 1, characterized in that, The grinding mechanism also includes an adapter, which is mounted on the spindle, and grinding wheels of different diameters can be selectively mounted on the adapter.

35. The wafer grinding machine according to claim 34, characterized in that, The adapter includes an adapter plate and an adapter head disposed on the top surface of the adapter plate for connecting the main shaft. The bottom surface of the adapter plate has multiple coaxially arranged limiting ring grooves, and grinding wheels of different diameters can be selectively installed in the corresponding limiting ring grooves.

36. The wafer grinding machine according to claim 35, characterized in that, The adapter plate includes a main plate body and multiple coaxial annular plates of different diameters located on the bottom surface of the main plate body, with the limiting annular groove formed between two adjacent annular plates.

37. The wafer grinding machine according to claim 1, characterized in that, The drive module includes: The housing is mounted on the base; A support member is slidably mounted on the housing to support the main shaft; A lifting drive component is disposed inside the housing and is used to drive the support component to slide in the vertical direction so as to drive the main shaft to perform lifting operations; A rotary drive component, mounted on the housing, is used to drive the spindle to rotate so as to drive the grinding wheel to perform grinding operations.

38. The wafer grinding machine according to claim 37, characterized in that, The support includes a slide plate slidably mounted on the housing and a locking ring fixed on the slide plate, with the main shaft installed in the locking ring.

39. The wafer grinding machine according to claim 37, characterized in that, The grinding mechanism also includes a balancing component disposed on the housing. The output end of the balancing component is connected to the support member and can rise and fall synchronously with the support member to pull the support member.

40. The wafer grinding machine according to claim 1 or 37, characterized in that, It includes a lead screw assembly for driving the plate support table toward the grinding wheel.

41. The wafer grinding machine according to claim 40, characterized in that, It includes a stop assembly disposed on the base to limit the limit displacement of the plate support stage when it moves along its motion path.

42. The wafer grinding machine according to claim 1, characterized in that, The outer plate and the inner plate are integrally formed. The outer periphery of the inner plate is provided with a groove, which forms the gap.

43. The wafer grinding machine according to claim 1, characterized in that, The grinding mechanism includes: A pitch adjustment member is used to provide a pressure force acting on the substrate or the outer plate, pressing the upper part of the substrate or the outer plate against the substrate, forcing the outer plate to undergo elastic deformation relative to the inner plate so that the outer plate produces a pitch angle change in the front-back direction relative to the vertical. A yaw adjustment component is used to provide a holding force acting on the inner plate to keep the inner plate stationary and to cause the outer plate to elastically deform relative to the inner plate, so that the outer plate yaws at a different angle in the left-right direction relative to the vertical.

44. The wafer grinding machine according to claim 1, characterized in that, The outer plate is provided with mounting holes for mounting components, which are used to secure the outer plate to the base plate.

45. The wafer grinding machine according to claim 1, characterized in that, It includes a resilient support mechanism configured to provide support for the drive module as the grinding wheel rotates.

46. ​​The wafer grinding machine according to claim 1, characterized in that, The wafer grinding machine is a single-station grinding machine.

47. The wafer grinding machine according to claim 1, characterized in that, The wafer grinding machine is a multi-station grinding machine.

48. The wafer grinding machine according to claim 1, characterized in that, It includes a wafer tray mounted on the base for placing wafers and a detection device mounted on the wafer tray for detecting the size of the wafer tray. The detection device obtains the specification data of the wafer by detecting the size of the wafer tray.

49. The wafer grinding machine according to claim 1, characterized in that, It includes a centering device mounted on the base for centering the inserted wafer, the centering device obtaining the wafer's specification data through the centering operation.

50. The wafer grinding machine according to claim 1, characterized in that, The wafer support stage is set on an indexing platform. The indexing platform rotates to move the wafer support stage relative to the grinding wheel until the axis of the wafer is tangent to the outer edge of the projection circle of the grinding wheel.

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