Wafer thinning apparatus

Abstract

This application discloses a wafer thinning apparatus, including a first spindle, a second spindle, a first grinding wheel, and a second grinding wheel. The first grinding wheel is configured to be mounted on the first spindle when the wafer thinning apparatus is in a first state, and is configured to perform a first rough grinding thinning process on the entire first initial surface of a first wafer to form a first processed surface. The second grinding wheel is configured to be mounted on the second spindle in the first state, and is configured to perform a first fine grinding thinning process on the central region of the first processed surface to form a first target thinned wafer. The first target thinned wafer has a first recess and includes a first edge reinforcement portion. The first recess is obtained through the first fine grinding thinning process, and the first edge reinforcement portion is located at the edge of the first target thinned wafer and surrounds the first recess. This reduces the number of thinning machines required to thin the first wafer, thereby reducing thinning costs, while simultaneously improving the processing efficiency for thinning the first wafer.

Description

Technical Field

[0001] This application relates to the field of semiconductor processing technology, and more particularly to a wafer thinning device. Background Technology

[0002] In semiconductor manufacturing, wafer thinning is a crucial step aimed at reducing the wafer's thickness to meet the requirements of subsequent processes. Currently, among wafer thinning methods, Taiko thinning presents challenges in controlling the thinning process, while conventional full-surface thinning is prone to wafer breakage. Therefore, finding a solution that simultaneously addresses both the difficulty of the thinning process and the susceptibility to wafer breakage is a key issue that needs to be addressed. Utility Model Content

[0003] This application provides a wafer thinning device that reduces the difficulty of thinning a first wafer and reduces the risk of breakage after thinning, thereby at least partially solving the above-mentioned technical problems.

[0004] To achieve the above objectives, according to a first aspect of this application, a wafer thinning apparatus is provided, comprising a first spindle, a second spindle, a first grinding wheel, and a second grinding wheel. The first grinding wheel is configured to be mounted on the first spindle when the wafer thinning apparatus is in a first state, and is configured to perform a first rough grinding thinning process on the entire first initial surface of a first wafer to form a first processed surface. The second grinding wheel is configured to be mounted on the second spindle in the first state, and is configured to perform a first fine grinding thinning process on the central region of the first processed surface to form a first target thinned wafer. The first target thinned wafer has a first recess and includes a first edge reinforcement portion, the first recess being obtained through the first fine grinding thinning process, and the first edge reinforcement portion being located at the edge of the first target thinned wafer and surrounding the first recess.

[0005] Optionally, the first grinding wheel is further configured to be mounted on the first spindle when the wafer thinning device is in the second state, and configured to perform a second rough grinding thinning process on the entire second initial surface of the second wafer to form a second processed surface; wherein the diameter of the second wafer is smaller than the diameter of the first wafer.

[0006] Optionally, the first grinding wheel includes a first mounting part, a first grinding wheel tooth ring, and a first annular part. The first grinding wheel is mounted on the first spindle through the first mounting part, the first annular part is located on the first mounting part, the first grinding wheel tooth ring is located on the first annular part, and the first grinding wheel performs the first coarse grinding thinning process or the second coarse grinding thinning process through the first grinding wheel tooth ring. The first mounting part is provided with a first flow channel, and a through hole is provided at the center of the first annular part. The through hole is connected to the outlet of the first flow channel. The outlet of the first flow channel is configured to supply rinsing liquid, which flows out through the through hole to clean the grinding particles generated during the first coarse grinding and thinning process or the second coarse grinding and thinning process.

[0007] Optionally, the wafer thinning apparatus further includes a first mounting base, which is mounted on the first spindle, and the first mounting portion of the first grinding wheel is mounted on the first mounting base; the first mounting base is provided with a second flow channel, and the inlet of the second flow channel is configured to connect to the inlet of the first flow channel; the first spindle is provided with a third flow channel, and the outlet of the third flow channel is configured to connect to the inlet of the second flow channel.

[0008] Optionally, the wafer thinning apparatus further includes: The third grinding wheel is configured to be mounted on the second spindle in the second state and is configured to perform a second fine grinding and thinning process on the central region of the second processing surface to form a second target thinned wafer; The second target thinned wafer is provided with a second recess and includes a second edge reinforcement portion. The second recess is obtained by the second fine grinding thinning process. The second edge reinforcement portion is located at the edge of the second target thinned wafer and surrounds the second recess.

[0009] Optionally, the thickness of the first edge reinforcement portion along the radial direction of the first target thinned wafer is greater than the thickness of the second edge reinforcement portion along the radial direction of the second target thinned wafer.

[0010] Optionally, the second grinding wheel includes a second mounting portion, a second annular portion, and a second grinding wheel toothed ring. The second annular portion is located on the second mounting portion, the second grinding wheel toothed ring is located on the second annular portion, and the second grinding wheel is mounted on the second spindle via the second mounting portion. The third grinding wheel includes a third mounting part, a third annular part, and a third grinding wheel toothed ring. The third annular part is located on the third mounting part, and the third grinding wheel toothed ring is located on the third annular part. The outer diameter of the third grinding wheel toothed ring is smaller than the outer diameter of the second grinding wheel toothed ring. The third mounting part is the same as the second mounting part. The third grinding wheel is mounted on the second main shaft through the third mounting part.

[0011] Optionally, the axial dimension of the second mounting portion is equal to the axial dimension of the second annular portion, and the axial dimension of the third mounting portion is equal to the axial dimension of the third annular portion.

[0012] Optionally, the first wafer has a diameter of 8 inches and the second wafer has a diameter of 6 inches.

[0013] Optionally, the first wafer has a diameter of 12 inches and the second wafer has a diameter of 8 inches.

[0014] In the wafer thinning apparatus of this application embodiment, the first rough grinding thinning process processes the entire first initial surface of the first wafer to form a first processed surface, also known as conventional full-surface thinning. After the first rough grinding thinning process, the first fine grinding thinning process thins the central region of the first processed surface of the first wafer, also known as Taiko thinning. Thus, the first spindle of the first fine grinding thinning process does not need to be coaxial with the second spindle in the first rough grinding thinning process, reducing the process difficulty of the first fine grinding thinning process and overcoming the problem of high process difficulty caused by requiring the spindles of the two consecutive Taiko thinning processes to remain concentric. Furthermore, the first target thinned wafer is provided with a first recess and includes a first edge reinforcement portion. The first edge reinforcement portion surrounds the first recess and locally thickens the first target thinned wafer, facilitating subsequent processing by picking up the first edge reinforcement portion, overcoming the problem of easy breakage of the thinned wafer caused by two consecutive conventional full-surface thinning processes. Therefore, the first rough grinding and thinning process combined with the first fine grinding and thinning process reduces the difficulty of thinning the first wafer and also reduces the risk of breakage after the first wafer is thinned.

[0015] Furthermore, if a conventional wafer thinning machine is used for the first rough grinding and thinning process, and then a Taiko wafer thinning machine is used for the first fine grinding and thinning process, at least two wafer thinning machines are required in total. In the embodiments of this application, the first spindle and the second spindle belong to the same wafer thinning machine, which can reduce the number of wafer thinning machines required for continuous conventional thinning and Taiko thinning of the first wafer, and reduce the cost of purchasing and maintaining wafer thinning machines. Moreover, it also eliminates the time required for handling the first wafer when it is subjected to conventional full-surface rough grinding and thinning and Taiko fine grinding and thinning on different wafer thinning machines, shortening the overall thinning time of the first wafer and improving the production efficiency of thinning the first wafer. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the wafer thinning apparatus provided in an exemplary embodiment of this application for thinning a first wafer; Figure 2 This is a schematic diagram of the wafer thinning apparatus provided in an exemplary embodiment of this application for thinning a second wafer; Figure 3 This is a three-dimensional structural schematic diagram of the first grinding wheel provided in an exemplary embodiment of this application; Figure 4 This is a schematic cross-sectional view of the first grinding wheel provided in an exemplary embodiment of this application; Figure 5 This is a three-dimensional structural schematic diagram of the second grinding wheel provided in an exemplary embodiment of this application; Figure 6 This is a cross-sectional structural diagram of the second grinding wheel provided in an exemplary embodiment of this application.

[0017] Explanation of reference numerals in the attached figures: 100. Wafer thinning equipment; 11. First spindle; 12. Second spindle; 21. First mounting base; 22. Second mounting base; 3. First grinding wheel; 31. First mounting part; 32. First annular part; 321. Through hole; 33. First grinding wheel tooth ring; 4. Second grinding wheel; 41. Second mounting part; 42. Second annular part; 43. Second grinding wheel toothed ring; 5. Third grinding wheel; 51. Third mounting part; 52. Third annular part; 53. Third grinding wheel toothed ring; S1, first flow channel; S2, second flow channel; S3, third flow channel; 61. The first wafer; 62. First target thinned wafer; 621. First recess; 622. First edge reinforcement; 63. Second wafer; 64. Second target thinned wafer; 641. Second recess; 642. Second edge reinforcement; 7. Nozzle. Detailed Implementation

[0018] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the protection scope of this application.

[0019] Please see Figure 1 and Figure 2 This application provides a wafer thinning apparatus 100, which can perform taiko thinning processing on wafers of different sizes.

[0020] The wafer thinning apparatus 100 includes a first spindle 11 and a second spindle 12. Both the first spindle 11 and the second spindle 12 are fixed on the base (not shown in the figure) of the wafer thinning apparatus 100, and the first spindle 11 and the second spindle 12 are parallel.

[0021] Along the axial direction of the first spindle 11, one end of the first spindle 11 is connected to a first rotary drive source (not shown in the figure) to drive the first spindle 11 to rotate, and the other end of the first spindle 11 is equipped with a first mounting base 21.

[0022] Along the axial direction of the second spindle 12, one end of the second spindle 12 is connected to a second rotary drive source (not shown in the figure) to drive the second spindle 12 to rotate, and the other end of the second spindle 12 is equipped with a second mounting base 22.

[0023] Please see Figure 1 The wafer thinning equipment 100 includes a first grinding wheel 3 and a second grinding wheel 4. The first grinding wheel 3 is a conventional grinding wheel for whole-surface thinning, and the second grinding wheel 4 is a Taiko grinding wheel for central local area thinning.

[0024] The first grinding wheel 3 is configured to be mounted on the first spindle 11 when the wafer thinning equipment 100 is in the first state, and is configured to perform a first rough grinding thinning process on the entire first initial surface of the first wafer 61 to form a first processed surface.

[0025] The second grinding wheel 4 is configured to be mounted on the second spindle 12 in the first state and is configured to perform a first fine grinding thinning process on the central region of the first processing surface to form a first target thinned wafer 62. The first target thinned wafer 62 is provided with a first recess 621 and includes a first edge reinforcement 622. The first recess 621 is obtained through the first fine grinding thinning process, and the first edge reinforcement 622 is located at the edge of the first target thinned wafer 62 and surrounds the first recess 621.

[0026] In the wafer thinning apparatus 100 of this application embodiment, the first rough grinding thinning process processes the entire first initial surface of the first wafer 61 to form a first processed surface, also known as conventional full-surface thinning. After the first rough grinding thinning process, the first fine grinding thinning process thins the central region of the first processed surface of the first wafer 61, also known as Taiko thinning. In this way, the first spindle 11 of the first fine grinding thinning process and the second spindle 12 of the first rough grinding thinning process do not need to be coaxial, reducing the process difficulty of the first fine grinding thinning process and overcoming the problem that the process difficulty is high due to the requirement that the spindles of the two consecutive Taiko thinning processes must be kept concentric. Furthermore, the first target thinned wafer 62 is provided with a first recess 621 and includes a first edge reinforcement 622. The first edge reinforcement 622 surrounds the first recess 621 and locally thickens the first target thinned wafer 62, facilitating subsequent processing by picking up the first edge reinforcement 622. This overcomes the problem of easy breakage of the thinned wafer caused by two consecutive conventional full-surface thinning processes. Therefore, the first rough grinding thinning process combined with the first fine grinding thinning process reduces the process difficulty of thinning the first wafer 61 and reduces the risk of breakage after thinning.

[0027] Furthermore, if a conventional wafer thinning machine is used for the first rough grinding and thinning process, and then a Taiko wafer thinning machine is used for the first fine grinding and thinning process, at least two wafer thinning machines are required in total. In the embodiments of this application, the first spindle 11 and the second spindle 12 belong to the same wafer thinning machine 100, which can reduce the number of wafer thinning machines 100 required for continuous conventional thinning and Taiko thinning of the first wafer 61, and reduce the cost of purchasing and maintaining the wafer thinning machines 100. Moreover, it also eliminates the time required for handling the first wafer 61 when it is subjected to conventional full-surface rough grinding and thinning and Taiko fine grinding and thinning on different wafer thinning machines, shortens the overall thinning time of the first wafer 61, and improves the production efficiency of thinning the first wafer 61.

[0028] In some embodiments, please refer to Figure 2 The first grinding wheel 3 is also configured to be mounted on the first spindle 11 when the wafer thinning equipment 100 is in the second state, and is configured to perform a second rough grinding thinning process on the entire second initial surface of the second wafer 63 to form a second processed surface. The diameter of the second wafer 63 is smaller than the diameter of the first wafer 61. Therefore, since both the first and second rough grinding thinning processes are performed by the first grinding wheel 3, the same conventional full-surface grinding wheel is used for the conventional thinning of wafers of different sizes, reducing the number of conventional grinding wheels required and eliminating the time spent changing conventional grinding wheels of different sizes, further improving the processing efficiency of the first wafer 61 and the second wafer 63 of different sizes.

[0029] In some embodiments, during the first rough grinding and thinning process, the overlap area between the first wafer 61 and the first grinding wheel 3 is a first area. During the second rough grinding and thinning process, the overlap area between the second wafer 63 and the first grinding wheel 3 is a second area, which is smaller than the first area. Thus, when using the same first grinding wheel 3 for conventional full-surface thinning to thin first wafers 61 and second wafers 63 of different diameters, the overlap area between the first grinding wheel 3 and the first wafer 61 is larger, while the overlap area between the first grinding wheel 3 and the second wafer 63 is smaller. The overlap area between the first grinding wheel 3 and the wafer is adaptively adjusted according to the wafer diameter to ensure the efficiency of rough grinding of the first wafer 61 and the second wafer 63.

[0030] In some embodiments, please refer to Figure 1 and Figure 2 The first grinding wheel 3 includes a first mounting portion 31, a first annular portion 32, and a first grinding wheel toothed ring 33. The first grinding wheel 3 is mounted on the first spindle 11 via the first mounting portion 31. The first annular portion 32 is located on the first mounting portion 31. The first grinding wheel toothed ring 33 is located on the first annular portion 32. The first grinding wheel 3 performs the first coarse grinding thinning process or the second coarse grinding thinning process via the first grinding wheel toothed ring 33.

[0031] In some embodiments, please refer to Figure 1 and Figure 2 The first mounting portion 31 is provided with a first flow channel S1, and a through hole 321 is also provided at the center inside the first annular portion 32, which communicates with the outlet of the first flow channel S1. The outlet of the first flow channel S1 is configured to supply rinsing fluid, which flows out through the through hole 321 to clean the abrasive particles generated during the first rough grinding and thinning process or the second rough grinding and thinning process. In this way, during the conventional full-surface thinning process of the first grinding wheel 3 on the first wafer 61 or the second wafer 63, the rinsing fluid flowing out from the first flow channel S1 can rinse and remove the abrasive particles, thereby improving the thinning efficiency. At the same time, the rinsing fluid also plays a role in absorbing and dissipating the large amount of heat generated by friction during the thinning process, thereby achieving a cooling effect.

[0032] In some embodiments, please continue reading Figure 1 and Figure 2The first mounting portion 31 of the first grinding wheel 3 is mounted on the first mounting base 21. The first mounting base 21 is provided with a second flow channel S2, and the inlet of the second flow channel S2 is configured to connect with the inlet of the first flow channel S1. The first spindle 11 is provided with a third flow channel S3, and the outlet of the third flow channel S3 is configured to connect with the inlet of the second flow channel S2. In this way, the rinsing fluid flowing out from the third flow channel S3 of the first spindle 11 flows out to the first flow channel S1 via the second flow channel S2 of the first mounting base 21.

[0033] In some embodiments, please refer to Figure 2 The wafer thinning apparatus 100 also includes a third grinding wheel 5, which is configured to be mounted on the second spindle 12 in the second state and configured to perform a second fine grinding thinning process on the central region of the second processing surface to form a second target thinned wafer 64. Thus, the second grinding wheel 4 and the third grinding wheel 5 can be detachably connected to the same second spindle 12. By replacing the second grinding wheel 4 and the third grinding wheel 5, the wafer thinning apparatus 100 can switch between the first state and the second state, thereby achieving Taiko thinning of the first wafer 61 and the second wafer 63 of different sizes. In other words, one wafer thinning apparatus 100 can achieve Taiko thinning of two different sizes of wafers, reducing the cost of thinning wafers of different sizes.

[0034] In some embodiments, please continue reading Figure 2 The second target thinned wafer 64 is provided with a second recess 641 and includes a second edge reinforcement 642. The second recess 641 is obtained through the second fine grinding thinning process. The second edge reinforcement 642 is located at the edge of the second target thinned wafer 64 and surrounds the second recess 641. The second fine grinding thinning process can improve the surface finish and thickness uniformity of the second target thinned wafer 64. Furthermore, since the second target thinned wafer 64 includes the second edge reinforcement 642, it plays a role in locally thickening the second target thinned wafer 6474, facilitating subsequent processing by picking up the second edge reinforcement 642.

[0035] In some embodiments, the thickness Th1 of the first edge reinforcement 622 along the radial direction of the first target thinned wafer 62 is greater than the thickness Th2 of the second edge reinforcement 642 along the radial direction of the second target thinned wafer 64. Thus, when the diameter of the first wafer 61 is greater than the diameter of the second wafer 63, the radial thickness of the first edge reinforcement 622 of the first target thinned wafer 62 is greater, reducing the risk of damage to the larger-diameter first target thinned wafer 62 during subsequent processing.

[0036] Please see Figure 3 and Figure 4The second grinding wheel 4 includes a second mounting portion 41, a second annular portion 42, and a second grinding wheel toothed ring 43. The second annular portion 42 is located on the second mounting portion 41, and the second grinding wheel toothed ring 43 is located on the second annular portion 42. The second grinding wheel 4 is mounted on the second spindle 12 via the second mounting portion 41.

[0037] Please see Figure 5 and Figure 6 The third grinding wheel 5 includes a third mounting portion 51, a third annular portion 52, and a third grinding wheel toothed ring 53. The third annular portion 52 is located on the third mounting portion 51, and the third grinding wheel toothed ring 53 is located on the third annular portion 52. The third grinding wheel 5 is mounted on the second main shaft 12 via the third mounting portion 51.

[0038] In some embodiments, please refer to Figures 4 to 6 The outer diameter D2 of the third grinding wheel toothed ring 53 is smaller than the outer diameter D1 of the second grinding wheel toothed ring 43, and the third mounting part 51 is the same as the second mounting part 41. Thus, by utilizing the fact that the second mounting part 41 of the second grinding wheel 4 is the same as the third mounting part 51 of the third grinding wheel 5, the second grinding wheel 4 and the third grinding wheel 5 can be detachably connected to the second mounting base 22 connected to the same second spindle 12.

[0039] It should be noted that the third mounting part 51 and the second mounting part 41 can be the same as the mounting part of the second grinding wheel 4 in the prior art. For example, when the first wafer 61 is 8 inches and the second wafer 63 is 6 inches, the third mounting part 51 and the second mounting part 41 can be the same as the mounting part of the Taiko grinding wheel corresponding to the 8-inch wafer in the prior art. That is, the mounting part of the smaller third grinding wheel 5 in the prior art is adjusted to be the same as the mounting part of the larger second grinding wheel 4 in the prior art, so that the second mounting part 41 of the improved second grinding wheel 4 and the third mounting part 51 of the third grinding wheel 5 are the same.

[0040] In some embodiments, please refer to Figure 4 The axial dimension H2 of the second mounting portion 41 is equal to the axial dimension H1 of the second annular portion 42, making the axial structural design of the second grinding wheel 4 more symmetrical. This helps to balance the mass distribution of the second grinding wheel 4, thereby reducing vibration and imbalance during rotation and improving the grinding accuracy of the second grinding wheel 4. Simultaneously, it also helps the second annular portion 42 and the second mounting portion 41 maintain consistent thermal expansion under the thermal environment generated during the thinning process.

[0041] In some embodiments, please refer to Figure 6The axial dimension H4 of the third mounting portion 51 is equal to the axial dimension H3 of the third annular portion 52, making the axial structural design of the third grinding wheel 5 more symmetrical. This helps to balance the mass distribution of the third grinding wheel 5, thereby reducing vibration and imbalance during rotation and improving the grinding accuracy of the third grinding wheel 5. Simultaneously, it also helps the third annular portion 52 and the third mounting portion 51 maintain consistent thermal expansion under the thermal environment generated during the thinning process.

[0042] In some embodiments, please refer to Figure 1 , Figure 4 as well as Figure 6 The axial dimensions H1 of the second annular portion 42 and H3 of the third annular portion 52 are larger than the axial dimension H5 of the first annular portion 32. During the Taiko thinning process of the second grinding wheel 4 and the third grinding wheel 5, the larger axial dimensions H1 of the second annular portion 42 and H3 of the third annular portion 52 create a gap between the mounting portion of the second grinding wheel 4 and the corresponding edge reinforcement portion during the thinning process, allowing abrasive particles generated during the first or second fine grinding thinning process to be discharged through the gap.

[0043] In some embodiments, please refer to Figure 1 and Figure 2 The wafer thinning equipment 100 also includes a nozzle 7, which is located on one side of the second spindle 12. The outlet of the nozzle 7 is configured to face the second grinding wheel ring 43 or the third grinding wheel ring 53 to spray rinsing fluid, thereby washing away the grinding particles generated during the first or second fine grinding thinning process. At the same time, the rinsing fluid also absorbs and dissipates the large amount of heat generated by friction during the thinning process, thereby achieving a cooling effect. Since the difference in size between the outer diameter of the second mounting part 41 and the outer diameter of the second grinding wheel ring 43 is small, it is difficult to set up a flow channel for providing rinsing fluid inside the second mounting part 41. Therefore, the rinsing fluid is sprayed out through an external nozzle 7.

[0044] In some embodiments, the diameter of the first wafer 61 is 8 inches, and the diameter of the second wafer 63 is 6 inches. This minimizes the difference in diameter between the first wafer 61 and the second wafer 63, resulting in a smaller difference in their thinning process parameters and reducing the difficulty of adjusting process parameters when switching between the second grinding wheel 4 and the third grinding wheel 5. Furthermore, when the mounting portion of the third grinding wheel 5 in the prior art is adjusted to be the same as the mounting portion of the second grinding wheel 4 in the prior art, the changes in the third mounting portion 51 of the third grinding wheel 5 before and after the improvement are not significant. The process control method for the second fine grinding and thinning process also changes little or not at all before and after the improvement, further reducing the complexity of adjustments and the difficulty of process control when the wafer thinning equipment 100 performs different Taiko thinning processes. Moreover, during the thinning process of the first wafer 61 and the second wafer 63 using the first grinding wheel 3, the difference between the overlap area between the first grinding wheel 3 and the first wafer 61 and the overlap area between the first grinding wheel 3 and the second wafer 63 is also small, which can improve the utilization rate of the first grinding wheel 3 and increase processing efficiency.

[0045] In some embodiments, the diameter of the first wafer 61 is 12 inches, and the diameter of the second wafer 63 is 8 inches. This results in a smaller difference between the diameters of the first wafer 61 and the second wafer 63, and consequently, a smaller difference in their thinning process parameters. This reduces the difficulty of adjusting process parameters when switching between the second grinding wheel 4 and the third grinding wheel 5, and reduces the complexity of adjusting the wafer thinning equipment 100 when performing different Taiko thinning processes, as well as the difficulty of process control. Furthermore, during the thinning process of the first wafer 61 and the second wafer 63 using the first grinding wheel 3, the difference between the overlap area between the first grinding wheel 3 and the first wafer 61 and the overlap area between the first grinding wheel 3 and the second wafer 63 is also small, which can improve the utilization rate of the first grinding wheel 3 and increase processing efficiency.

[0046] In summary, in the wafer thinning equipment of this application embodiment, the first rough grinding thinning process processes the entire first initial surface of the first wafer to form a first processed surface, also known as conventional full-surface thinning. After the first rough grinding thinning process, the first fine grinding thinning process thins the central region of the first processed surface of the first wafer, also known as Taiko thinning. Thus, the first spindle of the first fine grinding thinning process and the second spindle of the first rough grinding thinning process do not need to be coaxial, reducing the process difficulty of the first fine grinding thinning process and overcoming the problem of high process difficulty caused by requiring the spindles of the two consecutive Taiko thinning processes to remain concentric. Furthermore, the first target thinned wafer is provided with a first recess and includes a first edge reinforcement portion. The first edge reinforcement portion surrounds the first recess and provides local thickening to the first target thinned wafer, facilitating subsequent processing by picking up the first edge reinforcement portion, thus overcoming the problem of easy breakage of the thinned wafer caused by two consecutive conventional full-surface thinning processes. Therefore, the first rough grinding and thinning process combined with the first fine grinding and thinning process reduces the difficulty of thinning the first wafer and also reduces the risk of breakage after the first wafer is thinned.

[0047] Furthermore, if a conventional wafer thinning machine is used for the first rough grinding and thinning process, and then a Taiko wafer thinning machine is used for the first fine grinding and thinning process, at least two wafer thinning machines are required in total. In the embodiments of this application, the first spindle and the second spindle belong to the same wafer thinning machine, which can reduce the number of wafer thinning machines required for continuous conventional thinning and Taiko thinning of the first wafer, and reduce the cost of purchasing and maintaining wafer thinning machines. Moreover, it also eliminates the time required for handling the first wafer when it is subjected to conventional full-surface rough grinding and thinning and Taiko fine grinding and thinning on different wafer thinning machines, shortening the overall thinning time of the first wafer and improving the production efficiency of thinning the first wafer.

[0048] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0049] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0050] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0051] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A wafer thinning device, characterized in that, include: First main axis; Second main axis; The first grinding wheel is configured to be mounted on the first spindle when the wafer thinning equipment is in the first state, and is configured to perform a first rough grinding thinning process on the entire first initial surface of the first wafer to form a first processed surface; The second grinding wheel is configured to be mounted on the second spindle in the first state and configured to perform a first fine grinding thinning process on the central region of the first processing surface to form a first target thinned wafer; wherein the first target thinned wafer is provided with a first recess and includes a first edge reinforcement portion, the first recess is obtained by the first fine grinding thinning process, and the first edge reinforcement portion is located at the edge of the first target thinned wafer and surrounds the first recess.

2. The wafer thinning equipment according to claim 1, characterized in that, The first grinding wheel is also configured to be mounted on the first spindle when the wafer thinning equipment is in the second state, and is configured to perform a second rough grinding thinning process on the entire second initial surface of the second wafer to form a second processed surface; The diameter of the second wafer is smaller than the diameter of the first wafer.

3. The wafer thinning equipment according to claim 2, characterized in that, The first grinding wheel includes a first mounting part, a first grinding wheel tooth ring, and a first annular part. The first grinding wheel is mounted on the first spindle through the first mounting part. The first annular part is located on the first mounting part, and the first grinding wheel tooth ring is located on the first annular part. The first grinding wheel performs the first coarse grinding thinning process or the second coarse grinding thinning process through the first grinding wheel tooth ring. The first mounting part is provided with a first flow channel, and a through hole is provided at the center of the first annular part. The through hole is connected to the outlet of the first flow channel. The outlet of the first flow channel is configured to supply rinsing liquid, which flows out through the through hole to clean the grinding particles generated during the first coarse grinding and thinning process or the second coarse grinding and thinning process.

4. The wafer thinning equipment according to claim 3, characterized in that, The wafer thinning equipment further includes a first mounting base, which is mounted on the first spindle, and the first mounting part of the first grinding wheel is mounted on the first mounting base; The first mounting base is provided with a second flow channel, and the inlet of the second flow channel is configured to connect to the inlet of the first flow channel; The first main shaft is provided with a third flow channel, and the outlet of the third flow channel is configured to connect to the inlet of the second flow channel.

5. The wafer thinning equipment according to claim 2, characterized in that, Also includes: The third grinding wheel is configured to be mounted on the second spindle in the second state and is configured to perform a second fine grinding and thinning process on the central region of the second processing surface to form a second target thinned wafer; The second target thinned wafer is provided with a second recess and includes a second edge reinforcement portion. The second recess is obtained by the second fine grinding thinning process. The second edge reinforcement portion is located at the edge of the second target thinned wafer and surrounds the second recess.

6. The wafer thinning equipment according to claim 5, characterized in that, The thickness of the first edge reinforcement portion along the radial direction of the first target thinned wafer is greater than the thickness of the second edge reinforcement portion along the radial direction of the second target thinned wafer.

7. The wafer thinning equipment according to claim 5, characterized in that, The second grinding wheel includes a second mounting portion, a second annular portion, and a second grinding wheel toothed ring. The second annular portion is located on the second mounting portion, and the second grinding wheel toothed ring is located on the second annular portion. The second grinding wheel is mounted on the second spindle through the second mounting portion. The third grinding wheel includes a third mounting part, a third annular part, and a third grinding wheel toothed ring. The third annular part is located on the third mounting part, and the third grinding wheel toothed ring is located on the third annular part. The outer diameter of the third grinding wheel toothed ring is smaller than the outer diameter of the second grinding wheel toothed ring. The third mounting part is the same as the second mounting part. The third grinding wheel is mounted on the second main shaft through the third mounting part.

8. The wafer thinning apparatus according to claim 7, characterized in that, The axial dimension of the second mounting part is equal to the axial dimension of the second annular part, and the axial dimension of the third mounting part is equal to the axial dimension of the third annular part.

9. The wafer thinning equipment according to claim 2, characterized in that, The first wafer has a diameter of 8 inches, and the second wafer has a diameter of 6 inches.

10. The wafer thinning equipment according to claim 2, characterized in that, The first wafer has a diameter of 12 inches, and the second wafer has a diameter of 8 inches.

Images