Device, equipment, silicon wafer for wire cutting silicon rod and manufacturing method thereof

Abstract

Embodiments of the present invention disclose a device, equipment, silicon wafers and a manufacturing method thereof for wire-cutting silicon rods. The device includes: a spool body; a guiding module disposed on the circumferential surface of the spool body, the guiding module including a plurality of guiding grooves that are parallel to and spaced apart from each other, for a cutting wire to wind around to form an array composed of a plurality of parallel cutting wire segments, and the array is used to cut a silicon rod into a plurality of silicon wafers at one time by moving along the extending direction of the cutting wire; wherein, the guiding module includes a tension adjusting section, and the tension adjusting section is configured to be able to drive the cutting wire segment wound on the tension adjusting section to deflect away from and towards the spool body together during the wire-cutting operation, so as to adjust the actual tension of the cutting wire segment to a target tension.

Description

Technical Field

[0001] Embodiments of the present invention relate to the technical field of wafer processing, and particularly to a device, equipment, silicon wafer and a manufacturing method thereof for wire cutting a silicon rod. Background Art

[0002] As a carrier for semiconductor circuit processes, the quality of a silicon wafer has a decisive impact on the formation of integrated circuits. Currently, the main processes in the preliminary forming process of a silicon wafer include: silicon rod cutting, physical and chemical grinding, chemical etching, physical and chemical polishing, etc. Silicon rod cutting is one of the core processes in the silicon wafer forming process, which mainly includes multi-wire slurry (SiC) cutting and internal circle cutting. Taking the forming of a 12-inch wafer as an example, the current mainstream process is multi-wire cutting, because compared with internal circle cutting, multi-wire cutting has advantages such as high efficiency, good quality, and high wafer yield.

[0003] Multi-wire cutting is an advanced slicing processing technology at present. Its principle is to wind the cutting wire around a set of wire reels to form an array of cutting wire segments, and use the high-speed reciprocating motion of the cutting wire to bring abrasive into the processing area of the material to be cut (such as a silicon rod) for grinding, while the workpiece to be cut realizes vertical feeding through the lifting of the workbench, so as to cut the workpiece into several thin slices (such as wafers) of the required size and shape at the same time. Usually, the abrasive used in the multi-wire cutting process is preferably slurry, which can not only help grinding, but also play a cooling role in the multi-wire cutting process.

[0004] As the cutting process continues, the position where the silicon rod is cut changes, the force borne by the cutting wire changes, and correspondingly, the magnitude of the cutting wire tension also changes. The magnitude of the cutting wire tension has a direct impact on the surface quality of the cut silicon wafer and the service life of the cutting wire, etc. Therefore, the cutting wire tension should be adjusted in real time during the cutting process. Summary of the Invention

[0005] In view of this, embodiments of the present invention are expected to provide a device, equipment, silicon wafer and a manufacturing method thereof for wire cutting a silicon rod; which can adjust the tension of the cutting wire during the cutting process, improve the flatness and surface quality of the cut silicon wafer, and extend the service life of the cutting wire.

[0006] The technical solution of the embodiments of the present invention is realized as follows:

[0007] In a first aspect, embodiments of the present invention provide a device for wire cutting a silicon rod, the device comprising:

[0008] A wire reel body;

[0009] A guiding module disposed on the circumferential surface of the spool body, the guiding module including a plurality of guiding grooves parallel to and spaced apart from each other for a cutting wire to wind around to form an array composed of a plurality of parallel cutting wire segments, and the array being used to cut a silicon rod into a plurality of silicon wafers at one time by moving along the extending direction of the cutting wire;

[0010] Wherein, the guiding module includes a tension adjusting section, and the tension adjusting section is configured to be able to drive the cutting wire segment wound on the tension adjusting section to move away from and towards the spool body together during the wire cutting operation, so as to adjust the actual tension of the cutting wire segment to a target tension.

[0011] In a second aspect, an embodiment of the present invention provides a device for wire cutting a silicon rod, the device including:

[0012] The device for wire cutting a silicon rod according to the first aspect;

[0013] A carrying unit for loading and fixing the silicon rod to be processed;

[0014] A movement control unit for controlling the movement of the device for wire cutting a silicon rod and / or the carrying unit, so that the device for wire cutting a silicon rod and the carrying unit move towards each other to cut the silicon rod.

[0015] In a third aspect, an embodiment of the present invention provides a method for manufacturing a silicon wafer, the method including:

[0016] Manufacturing a silicon wafer by using the device for wire cutting a silicon rod according to the third aspect, including the following steps:

[0017] Loading and fixing the silicon rod through the carrying unit;

[0018] Controlling the device for wire cutting a silicon rod and the carrying unit loaded with and fixed the silicon rod to move towards each other to cut the silicon rod through the movement control unit;

[0019] Cleaning and detecting the silicon wafers obtained after cutting the silicon rod.

[0020] In a fourth aspect, an embodiment of the present invention provides a silicon wafer obtained by using the device for wire cutting a silicon rod according to the second aspect.

[0021] An embodiment of the present invention provides a device for wire-cutting silicon rods; the device includes a spool body and a guiding module provided on the circumferential surface of the spool body, and the guiding module includes a tension adjusting section; during wire cutting, the span of the cutting wire segment is adjusted by driving the cutting wire segment to deviate away from and towards the spool body by the tension adjusting section, so that the tension of the cutting wire segment is adjusted. Based on this, the tension of the cutting wire segment can be adaptively adjusted according to the change of the cutting situation, and the tension of the cutting wire segment is maintained within an appropriate range, thereby improving the flatness and surface quality of the silicon wafers cut by wire cutting, and avoiding the situation of wire breakage caused by excessive tension of the cutting wire segment. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 FIG. is a schematic diagram of a conventional wire cutting device provided by an embodiment of the present invention;

[0023] Figure 2 FIG. is a schematic diagram of another conventional wire cutting device provided by an embodiment of the present invention;

[0024] Figure 3 FIG. is a schematic diagram of a device for wire-cutting silicon rods provided by an embodiment of the present invention;

[0025] Figure 4 FIG. is a structural schematic diagram of a device for wire-cutting silicon rods provided by an embodiment of the present invention;

[0026] Figure 5 FIG. is a schematic diagram of a device for wire-cutting silicon rods provided by another embodiment of the present invention;

[0027] Figure 6 FIG. is a schematic diagram of a device for wire-cutting silicon rods provided by still another embodiment of the present invention;

[0028] Figure 7 FIG. is a schematic diagram of a device for wire-cutting silicon rods provided by an embodiment of the present invention;

[0029] Figure 8 FIG. is a flowchart of a method for manufacturing silicon wafers provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0031] Refer to Figure 1 , which shows a schematic diagram of a conventional wire cutting device 1. It can be understood that Figure 1 the structure shown is only for illustrative purposes of the principle, and does not mean that those skilled in the art will not add or subtract components based on the specific implementation state on Figure 1 the shown composition structure. The embodiments of the present invention do not make specific limitations in this regard.Figure 1 As shown, the wire cutting device 1 may include a wire cutting unit 11 and a carrying unit 12; in some examples, the wire cutting unit 11 may be placed vertically below the carrying unit 12 as shown in Figure 1 , or may be placed vertically above the carrying unit 12 in some examples as shown in Figure 2 . Specifically, the wire cutting unit 11 may include a plurality of wire spools 111 and a cutting wire 112, and the cutting wire 112 is wound around the wire spools 111 to form an array composed of parallel cutting line segments; in Figure 1 , the number of wire spools 111 is taken as an example of 2, and the reciprocating movement directions of the wire spools 111 and the cutting wire 112 towards and away from the carrying unit 12 are as shown by the solid arrows in Figure 1 , and the reciprocating movement speed may be exemplarily 10 m / s to 15 m / s. The carrying unit 12 is used to load and fix the silicon rod 2 to be processed. In the examples shown in Figure 1 and Figure 2 , the carrying unit 12 may include a base 121 and an intermediate member 122, and the intermediate member 122 may fix the silicon rod 2 to be processed to the base 121. For example, the silicon rod to be processed may be fixed to the lower surface ( Figure 1 ) or the upper surface ( Figure 2 ) of the base through its circumferential surface by using resin.

[0032] For Figure 1 , 2 in the shown wire cutting device 1, the wire cutting unit 11 or the carrying unit 12 can be moved to make the cutting wire 112 and the silicon rod 2 to be processed move towards each other in the vertical direction. After the cutting wire 112 contacts the silicon rod 2 to be processed, the cutting of the silicon rod 2 to be processed is realized by the movement of the cutting wire 112 along its extending direction. In the example shown in Figure 1 , the wire cutting unit 11 can be moved along the direction shown by the black arrow, or the carrying unit 12 can be moved along the direction of the dotted white arrow to realize the movement of the cutting wire 112 and the silicon rod 2 to be processed towards each other in the vertical direction. In the example shown in Figure 2 , the carrying unit 12 can be moved along the direction shown by the black arrow, or the wire cutting unit 11 can be moved along the direction of the dotted white arrow to realize the movement of the cutting wire 112 and the silicon rod 2 to be processed towards each other in the vertical direction. It should be noted that in the embodiments of the present invention, the movement of the wire cutting unit 11 or the carrying unit 12 is realized by installing a lifting device (not shown in the figure). It can be understood that those skilled in the art can also realize the movement of the wire cutting unit 11 or the carrying unit 12 by other means according to actual needs and implementation scenarios, and the embodiments of the present invention will not elaborate on this.

[0033] In a conventional solution, a plurality of guiding grooves for guiding the cutting wire 112 are provided on the spool 111. The guiding grooves are spaced apart from each other at uniform intervals, that is, the spacing between adjacent guiding grooves is consistent. The cutting wire 112 is wound around each guiding groove of each spool 111 in sequence such that the cutting wire 112 is formed into an array composed of a plurality of cutting line segments. In this array, the cutting line segments are parallel to each other so as to cut a silicon rod into a plurality of silicon wafers at one time.

[0034] During wire cutting, the control of the tension of the cutting line segments is closely related to whether the wire cutting process can proceed smoothly and the processing quality, and is one of the core elements of the cutting process. If not properly controlled, obvious wire marks will be formed on the surface of the cut silicon wafers, the silicon wafers will be chipped, and even the wire will break. Specifically, if the tension of the cutting line segments is too large, it will be difficult for the silicon carbide particles attached to the cutting wire to enter the cutting area, reducing the cutting efficiency and forming obvious wire marks. In a more serious case, the cutting wire will break, forcing the wire cutting process to be interrupted; if the tension of the cutting line segments is too small, it may cause the cutting wire to generate low-frequency vibrations, and at the same time increase the curvature of the cutting wire, resulting in a decrease in the sand-carrying ability, so the cutting ability is reduced, and it also affects the surface processing quality of the silicon wafers, making the warpage of the cut silicon wafers larger. It should be particularly noted that in different stages of a single wire cutting process, due to different cutting positions, the required tension of the cutting line segments is also different.

[0035] Based on the above situation, embodiments of the present invention are expected to provide a device, equipment, silicon wafers, and a manufacturing method thereof for wire cutting a silicon rod, which can adjust the tension of the cutting wire during the cutting process, improve the flatness and surface quality of the cut silicon wafers, and extend the service life of the cutting wire.

[0036] For this, refer to Figure 3 , which shows a device 200 for wire cutting a silicon rod provided by an embodiment of the present invention. The device 200 includes:

[0037] A spool body 201;

[0038] A guiding module 202 provided on the circumferential surface 201a of the spool body 201. The guiding module 202 includes a plurality of guiding grooves GG that are parallel and spaced apart from each other, and are used for the cutting wire 112 to wind around to form an array AR composed of a plurality of parallel cutting line segments SE. The array AR is used to cut a silicon rod 2 into a plurality of silicon wafers at one time by moving along the extending direction of the cutting wire 112;

[0039] Among them, the guiding module includes a tension adjusting section 2021, which is configured to drive the cutting wire segment SE wound around the tension adjusting section 2021 to deflect away from and towards the spool body 201 during the wire cutting operation, so as to adjust the actual tension of the cutting wire segment SE to the target tension.

[0040] As Figure 3 shown, the device 200 provided by an embodiment of the present invention includes a spool body 201 and a guiding module 202 provided on the circumferential surface 201a of the spool body 201. Among them, a guiding groove GG is formed on the guiding module 202. In Figure 3 the illustrated embodiment, the guiding module 202 is formed in a cylindrical shape sleeved on the spool body 201, and a part of the circumference of the guiding module 202 constitutes the tension adjusting section 2021. Thus, the guiding module 202 can be divided into two parts, one part is fixed on the circumferential surface 201a of the spool body 201, and the other part can deflect in the direction towards and away from the spool body 201. For example, when the tension adjusting section 2021 deflects away from the spool body 201, the cutting wire segment is also lifted by the tension adjusting section 2021 and away from the spool body 201, the span of the cutting wire segment increases, so it is tightened and the tension also increases; on the contrary, when the tension adjusting section 2021 deflects towards the spool body 201, the cutting wire segment also approaches the spool body 201 with the tension adjusting section 2021, the span of the cutting wire segment decreases, so it is relaxed and the tension also decreases. It should be noted that the target tension can be an ideal tension determined according to actual production experience, which can be a numerical range, and for different cutting conditions, the target tension can be different. For example, for different cutting positions of the same silicon rod, silicon rods of different sizes, different cutting fluid states, etc., the numerical range of the target tension is also different. When using the device 200, the deflection of the tension adjusting section 2021 can be adjusted in real time according to the target tension to achieve the adjustment of the actual tension.

[0041] An embodiment of the present invention provides a device 200 for wire cutting a silicon rod; the device 200 includes a spool body 201 and a guiding module 202 provided on the circumferential surface of the spool body 201, and the guiding module 202 includes a tension adjusting section 2021; during wire cutting, the span of the cutting wire segment SE is adjusted by driving the cutting wire segment SE to deflect away from and towards the spool body by the tension adjusting section 2021, so the tension of the cutting wire segment is adjusted. Based on this, the tension of the cutting wire segment can be adaptively adjusted according to the change of the cutting situation, and the tension of the cutting wire segment is maintained within an appropriate range, so as to improve the flatness and surface quality of the silicon wafer cut by wire cutting, and avoid the situation of wire breakage caused by excessive tension of the cutting wire segment.

[0042] For the specific implementation form of the tension adjustment section, preferably, refer to Figure 4 , the tension adjustment section 2021 is in an arc shape, and one end of the tension adjustment section 2021 is connected to the spool body 201 through a hinge 203, so that the tension adjustment section 2021 can rotate around the hinge 203 in directions away from and towards the spool body 201. In Figure 4 , a part of the guiding module 202 constitutes the tension adjustment section 2021, while another part is integrally formed with the spool body 201. The tension adjustment section 2021 is connected to the other part of the guiding module 202 through the hinge 203, and thus is connected to the spool body 201. Of course, it can be envisaged that the hinge 203 can be directly provided on the spool body 201, so that the tension adjustment section 2021 can be directly connected to the spool body 201 through the hinge 203.

[0043] In Figure 4 , the tension adjustment section 2021 is constituted by a half circumference of the guiding module 202 and is provided on the right side of the spool body. The tension adjustment section 2021 includes a connecting end 2021a and a free end 2021b. The connecting end 2021a is connected to the spool body 201 through the hinge 203. The entire tension adjustment section 2021 can rotate away from the spool body 201 in the clockwise direction around the hinge 203, or can rotate towards the spool body 201 in the counterclockwise direction around the hinge 203. Correspondingly, it can drive the cutting wire segment wound on the tension adjustment section 2021 to offset away from and towards the spool body 201, so as to tighten or loosen the cutting wire segment to change the tension of the cutting wire segment.

[0044] For the same wire cutting device, one or two devices 200 can be provided. As Figure 3 shown, taking the case where two devices 200 are provided as an example, the two devices 200 are symmetrically arranged about the silicon rod in the horizontal direction. Among them, the two tension adjustment sections 2021 are also symmetrically arranged. Thus, the tension of the cutting wire segment can be adjusted by synchronous offset.

[0045] In order to realize the supporting ability of the tension adjustment section 2021 for the cutting wire segment and reduce the wear on the cutting wire segment, preferably, the tension adjustment section 2021 includes a metal base 2022 and a resin part 2023 provided on the upper surface of the metal base. Among them, the guiding groove GG is formed by the resin part 2023. Through the metal base 2022, the tension adjustment section 2021 has the ability to independently support the cutting wire segment, while the resin part 2023 avoids direct contact between the metal base and the cutting wire segment, reducing the wear on the cutting wire segment.

[0046] Since the resin part 2023 is a wearable part, preferably, the resin part is detachably arranged on the metal base. In this way, once the resin part is worn and can no longer guide the cutting line segment, it can be removed and replaced with a new resin part. As a non-limiting example, the resin part 2023 can be bonded to the metal base.

[0047] According to a preferred embodiment of the present invention, as Figure 5 shown, the device further includes a detection module 204 for detecting the actual tension of the cutting line segment. As discussed above, during the wire cutting process, the actual tension of the cutting line segment changes, and it is not necessary to adjust the tension of the cutting line segment throughout the process. By providing the detection module 204, it is possible to determine whether a tension adjustment operation needs to be performed based on the detection result of the detection module 204 and determine the adjustment amount.

[0048] According to another preferred embodiment of the present invention, as Figure 6 shown, the device further includes a control module 205 in communication with the detection module 204 for controlling the offset of the tension adjustment section 2021 according to the detection result of the detection module 204. For example, the control module 205 is an electric control module, which is connected to the hinge 203, and controls the deviation amount of the tension adjustment section 2021 by controlling the rotation amount of the hinge 203. Moreover, the control module 205 can also control the hinge 203 to maintain a certain angle, so that the tension adjustment section 2021 can be maintained at the corresponding offset position and can always support the cutting line segment.

[0049] In order to achieve automatic and precise adjustment of the tension of the cutting line segment, according to still another preferred embodiment of the present invention, as Figure 6 shown, the device 200 includes a processing module 206 in communication with the detection module 204 and the control module 205. The processing module 206 is used to obtain the offset amount of the tension adjustment section 2021 according to the detection result of the detection module 204 and the target tension, and send the offset amount to the control module 205. The control module 205 controls the offset of the tension adjustment section 2021 based on the offset amount.

[0050] Referring to Figure 7 , an embodiment of the present invention further provides a device CD for wire cutting silicon rods, and the device CD includes:

[0051] The device 200 for wire cutting silicon rods according to the above;

[0052] A carrying unit 12 for loading and fixing the silicon rod to be processed;

[0053] The movement control module 13 is configured to control the movement of the device 200 and / or the carrier unit 12, so that the device and the carrier unit move towards each other to cut the silicon rod.

[0054] See Figure 8 , an embodiment of the present invention further provides a method for manufacturing a silicon wafer, the method comprising:

[0055] Manufacturing a silicon wafer by using the wire sawing equipment CD for silicon wafers according to the above, including the following steps:

[0056] S01. Loading and fixing a silicon rod by a carrier unit;

[0057] S02. Controlling the device for wire sawing the silicon rod and the carrier unit loaded with and fixed the silicon rod to move towards each other by a movement control unit to cut the silicon rod;

[0058] S03. Cleaning and detecting the silicon wafer obtained after cutting the silicon rod.

[0059] An embodiment of the present invention further provides a silicon wafer (not shown in the figure), the silicon wafer is obtained by using the wire sawing equipment CD for silicon rods according to the above, and the silicon wafer obtained by the equipment CD has better quality compared with the silicon wafers obtained by conventional equipment, in particular, has fewer cutting line marks on the surface and a small degree of warpage.

[0060] It should be noted that: among the technical solutions described in the embodiments of the present invention, they can be arbitrarily combined without conflict.

[0061] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of changes or substitutions, which should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A device for wire-cutting silicon rods, characterized in that, The device includes: a spool body; a guiding module disposed on the circumferential surface of the spool body, the guiding module including a plurality of guiding grooves parallel to and spaced apart from each other, for a cutting wire to wind thereon to form an array composed of a plurality of parallel cutting wire segments, and the array is used to cut a silicon rod into a plurality of silicon wafers at one time by moving along the extending direction of the cutting wire; wherein, the guiding module includes a tension adjusting section, and the tension adjusting section is configured to be able to drive the cutting wire segment wound on the tension adjusting section to move away from and towards the spool body together during the wire cutting operation, so as to adjust the actual tension of the cutting wire segment to a target tension; the tension adjusting section is in an arc shape, and one end of the tension adjusting section is connected to the spool body through a hinge, so that the tension adjusting section can rotate around the hinge away from and towards the spool body; 2. The device for wire-cutting silicon rods according to claim 1, wherein, the tension adjusting section includes a metal base and a resin part disposed on the upper surface of the metal base, wherein, the guiding groove is formed by the resin part; 3. The device for wire cutting silicon rods according to claim 2, characterized in that, the resin part is disposed on the metal base in a detachable manner; 4. The device for wire cutting silicon rods according to any one of claims 1 to 3, characterized in that, the device further includes: a detection module, and the detection module is used to detect the actual tension of the cutting wire segment; 5. The device for wire-cutting silicon rods according to claim 4, wherein, the device further includes: a control module communicating with the detection module, and the control module is used to control the offset of the tension adjusting section according to the detection result of the detection module; 6. The device for wire-cutting silicon rods according to claim 5, characterized in that, the device includes a processing module communicating with the detection module and the control module, and the processing module is used to obtain the offset amount of the tension adjusting section according to the detection result of the detection module and the target tension, and send the offset amount to the control module, and the control module controls the offset of the tension adjusting section based on the offset amount; 7. An apparatus for wire-cutting silicon rods, characterized in that, The equipment includes: the device for wire cutting a silicon rod according to any one of claims 1 to 6; a loading unit for loading and fixing the silicon rod to be processed; a movement control module for controlling the movement of the device for wire cutting a silicon rod and / or the loading unit, so that the device for wire cutting a silicon rod and the loading unit move towards each other to cut the silicon rod; 8. A method for manufacturing a silicon wafer, characterized in that, The method includes: manufacturing a silicon wafer by using the equipment for wire cutting a silicon rod according to claim 7, including the following steps: loading and fixing the silicon rod through the loading unit; controlling the device for wire cutting a silicon rod and the loading unit loaded with and fixed with the silicon rod to move towards each other to cut the silicon rod through the movement control unit; cleaning and detecting the silicon wafers obtained after cutting the silicon rod.

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