Wafer Edge Trimming Machine and Wafer Edge Trimming Method

Abstract

The present invention discloses a wafer trimming machine, a method for trimming a wafer, and a wafer. The wafer trimming machine includes: a carrier for carrying the wafer. The carrier includes a middle region and a peripheral region surrounding the middle region. The center of the wafer coincides with the center of the middle region, and the edge of the wafer is located in the peripheral region; a first cutter head disposed above the peripheral region of the carrier; the first cutter head has a cylindrical shape, and the axis of the first cutter head extends along a first direction, the first direction being parallel to the plane where the carrier is located; and the axis of the first cutter head does not pass through the center of the middle region. This wafer trimming machine is not prone to failure, has a low production design cost, can conveniently switch between trimming processes, and the wafer formed after trimming by this wafer trimming machine has higher quality.

Description

Technical Field

[0001] The present invention relates to the technical field of integrated circuit manufacturing, and in particular, to a wafer trimming machine, a wafer trimming method, and a wafer. Background Art

[0002] To ensure the integrity and smoothness of the wafer edge, it is necessary to perform a trimming process on the wafer. The trimming process is to cut off a specific depth and width circle at the wafer edge with a tool. The tool head of the conventional wafer trimming machine used in the wafer trimming process is usually a cylindrical hollow circle, and the tool head structure is as shown in Figure 6 and Figure 7 shown. The tool head rotates at high speed and contacts the edge of the wafer, thereby removing the edge of the wafer. The relative position of the tool head and the wafer during the trimming process of the conventional trimming machine is as shown in Figures 1 - 3 shown. The axis of the tool head passes through the center of the middle area of the stage, and the relative position of the tool head and the stage is as shown in Figure 4 shown. The edge of the wafer after the trimming process forms a stepped morphology as shown in Figure 5 shown.

[0003] After the wafer is trimmed by the conventional trimming method, the trimming depth is usually about 150um, and the side wall is in a vertical morphology. During the wafer thinning process, the strength of the trimmed wafer edge is low, and it is easy to fall off in advance, resulting in scratching of the wafer, poor roughness, and at the same time, due to the shedding of its residues, the dropped substances are not in a fine powder form, which will cause blockage of the sewage pipe.

[0004] Moreover, after the wafer is trimmed by the conventional trimming method, when using PVD (Physical Vapor Deposition) to deposit the isolation layer and the seed layer, the step coverage of the wafer side wall is too low, resulting in a discontinuous film layer, and there is an abnormal power-on situation in the subsequent process, causing damage to the wafer trimming machine and the wafer.

[0005] In the related art, by replacing the tool head of the wafer trimming machine with a special-shaped tool head, the morphology of the wafer side wall is improved into a ramp morphology, increasing the contact area from top to bottom in the top view, so as to increase the step coverage of the side wall and avoid the phenomenon of discontinuous barrier layer and seed layer. However, this method requires a customized tool head, and due to the high precision of the wafer trimming machine, the motors and transmission devices configured in the wafer trimming machine need to be remade. And when it is necessary to switch back to the conventional trimming process, a series of hardware replacements are required, with a large workload and high processing costs, and there is room for improvement. Summary of the Invention

[0006] The present invention aims to solve at least one of the above technical problems in the prior art to some extent. To this end, the present invention provides a wafer trimming machine tool, which is not prone to failure, has a low production design cost, can conveniently switch between trimming processes, and the wafer formed after trimming by this wafer trimming machine tool has higher quality.

[0007] A wafer trimming machine tool according to an embodiment of the present invention includes: a carrier for carrying a wafer, the carrier including a central region and a peripheral region surrounding the central region, the center of the wafer coinciding with the center of the central region, and the edge of the wafer being located in the peripheral region;

[0008] A first cutter head disposed above the peripheral region of the carrier; the first cutter head has a cylindrical shape, the axis of the first cutter head extends in a first direction, the first direction is parallel to the plane of the carrier; and the axis of the first cutter head does not pass through the center of the central region.

[0009] According to some embodiments of the present invention, the line connecting the first cutter head and the center of the central region is perpendicular to the first direction.

[0010] According to some embodiments of the present invention, the wafer trimming machine tool includes at least two of the first cutter heads, and the at least two first cutter heads are spaced apart along the edge direction of the carrier.

[0011] According to some embodiments of the present invention, at least two of the first cutter heads are disposed on opposite sides of the central region along a second direction;

[0012] The second direction is parallel to the plane of the carrier, and the second direction intersects the first direction.

[0013] According to some embodiments of the present invention, the wafer trimming machine tool further includes a second cutter head, the second cutter head has a cylindrical shape, and the axis of the second cutter head extends along the first direction;

[0014] The axis of the second cutter head passes through the center of the central region.

[0015] The present invention also provides a method for trimming a wafer, the method for trimming a wafer including: placing the wafer on a carrier, the carrier including a central region and a peripheral region surrounding the central region, the center of the wafer coinciding with the center of the central region, and the edge of the wafer being located in the peripheral region;

[0016] The first cutter head is disposed above the peripheral region. The shape of the first cutter head is cylindrical, and the axis of the first cutter head extends in a first direction, which is parallel to the plane where the stage is located. And the axis of the first cutter head does not pass through the center of the middle region;

[0017] The first cutter head performs trimming on the edge of the wafer.

[0018] According to some embodiments of the present invention, the first cutter head is disposed above the peripheral region, and the connection line between the first cutter head and the center of the middle region is perpendicular to the first direction.

[0019] According to some embodiments of the present invention, at least two first cutter heads are disposed above the peripheral region, and along the edge direction of the stage, the at least two first cutter heads are spaced apart.

[0020] According to some embodiments of the present invention, at least two first cutter heads are disposed on opposite sides of the middle region along a second direction;

[0021] The second direction is parallel to the plane where the stage is located, and the second direction intersects the first direction.

[0022] According to another aspect of the present invention, a wafer is obtained by the above trimming method; the side surface of the wafer is an arc surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a front view of a schematic diagram of the relative positions of the cutter head and the wafer during the trimming process of a wafer trimming machine in the related art;

[0024] Figure 2 is a side view of a schematic diagram of the relative positions of the cutter head and the wafer during the trimming process of a wafer trimming machine in the related art;

[0025] Figure 3 is a top view of a schematic diagram of the relative positions of the cutter head and the wafer during the trimming process of a wafer trimming machine in the related art;

[0026] Figure 4 is a schematic diagram of the structure of a wafer trimming machine in the related art;

[0027] Figure 5 is a cross-sectional view of a wafer after being trimmed by a wafer trimming machine in the related art;

[0028] Figure 6 is a cross-sectional view of a cutter head according to an embodiment of the present invention;

[0029] Figure 7 is a schematic diagram of the structure of a cutter head according to an embodiment of the present invention;

[0030] Figure 8 is a schematic structural diagram of a wafer trimming machine according to an embodiment of the present invention;

[0031] Figure 9 is a schematic diagram of the relative positions of the tool head and the wafer during the trimming process of a wafer trimming machine according to an embodiment of the present invention;

[0032] Figure 10 is a front view of a schematic diagram of the relative positions of the tool head and the wafer during the trimming process of a wafer trimming machine according to another embodiment of the present invention;

[0033] Figure 11 is a side view of a schematic diagram of the relative positions of the tool head and the wafer during the trimming process of a wafer trimming machine according to another embodiment of the present invention;

[0034] Figure 12 is a top view of a schematic diagram of the relative positions of the tool head and the wafer during the trimming process of a wafer trimming machine according to another embodiment of the present invention;

[0035] Figure 13 is a schematic structural diagram of a wafer trimming machine according to another embodiment of the present invention;

[0036] Figure 14 is a cross-sectional view of the wafer after trimming by a wafer trimming machine according to another embodiment of the present invention;

[0037] Figure 15 is a schematic structural diagram of a wafer trimming machine according to still another embodiment of the present invention;

[0038] Figure 16 is a flowchart of a method for trimming a wafer according to an embodiment of the present invention.

[0039] Reference numerals:

[0040] Wafer trimming machine 100, carrier 1, center O of the middle region, tool head Z, first tool head Z1, first tool head Z1' whose connection line with the center of the middle region is perpendicular to the first direction, second tool head Z2, wafer 20. Detailed Description of the Embodiment

[0041] The embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0042] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention.

[0043] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0044] In the present invention, unless otherwise clearly specified and defined, terms such as "mounted", "connected", "coupled", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection or capable of communicating with each other; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] In the present invention, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "under" the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the first feature has a lower horizontal height than the second feature.

[0046] Next, reference is made to Figures 1 - 15 Describe a wafer edge trimming machine 100 according to an embodiment of the present invention.

[0047] The wafer edge trimming machine 100 according to an embodiment of the present invention may include: a stage 1 and a tool head Z.

[0048] The stage 1 is used to carry the wafer 20. The stage 1 includes a middle area and a peripheral area surrounding the middle area. The center of the wafer 20 coincides with the center O of the middle area to ensure that the wafer 20 can rotate uniformly as the stage 1 rotates. The edge of the wafer 20 is located in the peripheral area, and the cutter head Z is arranged above the peripheral area of the stage 1. The cutter head Z can be stationary and can trim the edge of the wafer 20 in the peripheral area.

[0049] Alternatively, the stage 1 does not rotate, and the cutter head Z rotates driven by a motor, and the cutter head Z is used to trim the edge of the wafer 20 in the peripheral area.

[0050] Or, the stage 1 drives the wafer 20 to rotate, the cutter head Z rotates driven by a motor, and the cutter head Z contacts the rotating wafer 20 to trim the wafer 20. When the cutter head Z and the wafer 20 rotate simultaneously, their rotation directions can be the same or different.

[0051] To ensure the integrity and smoothness of the edge of the wafer 20, the wafer 20 needs to be trimmed. The trimming process is to cut off a specific depth and width of a circle at the edge of the wafer 20 with a tool. The cutter head Z of the conventional wafer trimming machine tool 100 used in the wafer trimming process is usually a cylindrical hollow circle. The structure of the cutter head Z is as Figure 6 and Figure 7 shown. The cutter head Z can rotate at a high speed and contact the edge of the wafer 20 to remove the edge of the wafer 20. The relative positions of the cutter head Z and the wafer 20 during the trimming process of the conventional wafer trimming machine tool 100 are as Figures 1 - 3 shown. The axis of the cutter head Z passes through the center O of the middle area of the stage 1. The relative position of the cutter head Z and the stage 1 is as Figure 4 shown. After the trimming process, the edge of the wafer 20 forms a stepped morphology as Figure 5 shown.

[0052] After the wafer 20 is trimmed by a conventional trimming method, the trimming depth is usually about 150um, and the side wall is in a vertical morphology. During the thinning process of the wafer 20, the strength at the edge of the trimmed wafer 20 is low, and premature detachment is likely to occur, resulting in scratches on the wafer 20, poor roughness, and at the same time, because its residue falls off, the falling material is not in a fine powder form, which will cause the sewage pipe to be blocked.

[0053] Moreover, after the wafer 20 is trimmed by a conventional trimming method, when using PVD (Physical Vapor Deposition) to deposit the isolation layer and the seed layer, the step coverage of the side wall of the wafer 20 is too low, resulting in discontinuous film layers, and there is an abnormal power-on situation in the subsequent process, causing damage to the wafer trimming machine tool 100 and the wafer 20.

[0054] In the related art, by replacing the cutter head Z of the wafer trimming machine 100 with a special-shaped cutter head Z, the morphology of the side wall of the wafer 20 is improved into a ramp morphology, increasing the contact area from top to bottom in the top view, so as to increase the step coverage rate of the side wall and avoid the phenomenon of discontinuity of the barrier layer and the seed layer. However, this method requires a customized cutter head Z, and due to the high precision of the wafer trimming machine 100, both the motor and the transmission device configured in the wafer trimming machine 100 need to be remade. Moreover, when switching back to the conventional trimming process, a series of hardware replacements are required, with a large workload and high processing costs.

[0055] Therefore, the embodiment of the present invention designs a wafer trimming machine 100 that uses the cutter head Z used in the conventional trimming process for trimming, and the morphology of the side wall of the wafer 20 after trimming is improved into an arc morphology. Thus, the edge of the wafer 20 after trimming has higher strength, the step coverage rate of the side wall is high, the quality of the wafer 20 formed after the wafer trimming machine 100 trims is higher, the wafer trimming machine 100 is not prone to failure, and the motor and the transmission device configured in the wafer trimming machine 100 do not need to be redesigned and remade, reducing the production design cost. The wafer trimming machine 100 can be switched more conveniently between the two trimming processes.

[0056] The cutter head Z of the wafer trimming machine 100 is the first cutter head Z1, and the shape of the first cutter head Z1 is cylindrical. The first cutter head Z1 is the same as the cutter head Z of the conventional wafer trimming machine 100 used for trimming the wafer 20. Therefore, in the embodiment of the present invention, the motor and the transmission device configured in the wafer trimming machine 100 do not need to be remade, reducing the processing cost. The first cutter head Z1 is arranged above the peripheral area of the stage 1 to ensure that the first cutter head Z1 can trim the edge of the wafer 20 arranged in the peripheral area above.

[0057] Wherein, the axis of the first cutter head Z1 extends along the first direction, the first direction is parallel to the plane where the stage 1 is located, and the axis of the first cutter head Z1 does not pass through the center O of the middle area of the stage 1. Thus, after the first cutter head Z1 trims the wafer 20, the morphology of the side wall of the formed wafer 20 is an arc morphology, increasing the contact area with the surface of the wafer 20 from top to bottom in the top view direction, increasing the step coverage rate of the side wall of the wafer 20 after trimming, avoiding the phenomenon of discontinuity of the barrier layer and the seed layer, and the edge of the wafer 20 after trimming has high strength, and the edge of the wafer 20 is not prone to premature shedding during the thinning process. This not only improves the quality of the wafer 20, but also reduces the possibility of blockage of the sewage pipe caused by the substances falling during the trimming process.

[0058] Specifically, the twelve o'clock direction and the six o'clock direction on the stage 1 are parallel to the first direction, and the axis of the first cutter head Z1 does not pass through the center O of the middle area of the stage 1, that is, the first cutter head Z1 is arranged in any direction of the stage 1 except the twelve o'clock direction and the six o'clock direction.

[0059] According to the wafer trimming machine table 100 of the embodiment of the present invention, the wafer trimming machine table 100 is not prone to failure, has a low production design cost, can be conveniently switched between trimming processes, and the quality of the wafer 20 formed after trimming by the wafer trimming machine table 100 is higher.

[0060] In some embodiments, the connection line between the first cutter head Z1 and the center O of the middle area is not perpendicular to the first direction. At this time, the relative positions of the cutter head Z and the wafer 20 during the trimming process of the wafer trimming machine table 100 are as Figure 9 shown, and the relative position of the cutter head Z and the stage 1 is as Figure 8 shown. After the first cutter head Z1 arranged at this position trims the wafer 20, the side wall of the formed wafer 20 has an arc-shaped morphology, which increases the contact area with the surface of the wafer 20 from top to bottom in the top view direction, increases the step coverage rate of the side wall of the trimmed wafer 20, and the inclination of the side wall of the wafer 20, and avoids the phenomenon of discontinuity of the barrier layer and the seed layer.

[0061] In other embodiments, the connection line between the first cutter head Z1' and the center O of the middle area is perpendicular to the first direction. At this time, the relative positions of the cutter head Z' and the wafer 20 during the trimming process of the wafer trimming machine table 100 are as Figures 10 - 12 shown, and the relative position of the cutter head Z' and the stage 1 is as Figure 8 and Figure 13 shown. The twelve o'clock direction and the six o'clock direction on the stage 1 are parallel to the first direction, and the connection line between the first cutter head Z1' and the center O of the middle area is perpendicular to the first direction, that is, the first cutter head Z1' is arranged in the twelve o'clock direction and the six o'clock direction of the stage 1. The pressure received by the first cutter head Z1' arranged at this position is the smallest during the trimming process, which is beneficial to improving the service life of the cutter head Z. After the first cutter head Z1' trims the wafer 20, the side wall of the formed wafer 20 has an arc-shaped morphology, and the morphology of the wafer 20 is as Figure 14 shown, which increases the contact area with the surface of the wafer 20 from top to bottom in the top view direction, increases the step coverage rate of the side wall of the trimmed wafer 20, and the inclination of the side wall of the wafer 20, and avoids the phenomenon of discontinuity of the barrier layer and the seed layer.

[0062] As Figure 13As shown, the wafer trimming machine 100 includes at least two first cutting heads Z1. Along the edge direction of the stage 1, the at least two first cutting heads Z1 are spaced apart. Among them, the two first cutting heads Z1 can respectively implement different trimming processes or the two first cutting heads Z1 can simultaneously complete different steps of a trimming process.

[0063] In some embodiments, referring to Figure 13 , the second direction is parallel to the plane where the stage 1 is located, and the second direction intersects the first direction. At least two first cutting heads Z1 are disposed on opposite sides of the middle region along the second direction. At this time, the shapes of the wafers 20 formed after trimming by any one of the two first cutting heads Z1 are the same. Therefore, the two first cutting heads Z1 can simultaneously complete different steps of a trimming process.

[0064] As Figure 15 shown, when performing deep hole electroplating, the insulating layer and the seed layer of the wafer 20 become correspondingly thicker. At this time, the trimming of the wafer 20 needs to be performed by a conventional trimming method, that is, the wafer 20 is trimmed by a cylindrical cutting head Z whose axis passes through the center O of the middle region of the stage 1. In order to enable the same wafer trimming machine 100 to simultaneously implement two different trimming processes, the wafer trimming machine 100 further includes a second cutting head Z2. The shape of the second cutting head Z2 is cylindrical, that is, the second cutting head Z2 has the same shape as the first cutting head Z1 and is both cylindrical. The axis of the second cutting head Z2 extends along the first direction and passes through the center O of the middle region. The three o'clock direction and the nine o'clock direction on the stage 1 are parallel to the first direction. The axis of the second cutting head Z2 extends along the first direction and passes through the center O of the middle region, that is, the second cutting head Z2 is disposed at the three o'clock direction or the nine o'clock direction of the stage 1.

[0065] That is to say, the first cutting head Z1 and the second cutting head Z2 are simultaneously integrated on the wafer trimming machine 100. Among them, the first cutting head Z1 can implement the first trimming process. The morphology of the side wall of the wafer 20 after trimming is an arc surface morphology. The trimmed wafer 20 can adopt a copper electroplating process with a relatively thin thickness. The second cutting head Z2 can implement the second conventional trimming process. The morphology of the side wall of the wafer 20 after trimming is a step morphology. The wafer trimming machine 100 has stronger functionality and reduces the production cost during the trimming process of the wafer 20.

[0066] The present invention also proposes a method for trimming a wafer 20. As Figure 16 shown, the method for trimming the wafer 20 includes the following steps:

[0067] S1, placing the wafer 20 on the stage 1;

[0068] Specifically, the stage 1 includes a middle region and a peripheral region surrounding the middle region. The center of the wafer 20 coincides with the center O of the middle region, and the edge of the wafer 20 is located in the peripheral region. Herein, the stage 1 is used to carry the wafer 20. The stage 1 includes a middle region and a peripheral region surrounding the middle region. The center of the wafer 20 coincides with the center O of the middle region to ensure that the wafer 20 can rotate uniformly as the stage 1 rotates, or the cutter head Z can rotate uniformly and stably around the wafer 20, so that the cutter head Z can perform uniform trimming on the edge of the wafer 20 in the subsequent trimming step.

[0069] S2. Set the first cutter head Z1 above the peripheral region.

[0070] Specifically, the edge of the wafer 20 is located in the peripheral region, and the cutter head Z is set above the peripheral region of the stage 1 to ensure that the cutter head Z can perform trimming on the edge of the wafer 20 in the peripheral region.

[0071] Wherein, the shape of the first cutter head Z1 is cylindrical. The cylindrical cutter head Z is the cutter head Z used in the conventional trimming process of the wafer 20. Therefore, the motor and transmission device configured in the wafer trimming machine 100 do not need to be redesigned and customized, reducing the production design cost, and the two trimming processes can be switched more conveniently.

[0072] The axis of the first cutter head Z1 extends along a first direction. The first direction is parallel to the plane where the stage 1 is located, and the axis of the first cutter head Z1 does not pass through the center O of the middle region. Thus, the maximum cross-section of the shape of the first cutter head Z1 invading the interior of the wafer 20 in the radial direction of the wafer 20 is formed as an arc. Therefore, after the first cutter performs trimming on the edge of the wafer 20, the morphology of the side wall of the formed wafer 20 is an arc morphology, increasing the contact area with the surface of the wafer 20 from top to bottom in the top view direction, increasing the step coverage rate of the side wall of the wafer 20 after trimming, avoiding the phenomenon of discontinuity of the barrier layer and the seed layer, having a high strength at the edge of the wafer 20 after trimming, and the edge of the wafer 20 is not prone to premature detachment during the thinning process, not only improving the quality of the wafer 20, but also reducing the possibility of blockage of the sewage pipe caused by the substances falling during the trimming process.

[0073] In some embodiments, the connection line between the first cutter head Z1 and the center O of the middle region is not perpendicular to the first direction. At this time, the relative positions of the first cutter head Z1 and the wafer 20 during the trimming process are as Figure 9 shown, and the relative position of the first cutter head Z1 and the stage 1 is as Figure 8As shown, after the first cutter head Z1 disposed at this position performs trimming on the wafer 20, the sidewall of the wafer 20 formed has an arc-shaped morphology, which increases the contact area with the surface of the wafer 20 from top to bottom in the top view direction, increases the step coverage rate of the sidewall of the wafer 20 after trimming, and the inclination of the sidewall of the wafer 20, and avoids the occurrence of discontinuity of the barrier layer and the seed layer.

[0074] In some other embodiments, the line connecting the first cutter head Z1' and the center O of the middle region is perpendicular to the first direction. At this time, during the trimming process, the relative positions of the first cutter head Z1' and the wafer 20 are as Figures 10 - 12 shown, and the relative position of the first cutter head Z1' and the stage 1 is as Figure 8 and Figure 13 shown. The pressure received by the first cutter head Z1' disposed at this position is the smallest during the trimming process, which is beneficial to improving the service life of the first cutter head Z1'. After the first cutter head Z1' performs trimming on the wafer 20, the sidewall of the wafer 20 formed has an arc-shaped morphology, and the morphology of the wafer 20 is as Figure 14 shown, which increases the contact area with the surface of the wafer 20 from top to bottom in the top view direction, increases the step coverage rate of the sidewall of the wafer 20 after trimming, and the inclination of the sidewall of the wafer 20, and avoids the occurrence of discontinuity of the barrier layer and the seed layer.

[0075] S3, the first cutter head Z1 trims the edge of the wafer 20.

[0076] Among them, the stage 1 drives the wafer 20 to rotate, and the first cutter head Z1 contacts the rotating wafer 20 to perform trimming on the wafer 20, and / or the first cutter head Z1 rotates around the wafer 20 under the drive of the motor and contacts the wafer 20 to perform trimming on the wafer 20. Among them, when the first cutter head Z1 and the wafer 20 rotate simultaneously, their rotation directions can be the same or different.

[0077] The vertical feed amount of the cutter head Z should not exceed the radius of the cutter head Z, and the radial feed amount of the cutter head Z should not exceed the radius of the cutter head Z to avoid too low local structural strength of the wafer 20 after trimming and affecting the quality of the wafer 20.

[0078] In some other embodiments, the trimming method of the wafer 20 includes the following steps:

[0079] S1, place the wafer 20 on the stage 1.

[0080] S2, dispose at least two first cutter heads Z1 above the peripheral region.

[0081] Specifically, along the edge direction of the stage 1, at least two first cutting heads Z1 are arranged at intervals, and the two first cutting heads Z1 can respectively implement different trimming processes or the two first cutting heads Z1 can simultaneously complete different steps of a trimming process.

[0082] S3. Select one of the two first cutting heads Z1 to perform trimming on the edge of the wafer 20.

[0083] Specifically, select one of the two first cutting heads Z1 as needed to perform trimming on the edge of the wafer 20.

[0084] In some embodiments, at least two first cutting heads Z1 are arranged on opposite sides along the second direction in the middle region. The second direction is parallel to the plane where the stage 1 is located and intersects with the first direction. At this time, the shapes formed after trimming the wafer 20 by any one of the two first cutting heads Z1 are the same. Therefore, the two first cutting heads Z1 can complete trimming simultaneously.

[0085] Or, the two first cutting heads Z1 can simultaneously complete different steps of a trimming process. For example, select one to perform primary trimming and the other to perform secondary trimming.

[0086] Or, select any one of the two first cutting heads Z1 to perform trimming on the edge of the wafer 20.

[0087] In some other embodiments, the shape formed after trimming the wafer 20 by any one of the two first cutting heads Z1 is different from the shape formed after trimming by the other first cutting head Z1. At this time, one of the two first cutting heads Z1 can be selected as needed to perform trimming on the edge of the wafer 20.

[0088] In still some other embodiments, the trimming method of the wafer 20 includes the following steps:

[0089] S1. Place the wafer 20 on the stage 1.

[0090] S2. Arrange a first cutting head Z1 and a second cutting head Z2 above the peripheral area.

[0091] Specifically, as Figure 15 shown, when performing deep hole electroplating, the insulating layer and the seed layer of the wafer 20 become thicker correspondingly. At this time, the trimming of the wafer 20 needs to be carried out by using a conventional trimming method, that is, trimming the wafer 20 with a cylindrical cutting head Z whose axis passes through the center O of the middle region of the stage 1. Arranging a first cutting head Z1 and a second cutting head Z2 above the peripheral area simultaneously can realize two different trimming processes at the same time. The shape of the second cutting head Z2 is cylindrical, and the axis of the second cutting head Z2 extends along the first direction and passes through the center O of the middle region.

[0092] Among them, the first cutting head Z1 can implement the first trimming process. After trimming, the morphology of the side wall of the wafer 20 is an arc-shaped morphology. The wafer 20 after trimming can adopt a copper electroplating process with a relatively thin thickness. The second cutting head Z2 can implement the second conventional trimming process. After trimming, the morphology of the side wall of the wafer 20 is a stepped morphology.

[0093] S3. Select the first cutting head Z1 or the second cutting head Z2 according to the structure of the wafer 20.

[0094] S42. Use the selected cutting head Z to trim the edge of the wafer 20.

[0095] The present invention also provides a wafer 20 obtained by the above trimming method. For the wafer 20 obtained by the above trimming method, the side surface of the wafer 20 is an arc surface, which increases the contact area with the surface of the wafer 20 from top to bottom in the top view direction, increases the step coverage rate of the side wall, avoids the phenomenon of discontinuity of the barrier layer and the seed layer, the strength of the edge of the wafer 20 is high, the edge of the wafer 20 is not prone to premature detachment during the thinning process, and the quality of the wafer 20 is higher.

[0096] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification.

[0097] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A wafer trimming machine, characterized in that: include: A carrier, used for carrying a wafer, the carrier comprising a middle area and a peripheral area surrounding the middle area, the center of the wafer coincides with the center of the middle area, and the edge of the wafer is located in the peripheral area; A first cutting head is arranged above the peripheral area of ​​the carrier; the first cutting head is cylindrical in shape, the axis of the first cutting head extends along a first direction, the first direction is parallel to the plane where the carrier is located; and the axis of the first cutting head does not pass through the center of the middle area; A line connecting the first cutting head and the center of the middle area is not perpendicular to the first direction, and the first cutting head performs trimming processing on the edge of the wafer, so that the side wall of the wafer has an arc shape; The wafer trimming machine comprises at least two of the first cutting heads, and along the edge direction of the carrier, at least two of the first cutting heads are arranged at intervals; At least two of the first cutting heads are arranged on opposite sides of the middle area along the second direction; The second direction is parallel to the plane where the carrier is located, and the second direction intersects with the first direction.

2. The wafer trimming machine according to claim 1, characterized in that: The wafer trimming machine further includes a second cutter head, the second cutter head is cylindrical in shape, and the axis of the second cutter head extends along the first direction; The axis of the second cutting head passes through the center of the middle area.

3. A wafer trimming method, characterized in that: include: Placing a wafer on a carrier, wherein the carrier includes a middle area and a peripheral area surrounding the middle area, the center of the wafer coincides with the center of the middle area, and the edge of the wafer is located in the peripheral area; The first cutting head is arranged above the peripheral area, the first cutting head is cylindrical in shape, the axis of the first cutting head extends along a first direction, the first direction is parallel to the plane where the carrier is located; and the axis of the first cutting head does not pass through the center of the middle area; The first cutter head performs trimming processing on the edge of the wafer, so that the side wall of the wafer has an arc shape; The first cutting head is arranged above the peripheral area, and a line connecting the first cutting head and the center of the middle area is not perpendicular to the first direction; Disposing at least two of the first cutting heads above the peripheral area, and at least two of the first cutting heads are spaced apart along the edge direction of the carrier; Disposing at least two of the first cutting heads at opposite sides of the middle area along the second direction; The second direction is parallel to the plane where the carrier is located, and the second direction intersects with the first direction.

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