JP2007276048A - Workpiece cutting method using wire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize the quality of a cut thin plate (wafer) and to reduce the manufacturing cost regardless of the length of a workpiece such as an ingot as a cut object. <P>SOLUTION: The ingot 1 is cut so that the abrasion loss of the wire 6 after cutting is constant regardless of the length of the ingot 1, or so that the variation ▵W of thickness of the wafer 1a is constant (▵W2) regardless of the length of the ingot 1, and so that the quantity of a new wire supplied is set so that more the length L3 of the ingot 1 to be cut is gradually decreased to L3, L2, L1, the more the quantity of new wire supplied is decreased. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method of cutting a workpiece such as a semiconductor ingot, a magnetic material, or a ceramic into a thin plate with a wire such as a piano wire or a steel wire, and more particularly, a method of cutting a single crystal silicon ingot into a silicon wafer using a saw wire device. It is about.

  In the silicon wafer cutting process, the single crystal silicon ingot is cut by a wire saw device. That is, a slurry containing abrasive grains is supplied to the cutting portion of the single crystal silicon ingot, and while the tensile load is applied to the wire that is wound around the roller, the silicon ingot is relatively moved in the direction of pressing the wire against the wire. Then, a plurality of silicon wafers are acquired. In the longitudinal direction of the roller, a wire is wound at a predetermined pitch, and as shown in FIG. 1 (b), a wafer having a thickness corresponding to the roller pitch length, where the ingot is pressed The number of silicon wafers 1 a corresponding to the number of wire turns is simultaneously generated from one silicon ingot 1.

  In the cutting process, in order to improve the yield of silicon wafer production by improving the acquisition rate of silicon wafers, it is required to reduce “g / piece” to minimize the production loss. Here, “g / sheet” is a value obtained by dividing the weight of the silicon ingot by the number of silicon wafers acquired from the silicon ingot.

  It has been found that the kerf loss (cutting allowance) can be reduced in order to reduce “g / sheet”.

  FIG. 1A conceptually shows a state where the ingot 1 is cut into the wafer 1 a by the wire 6. Since the abrasive grains 31 in the slurry are interposed between the wire 6 and the cut surface, the kerf loss (cutting allowance) adds the wire diameter of the wire 6 to twice the grain diameter of the abrasive grains. Length. Further, as shown in FIG. 1B, since it is necessary to secure a machining allowance for performing processing such as etching in the subsequent process of the cutting process, the manufacturing loss increases as the machining allowance increases.

  Further, it is ideal that the wafer 1a produced by cutting has a completely flat cut surface, and the flatness (TTV value) and surface roughness (Ra value) are as small as possible. desirable.

  If the flatness (TTV value) and surface roughness (Ra value) of the cut surface of the wafer 1a (the surface of the wafer 1a) show large values, it will take time and labor for the lapping process, etching process, polishing process, etc. In short, the manufacturing efficiency of the wafer is impaired.

  Further, as shown in FIG. 2, periodic irregularities called “waviness” may occur on the cut surface of the wafer 1a.

  Further, as shown in FIG. 3, the wafer 1a may have a warp called warp as shown in FIG.

  When “undulation” or warp occurs, time and labor are required for the subsequent lapping process, etching process, polishing process, etc., and the wafer production efficiency is impaired.

  In addition, the warp direction and thickness may vary between individual wafers 1a obtained from silicon ingots. If these variations occur, time and labor are required for the lapping process, etching process, polishing process, etc. in the subsequent processes. However, the manufacturing efficiency of the wafer is impaired.

  One of the causes of quality deterioration of the surface of the wafer 1a is the wear of the wire 6.

  In Non-Patent Document 1 below, from the lower left column (1) and (1) on page 184, from the lower column to the third column on the right column, “As the wire wear increases (the wire radius decreases). The amplitude of the waviness of the cut surface of the wafer is increased. In addition, this document 1 states that “in order to suppress wire wear, it is effective to increase the feeding speed of a new wire. However, increasing the feeding speed increases the running cost. It is necessary to find a point. "

  Of the longitudinal sections of the roller around which the wire 6 is wound, a side where the new wire 6 is supplied (new line side), a side where the wire 6 used for cutting is wound (winding side), If the pitch between the wires 6 wound around the roller is the same at each part of the roller, the wire 6 wound around the roller part on the new wire side is wound around the roller part on the winding side. Since the worn wire 6 is more worn, the thickness of the wafer 1a obtained on the winding side becomes thicker than the thickness of the wafer 1a obtained on the new line side. That is, as can be seen from FIGS. 1A and 1B, the wear of the wire 6 proceeds and the kerf loss decreases as the wire diameter decreases and the thickness of the wafer 1a increases.

  For this reason, variations in thickness occur between the wafers acquired from the ingot 1.

Therefore, conventionally, a technique of reducing the pitch between the wires wound around the roller from the new line side toward the winding side is applied to the wire saw device.
Journal of Precision Engineering vol. 60, No. 2, 1994 (especially (1) in the lower left orchid on page 184 and right column, line 3 from the bottom of equation (1))

  There are various lengths of ingots to be cut by the wire saw device. Further, not only one ingot but also two ingots may be arranged in a line along the longitudinal direction of the roller (two pasted) and cut.

  However, in the conventional wire saw device, the speed at which a new wire is supplied to the roller, that is, the new wire supply amount (m / min) is constant regardless of the length of the ingot, resulting in the following problems. It was.

  That is, when the ingot 1 to be cut is long, as described above, the thickness variation between the wafers 1a becomes remarkable, and the warp varies among the wafers 1a, resulting in unstable quality. To do. On the other hand, when the ingot 1 to be cut is short, the above-described variation in quality is small and the quality is relatively stable, but the new wire 6 is consumed more than necessary, resulting in an increase in manufacturing cost. .

  Note that the contents described in Non-Patent Document 1 and the technique of changing the pitch length of the rollers do not consider the length of the ingot.

  The present invention has been made in view of such a situation, and solves the problem of stabilizing the quality of a cut thin plate (wafer) and reducing the manufacturing cost regardless of the length of a workpiece such as an ingot to be cut. It is to be an issue.

The first invention is
In a workpiece cutting method in which a new wire is supplied at a predetermined new wire supply amount, and the workpiece is moved relative to a wire that is wound around a roller in the direction of pressing to cut the workpiece into a thin plate. ,
New line supply amount so that the amount of new wire supply decreases as the length of the workpiece to be cut decreases so that the amount of wire wear after cutting is constant regardless of the length of the workpiece. Is set, and the workpiece is cut using a wire.

The second invention is
In a workpiece cutting method in which a new wire is supplied at a predetermined new wire supply amount, and the workpiece is moved relative to a wire that is wound around a roller in the direction of pressing to cut the workpiece into a thin plate. ,
Set the new line supply amount so that the variation in the thickness of the thin plate is constant regardless of the length of the workpiece, and the new line supply amount decreases as the length of the workpiece to be cut decreases. Thus, it is a method for cutting a workpiece with a wire so as to cut the workpiece.

The third invention is the first invention or the second invention,
The workpiece is a semiconductor ingot, and the thin plate is a semiconductor wafer.

  According to the present invention, as shown in FIG. 7B, the amount of wear of the wire 6 after the cutting process is constant regardless of the length of the ingot 1, or the thickness variation ΔW of the wafer 1a. As the length of the ingot 1 to be cut becomes smaller in order of L3, L2, and L1 so that it becomes constant (ΔW2) regardless of the length of the ingot 1, the new line supply amount decreases. A new line supply amount is set and the ingot 1 is cut.

  As a result, as shown by straight lines C3, C2, and C1 in FIG. 7B, the inclination of the straight lines increases as the total length of the ingot 1 decreases (L3 → L2 → L1). Regardless of the total length, the wear amount of the wire 6 is stabilized, and the variation in thickness between the wafers 1a obtained from the ingots of each length is stabilized at a value of ΔW2.

  For this reason, according to the present invention, the length of the ingot 1 is not affected, the quality standard level of the thickness variation is satisfied, and the quality related to the thickness variation is stabilized regardless of the length of the ingot 1. In addition, the quality related to warp and swell is stabilized. Moreover, about the ingot 1 of short length L1, since cutting is performed with the supply amount smaller than the conventional new line supply amount, a manufacturing cost is reduced.

  The present invention can be applied to a case where a semiconductor ingot such as a silicon ingot is cut into a semiconductor wafer such as a silicon wafer (third invention), but a work other than the semiconductor ingot, that is, a work made of magnetic material, ceramic, glass or the like. Can also be applied to the case of cutting a thin plate with a wire.

  Embodiments of a method for cutting a workpiece with a wire according to the present invention will be described below with reference to the drawings. In the present embodiment, a semiconductor ingot such as a silicon ingot is assumed as a workpiece, and a case where the workpiece is cut into a semiconductor wafer such as a silicon wafer by a wire is assumed. However, in the present invention, a workpiece other than the semiconductor ingot, that is, magnetic When a workpiece such as a material, ceramic, or glass is cut into a thin plate with a wire, it can be similarly applied.

  In the following description, it is assumed that a silicon wafer 1a having a diameter of 200 mm is manufactured. However, the present embodiment can be similarly applied when manufacturing a wafer having an arbitrary diameter such as a silicon wafer having a diameter of 300 mm.

  FIG. 4 is a perspective view showing the configuration of the wire saw device of the embodiment. FIG. 5 is a view showing a state in which the silicon ingot 1 is cut by the wire 6, and is a view of the silicon ingot 1 as viewed from the cut surface direction.

  As shown in these drawings, the rollers 7, 8, 9 are arranged at a predetermined distance so that the longitudinal axis directions of the processing rollers 7, 8, 9 coincide with the longitudinal axis direction of the silicon ingot 1. The processing rollers 7 and 8 are disposed on the upper side in the figure, and the processing roller 9 is disposed on the lower side in the figure. A wire 6 is wound around each of the rollers 7, 8, 9. The wire 6 is fed to the rollers 7, 8, and 9 by the feeding reel 10 and wound by a winding reel (not shown). The feeding reel 10 is driven by a reel driving motor 11.

  A wire 6 is wound around each of the rollers 7, 8 and 9 at a constant pitch along the longitudinal direction of the roller. The distance between the roller pitches is set to a length corresponding to the thickness of the wafer 1a (FIG. 1B).

  Further, a constant tension, that is, a constant tensile load (tension; kg / f) is applied to the wire 6 between the rollers 7, 8, 9 by the tension adjusting mechanism. That is, a tension adjusting guide roller 12 is provided between the feed-side reel 10 and the rollers 7, 8, 9, and the wire 6 is wound around the tension adjusting guide roller 12. The position of the tension adjusting guide roller 12 is adjustable, and the tensile load of the wire 6 is adjusted by adjusting the position of the tension adjusting guide roller 12. For example, the actual tensile load of the wire 6 is detected by a sensor, and the position of the tension adjusting guide roller 12 is adjusted so that a desired constant tensile load can be obtained using the detection result of the sensor as a feedback amount. .

  A rotating shaft of a roller driving motor 13 is connected to any one of the processing rollers 7, 8, 9. When the roller driving motor 13 is rotationally driven, for example, the seven processing rollers are rotationally driven, and accordingly, the other rollers 8 and 9 are driven to rotate and the wire 6 travels.

  In FIG. 5, the rollers 7, 8, and 9 rotate in the left direction, so that the wire 6 travels counterclockwise. As the wire 6 travels in one direction (left direction), the wire 6 is taken up by the take-up reel. When the wire 6 is fed leftward at a predetermined amount and at a predetermined constant speed, the traveling speed is reduced and temporarily stopped, and the roller driving motor 13 is rotationally driven in the reverse direction (rightward). The take-up reel functions as a feed reel, and the wire 6 runs in the reverse direction (right direction). When the traveling speed of the wire 6 increases and reaches a constant speed, the wire 6 travels while maintaining a predetermined amount and a predetermined constant speed in the same manner as when traveling in the left direction. Thereafter, the same cycle is repeated. Such reciprocation of the wire 6 is taken as one cycle, and the silicon ingot 1 is cut. The number of reciprocations of the wire 6 per minute (60 s) is referred to as the number of wire cycles. The number of wire cycles is, for example, 1 (times / min). Also, the time from when the speed of the wire 6 decreases until it temporarily stops, travels in the reverse direction, and reaches a predetermined constant speed is called a wire variable speed. The wire variable speed is, for example, 3 to 6 s. Moreover, the average value of the speed which the wire 6 drive | works is called a wire average linear velocity, for example, is 500-650 (m / min).

  As described above, the wire 6 cuts the silicon ingot 1 while reciprocating. Since the wire 6 wears as the time for reciprocating the wire 6 and cutting the silicon ingot 1 increases, the feeding reel 10 is renewed at a predetermined new wire supply rate (m / min) as will be described later. The wire 6 is fed out. The new wire 6 supplied from the feeding reel 10 is taken up by the take-up reel.

  The ingot 1 is bonded to a work plate 2 made of graphite. The work plate 2 is bonded to the set plate 3. When the ingot 1 is bonded to the work plate 2 and the work plate 2 is bonded to the set plate 3, the posture of the ingot 1 is adjusted so that the cutting direction of the ingot 1 coincides with the crystal plane. That is, the direction of the central axis of the ingot 1 is adjusted so that the crystal orientation of the ingot 1 is perpendicular to the cutting direction of the wire 6. The set plate 3 is attached to the lifting base 4. The elevating base 4 is moved up and down by the elevating drive motor 17.

  A slurry supply pipe 14 is disposed above the processing rollers 7 and 8. A supply port 14a is opened in the slurry supply pipe 14, and the slurry 30 including the abrasive grains 31 is discharged from the supply port 14a. The slurry supply pipe 14 is freely accessible in the vicinity of the cut portion of the ingot 1 by a moving mechanism.

  Here, the slurry 30 is, for example, mineral oil (PS-LW-50), a slurry specific gravity of 1.48 to 1.54 (g / cc), and a slurry viscosity of 160 to 260 (cp, 25 ° C., 20 rpm) is used. As for the grain size of the abrasive grain 31, for example, the one of # 2500 in JIS is used.

  The slurry 30 supplied to the cutting site between the wire 6 and the ingot 1 is collected in the slurry tank 15. The slurry 30 collected in the slurry tank 15 is sucked by the pump, discharged from the pump, and supplied to the slurry supply pipe 14 again. The slurry 30 absorbs heat generated when the ingot 1 is cut and rises in temperature. Therefore, the recovered slurry 30 is cooled to a certain temperature by a heat exchanger, and then the slurry supply pipe 14 is cooled. To be supplied.

  Next, a cutting operation performed by the wire saw device having the above-described configuration will be described.

  The lift drive motor 17 is driven and controlled, the lift base 4 is lowered, and the ingot 1 is pressed against the wire 6 between the pair of processing rollers 7 and 8. Further, the roller driving motor 13 is driven and controlled so that the wire 6 travels. Thereby, the cutting process of the ingot 1 is performed. At this time, the slurry supply pipe 14 is approaching the vicinity of the cutting portion of the ingot 1. The slurry 30 is supplied to the cutting part of the ingot 1 against which the wire 6 is pressed from the supply port 14a. For this reason, the ingot 1 is gradually cut by the lapping action. Since the wire 6 is wound at a predetermined pitch in the longitudinal axis direction of the processing rollers 7 and 8, the roller has a thickness corresponding to the pitch length and is pressed against the ingot 1 The number of silicon wafers 1 a corresponding to the number of windings 7 and 8 is generated from one ingot 1.

  The raising / lowering drive motor 17 is driven and controlled so that the cutting speed (μm / min) changes according to the progress of the cutting process of the ingot 1. The cutting start speed when cutting the outer periphery of the ingot 1 at the start of cutting, the cutting center speed when cutting the central portion of the ingot 1, and the outer periphery of the ingot 1 after cutting the central portion of the ingot 1 Different speeds are set for each stage, such as the cutting end speed when cutting. For example, the cutting start speed is 700 to 830 μm / min, the cutting center speed is 400 to 450 μm / min, and the cutting end speed is set to 400 to 620 μm / min.

  When the cutting process of the ingot 1 is completed, the elevating base 4 is raised, and the sliced ingot 1 is moved to the original retracted position. The cutting temperature is adjusted to a constant value of, for example, 25 ° C. or less, and one ingot 1 is cut in a cutting time of 6.5 (H / time), for example.

  Here, the relationship between the direction in which the wire 6 is wound around the rollers 7, 8, and 9 and the ingot 1 will be described with reference to FIG.

  As shown in FIG. 6A, the ingot 1 having the full length L is disposed along the longitudinal direction of the rollers 7, 8, and 9 as described above. Of both ends of the rollers 7, 8, 9, the end on the side where the new wire 6 is supplied is called the new line side, and the end on the side where the wire 6 used for cutting is taken up is called the winding side And Correspondingly, the end of the ingot 1 corresponding to the new line side of the rollers 7, 8, 9 is called the new line side, and the end of the ingot 1 corresponding to the winding side of the rollers 7, 8, 9 is It is called the winding side. A direction from the new line side to the winding side (a direction in which the wire 6 is wound) is referred to as a wire feeding direction, that is, a new line supply direction.

  As shown in FIG. 6B, the total length L of the ingot 1 to be cut includes L1, L2, and L3, which vary from short to long (L1 <L2 <L3).

  In some cases, the ingot 1 to be cut may be a single piece in which one ingot 1 is bonded to the work plate 2 (FIG. 6A). As shown in FIG. The ingots 1, 1 are arranged in a line along the longitudinal direction of the rollers 7, 8, 9 and are bonded to the work plate 2.

  As shown in FIG. 6 (c), in the two-ply bonding, the two ingots 1 and 1 are arranged in a line along the longitudinal direction of the rollers 7, 8, and 9. In this case, The “total length L” is defined by the distance L from the end surface of the ingot 1 (first) on the new line side to the end surface of the ingot 1 (second) on the winding side.

  Next, the present embodiment will be described in comparison with a comparative example. As the ingot 1 to be cut, those having lengths L1, L2, and L3 shown in FIG. 6B were used.

  FIG. 7A is a diagram for explaining a comparative example, and shows a variation in the thickness W of the wafer 1 a obtained at each part in the longitudinal direction of the ingot 1 in a graph.

  The horizontal axis of FIG. 7A shows each part of the ingot length direction with the new line side in the origin direction and the positive side in the winding side, and the vertical axis shows the thickness W of the wafer 1a. Yes.

  If the new wire supply amount does not change when the ingot 1 is cut, the wear amount of the wire 6 increases in proportion to the distance from the end surface of the ingot 1 on the new line side, as shown by the straight line C0. The wire diameter of the wire 6 is reduced. The slope of the straight line C0 corresponds to the amount of new line supply. As the new line supply amount increases, the wear amount of the wire 6 decreases, and the inclination of the straight line C0 decreases from the state shown in the figure.

  In the comparative example, the supply amount of the new line is constant regardless of the lengths L1, L2, and L3 of the ingot 1. For example, the wire 6 having a wire diameter of 0.14 mm was used, and the new wire supply rate (m / min) was constant at 130 (m / min). The slope of the straight line C0 has a magnitude corresponding to the new line supply amount value 130 (m / min).

In the case of an ingot of length L1, the thickness W of the wafer 1a gradually increases in proportion to the distance from the end face on the new line side from the end face on the new line side to the end face on the take-up side. The variation in the thickness W between the wafers 1a is ΔW1. Similarly, in the case of an ingot having a length L2, the variation in thickness W between the wafers 1a from the new wire side end surface to the winding side end surface of the ingot 1 is ΔW2, and in the case of an ingot having a length L3, The variation in the thickness W between the wafers 1a from the new wire side end surface of the ingot 1 to the winding side end surface is ΔW3.
Since the inclination of the straight line C0 is constant and the amount of wear of the wire 6 increases in proportion to the increase in the total length of the ingot 1, the length L1, L2, and L3 are sequentially increased as the total length of the ingot 1 increases. Thus, the variation in thickness between the wafers 1a sequentially increases as ΔW1, ΔW2, and ΔW3 (ΔW1 <ΔW2 <ΔW3).

  Here, it is assumed that the thickness variation value ΔW2 (below) is a reference level of the quality of the thickness variation. The wafers 1a obtained from the ingots 1 having the lengths L2 and L1 satisfy this quality standard level, but the wafers 1a obtained from the ingots 1 having the length L3 have a thickness variation ΔW3. It is large (ΔW3> ΔW2) and does not satisfy the quality standard level of thickness variation. On the contrary, the ingot 1 having a short length L1 is a result of unnecessarily supplying a new wire 6 more than necessary, which causes a reduction in manufacturing cost.

  On the other hand, FIG.7 (b) is a figure explaining a present Example with the graph corresponding to Fig.7 (a).

  In the case of the present embodiment, as shown in FIG. 7B, the wear amount of the wire 6 after the cutting process is constant regardless of the length of the ingot 1 or the thickness of the wafer 1a. As the length of the ingot 1 to be cut becomes smaller in order of L3, L2, and L1 so that the variation ΔW of the ingot 1 becomes constant (ΔW2) regardless of the length of the ingot 1, the new line supply amount decreases. Thus, the new line supply amount was set and the ingot 1 was cut (so that the slopes of the straight lines C3, C2, and C1 increased sequentially).

  In the present embodiment, for example, the amount of wear of the wire 6 falls within the range of 0.008 mm to 0.01 mm (8 μm to 10 μm) in terms of the reduction width of the wire diameter (wire diameter), so that the variation in the thickness of the wafer 1a varies. The new line supply amount was set according to the length of the ingot 1 so as to be within the range near the quality reference level ΔW2.

  For example, when the wire 6 having a wire diameter of 0.14 mm is used, the new wire supply amount (m / min) is set according to the ingot length in the correspondence shown in FIG. In addition, when the wire 6 having a wire diameter of φ0.12 mm is used, the new wire supply amount (m / min) is set according to the ingot length in the correspondence shown in FIG. Further, as can be seen by comparing FIG. 8A and FIG. 8B, the new line supply amount is increased as the wire diameter of the wire 6 is reduced from φ0.14 mm to φ0.12 mm.

  As a result, as shown by straight lines C3, C2, and C1 in FIG. 7B, the slope of the straight line increases as the total length of the ingot 1 decreases (L3 → L2 → L1). Regardless of the total length, the amount of wear of the wire 6 is stabilized, and the variation in thickness between the wafers 1a obtained from the ingots of each length is stabilized at a value of ΔW2.

  In the above description, the single ingot 1 has been described. However, when the two ingots 1 and 1 are cut, the total length L of the ingots 1 and 1 in the case of two sticks (FIG. 6 ( The new line supply amount may be set similarly in accordance with c)).

  Therefore, according to the present embodiment, the length of the ingot 1 is not affected, the quality standard level of the thickness variation is satisfied, and the quality related to the thickness variation is stabilized regardless of the length of the ingot 1. Moreover, about the ingot 1 of short length L1, since cutting is performed with the supply amount smaller than the conventional new line supply amount, a manufacturing cost is reduced.

  The following shows the simulation results of the wire usage of each of the comparative example and the present example.

(Comparative example)
Wire diameter: 0.14mm
New line supply: 130m / min (constant)
Wire usage: 31217 km / month (Example)
Wire diameter: 0.14mm
New line supply: Fluctuates according to ingot length (according to Fig. 8 (a))
Wire usage: 26744 km / month Thus, according to this example, it is confirmed that the usage of wire 6 per month is reduced by 4473 km compared to the comparative example, and the manufacturing cost is drastically reduced. It was done.

  In addition, as described above, as a result of changing the new line supply amount according to the length of the ingot so as to make the variation in the thickness of the wafer 1a constant, the quality related to warp, swell, etc. also varies between the wafers 1a. The variation of the has decreased and became stable.

FIGS. 1A and 1B are diagrams for explaining kerf loss and conceptually showing how an ingot is cut into a wafer by a wire. FIG. 2 is a diagram for explaining the swell. FIG. 3 is a diagram for explaining warp. FIG. 4 is a perspective view showing the configuration of the wire saw device of the embodiment. FIG. 5 is a diagram showing a state where the silicon ingot is cut by the wire, and is a view of the silicon ingot viewed from the cut surface direction. 6A, 6 </ b> B, and 6 </ b> C are diagrams illustrating the positional relationship between the roller and the ingot. FIG. 7 is a graph showing the relationship between the distance (ingot length) from the end surface on the new line side of the ingot and the thickness of the wafer, corresponding to the ingots of different lengths, and FIG. It is a graph of a comparative example, FIG.7 (b) is a graph of an Example. 8A and 8B are tables illustrating the correspondence between the ingot length and the new line supply amount.

Explanation of symbols

  1 Silicon Ingot 1a Silicon Wafer 6 Wire

Claims (3)

In a workpiece cutting method in which a new wire is supplied at a predetermined new wire supply amount, and the workpiece is moved relative to a wire that is wound around a roller in the direction of pressing to cut the workpiece into a thin plate. ,
New line supply amount so that the amount of new wire supply decreases as the length of the workpiece to be cut decreases so that the amount of wire wear after cutting is constant regardless of the length of the workpiece. A method of cutting a workpiece with a wire that is set to cut the workpiece. In a workpiece cutting method in which a new wire is supplied at a predetermined new wire supply amount, and the workpiece is moved relative to a wire that is wound around a roller in the direction of pressing to cut the workpiece into a thin plate. ,
Set the new line supply amount so that the variation in the thickness of the thin plate is constant regardless of the length of the workpiece, and the new line supply amount decreases as the length of the workpiece to be cut decreases. A method of cutting a workpiece with a wire that cuts the workpiece. The method for cutting a workpiece with a wire according to claim 1, wherein the workpiece is a semiconductor ingot, and the thin plate is a semiconductor wafer.

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