TWI620840B - Slicing apparatus for silicon carbide ingot and slicing method for silicon carbide ingot - Google Patents

Abstract

A silicon carbide crystal rod slicing device includes a swing-type wire cutting device and a table for fixing the silicon carbide crystal rod. The swing type wire cutting device includes a fixed seat, a swinging table provided on the fixed seat and capable of relatively swinging, a plurality of rollers, and a cutting line movably wound around the plurality of rollers at a linear speed of at least 1510 meters / minute. The plurality of rollers collectively define a slicing channel through which the silicon carbide crystal rod passes, and the positions of the cutting lines on the slicing channel are arranged parallel to each other and are defined as a plurality of operating line segments. During the process of the silicon carbide crystal rod being cut by multiple actuation line segments, the swinging table swings relative to the fixed seat, and the table can move at an adjustable feed speed, and the adjustable feed speed is gradually reduced from the initial speed to the minimum speed , And then gradually increase to the final speed.

Description

Silicon carbide crystal rod slicing equipment and method

The invention relates to a slicing device and a slicing method, in particular to a silicon carbide rod slicing device and a slicing method of a silicon carbide rod.

At present, the slicing equipment for cutting ingots can be divided into two fields according to different working principles: one is a free mortar slice and the other is a fixed wire slice. The following briefly discusses the respective cutting working principles of the above two fields.

First, as shown in FIG. 1, in the field of free mortar slicing, the cost of the slicing equipment is relatively low, but when cutting the ingot 1a, the slicing equipment drives the silicon carbide particles 31a in the cutting liquid 3a through the wire 2a Rolling and further cutting the ingot 1a in a continuous manner easily cause unevenness in the thickness of the wafer. What's more, the cut portion of the ingot 1a is liable to generate debris, which further increases the difficulty of recycling the silicon carbide particles 31a, causing waste of resources and environmental pollution. Furthermore, as shown in FIG. 2, in the field of fixed wire slicing, the cost of the slicing equipment is relatively high but time-saving. When the ingot 1a is cut, the slicing equipment penetrates the cutting particles on the cutting line 4a. 41a (eg, diamond particles) cuts the ingot 1a and cools it with the cooling liquid 5a, so as to generate a uniform and thin wafer.

However, in the field of fixed wire slicing, the existing slicing equipment and operations for silicon carbide ingots mostly use line speeds from 400 m / min to 700 m / min, which results in poor slice quality of silicon carbide . However, if the existing slicing equipment is upgraded with The linear speed of the operation can easily cause problems such as cutting line breakage.

Therefore, the present inventor believes that the above-mentioned defects can be improved, and with special research and cooperation with the application of scientific principles, he finally proposes an invention with a reasonable design and effective improvement of the above-mentioned defects.

The embodiments of the present invention provide a silicon carbide ingot slicing device and a method for slicing silicon carbide ingots, which are used to effectively improve defects that may occur in existing slicing equipment and operations.

The embodiment of the invention discloses a silicon carbide ingot slicing device for slicing a cylindrical silicon carbide ingot. The silicon carbide ingot slicing device includes a swinging wire cutting device including a fixing base. A swinging table arranged on the fixed seat, and the swinging table can swing relative to the fixed seat; a plurality of rollers collectively define a slice channel for the silicon carbide crystal rod to pass through, The roller can be mounted on the swinging table in a self-rotating manner and the fixed position relative to the swinging table is fixed; and a cutting line includes a core line and a plurality of cutting particles fixed on the core line, the cutting line It is movably wound around a plurality of the rollers at a linear speed of at least 1510 meters / minute, and a portion of the cutting line on the slicing channel is defined as a plurality of actuation line segments, and the plurality of actuation line segments are parallel to each other Are arranged at an interval from the ground; and a table for fixing the silicon carbide ingot; wherein, in the process that the silicon carbide ingot starts to be cut by a plurality of the operating line segments, the swing stage is phased Swung to the fixing base, the table can be moved at a feed rate adjustment formula and the adjustment formula is the feed rate is gradually reduced from an initial speed to a minimum speed, and then gradually increased to a final velocity.

An embodiment of the present invention also discloses a method for slicing a silicon carbide ingot, which includes: using the silicon carbide ingot slicing device as described above, and fixing a cylindrical silicon carbide ingot to the workbench; wherein, the The silicon carbide rod is divided into a front section, a middle section, and a final section along its radial direction; the cutting line is maintained at a line speed of at least 1510 meters per minute to operate, and the swing table is relatively Mentioned fixed base swing; Moving the table in the direction of a plurality of the actuating line segments; and when the silicon carbide crystal rod is cut by the plurality of the actuating line segments, moving the table at an adjustable feed rate so that The front section, the middle section, and the last section of the silicon carbide ingot are sequentially cut by a plurality of the actuation line sections to form a plurality of wafers, wherein the adjustable feed rate is determined by a The initial speed is gradually reduced to a minimum speed and then gradually increased to a final speed.

In summary, the silicon carbide ingot slicing device and the method for slicing silicon carbide ingots disclosed in the embodiments of the present invention use a swinging table to swing relative to a fixed seat, and cooperate with a table to move at an adjustable feed rate, so that carbonization The silicon rod can be sliced at a high-speed line speed, so that the cutting quality of the silicon carbide rod can be effectively improved without the cutting line breaking easily.

In order to further understand the features and technical contents of the present invention, please refer to the following detailed description and drawings of the present invention, but these descriptions and drawings are only used to illustrate the present invention, and not to make any limitation to the protection scope of the present invention. limit.

[current technology]

1a‧‧‧ ingot

2a‧‧‧Wire

3a‧‧‧ cutting fluid

31a‧‧‧Silicon carbide particles

4a‧‧‧cut line

41a‧‧‧cutting particles

5a‧‧‧ Coolant

[Examples of the invention]

100‧‧‧Silicon Carbide Ingot Slicing Equipment

1‧‧‧ rocking wire cutting device

11‧‧‧Fixed

12‧‧‧Swing table

13‧‧‧roller

131‧‧‧ Slice Channel

14‧‧‧cut line

141‧‧‧core

142‧‧‧cut particles

143‧‧‧action line segment

2‧‧‧Workbench

200‧‧‧ Silicon Carbide Ingot

201‧‧‧front

202‧‧‧ middle

203‧‧‧last paragraph

204‧‧‧Chip

G‧‧‧Pitch

D1, D2‧‧‧ diameter

T1‧‧‧ predetermined thickness

T2‧‧‧actual thickness

FIG. 1 is a partial schematic view of a cutting device for cutting a crystal rod in a conventional free mortar slicing field.

FIG. 2 is a partial schematic view of a cutting device for cutting a crystal rod in a conventional fixed wire slicing field.

FIG. 3 is a schematic perspective view of a silicon carbide ingot slicing device according to the present invention.

FIG. 4 is a partial schematic view of a cutting line of a silicon carbide ingot slicing device according to the present invention.

FIG. 5 is a schematic top view of FIG. 3.

FIG. 6 is a schematic diagram of steps a and b of a slicing method of a silicon carbide ingot according to the present invention.

FIG. 7 is a schematic diagram of step c of a slicing method of a silicon carbide ingot according to the present invention.

8 and 9 are schematic diagrams of step d of a method for slicing a silicon carbide ingot according to the present invention.

FIG. 10 is a schematic diagram of a table feed rate in step d of a method for slicing a silicon carbide ingot according to the present invention.

FIG. 11 is a schematic diagram of a wafer formed by a silicon carbide crystal rod through the above steps a to d.

FIG. 12 is a schematic side view of the wafer in FIG. 11.

Please refer to FIGS. 3 to 12, which are embodiments of the present invention. It should be noted that this embodiment corresponds to the related quantities and appearances mentioned in the drawings, and is only used to specifically describe the embodiments of the present invention in order to In order to understand the content of the present invention, it is not intended to limit the protection scope of the present invention.

Wherein, this embodiment discloses a silicon carbide ingot slicing device 100 and a silicon carbide ingot slicing method. In order to facilitate a clear understanding of this embodiment, the following will first describe the silicon carbide ingot slicing device 100, and then continue to introduce A method for slicing a silicon carbide crystal rod.

As shown in FIG. 3 to FIG. 5, the silicon carbide ingot slicing device 100 is used to perform a slicing operation on a cylindrical silicon carbide ingot 200 (such as a single-crystal silicon carbide ingot), and the above silicon carbide ingot 200 The thickness is, for example, more than 7 mm, but is not limited thereto. That is, the silicon carbide ingot slicing device 100 of this embodiment is any slicing device (not shown in the figure) excluding any slicing device not used for cutting silicon carbide ingots. The silicon carbide ingot slicing device 100 includes a swinging wire cutting device 1 and a worktable 2 for performing the slicing operation in cooperation with the swinging wire cutting device 1.

The swing type wire cutting device 1 includes a fixed base 11, a swinging table 12, a plurality of rollers 13, and a cutting line 14. Wherein, the fixed base 11 is kept stationary, the swinging table 12 is disposed on the fixed base 11, and the swinging table 12 can swing relative to the fixed base 11. The above-mentioned swinging direction is, for example, the swinging table 12 swings back and forth in a clockwise direction and a counterclockwise direction with its center as the rotation center, but the present invention is not limited thereto.

Each of the rollers 13 is concavely provided with a plurality of annular (or spiral) grooves (not shown), and the grooves of the plurality of rollers 13 correspond to each other. The roller 13 of this embodiment is composed of a metal shaft center and a polymer layer covered on the metal shaft center as an example. But not limited to this. Furthermore, the plurality of rollers 13 collectively define a slicing channel 131 (eg, the above-mentioned slicing channel 131 is formed between the two rollers 13 located above in FIG. 3), and the slicing channel 131 is used for silicon carbide crystals. Stick 200 passed. Wherein, each of the rollers 13 is capable of being mounted on the swinging table 12 so as to be capable of self-rotation, and the relative position with the swinging table 12 is kept fixed.

The cutting wire 14 includes a core wire 141 and a plurality of cutting particles 142 fixed on the core wire 141. The cutting wire 14 in this embodiment may be an electroformed type, a resin type, or other types that can fix the cutting particles 142 to the outer edge of the core wire 141. The core wire 141 has a diameter D1 of 100 micrometers (μm) to 120. The maximum wire diameter D2 of the cutting wire 14 (for example, the sum of the wire diameter D1 of the core wire 141 and the maximum outer diameter of the cutting particles 142 thereon) is less than 200 micrometers, but not limited thereto. Moreover, in this embodiment, the cutting particles 142 are preferably diamond particles.

Further, the cutting line 14 is movably wound in a groove of a plurality of rollers 13 at a line speed of at least 1510 meters per minute (m / min), and the cutting line 14 is located on the slicing channel 131. The position of is defined as a plurality of actuation line segments 143. Among them, the cutting line 14 is preferably movably wound around the grooves of the plurality of rollers 13 at a linear speed of 1800 m / min to 2800 m / min. Furthermore, the plurality of actuation line segments 143 are adjacent to the table 2 and are located substantially on the same plane. The plurality of actuation line segments 143 are arranged in parallel and spaced apart from each other, and the distance G between two adjacent actuation line segments 143 is preferably in this embodiment. 0.7 ± 0.15 mm (mm), but not limited to this. For example, the above-mentioned pitch G may be less than 0.7 mm.

The worktable 2 is used for fixing the silicon carbide crystal rod 200 and can be moved in the direction of a plurality of operating line segments 143 (or slicing channels 131). It should be noted that, in the process that the silicon carbide crystal rod 200 starts to be cut by the multiple actuating line segments 143, the swinging table 12 is swung relative to the fixed seat 11, and the worktable 2 can be adjusted in an adjustable manner. The feed speed moves, and the adjustable feed speed is gradually reduced from an initial speed to a minimum speed, and then gradually increased to a final speed. In this embodiment, the initial speed is greater than the final speed, and the minimum speed is preferably not small. At 6 mm / hr.

The above is a description of the structure and function of the silicon carbide ingot slicing device 100 of this embodiment, and then please refer to FIG. 6 to FIG. 9, which are schematic diagrams of the slicing method of the silicon carbide ingot of this embodiment. And Table 2 below are some specific experimental data of this embodiment.

Step a: As shown in FIG. 6, the silicon carbide ingot slicing device 100 described above is used, and a cylindrical silicon carbide ingot 200 is fixed on the bottom edge of the worktable 2 so that the silicon carbide ingot 200 The long side edge of is the plurality of operating line segments 143 (or slicing channels 131) facing the silicon carbide ingot slicing device 100 described above. The silicon carbide rod 200 is divided into a front section 201, a middle section 202, and a final section 203 along its radial direction. The front section 201 of the silicon carbide rod 200 is adjacent to the plurality of actuation line segments 143 (or slicing channels 131) and is far from the table 2. The end section 203 is far from the plurality of actuation line segments 143 (or slicing channels 131) and is fixed to the table. 2.

Step b: As shown in FIG. 6, the cutting line 14 is maintained at a linear speed of at least 1510 meters / minute, and the swinging table 12 is swung relative to the fixed base 11. The cutting line 14 is preferably operated at a linear speed of 1800 m / min to 2800 m / min, but the present invention is not limited thereto.

Step c: As shown in FIG. 7, the workbench 2 is moved in the direction of the plurality of operating line segments 143 until the silicon carbide ingot 200 on the worktable 2 is ready to contact the operating line segments 143 of the cutting line 14. That is, there is no restriction on the moving speed of the table 2 in this step c.

Step d: As shown in FIG. 8 and FIG. 9, when the silicon carbide crystal rod 200 starts to be cut by the plurality of actuation line segments 143, the table 2 is moved at an adjustable feed rate to make the silicon carbide crystal The front section 201, the middle section 202, and the last section 203 of the rod 200 are sequentially cut by the plurality of actuation line segments 143 to form a plurality of wafers 204 (see FIG. 11). The adjustable feed speed is gradually reduced from an initial speed to a minimum speed, and then gradually increased to a final speed. The initial speed is greater than the Final speed, and the minimum speed is not less than 6 mm / hour.

In more detail, the front section 201, the middle section 202, and the last section 203 of the silicon carbide ingot 200 are further divided into a plurality of sub-sections (not shown in the figure), and each sub-section corresponds to the adjustment. A value for the formula feed rate. For example, as shown in Table 1 below, in this embodiment, the silicon carbide rod 200 is roughly divided into 20 sub-sections along its radial direction, which includes the front section -1 to the front section 5, and the middle section -6 to the middle section -13. , The last segment -14 to the last segment -20, but the actual division of the sub-segments of the silicon carbide ingot 200 is not limited thereto.

Among them, please refer to FIG. 10, the first sub-section of the front section 201 corresponds to the initial speed (12 mm / hr corresponding to the first section-1 in the following Table 1), and the middle sub-section of the middle section 202 Is corresponding to the minimum speed (6mm / hr corresponding to the middle section -10 in Table 1 below), and the last sub-section of the last section 203 is corresponding to the final speed (the bottom section in Table 1 below 10mm / hr corresponding to segment-20). To put it another way, when the cutting line 14 is performing the slicing operation of the silicon carbide ingot 200, if the theoretical cutting area per unit time is small (such as the previous paragraph -1), the required amount of the cutting line 14 is also It is smaller, so the adjustment feed speed can be relatively high speed. Conversely, if the theoretical cutting area per unit time is large (such as: middle section -10), the amount of cutting wire 14 required is larger, so the adjustment feed The feed speed must be relatively low.

With this, the silicon carbide ingot slicing device 100 and the silicon carbide ingot slicing method disclosed in this embodiment are moved relative to the fixed base 11 by the swinging table 12 and are moved at an adjustable feed rate in cooperation with the table 2 so that The silicon carbide ingot 200 can perform the slicing operation at a high-speed linear speed, thereby effectively improving the slicing quality of the silicon carbide ingot 200. For example, the total thickness variation (TTV) of the wafer 204 produced by the slicing method of the silicon carbide ingot in this embodiment is less than 5 microns, the warp is less than 20 microns, and the amount of bow ( bow) is less than 10 microns.

Further, as shown in FIG. 11 and FIG. 12, since this embodiment can provide better Slice quality, so the thickness (eg, T2-T1) of each wafer 204 to be trimmed is relatively reduced. Therefore, the silicon carbide rod slicing device 100 can further control (reduce) the distance G between two adjacent operating line segments 143, thereby increasing the number of wafers 204 produced by each silicon carbide rod 200.

For example, each of the wafers 204 is preset with a predetermined thickness T1 (such as 350 micrometers required by the customer), and the gap G between two adjacent operating line segments 143 can be adjusted to 0.7 ± 0.15 mm (or less than 0.7 mm). ), So that an actual thickness T2 of each wafer 204 formed by cutting the silicon carbide ingot 200 can be no greater than 150 micrometers of the predetermined thickness T1. That is, the thickness of the wafer 204 generated by the slicing method of the silicon carbide ingot in this embodiment needs to be trimmed and removed (eg, T2-T1) to be within 150 microns.

In addition, the actual thickness T2 of the wafer 204 can be maintained at 100 micrometers or less than the predetermined thickness T1 in the preferred embodiment of the present invention (Experimental Group B in Table 2 below), thereby greatly increasing each carbonization. The number of wafers 204 produced by the silicon rod 200 is not limited thereto.

In addition, in an unillustrated embodiment, the silicon carbide ingot slicing device 100 can also be used to cut at least two silicon carbide ingots 200 stacked on each other, and in order to verify the feasibility, the present invention uses the above carbonization The silicon rod cutting device 100 performs cutting experiments on two silicon carbide rods 200 stacked on each other, and presents related parameters and results in the experimental group C in Table 2 below.

Among them, it can be known from the comparison between the experimental group B and the experimental group C in Table 2 below that the main difference between the two results or effects lies in the number of wafers produced by the wafers 204 and the amount of lines used by each wafer 204. There is not much difference in the remaining results or effects (such as: the difference between the actual thickness T2 of the wafer 204 and the predetermined thickness T1 or the yield of the wafer 204, etc.). Accordingly, after the silicon carbide ingot slicing device 100 and the silicon carbide ingot slicing method of the present invention are actually verified, they are indeed applicable to at least two silicon carbide ingots 200 stacked on each other.

[Technical effect of the embodiment of the present invention]

In summary, the silicon carbide ingot slicing device and the method for slicing silicon carbide ingots disclosed in the embodiments of the present invention use a swinging table to swing relative to a fixed seat, and cooperate with a table to move at an adjustable feed rate, so that carbonization occurs. The silicon rod can be sliced at a high-speed linear speed (at least 1510 meters / minute), so that the cutting quality of the silicon carbide rod can be effectively improved without cutting the cutting line easily.

In addition, since the silicon carbide ingot slicing device and the silicon carbide ingot slicing method according to the embodiments of the present invention can have better slicing quality, the distance between two adjacent action line segments (eg, 0.7 ± 0.15 mm) can be further controlled. ) To increase the number of wafers produced per silicon carbide ingot.

The above are only the preferred and feasible embodiments of the present invention, and are not intended to limit the scope of protection of the present invention. Any equal changes and modifications made in accordance with the scope of patent application of the present invention shall fall within the protection scope of the claims of the present invention. .

Claims (10)

A silicon carbide ingot slicing device is used for slicing a cylindrical silicon carbide ingot. The silicon carbide ingot slicing device includes: a swinging wire cutting device, including: a fixed seat; a swinging table, The roller is arranged on the fixed base, and the swinging table can swing relative to the fixed base; a plurality of rollers collectively define a slicing channel for the silicon carbide crystal rods to pass through, and each of the rollers can be itself It is rotatably installed on the swinging table and keeps its relative position fixed with the swinging table; and a cutting line including a core line and a plurality of cutting particles fixed on the core line, the cutting line is at least 1510 meters A linear velocity per minute is movably wound around a plurality of the rollers, and a portion of the cutting line on the slicing channel is defined as a plurality of actuation line segments, and the plurality of actuation line segments are arranged parallel to and spaced from each other; A worktable is used to fix the silicon carbide ingot; in the process that the silicon carbide ingot starts to be cut by a plurality of the operating line segments, the swinging table is moved relative to the fixed seat. Swinging back and forth, to enter the table at a speed-adjusting movement, the adjustment formula and the feed rate was gradually reduced from an initial speed to a minimum speed, and then gradually increased to a final velocity. The silicon carbide ingot slicing device according to claim 1, wherein a distance between two adjacent operation line segments is 0.7 ± 0.15 mm. The silicon carbide ingot slicing device according to claim 1, wherein a wire diameter of the core wire is 100 micrometers to 120 micrometers, and a maximum wire diameter of the cutting wire is less than 200 micrometers. The silicon carbide ingot slicing device according to claim 1, wherein the cutting line is movably wound around a plurality of the rollers at a line speed of 1800 m / min to 2800 m / min. The silicon carbide ingot slicing device according to any one of claims 1 to 4, wherein the initial speed is greater than the final speed, and the minimum speed is not less than 6 mm / hour. A method for slicing silicon carbide crystal rods, comprising: using the silicon carbide crystal rod slicing equipment according to claim 1, and fixing a cylindrical silicon carbide crystal rod to the table; wherein the silicon carbide crystal The rod is divided into a front section, a middle section, and a final section along its radial direction; the cutting line is maintained at a linear speed of at least 1510 meters per minute for operation, and the swinging table is relative to the fixed seat Swing back and forth back and forth; move the table in the direction of a plurality of the actuating line segments; and when the silicon carbide ingot begins to be cut by a plurality of the actuating line segments, advance the table in an adjustable manner Moving at a speed such that the front section, the middle section, and the last section of the silicon carbide ingot are sequentially cut by a plurality of the actuation line segments to form a plurality of wafers; wherein the adjustment type The feed speed is gradually reduced from an initial speed to a minimum speed, and then gradually increased to a final speed. The method for slicing a silicon carbide ingot according to claim 6, wherein each of the wafers is preset with a predetermined thickness, and a distance between two adjacent action line segments is 0.7 ± 0.15 mm, so that the Each of the wafers formed by cutting a silicon carbide ingot has an actual thickness not greater than the predetermined thickness of 150 micrometers. The method for slicing a silicon carbide ingot according to claim 7, wherein a wire diameter of the core wire is 100 μm to 120 μm, and a maximum wire diameter of the cutting wire is less than 200 μm. The method for slicing a silicon carbide ingot according to claim 6, wherein the cutting line is operated at a line speed maintained at a line speed of 1800 m / min to 2800 m / min. The method for slicing a silicon carbide ingot according to any one of claims 6 to 9, wherein the front section, the middle section, and the last section are each further divided into a plurality of subsections, and each of the sections The sub-section is a section corresponding to the adjustable feed rate. Number, the first sub-section of the front section corresponds to the initial speed, the middle sub-section of the middle section corresponds to the lowest speed, and the last The sub-section corresponds to the final speed; wherein the initial speed is greater than the final speed, and the minimum speed is not less than 6 mm / hour.