Tension adjusting method of wafer cutting line and slicing machine

Abstract

The invention provides a tension adjusting method of a wafer cutting line and a slicer, and the tension adjusting method of the wafer cutting line comprises the following steps: A, monitoring the thickness of a wafer and / or the tension of the cutting line, and determining an abnormal cutting line; b, according to delta Tadjust = K1 * delta H + K2 * (Ttarget-Tcurrent), the tension adjustment compensation amount delta Tadjust of the abnormal cutting line is obtained, K1 is the thickness deviation weight coefficient, K2 is the tension attenuation weight coefficient, delta H is the thickness deviation of the wafer cut by the last cutting, Ttarget is the target tension of the cutting, and Tcurrent is the tension when the abnormal cutting line is determined to be abnormal; and C, a wire passing wheel wound by the abnormal cutting wire serves as an adjusting target, and the adjusting target is driven until the adjusted tension Tadjust of the abnormal cutting wire meets the formula that Tadjust-Tcurrent = delta Tadjust.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor equipment production, and in particular to a tension adjustment method for a wafer cutting line and a slicer. Background Art

[0002] The multi-wire cutting process is a process that uses a slicer and diamond wire as the cutting device and cutting wire respectively to cut the crystal rod to obtain a wafer. At present, the multi-wire cutting process has problems such as uneven wafer thickness, increased TVV (total wafer thickness variation), and wafers with abnormal thickness appearing frequently, resulting in a decrease in wafer yield. The reasons for the deviation in wafer thickness include the attenuation of the tension of the cutting wire.

[0003] The existing technology provides a cutting line tension adjustment and compensation method based on manual intervention, which aims to increase the tension of the cutting line to offset the tension attenuation. The existing cutting line tension adjustment and compensation method relies on the experience and skills of the operator. The operator needs to judge the attenuation degree of the cutting line tension in real time. Improper operation can easily cause the cutting line tension to fluctuate, thus affecting the cutting stability. Manual operation is time-consuming and has hysteresis. Moreover, it cannot adapt to the cutting conditions where the attenuation degree of the cutting line tension changes dynamically in real time. For example, the cutting line tension attenuates to different degrees in different cutting times. Manual operation is usually a fixed value control, that is, manual operation is more suitable for adjusting and compensating for a specific degree of cutting line tension attenuation. Summary of the invention

[0004] In view of this, the present invention provides a tension adjustment method and a slicer for a wafer cutting line that can replace manual operation to adjust the tension of the cutting line to compensate for the tension attenuation of the cutting line, thereby adapting to the cutting conditions where the degree of tension attenuation of the cutting line changes dynamically in real time, thereby obtaining qualified wafers with uniform thickness, reducing TVV (total wafer thickness variation) and improving the yield rate of the wafer.

[0005] The tension adjustment method of the wafer cutting line of the present invention comprises: A. Monitor wafer thickness and / or cutting line tension and identify abnormal cutting lines; B. According to ΔT adjust =K1·ΔH+K2·(T target -T current ), and obtain the tension adjustment compensation value ΔT of the abnormal cutting line adjust , Among them, K1 is the thickness deviation weight coefficient, K2 is the tension attenuation weight coefficient, ΔH is the wafer thickness deviation of the previous cut, T target is the target tension for this cutting, T current The tension at which the abnormal cutting line is determined to be abnormal; C. Take the wire wheel around which the abnormal cutting line passes as the adjustment target, and drive the adjustment target until the adjusted tension T of the abnormal cutting line adjust Meet T adjust -T current =ΔT adjust .

[0006] The tension adjustment method of the wafer cutting line of the present invention comprehensively considers the wafer thickness deviation of the previous cutting and the cutting line tension deviation of the current cutting. Starting from the second cutting, the tension adjustment for the subsequent cutting is performed to compensate the tension ΔT. adjust All are based on the previous cutting according to ΔT adjust =K1·ΔH+K2·(T target -T current ) is determined so that the tension compensated for each cut and the actual tension at the beginning of each cut are dynamically adapted to each other. Therefore, the tension adjustment method for the wafer cutting line of the present invention can adapt to the cutting conditions where the attenuation degree of the cutting line tension changes dynamically in real time. There is no need to manually judge the attenuation degree of the cutting line tension in real time, and it no longer depends on the experience and skills of the operator. It can avoid the fluctuation of the cutting line tension caused by improper operation to ensure stable cutting.

[0007] In some embodiments, step C comprises C1. According to the relationship between the cutting line tension T and the position p of the wire wheel T(p) , determine the amount of activity that should be adjusted to adjust the target Δ p ; C2. Adjust the amount of activity according to Δ p Drive adjustment targets and complete tensioning.

[0008] In the first embodiment of the present invention, the relationship between the cutting line tension T and the wire wheel position p is: T(p) for: T= , p = θ; The amount of activity should be adjusted p =Δθ=(θ2-θ1), Among them, θ2 is the angular position of the adjustment target when tensioning is completed, θ1 is the angular position of the adjustment target when the abnormal cutting line is determined to be abnormal, τ is the output torque of the rotary motor, and L is the distance from the rotation center of the adjustment target to the revolution center of the adjustment target.

[0009] In some embodiments, the rotation center and the revolution center of the adjustment target are parallel to the axis of the winding roller. -10°≤θ≤10°, θ increases as the adjustment target moves away from the winding roller axis, and when the rotation center of the adjustment target is located vertically above the revolution center, θ=0°.

[0010] In the second embodiment of the present invention, the relationship between the cutting line tension T and the wire wheel position p is: T(p) for: T=K w ·( -L0), p = (S,0); The amount of activity should be adjusted p =Δ S = - , Among them, S is the horizontal position coordinate of the rotation center of the adjustment target, Δ S To adjust the translation of the target within the preset adjustment range, K w is the elastic coefficient of the cutting line, L0 is the initial length of the cutting line, and H is the offset distance from the top of the adjustment target.

[0011] In some embodiments, the rotation center of the adjustment target is parallel to the axis of the winding roller, and the translation direction of the adjustment target within the preset adjustment interval is perpendicular to the rotation center of the adjustment target; a≤S≤b, and S increases as the adjustment target moves away from the winding roller axis.

[0012] The slicer of the present invention is used to execute the method of embodiment 1, and includes a machine body, a winding roller shaft, a wire roller driving component, a wire passing wheel, an adjusting swing arm and a tensioning driving component. The winding roller shaft is rotatably disposed on the machine body, the wire roller driving component is drivingly connected to the winding roller shaft, the adjusting swing arm is hinged to the machine body, the tensioning driving component is drivingly connected to the adjusting swing arm, and the wire passing wheel is rotatably disposed on the adjusting swing arm.

[0013] In some embodiments, the axis of the winding roller, the axis of the wire wheel and the rotation center of the adjusting swing arm are parallel to each other, the axis of the wire wheel and the rotation center of the adjusting swing arm respectively form the rotation center and the revolution center of the wire wheel, and the tensioning drive member is used to drive the wire wheel to move away from the winding roller so as to increase the tension of the cutting line bypassing the wire wheel; and / or, The wire passing wheel comprises a middle wire passing wheel, and the winding roller shaft has a winding section extending in the axial direction, and two ends of the winding section are equidistant from the opposite sides of the middle wire passing wheel.

[0014] Another slicer of the present invention is used to execute the method of Example 2, including a machine body, a winding roller, a wire roller driving member, a wire passing wheel, a translation mechanism and a tensioning driving member. The winding roller is rotatably disposed on the machine body, the wire roller driving member is drivingly connected to the winding roller, the translation mechanism is slidably connected to the machine body, the tensioning driving member is drivingly connected to the translation mechanism, and the wire passing wheel is rotatably disposed on the translation mechanism.

[0015] In some embodiments, the axis of the winding roller is parallel to the axis of the wire passing wheel, and the translation mechanism and the body form a moving pair so that the translation mechanism translates in a direction perpendicular to the axis of the wire passing wheel. The tensioning drive is used to drive the wire wheel to move away from the winding roller shaft, so as to increase the tension of the cutting wire bypassing the wire wheel; and / or, The winding roller comprises a top winding roller, the side of the top winding roller facing away from the ground is higher than the side of the wire wheel facing away from the ground; and / or, The wire passing wheel comprises a middle wire passing wheel, and the winding roller shaft has a winding section extending in the axial direction, and two ends of the winding section are equidistant from the opposite sides of the middle wire passing wheel.

[0016] The slicer of the present invention can start from the second knife and cut according to ΔT based on the previous knife cutting. adjust =K1·ΔH+K2·(T target -T current ) Determine the tension ΔT required for the next cut adjust , so that the compensation tension obtained by each cut and the actual tension at the beginning of each cut can be dynamically adapted to each other. Therefore, the slicer of the present invention can adapt to the cutting conditions where the attenuation degree of the cutting line tension changes dynamically in real time. There is no need to manually judge the attenuation degree of the cutting line tension in real time, and it no longer depends on the experience and skills of the operator. It can avoid the fluctuation of the cutting line tension caused by improper operation to ensure stable cutting. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A partial structural schematic diagram of a slicer according to an embodiment of the present invention; Figure 2 It is a structural schematic diagram of a slicer for implementing the tension adjustment method of a wafer cutting line according to the first embodiment of the present invention; Figure 3 It is a schematic diagram of the operation of a slicer when tensioning a wafer cutting line for implementing the method for adjusting the tension of a wafer cutting line according to the first embodiment of the present invention; Figure 4 It is a schematic structural diagram of a slicer before adjusting the tension of a wafer cutting line for implementing the tension adjustment method of a wafer cutting line according to the second embodiment of the present invention; Figure 5 The schematic diagram is a structural diagram of a slicer for implementing the wafer cutting line tension adjustment method according to the second embodiment of the present invention when adjusting the cutting line tension.

[0018] Explanation of the reference numerals: 100, slicer; 10, machine body; 20, winding roller; 21, first winding roller; 22, second winding roller; 23, third winding roller; 30, wire wheel; 40, adjusting swing arm; 41, first rotation center; 42, revolution center; 50, translation mechanism; 51, second rotation center; 60, cutting line; 70, tensioning drive; 80, monitoring unit. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "or / and" used herein includes any and all combinations of one or more related listed items.

[0021] The present invention provides a method for adjusting the tension of a wafer cutting line and a slicer 100. The method for adjusting the tension of a wafer cutting line is used in a multi-line cutting process. The slicer 100 is used to perform the multi-line cutting process. The multi-line cutting process aims to use a cutting net formed by a cutting line 60 to cut a crystal rod to obtain a plurality of wafers arranged along the axial direction of the crystal rod, with uniform thickness and smooth cut surfaces. The wafers are used as raw materials for various semiconductor devices.

[0022] See also Figure 1~Figure 2 The slicer 100 of the present invention comprises a body 10, a wire roller drive and a plurality of winding roller shafts 20. The plurality of winding roller shafts 20 are arranged at intervals and their respective axes are parallel to each other. The cutting wire 60 adopts a diamond wire. The cutting wire 60 is wound on the outer peripheral surface of the plurality of winding roller shafts 20 to form a cutting net. The cutting net extends from the outer peripheral side of one winding roller shaft 20 to the outer peripheral side of another winding roller shaft 20. The wire roller drive is used to connect and drive at least one of the winding roller shafts 20 to rotate and drive the cutting wire 60. The axial direction of the crystal rod is perpendicular to the arrangement direction of the cutting wire 60 segments in the cutting net. When the crystal rod is translated from one side of the cutting net and passes through the plane where the cutting net is located until it reaches the other side of the cutting net, and at the same time, the wire roller drive drives the winding roller shaft 20 to rotate and drags the cutting net to move, the cutting net cuts the crystal rod into multiple wafers.

[0023] The existing multi-wire cutting process and slicer 100 are difficult to ensure a high yield rate of wafers. When cutting and processing crystal rods, there are problems such as uneven wafer thickness, increased TVV (total wafer thickness variation), and high frequency of abnormal thickness wafers. In particular, the thickness of the wafers in the middle position is obviously smaller, that is, after the same crystal rod is cut into multiple wafers, the thickness of the wafers shows a trend of first decreasing and then increasing from one end of the crystal rod to the other end. The larger the axial size of the crystal rod, the more serious the smaller thickness of the wafers in the middle position. The reason for the smaller wafer thickness mainly includes the attenuation of the tension of the cutting wire 60, that is, the tension of the cutting wire 60 used to cut the middle position of the crystal rod is less than the tension of the cutting wire 60 used to cut the two ends of the crystal rod.

[0024] In view of this, the present invention provides a method for adjusting the tension of a wafer cutting line, which is intended to adjust the tension of a cutting line 60 that has experienced tension attenuation so that the tension of the cutting line 60 can be compensated. By executing the method for adjusting the tension of a wafer cutting line, a multi-wire cutting process can cut out qualified wafers with uniform thickness, reduce TVV (total wafer thickness variation), and improve the yield rate of the wafer. The slicer 100 of the present invention also includes a monitoring unit 80 and a wire-passing wheel 30. The monitoring unit 80 includes a wafer thickness monitoring module and / or a cutting line 60 tension sensor. The wafer thickness monitoring module is used to monitor the thickness of the wafer, and the cutting line 60 tension sensor is used to monitor the tension of the cutting line 60. The wire-passing wheel 30 is movably arranged relative to the machine body 10, see Figure 1 The axis of the wire wheel 30 and the axis of the winding roller 20 are parallel to each other. The wire wheel 30 and the winding roller 20 are both used for the cutting wire 60 to pass around. The difference is that the axis of each winding roller 20 is fixed relative to the machine body 10, while the axis of the wire wheel 30 is movable relative to the machine body 10. The wire wheel 30 changes the tension of the cutting wire 60 by moving relative to the machine body 10, thereby changing the tension of the cutting net. After the tension of the cutting wire 60 is attenuated, in order to compensate the tension of the cutting wire 60 to offset the influence of the attenuation on the thickness of the wafer, the wire wheel 30 can be controlled to move in any direction away from the winding roller 20 to increase the tension of the cutting wire 60. Normally, the cutting line 60 where tension attenuation occurs can be determined based on past production and processing experience before the formal cutting process, that is, one or several cutting lines 60 used to cut out the wafer in the middle position, because the thickness of the wafer in the middle position is obviously smaller; in other cases, the cutting line 60 where tension attenuation occurs is not limited to the cutting line 60 that cuts out the wafer in the middle position, and tension attenuation may occur on each cutting line 60 on the cutting network.

[0025] The tension adjustment method of the wafer cutting line of the present invention comprises: A. monitoring wafer thickness and / or cutting line 60 tension, and identifying abnormal cutting lines 60; B. According to ΔT adjust=K1·ΔH+K2·(T target -T current ), and obtain the tension adjustment compensation amount ΔT of the abnormal cutting line 60 adjust , Among them, K1 is the thickness deviation weight coefficient, K2 is the tension attenuation weight coefficient, K1 and K2 are two dimensionless constants, the value range of K1 is 0.1~2.0, the size of K1 reflects the influence of the wafer thickness deviation of the previous cut on the cutting line 60 tension of this cut, the value range of K2 is 0.1~1.5, ΔH is the wafer thickness deviation of the previous cut, ΔH=H target -H previous , H target is the preset target thickness of the wafer to be cut this time, H previous is the thickness of the wafer cut by the last knife (calculated value), calculate H previous The methods include average method, weighted average method, regional segmentation method, etc. target is the target tension for this cutting, T current is the tension when the abnormal cutting line 60 is determined to be abnormal; C. Take the wire wheel 30 bypassed by the abnormal cutting line 60 as the adjustment target, and drive the adjustment target until the adjusted tension T of the abnormal cutting line 60 adjust Meet T adjust -T current =ΔT adjust .

[0026] Specifically, step C includes: C1. According to the relationship between the tension T of the cutting line 60 and the position p of the wire wheel 30 T(p) , determine the amount of activity that should be adjusted to adjust the target Δ p ; C2. Adjust the amount of activity according to Δ p Drive adjustment targets and complete tensioning.

[0027] Normally, the slicer 100 is initialized at the beginning of cutting the crystal rod, and the initialization setting includes setting the tension range of the cutting line 60 and calibrating the initial tension of the cutting net. Therefore, when the cutting line 60 cuts the first crystal rod for the first time after the initialization setting is completed, the tension of the cutting line 60 is calibrated without attenuation. Starting from the cutting of the second crystal rod, the tension of the cutting line 60 attenuates. Therefore, the tension adjustment method of the wafer cutting line of the present invention is suitable for the crystal rod cutting operation of the thickness cutting knife after the first cutting knife is completed. The first cutting knife is the first cutting of the first crystal rod by the cutting line 60.

[0028] Compared with the prior art, the tension adjustment method of the wafer cutting line of the present invention comprehensively considers the wafer thickness deviation of the previous cut and the cutting line 60 tension deviation of the current cut. In the multi-wire cutting process, the cutting line tension of each cut and the material removal condition of the cut crystal rod will affect the cutting effect of the next cut: if the wafer thickness deviation of the previous cut is large, the stress distribution of the cutting line will change significantly, thereby affecting the local stretching or relaxation of the cutting line during the next cut; the wafer thickness deviation of the previous cut may cause abnormal local temperature of the cutting line, and the temperature change affects the expansion degree of the cutting line, so that the tension of the cutting line during the next cut is affected by the expansion of the cutting line. In addition, the wafer thickness deviation of the previous cut will cause the cutting line to accumulate fatigue and fail to release fatigue stress in time, and will also cause the cutting line tension to be insufficient or too large during the next cut. If the cutting line tension error caused by the wafer thickness deviation of the previous cut cannot be compensated in time, the cutting line tension error will gradually accumulate. Therefore, starting from the second cut, the tension ΔT required to compensate for the tension adjustment of the next cut is adjust All are based on the previous cutting according to ΔT adjust =K1·ΔH+K2·(T target -T current ) to determine, for example: In the second cutting pass (i.e. the second cutting), the required compensation tension ΔT adjust Based on the first cut, ΔH is the wafer thickness deviation of the first cut, and the wafer thickness deviation ΔH is the target wafer thickness H of the first cut. target The actual thickness of the wafer at the first cut is H previous The difference, that is, ΔH = H target -H previous , T target is the tension that should be adjusted this time (i.e. the second cutting), T current is the current tension of the second knife cutting, that is, the tension of the cutting line 60 during the start of the second knife cutting; In the fourth cutting pass (i.e. the fourth cutting), the required compensation tension ΔT adjust Based on the third knife cutting, it is determined that ΔH is the wafer thickness deviation of the third knife cutting, and the wafer thickness deviation ΔH is the wafer target thickness H of the third knife cutting. target The actual thickness of the wafer at the third cut is H previous The difference, that is, ΔH = H target -H previous , T target is the tension that should be adjusted this time (i.e. the fourth cutting knife), T current is the current tension of the fourth knife cutting, that is, the tension of the cutting wire 60 during the beginning of the fourth knife cutting.

[0029] In this way, the tension compensated for each cut and the actual tension attenuation at the beginning of each cut are dynamically adapted. Therefore, the tension adjustment method of the wafer cutting line of the present invention can adapt to the cutting conditions where the degree of tension attenuation of the cutting line 60 changes dynamically in real time, which is more in line with the actual needs of crystal rod cutting processing. There is no need to manually judge the degree of attenuation of the cutting line 60 tension in real time, and it no longer depends on the experience and skills of the operator. It can avoid large fluctuations in the tension of the cutting line 60 caused by improper manual operation, and ensure the stable operation of the slicer 100. While considering the deviation of the cutting line tension of this cutting, the deviation of the wafer thickness of the previous cut is also considered to avoid the influence of the previous thickness deviation on the cutting line tension gradually accumulating and amplifying the influence in subsequent cuts. In each cut, the cutting line tension error from the wafer thickness deviation of the previous cut can be compensated and corrected, thereby ensuring that the cutting line tension is stable during each cut and each cutting line has a uniform tension distribution during each cut.

[0030] In contrast, the existing cutting line 60 tension adjustment and compensation means rely on the skills of the operator. Manual operation is based only on experience and can only compensate the cutting line 60 tension by a fixed value. The tension compensation amount after manual adjustment often cannot meet the cutting requirements of the current cutting knife. After compensating the tension, thin wafers may be cut. The large fluctuations in the cutting line 60 tension caused by manual operation will reduce the smoothness of the wafer cut surface. Quality evaluation indicators such as wafer line marks and TTV are difficult to meet. Only the wafer thickness indicator can be met. Each time a cut is made, the cutting line includes the tension error caused by the thickness deviation of the wafer of the previous cut.

[0031] Specifically, H is calculated by the average method. previous The formula is The calculation idea is to first measure the thickness values ​​of different positions of the wafer obtained by the previous cutting, and then calculate the arithmetic average of these thickness values; calculate H by weighted average method previous The formula is Compared with the average value method, the weighted average method gives a higher weight to the thickness of the key area of ​​the wafer (such as the middle of the wafer). The thickness values ​​of different positions of the wafer obtained by the previous cut can be measured by selecting points with a laser thickness gauge and collecting them in real time, or by scanning the wafer obtained by the previous cut.

[0032] It is worth mentioning that T target As the target tension for this cutting, only the compensation amount ΔT is adjusted with the tension of this cutting. adjust Related to the tension adjustment compensation ΔT of the previous cutting or the next cutting adjust For example, in the second cut, it is used to calculate the adjust -T current =ΔT adjustCalculate the target tension T used for the tension compensation required for the second knife cutting target It is only the target tension for the second cut and has nothing to do with the target tension for the first, third or fourth cut. In some cases, the target cutting tensions in different cutting passes are different.

[0033] Furthermore, T target The target tension for this cutting can be a fixed value or multiple different values. target When T is a fixed value, the cutting force of the cutting line 60 on the crystal rod is equal in each cutting stage of the cutting. target is a fixed value, which is suitable for the cutting conditions with stable cutting conditions and uniform crystal rod materials. target When T is a plurality of different values, the cutting force of the cutting wire 60 on the crystal rod may be different at each cutting stage of the cutting, which is equivalent to that a plurality of different values ​​together constitute the dynamic target tension of the cutting, that is, T target It is a dynamic value and changes as the cutting stage of this cutting progresses. Therefore, a fixed value T can be selected according to the actual cutting conditions and the uniformity of the crystal rod material. target or dynamic value T target As the target tension for this cutting.

[0034] H target As the target thickness of the wafer for this cutting, only the tension adjustment compensation amount ΔT for this cutting is used. adjust Related to the tension adjustment compensation ΔT of the previous cutting or the next cutting adjust For example, in the second cut, it is used to calculate the adjust =K1·(H target -H previous )+K2·(T target -T current ) Calculate the H used to compensate for the tension required for the second knife cutting target It is only the target thickness of the wafer for the second cut, and has nothing to do with the target thickness of the wafer for the first, third or fourth cut. In some cases, the target thickness of the wafer in different cut passes may be equal.

[0035] The relationship between the tension T of the cutting line 60 and the position p of the wire wheel 30 is: T(p) , Adjust the amount of activity to adjust the target Δ p It all depends on the installation method of the wire wheel 30 in the slicer 100 and the activity form of the wire wheel 30. Figure 2~Figure 3The slicer 100 shown also includes an adjustment swing arm 40 and a tensioning drive 70. One end of the adjustment swing arm 40 is hinged to the machine body 10, and the wire wheel 30 is rotatably mounted on the other end of the adjustment swing arm 40. The tensioning drive 70 drives and connects the adjustment swing arm 40 so as to drive the adjustment swing arm 40 to rotate relative to the machine body 10. The wire wheel 30 moves as the adjustment swing arm 40 rotates relative to the machine body 10, thereby realizing the movement of the wire wheel 30 relative to the winding roller 20. One end of the adjustment swing arm 40 on which the wire wheel 30 is mounted and the axis of the wire wheel 30 form a first rotation center 41 for the wire wheel 30 to rotate, and the other end of the adjustment swing arm 40 rotatably connected to the machine body 10 forms a revolution center 42 for the wire wheel 30 to revolve relative to the machine body 10. The wire wheel 30 rotates around the first rotation center 41 to adapt to the movement of the cutting line 60. When the wire wheel 30 rotates around the revolution center 42 and moves away from the winding roller 20 under the drive of the tensioning drive 70, the tension of the cutting line 60 increases, thereby achieving tensioning of the cutting line 60. When the tensioning drive 70 drives the adjusting swing arm 40 to rotate around the revolution center 42 to tension the cutting line 60, the axis of the wire wheel 30 passing through the first rotation center 41 rotates around the revolution center 42 to form an arc track. Optionally, Figure 2~Figure 3 In the slicer 100 shown in the figure, the axis of the winding roller 20, the axis of the wire passing wheel 30 and the rotation center of the adjusting swing arm 40 are parallel to each other. Figure 1 The YOZ plane shown rotates around the revolution center 42, Figure 3 In the slicer 100 shown, the tensioning drive 70 drives the adjusting swing arm 40 to rotate around the revolution center 42 in an angle range of 20°; in other embodiments, the tensioning drive 70 drives the adjusting swing arm 40 to rotate around the revolution center 42 in an angle range not limited to 20°.

[0036] Furthermore, the outer peripheral wall of the winding roller 20 has a winding section for the cutting wire 60 to pass through, and the winding section extends along the axial direction of the winding roller 20. The wire passing wheel 30 includes at least a middle wire passing wheel 30, and the opposite sides of the middle wire passing wheel 30 are equidistant from the two ends of the winding section. The middle wire passing wheel 30 is specifically used to tension and adjust the tension compensation for the cutting wire 60 in the middle position of the cutting net, so as to be specifically used to overcome the problem of abnormally small thickness of the wafer in the middle position. When the tensioning drive 70 drives the middle wire passing wheel 30 to rotate around the revolution center 42 and away from the winding roller 20, the cutting wire 60 bypassing the middle wire passing wheel 30 is tension compensated and thus tensioned, and the tension of the cutting wire 60 is adjusted to be close to the tension of the cutting wire 60 at the two sides of the cutting net. The wafers cut out by the cutting wire 60 finally meet the thickness requirements, and the multiple wafers cut out of the same crystal rod by the cutting net have a relatively uniform thickness size. It can be understood that on the basis of the middle wire-passing wheel 30, the number of wire-passing wheels 30 can be further increased, and multiple wire-passing wheels 30 are arranged in sequence along the axial direction of the winding roller 20. The uniformity of the tension of the cutting wire 60 in the cutting net is improved with the increase in the number of wire-passing wheels 30. The thickness of multiple chips cut out of the same crystal rod by the cutting net is more uniform and consistent, and the chip yield rate is higher.

[0037] Figure 4~Figure 5 The slicer 100 shown also includes a translation mechanism 50 and a tensioning drive 70. The translation mechanism 50 is slidably connected to the machine body 10, and the wire wheel 30 is rotatably mounted on the translation mechanism 50. The tensioning drive 70 drives the translation mechanism 50 so as to drive the translation mechanism 50 to translate relative to the machine body 10. The wire wheel 30 moves as the translation mechanism 50 translates relative to the machine body 10, thereby realizing the movement of the wire wheel 30 relative to the winding roller 20. The position where the wire wheel 30 is installed on the translation mechanism 50 and the axis of the wire wheel 30 form a second rotation center 51 for the wire wheel 30 to rotate. The wire wheel 30 rotates around the second rotation center 51 to adapt to the movement of the cutting line 60. When the wire wheel 30 translates with the translation mechanism 50 and moves away from the winding roller 20 under the drive of the tensioning drive 70, the tension of the cutting line 60 increases, thereby realizing the tensioning of the cutting line 60. When the tensioning drive 70 drives the translation mechanism 50 to move relative to the machine body 10 to tension the cutting line 60, the axis of the wire wheel 30 passing through the second rotation center 51 translates to form a straight line track. Optionally, the axis of the winding roller 20 is parallel to the axis of the wire wheel 30, and the translation mechanism 50 and the machine body 10 form a moving pair so that the translation mechanism 50 translates in a direction perpendicular to the axis of the wire wheel 30. The wire wheel 30 is in the direction of the rotation center 51. Figure 1 The YOZ plane is shown as translational in a direction parallel to the Y axis.

[0038] Furthermore, the outer peripheral wall of the winding roller 20 has a winding section, and the winding section extends along the axial direction of the winding roller 20. The wire-passing wheel 30 includes at least a middle wire-passing wheel 30, and the opposite sides of the middle wire-passing wheel 30 are equidistant from the two ends of the winding section. The middle wire-passing wheel 30 is specifically used to tension and adjust the tension compensation for the cutting wire 60 in the middle position of the cutting net, so as to be specifically used to overcome the problem of abnormally small thickness of the wafers in the middle position. When the tensioning drive 70 drives the middle wire-passing wheel 30 to translate relative to the machine body 10 and away from the winding roller 20, the cutting wire 60 bypassing the middle wire-passing wheel 30 is tension-compensated and thus tensioned, and the tension of the cutting wire 60 is adjusted to be close to the tension of the cutting wire 60 at the two sides of the cutting net. The wafers cut out by the cutting wire 60 finally meet the thickness requirements, and the multiple wafers cut out of the same crystal rod by the cutting net have a relatively uniform thickness size. It can be understood that on this basis, the number of wire-passing wheels 30 can be further increased. For example, two or more wire-passing wheels 30 can be set, and the multiple wire-passing wheels 30 are arranged in sequence along the axial direction of the winding roller 20. The uniformity of the tension of the cutting wire 60 in the cutting net increases with the increase in the number of wire-passing wheels 30. The thickness dimensions of multiple wafers cut out of the same crystal rod by the cutting net at one time become more uniform, and the wafer yield rate is higher.

[0039] Based on the above two slicers 100, the present invention provides two embodiments of a method for adjusting the tension of a wafer cutting line. The two embodiments respectively provide two relationship equations between the tension T of the cutting line 60 and the position p of the wire wheel 30. T(p) , and propose the two adjustment targets for the amount of activity to be adjusted Δ p The tension adjustment method of the wafer cutting line of the first embodiment is applicable to the following Figure 2~Figure 3 The slicer 100 shown in the figure is suitable for a slicer 100 in which the wire wheel 30 is installed on the adjusting swing arm 40, the adjusting swing arm 40 is hinged to the body 10, and the tension driving member 70 is drivingly connected to the adjusting swing arm 40 and is used to drive the adjusting swing arm 40 to rotate. The tension driving member 70 in the slicer 100 can be a rotary motor, and the rotary motor outputs a constant torque τ to the adjusting swing arm 40. The tension adjustment method of the wafer cutting line of the second embodiment is suitable for the following example. Figure 4~Figure 5 The slicer 100 shown is suitable for a slicer 100 in which the wire wheel 30 is installed on the translation mechanism 50, the translation mechanism 50 is slidably connected to the body 10, and the tensioning drive member 70 is drivingly connected to the translation mechanism 50 and is used to drive the translation mechanism 50 to translate. The tensioning drive member 70 in the slicer 100 can adopt a push rod motor, and the push rod motor drives the translation mechanism 50 to move in a uniform linear motion.

[0040] Specifically, in the first embodiment, the relationship between the tension T of the cutting line 60 and the position p of the wire wheel 30 is: T(p) for: T= , p = θ; The amount of activity should be adjusted p =Δθ=(θ2-θ1), Among them, θ is the swing angle of the adjusting swing arm 40, which also represents the angular position of the adjusting target, θ2 is the angular position when the adjusting target completes tensioning, which is also equal to the angle of the adjusting swing arm 40 when the adjusting target completes tensioning, θ1 is the angular position when the adjusting target is determined to be abnormal on the abnormal cutting line 60, which is also equal to the angle of the adjusting swing arm 40 when the adjusting target is determined to be abnormal on the abnormal cutting line 60, τ is the output torque of the rotating motor, L is the distance from the rotation center of the adjusting target to the revolution center 42 of the adjusting target, the rotation center of the adjusting target is the axis of the adjusting target, and is also the first rotation center 41 of the adjusting swing arm 40 where the adjusting target is located.

[0041] In some embodiments, the swing arm 40 is adjusted to rotate around the revolution center 42 in an angle range of 20°. Figure 3 As shown, -10°≤θ≤10°, θ increases as the adjustment target moves away from the winding roller 20, Figure 3 In the embodiment, the wire wheel 30 located on the left side of the winding roller 20 rotates clockwise around the revolution center 42 and approaches the winding roller 20, thereby slackening the cutting wire 60; and rotates counterclockwise and moves away from the winding roller 20, thereby increasing the tension of the cutting wire 60; the wire wheel 30 located on the right side of the winding roller 20 rotates counterclockwise around the revolution center 42 and approaches the winding roller 20, thereby slackening the cutting wire 60; and rotates clockwise and moves away from the winding roller 20, thereby increasing the tension of the cutting wire 60. When the first rotation center 41 of the adjustment target is located vertically above the revolution center 42, θ=0°, Figure 3 The wire wheel 30 presented with a solid line outline corresponds exactly to the situation of θ=0°, the first rotation center 41 of the adjustment target and the revolution center 42 of the adjustment target are located in the same vertical plane, and the dotted line outline represents the extreme position of the rotation of the wire wheel 30 around the revolution center 42.

[0042] In the second embodiment, the relationship between the tension T of the cutting line 60 and the position p of the wire wheel 30 is: T(p) for: T=K w ·( -L0), p = (S,0); The amount of activity should be adjusted p =Δ S = - , The rotation center of the adjustment target is the second rotation center 51 of the wire passing wheel 30, and the rotation center of the adjustment target is parallel to the axis of the winding roller 20. The wire passing wheel 30 is driven by the tensioning drive 70 to translate in a straight line in the horizontal direction in a plane perpendicular to the axial direction of the winding roller 20. Figure 4~Figure 5 In the plane rectangular coordinate system ZOY shown, the Z axis direction is the vertical direction, the Y axis direction is the horizontal direction, the YOZ plane is perpendicular to the axis of the winding roller 20 and the axis of the wire wheel 30, (S, 0) is an ordered number pair located on the Y axis in the ZOY coordinate system, and the number pair represents the position of the axis of the wire wheel 30, S is the horizontal coordinate of the second rotation center 51 of the adjustment target, and the translation direction of the adjustment target within the preset adjustment interval is always perpendicular to the second rotation center 51 of the adjustment target and is always parallel to the Y axis direction, Δ S To adjust the translation of the target within the preset adjustment range, Δ S This corresponds to the amount of movement of the tensioning drive member 70 driving the wire wheel 30 to translate in the horizontal direction from the start of tensioning the cutting wire 60 to the completion of tensioning the cutting wire 60. Figure 4~Figure 5 As shown, the preset adjustment interval is a horizontal interval, the horizontal coordinates of the starting point and the end point of the horizontal interval are a and b respectively, (a, 0) and (b, 0) respectively represent the projection points of the starting point and the end point of the preset adjustment interval on the Y axis, the relationship between a, b and S always satisfies a≤S≤b, the second rotation center 51 of the wire wheel 30 always moves within the preset adjustment interval, K w is the known elastic coefficient of the cutting wire 60 , L0 is the initial length of the cutting wire 60 , H is the offset from the top of the adjustment target, and H remains unchanged when the wire wheel 30 is driven to translate by the tensioning driving member 70 .

[0043] See also Figure 4~Figure 5 The initial length L0 of the line refers to: the length of the straight section of the cutting line 60 passing through the initial position wire wheel 30 and the top winding roller 20 closest to the initial position wire wheel 30. Since the cutting line 60 has initial tension, the portion of the cutting line 60 passing through the initial position wire wheel 30 and the top winding roller 20 closest to the initial position wire wheel 30 is a straight line and is tangent to the initial position wire wheel 30 and the top winding roller 20 closest to the initial position wire wheel 30.

[0044] Figure 4~Figure 5 In the slicer shown, there are three winding rollers 20, which are arranged axially in parallel. When the slicer 100 is observed along the axial direction of the winding rollers 20, the axis connecting the three winding rollers 20 is in a triangle shape. The three winding rollers 20 in the figure are the first winding roller 21, the second winding roller 22 and the third winding roller 23, respectively. The distance from the first winding roller 21 to the ground is smaller than the distance from the second winding roller 22 to the ground, and the distance from the first winding roller 21 to the ground is smaller than the distance from the third winding roller 23 to the ground. Figure 4~Figure 5The third winding roller 23 located on the upper right is the top winding roller 20 closest to the initial position wire wheel 30; the initial position wire wheel 30 is the wire wheel 30 when the horizontal coordinate of the second rotation center 51 is equal to a and is located at the starting point of the preset adjustment range.

[0045] See also Figure 4~Figure 5 , the two winding rollers 20 farther from the ground are both used as the top winding rollers 20, and the sides of the two top winding rollers 20 facing away from the ground are at the same height and are both higher than the side of the wire wheel 30 facing away from the ground. The adjustment target's top offset H refers to: the distance between the horizontal plane where the wire wheel 30 axis is located and the highest tangent plane of the top winding roller 20 closest to the initial position wire wheel 30, the highest tangent plane is a horizontal plane and is tangent to the side of the top winding roller 20 facing away from the ground. The wire wheel 30 moves horizontally within the preset adjustment range, and the axis of the winding roller 20 is fixed, so the adjustment target's top offset H remains unchanged. Figure 4~Figure 5 In the ZOY rectangular coordinate system shown, the adjustment target's top offset H = (the vertical coordinate of the axis of the top winding roller 20 closest to the initial position passing wheel 30) + (the radius of the top winding roller 20 closest to the initial position passing wheel 30) - (the vertical coordinate of the second rotation center 51).

[0046] In other embodiments, the number of winding rollers 20 can also be two. When the two winding rollers 20 are arranged horizontally at intervals, the adjustment target's top offset H is the distance between the horizontal plane where the axis of the wire wheel 30 is located and the highest tangent plane of the winding roller 20 closest to the wire wheel 30 at the initial position.

[0047] Specifically, in Figure 4~Figure 5 In the plane rectangular coordinate system ZOY shown, the Z axis passes through and is perpendicular to the axis of the top winding roller 20 closest to the initial position of the wire wheel 30, and the Y axis passes through the axis of the wire wheel 30, that is, the Y axis is perpendicular to the second rotation center 51. Therefore, when the axis of the wire wheel 30 moves to the starting point of the preset adjustment interval, the coordinates of the second rotation center 51 are (a, 0); when the axis of the wire wheel 30 moves to the end point of the preset adjustment interval, the coordinates of the second rotation center 51 are (b, 0), and the moving trajectory of the second rotation center 51 is the line connecting (a, 0) and (b, 0). The second rotation center 51 translates along the Y axis and keeps the vertical coordinate equal to 0. Therefore, in Figure 4~Figure 5 In the plane rectangular coordinate system ZOY shown, the adjustment target's top offset H = (the ordinate of the axis of the top winding roller 20 closest to the initial position wire wheel 30) + (the radius of the top winding roller 20 closest to the initial position wire wheel 30), Δp = ΔS =S-a, S is numerically equal to the horizontal coordinate of the second rotation center 51 in the rectangular coordinate system ZOY.

[0048] S increases as the tension driving member 70 drives the adjustment target away from the winding roller 20 , and decreases as the tension driving member 70 drives the adjustment target closer to the winding roller 20 . Figure 4~Figure 5 In the slicer 100 shown, the wire passing wheel 30 located on the right side of the winding roller 20 moves away from the winding roller 20 in the positive direction along the Y axis, thereby increasing the tension of the cutting wire 60; and the wire passing wheel 30 moves closer to the winding roller 20 in the negative direction along the Y axis, thereby relaxing the cutting wire 60. Figure 5 The wire wheel 30 shown in the solid outline satisfies S= The dotted outline located on the left side of the solid line outline and the dotted outline located on the right side of the solid line outline respectively represent the position of the wire passing wheel 30 when S=a and S=b, that is, the two dotted line outlines respectively represent the situation where the wire passing wheel 30 follows the translation mechanism 50 to translate to the extreme position.

[0049] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0050] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present invention, and are not intended to limit the present invention. As long as they are within the spirit of the present invention, appropriate changes and modifications to the above embodiments are within the scope of protection claimed by the present invention.

Claims

1. A method for adjusting the tension of a wafer cutting line, characterized in that: include A. monitoring wafer thickness and / or cutting line (60) tension, and identifying abnormal cutting lines; B. According to ΔT adjust =K1·ΔH+K2·(T target -T current ), and obtain the tension adjustment compensation value ΔT of the abnormal cutting line adjust , Among them, K1 is the thickness deviation weight coefficient, K2 is the tension attenuation weight coefficient, ΔH is the wafer thickness deviation of the previous cut, T target is the target tension for this cutting, T current The tension at which the abnormal cutting line is determined to be abnormal; C. Take the wire wheel (30) around which the abnormal cutting line passes as the adjustment target, and drive the adjustment target until the adjusted tension T of the abnormal cutting line is adjust Meet T adjust -T current =ΔT adjust .

2. The method for adjusting the tension of a wafer cutting line according to claim 1, wherein: Step C includes C1. According to the relationship between the tension T of the cutting line (60) and the position p of the wire wheel (30): T(p) , determine the amount of activity that should be adjusted to adjust the target Δ p ; C2. Adjust the amount of activity according to Δ p Drive adjustment targets and complete tensioning.

3. The method for adjusting the tension of a wafer cutting line according to claim 2, wherein: The relationship between the tension T of the cutting line (60) and the position p of the wire wheel (30) is: T(p) for: T= ,p=θ; The amount of activity should be adjusted p =Δθ=(θ2-θ1), Among them, θ2 is the angular position of the adjustment target when tensioning is completed, θ1 is the angular position of the adjustment target when the abnormal cutting line is determined to be abnormal, τ is the output torque of the rotary motor, and L is the distance from the rotation center of the adjustment target to the revolution center of the adjustment target.

4. The method for adjusting the tension of a wafer cutting line according to claim 3, wherein: The rotation center and revolution center of the adjustment target are parallel to the axis of the winding roller (20), -10°≤θ≤10°, θ increases as the adjustment target moves away from the winding roller axis (20), and when the rotation center of the adjustment target is located vertically above the revolution center, θ=0°.

5. The method for adjusting the tension of a wafer cutting line according to claim 2, wherein: The relationship between the tension T of the cutting line (60) and the position p of the wire wheel (30) is: T(p) for: T=K w ·( -L0),p=(S,0); The amount of activity should be adjusted p =Δ S = - , Among them, S is the horizontal position coordinate of the rotation center of the adjustment target, Δ S To adjust the translation of the target within the preset adjustment range, K w is the elastic coefficient of the cutting line (60), L0 is the initial length of the cutting line (60), and H is the offset distance from the top of the adjustment target.

6. The method for adjusting the tension of a wafer cutting line according to claim 5, wherein: The rotation center of the adjustment target is parallel to the axis of the winding roller (20), and the translation direction of the adjustment target within the preset adjustment range is perpendicular to the rotation center of the adjustment target; a≤S≤b, and S increases as the adjustment target moves away from the winding roller axis (20).

7. A slicer for executing the method according to claim 3 or claim 4, characterized in that: The invention comprises a machine body (10), a winding roller shaft (20), a wire passing wheel (30), an adjusting swing arm (40) and a tensioning driving member (70), wherein the winding roller shaft (20) is rotatably arranged on the machine body (10), the adjusting swing arm (40) is hinged to the machine body (10), the tensioning driving member (70) is drivingly connected to the adjusting swing arm (40), and the wire passing wheel (30) is rotatably arranged on the adjusting swing arm (40).

8. The slicer according to claim 7, characterized in that: The axis of the winding roller (20), the axis of the wire passing wheel (30) and the rotation center of the adjusting swing arm (40) are parallel to each other. The axis of the wire-passing wheel (30) and the rotation center of the adjusting swing arm (40) respectively form the rotation center and revolution center of the wire-passing wheel (30). The tension driving member (70) is used to drive the wire passing wheel (30) to move away from the winding roller (20) so as to increase the tension of the cutting wire (60) bypassing the wire passing wheel (30); and / or, The wire passing wheel (30) comprises a middle wire passing wheel, and the winding roller (20) has a winding section extending in the axial direction, with two ends of the winding section being equidistant from two opposite sides of the middle wire passing wheel.

9. A slicer for executing the method according to claim 5 or claim 6, characterized in that: The invention comprises a machine body (10), a winding roller (20), a wire passing wheel (30), a translation mechanism (50) and a tensioning drive component (70), wherein the winding roller (20) is rotatably arranged on the machine body (10), the translation mechanism (50) is slidably connected to the machine body (10), the tensioning drive component (70) is drivingly connected to the translation mechanism (50), and the wire passing wheel (30) is rotatably arranged on the translation mechanism (50).

10. The slicer according to claim 9, characterized in that The axis of the winding roller (20) and the axis of the wire passing wheel (30) are parallel to each other, and the translation mechanism (50) and the machine body (10) form a moving pair so that the translation mechanism (50) can translate in a direction perpendicular to the axis of the wire passing wheel (30). The tension driving member (70) is used to drive the wire passing wheel (30) to move away from the winding roller (20) so as to increase the tension of the cutting wire (60) bypassing the wire passing wheel (30); and / or, The winding roller (20) comprises a top winding roller, the side of the top winding roller facing away from the ground is higher than the side of the wire passing wheel (30) facing away from the ground; and / or, The wire passing wheel (30) comprises a middle wire passing wheel, and the winding roller (20) has a winding section extending in the axial direction, with two ends of the winding section being equidistant from two opposite sides of the middle wire passing wheel.

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