Grinding wheel, wafer grinding device and wafer grinding method

Abstract

The invention provides a grinding wheel, a wafer grinding device and a wafer grinding method. The grinding wheel comprises a wheel body, and a first coarse grinding groove, a second coarse grinding groove, a first accurate grinding groove and a second accurate grinding groove are formed in the peripheral side wall of the wheel body; the surface of the first rough grinding groove is provided with rough grinding grains and is used for trimming the circumferential edge shape of the to-be-ground part; the surface of the second coarse grinding groove is provided with coarse grinding grains and is used for finishing the diameter of the to-be-ground part; the surface of the first accurate grinding groove is provided with accurate grinding abrasive particles and is used for trimming the circumferential edge shape of the to-be-ground part; and the surface of the second accurate grinding groove is provided with accurate grinding abrasive particles and is used for finishing the diameter of the to-be-ground part. Through the arrangement, the single grinding wheel integrates two functions of rough grinding and accurate grinding, in the rough grinding process and the accurate grinding process, grinding grooves with the two functions of edge shape finishing and diameter finishing are specifically divided, the four types of grooves are clear in function division and good in finishing effect, so that a wafer to be ground does not need to repeatedly adjust stations between the rough grinding wheel and the accurate grinding wheel, and the grinding efficiency is improved. And the working efficiency of wafer edge trimming is improved.

Description

Technical Field

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

[0002] In the semiconductor manufacturing process, wafer edge trimming is an important process. The edge of the wafer is ground using a grinding wheel to give the wafer a set edge shape and diameter, and to ensure that the edge is smooth and neat.

[0003] In the prior art, the edges of wafers are often trimmed by using a rough grinding wheel and a fine grinding wheel. Generally speaking, the rough grinding wheel is first used to perform preliminary edge shaping and diameter grinding on the wafer, and then the ground morphology is engraved on the fine grinding wheel, and then the fine grinding wheel is used to complete the final wafer edge shape and diameter fine trimming. The applicant believes that there is still room for efficiency improvement in the wafer edge trimming process. Therefore, how to improve the working efficiency of wafer edge trimming has become a technical problem to be solved by those skilled in the art. Summary of the invention

[0004] In view of this, the present application provides a grinding wheel, a wafer grinding device and a wafer grinding method to solve the problem of how to improve the working efficiency of wafer edge trimming in the prior art.

[0005] In order to achieve the above objectives, this application provides the following technical solutions:

[0006] A grinding wheel comprising:

[0007] A wheel body, wherein a peripheral side wall of the wheel body is provided with a first rough grinding groove, a second rough grinding groove, a first fine grinding groove and a second fine grinding groove;

[0008] The surface of the first rough grinding groove has rough grinding grains and is used to trim the peripheral edge shape of the workpiece to be ground;

[0009] The surface of the second rough grinding groove has the rough grinding abrasive grains and is used to adjust the diameter of the workpiece to be ground;

[0010] The surface of the first fine grinding groove has fine grinding abrasive grains and is used to trim the peripheral edge shape of the workpiece to be ground;

[0011] The surface of the second fine grinding groove has the fine grinding abrasive grains and is used to adjust the diameter of the workpiece to be ground.

[0012] Optionally, the first rough grinding groove and the first fine grinding groove both include:

[0013] The first grinding section partially matches the shape of the upper edge of the circumferential edge of the standard part and is used to trim the upper edge of the circumferential edge of the part to be ground;

[0014] The second grinding segment partially matches the shape of the lower edge of the circumferential edge of the standard part and is used to trim the lower edge of the circumferential edge of the part to be ground. The second grinding segment and the first grinding segment are distributed along the axial direction of the wheel body.

[0015] Optionally, the first rough grinding groove and the first fine grinding groove both further include a middle section, and the middle section is transitionally connected between the first grinding section and the second grinding section.

[0016] Optionally, the first rough grinding groove, the second rough grinding groove, the first fine grinding groove and the second fine grinding groove are distributed in sequence along the axial direction of the wheel body.

[0017] Optionally, the particle size of the coarse grinding abrasive particles is between 700 mesh and 900 mesh.

[0018] Optionally, the particle size of the fine grinding abrasive particles is between 3000 mesh and 5000 mesh.

[0019] Optionally, the wheel body includes a first substrate and a second substrate that are integrally formed, the first substrate is formed by bonding the coarse grinding abrasive grains, and the second substrate is formed by bonding the fine grinding abrasive grains.

[0020] Optionally, the first rough grinding groove and the first fine grinding groove have the same shape;

[0021] The second rough grinding grooves and the second fine grinding grooves have the same shape.

[0022] A wafer grinding device comprises a workbench and any one of the grinding wheels described above, wherein the workbench can fix a workpiece to be ground and drive the workpiece to be ground to move in a plane rectangular coordinate system so that the workpiece to be ground can be transferred between the first rough grinding groove, the second rough grinding groove, the first fine grinding groove and the second fine grinding groove.

[0023] A wafer grinding method, applicable to the above-mentioned wafer grinding device, comprises:

[0024] Fix the wafer to be ground on the workbench;

[0025] driving the grinding wheel to rotate around the axis of the grinding wheel;

[0026] Start the workbench and drive the edge of the wafer to be ground to pass through the first grinding section of the first rough grinding groove, the second grinding section of the first rough grinding groove, the second rough grinding groove, the first grinding section of the first fine grinding groove, the second grinding section of the first fine grinding groove and the second fine grinding groove in sequence.

[0027] The grinding wheel provided by the present application comprises a wheel body, wherein the peripheral side wall of the wheel body is provided with a first rough grinding groove, a second rough grinding groove, a first fine grinding groove and a second fine grinding groove; the surface of the first rough grinding groove has rough grinding abrasive grains and is used to trim the peripheral edge shape of the workpiece to be ground; the surface of the second rough grinding groove has rough grinding abrasive grains and is used to trim the diameter of the workpiece to be ground; the surface of the first fine grinding groove has fine grinding abrasive grains and is used to trim the peripheral edge shape of the workpiece to be ground; the surface of the second fine grinding groove has fine grinding abrasive grains and is used to trim the diameter of the workpiece to be ground. With such a configuration, a single grinding wheel integrates the two functions of rough grinding and fine grinding, and in the rough grinding and fine grinding, the grinding grooves are specifically divided into two functions of edge shape trimming and diameter trimming respectively. The four types of grooves have clear functional division of labor, ensuring that the edge trimming operation of the wafer is carried out in an orderly manner and the trimming effect is good. In this way, the edge trimming operation of the wafer to be ground can be completed around a single grinding wheel, and there is no need to repeatedly adjust the workstation between the rough grinding wheel and the fine grinding wheel, thereby improving the working efficiency of wafer edge trimming. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0029] Figure 1 A schematic diagram of the structure of a grinding wheel provided in an embodiment of the present application;

[0030] Figure 2 A schematic diagram of the structure of a wafer grinding device provided in an embodiment of the present application;

[0031] Figure 3 A schematic diagram of the movement trajectory of the wafer in the wafer grinding method provided in an embodiment of the present application.

[0032] exist Figure 1-Figure 3 middle:

[0033] 1. Grinding wheel; 2. Workbench; 3. Wafer;

[0034] 11. a first substrate; 12. a second substrate;

[0035] 101, first rough grinding groove; 102, second rough grinding groove; 103, first fine grinding groove; 104, second fine grinding groove; 1001, first grinding section; 1002, second grinding section; 1003, middle section. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0037] like Figure 1-Figure 3 As shown, an embodiment of the present application provides a grinding wheel 1 for trimming the edge of a wafer, the grinding wheel 1 comprises a wheel body, and the peripheral side wall of the wheel body is provided with a first rough grinding groove 101, a second rough grinding groove 102, a first fine grinding groove 103 and a second fine grinding groove 104; the surface of the first rough grinding groove 101 has rough grinding abrasive grains and is used to trim the circumferential edge shape of the workpiece to be grinded; the surface of the second rough grinding groove 102 has rough grinding abrasive grains and is used to trim the diameter of the workpiece to be grinded; the surface of the first fine grinding groove 103 has fine grinding abrasive grains and is used to trim the circumferential edge shape of the workpiece to be grinded; the surface of the second fine grinding groove 104 has fine grinding abrasive grains and is used to trim the diameter of the workpiece to be grinded.

[0038] With such arrangement, a single grinding wheel 1 integrates the two functions of rough grinding and fine grinding, and in the rough grinding and fine grinding, it is specifically divided into grinding grooves for edge shape trimming and diameter trimming respectively. The four types of grooves have clear functional division of labor, which ensures that the edge trimming operation of the wafer is carried out in an orderly manner with a good trimming effect. In this way, the edge trimming operation of the wafer to be ground can be completed around a single grinding wheel, and there is no need to repeatedly adjust the work station between the rough grinding wheel and the fine grinding wheel, which improves the work efficiency of the wafer edge trimming. Moreover, a single grinding wheel corresponds to a single drive motor, which also saves equipment costs and reduces the complexity of equipment control.

[0039] Moreover, the wafers trimmed by the grinding wheel 1 provided in the present application have a high product yield in the edge trimming process, which is more conducive to the stability of the wafers during transmission and processing, reduces wafer damage and contamination caused by irregular edges, and good wafer edges are easier to accurately position and align, thereby improving the accuracy and consistency of subsequent processes.

[0040] In addition, the applicant also found that the rough grinding wheel in the prior art trims the edge of the wafer. Since the edge shape trimming principle is to construct a shaping groove with a shape corresponding to the edge of the wafer on the rough grinding wheel, and perform overall grinding and trimming of the edge shape of the wafer in the shaping groove, since the initial shape of the wafer to be ground and the shape of the shaping groove are very different, the shaping groove has more contact with the wafer in some parts and less contact with the wafer in some parts, which easily causes uneven wear of the grinding wheel 1 in the groove, causing the working surface to lose the correct geometric shape and reduce the processing accuracy. In this case, in order to ensure that the specifications of the wafer meet the requirements, the grinding wheel 1 needs to be shaped frequently, resulting in a waste of man-hours and a loss of production capacity.

[0041] In order to solve the above problems, the present application also provides some preferred embodiments, the first rough grinding groove 101 and the first fine grinding groove 103 both include a first grinding segment 1001 and a second grinding segment 1002; a part of the first grinding segment 1001 is adapted to the shape of the upper edge of the circumferential edge of the standard part, and the first grinding segment 1001 is used to trim the upper edge of the circumferential edge of the workpiece to be ground; a part of the second grinding segment 1002 is adapted to the shape of the lower edge of the circumferential edge of the standard part, and the second grinding segment 1002 is used to trim the lower edge of the circumferential edge of the workpiece to be ground, and the second grinding segment 1002 and the first grinding segment 1001 are distributed along the axial direction of the wheel body.

[0042] With such arrangement, on the one hand, the first coarse grinding groove 101 and the first fine grinding groove 103 are not designed to be completely consistent with the edge of the standard wafer, but utilize the local area to grind the upper edge and the lower edge of the circumferential edge of the wafer to be ground respectively. This method always relies on the local area in the groove to grind the wafer, which can avoid the problem of uneven wear of the grinding wheel 1 caused by the direct wafer input and the edge extending into the shaping groove in the prior art, greatly reduce the frequency of the shaping of the grinding wheel 1, and avoid frequent shaping of the grinding wheel 1 can also avoid the risks brought by the shaping of the grinding wheel 1 to a certain extent, such as edge defects, abnormal edge roughness, unstable product process parameters, etc., thereby ensuring the stability of product yield. On the other hand, for example, when the upper edge and the lower edge of the circumferential edge of the required standard part are both arc-shaped, then the first grinding segment 1001 and the second grinding segment 1002 are also designed to be arc-shaped, and different parts of the first grinding segment 1001 and the second grinding segment 1002 have different curvatures, so that it can be suitable for wafers with different edge specifications, avoiding the problem of higher costs due to different types of grinding wheels 1 required due to different wafer edge morphologies and specifications.

[0043] Further, in some preferred embodiments, the first rough grinding groove 101 and the first fine grinding groove 103 both further include an intermediate section 1003, and the intermediate section 1003 is transitionally connected between the first grinding section 1001 and the second grinding section 1002. For example, in the cross section where the axis of the wheel body is located, the first grinding section 1001, the intermediate section 1003 and the second grinding section 1002 are all arc-shaped, so that the first rough grinding groove 101 and the first fine grinding groove 103 present a continuous arc shape. In this way, the groove width of the first rough grinding groove 101 and the first fine grinding groove 103 in the axial direction is widened, and the first rough grinding groove 101 and the first fine grinding groove 103 are designed as a groove width widening design, which provides more grinding areas for the wafer to be ground in the groove. It can also be said that the wide groove design is conducive to improving the compatibility of the grinding wheel 1 with the wafer specifications, and is further applicable to the edge trimming operations of more types of wafers, and further reduces the equipment cost.

[0044] In some optional embodiments, the first rough grinding groove 101, the second rough grinding groove 102, the first fine grinding groove 103 and the second fine grinding groove 104 are sequentially distributed along the axial direction of the wheel body. Such a layout is conducive to adapting to conventional operation logic and simplifying the writing of wafer movement logic program.

[0045] Of course, in order to adapt to unconventional processing methods, the axial position relationship between the first rough grinding groove 101, the second rough grinding groove 102, the first fine grinding groove 103 and the second fine grinding groove 104 can be arranged arbitrarily.

[0046] In some optional embodiments, the first rough grinding groove 101 and the first fine grinding groove 103 have the same shape. For example, the first rough grinding groove 101 and the first fine grinding groove 103 can be arc-shaped; the second rough grinding groove 102 and the second fine grinding groove 104 have the same shape, and the shapes of the second rough grinding groove 102 and the second fine grinding groove 104 can be the same as the circumferential edge of the wafer, or they can be different. In this way, the movement trajectory of the wafer in the rough grinding stage and the fine grinding stage is basically similar. Under different wafer specifications, the rough grinding movement trajectory and its own fine grinding movement trajectory are still unified, which is conducive to the writing of the wafer movement logic program.

[0047] In some specific embodiments, the particle size of the coarse grinding abrasive particles of the wheel body is between 700 mesh and 900 mesh, which can effectively meet the process standard of coarse grinding. For example, the coarse grinding abrasive particles can be set to a particle size of 800 mesh.

[0048] In some specific embodiments, the particle size of the fine grinding abrasive grains of the wheel body is between 3000 mesh and 5000 mesh, which can effectively meet the process standard of fine grinding. For example, the fine grinding abrasive grains can be set to a particle size of 3000 mesh.

[0049] In some optional embodiments, the wheel body includes an integrally formed first matrix 11 and a second matrix 12, the first matrix 11 is formed by bonding coarse grinding abrasive grains, and the second matrix 12 is formed by bonding fine grinding abrasive grains. In this configuration, the coarse grinding abrasive grains are mixed with the required molding materials such as adhesives and filled into a mold, and the fine grinding abrasive grains are mixed with the required molding materials such as adhesives and filled into a mold, and the first matrix 11 and the second matrix 12 are fixed as a whole while being formed, and the grinding wheel 1 integrates the dual functions of coarse grinding and fine grinding, while ensuring the stability of the abrasive grains on the grinding wheel 1.

[0050] Of course, in addition to the above method, it is also feasible to provide a substrate with the same material throughout, and shape the coarse grinding abrasive grains to the corresponding parts of the substrate, and shape the fine grinding abrasive grains to the corresponding parts of the substrate.

[0051] Based on the above-mentioned grinding wheel 1, the embodiment of the present application further provides a wafer grinding device, which includes a workbench 2 and the above-mentioned grinding wheel 1, please refer to Figure 2, the grinding wheel 1 does not need to have a position movement track, and can rotate around the axis under the drive of the motor. The workbench 2 can fix the workpiece to be ground and drive the workpiece to be ground to move in the plane rectangular coordinate system, so that the workpiece to be ground is transferred between the first rough grinding groove 101, the second rough grinding groove 102, the first fine grinding groove 103 and the second fine grinding groove 104. The plane rectangular coordinate system refers to the X-axis represented by the horizontal direction and the Z-axis represented by the vertical direction in the figure. The workpiece to be ground is also the wafer 3 in the figure. Exemplarily, it can be set that the workbench 2 can fix and release the wafer 3 through negative pressure adsorption; the movement of the workbench 2 in the X-axis direction and the movement in the Z-axis direction can be achieved by the mechanism of the motor and the ball screw. Since the wafer grinding device has the above-mentioned grinding wheel 1, the beneficial effects of the wafer grinding device brought by the grinding wheel 1 can be found in the above content, which will not be repeated here.

[0052] Based on the above-mentioned wafer grinding device, the embodiment of the present application further provides a wafer grinding method, which comprises the following steps:

[0053] Fixing the wafer to be ground to the workbench 2;

[0054] driving the grinding wheel 1 to rotate around the axis of the grinding wheel 1;

[0055] Start the workbench 2 and move it along the X-axis and the Z-axis to drive the edge of the wafer to be ground to pass through the first grinding segment 1001 of the first rough grinding groove 101, the second grinding segment 1002 of the first rough grinding groove 101, the second rough grinding groove 102, the first grinding segment 1001 of the first fine grinding groove 103, the second grinding segment 1002 of the first fine grinding groove 103 and the second fine grinding groove 104 in sequence.

[0056] According to the different specifications of the wafers to be ground, the execution program of the workbench 2 is correspondingly replaced to make the workbench 2 move along the corresponding motion trajectory.

[0057] With such an arrangement, relying on the grinding wheel 1 provided in the present application, the edge trimming and forming of the wafer can be achieved in one step. It is only necessary to set a reasonable motion trajectory of the workbench 2. The set motion trajectory is executed differently according to different needs. There is no need to frequently switch between the coarse grinding wheel and the fine grinding wheel, which greatly improves the equipment utilization rate and saves time cost.

[0058] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0059] The block diagrams of the devices, apparatuses, equipment, and systems involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

[0060] It should also be noted that in the apparatus, device and method of the present application, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present application.

[0061] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0062] It should be understood that the qualifiers "first", "second", "third", "fourth", "fifth" and "sixth" used in the description of the embodiments of the present application are only used to more clearly explain the technical solutions and cannot be used to limit the scope of protection of the present application.

[0063] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A grinding wheel, characterized in that: It comprises a wheel body, wherein the peripheral side wall of the wheel body is provided with a first rough grinding groove (101), a second rough grinding groove (102), a first fine grinding groove (103) and a second fine grinding groove (104); The surface of the first rough grinding groove (101) has rough grinding grains and is used to trim the peripheral edge shape of the workpiece to be ground; The surface of the second rough grinding groove (102) has the rough grinding abrasive grains and is used to adjust the diameter of the workpiece to be ground; The surface of the first fine grinding groove (103) has fine grinding abrasive grains and is used to trim the circumferential edge shape of the workpiece to be ground; The surface of the second fine grinding groove (104) has the fine grinding abrasive grains and is used to adjust the diameter of the workpiece to be ground.

2. The grinding wheel according to claim 1, characterized in that The first rough grinding groove (101) and the first fine grinding groove (103) both include: The first grinding section (1001) is partially adapted to the shape of the upper edge of the circumferential edge of the standard part and is used to trim the upper edge of the circumferential edge of the part to be ground; The second grinding section (1002) is partially adapted to the shape of the lower edge of the circumferential edge of the standard part and is used to trim the lower edge of the circumferential edge of the part to be ground. The second grinding section (1002) and the first grinding section (1001) are distributed along the axial direction of the wheel body.

3. The grinding wheel according to claim 2, characterized in that The first rough grinding groove (101) and the first fine grinding groove (103) both further include an intermediate section (1003), and the intermediate section (1003) is transitionally connected between the first grinding section (1001) and the second grinding section (1002).

4. The grinding wheel according to claim 1, characterized in that The first rough grinding groove (101), the second rough grinding groove (102), the first fine grinding groove (103) and the second fine grinding groove (104) are distributed in sequence along the axial direction of the wheel body.

5. The grinding wheel according to claim 1, characterized in that The particle size of the coarse grinding abrasive particles is between 700 meshes and 900 meshes.

6. The grinding wheel according to claim 1, characterized in that The particle size of the fine grinding abrasive particles is between 3000 mesh and 5000 mesh.

7. The grinding wheel according to claim 1, characterized in that The wheel body comprises a first matrix (11) and a second matrix (12) which are integrally formed; the first matrix (11) is formed by bonding the coarse grinding abrasive grains, and the second matrix (12) is formed by bonding the fine grinding abrasive grains.

8. The grinding wheel according to claim 1, characterized in that The first rough grinding groove (101) and the first fine grinding groove (103) have the same shape; The second rough grinding groove (102) and the second fine grinding groove (104) have the same shape.

9. A wafer grinding device, characterized in that: The invention comprises a workbench (2) and a grinding wheel as claimed in any one of claims 1 to 8, wherein the workbench (2) is capable of fixing a workpiece to be ground and driving the workpiece to be ground to move in a plane rectangular coordinate system, so that the workpiece to be ground is transferred between the first rough grinding groove (101), the second rough grinding groove (102), the first fine grinding groove (103) and the second fine grinding groove (104).

10. A wafer grinding method, characterized in that: Applicable to the wafer grinding apparatus as claimed in claim 9, the method comprising: Fixing the wafer to be ground onto the workbench (2); driving the grinding wheel (1) to rotate around the axis of the grinding wheel (1); The workbench (2) is started, and the workbench (2) drives the edge of the wafer to be ground to sequentially pass through the first grinding section (1001) of the first rough grinding groove (101), the second grinding section (1002) of the first rough grinding groove (101), the second rough grinding groove (102), the first grinding section (1001) of the first fine grinding groove (103), the second grinding section (1002) of the first fine grinding groove (103), and the second fine grinding groove (104).

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