TWI842478B - Apparatus and method for manufacturing semiconductor crystal wafer - Google Patents

Abstract

An object of the present invention is to provide an apparatus and a method for manufacturing semiconductor crystal wafer, which can simply and certainly manufacture semiconductor crystal wafers with high quality. A method for manufacturing a SiC wafer that is a semiconductor crystal wafer includes a groove processing step (STEP100/FIG. 1), a grinding step (STEP110/FIG. 1), a cutting step (STEP 120/FIG. 1), a first surface processing step (STEP130/FIG.1), and a second surface processing step (STEP140/FIG. 1); in the cutting step, before cutting a SiC ingot 10 into slices by rotating and advancing at the same time a plurality of wires 42 disposed in a plurality of concave grooves 11, the plurality of wires 42 arranged in the plurality of concave grooves 11 are photographed by a photographing means 44 which is provided at a positon where the photographing means 44 is opposite to an ingot supporting means 43 for supporting the SiC ingot 10 with the plurality of wires 42 interposed therebetween, a deviation angle of the plurality of wires 42 with respect to the plurality of concave groove 11 is detected from the photographed image obtained by the photographing means 44, and the deviation angle is adjusted to become zero.

Description

Semiconductor crystal wafer manufacturing device and manufacturing method

The present invention relates to a semiconductor crystal wafer manufacturing device and manufacturing method for cutting a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape.

Conventionally, as for the manufacturing method of this type of SiC wafer belonging to semiconductor crystal wafer, as shown in the following patent document 1, there is known a manufacturing method of SiC wafer including a wafer shape forming step, a subsequent processing altered layer removal step, and a final mirror polishing step. The wafer shape forming step includes, for example, an ingot forming step, processing a single crystal SiC block grown by crystallization into a cylindrical ingot; a crystal orientation forming step, forming a notch at a portion of the outer periphery of the ingot to form a mark indicating the crystal orientation of the ingot; a slicing step, slicing a single crystal SiC ingot to form a thin disk-shaped SiC wafer; a flattening step, flattening the SiC wafer using abrasive grains that do not reach the modified Mohs hardness; a mark forming step of forming a mark; and a chamfering step of chamfering the outer periphery. As for the process-deteriorated layer removal step, for example, the process-deteriorated layer formed in the SiC wafer in the previous step is removed. In the mirror polishing step, for example, a chemical mechanical polishing (CMP) step is used to polish by combining the mechanical action of a polishing pad with the chemical action of a slurry.

(Prior technical literature)

(Patent Literature)

Patent document 1: Japanese Patent Publication No. 2020-15646

However, the above-mentioned known SiC wafer manufacturing method has the problems of multiple and complex processes, complex device structure and high manufacturing cost.

On the other hand, if the process is simplified, it will be difficult to stably obtain the quality required for SiC wafers.

In view of this, the purpose of the present invention is to provide a semiconductor crystal wafer manufacturing device and manufacturing method that can easily and reliably manufacture high-quality semiconductor crystal wafers.

The semiconductor crystal wafer manufacturing device of the first invention is to cut a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape, and the semiconductor crystal wafer manufacturing device is equipped with:

The groove processing drum grindstone is used to form a plurality of grooves surrounding the entire side surface of the aforementioned semiconductor crystal ingot, and a plurality of convex portions corresponding to the plurality of grooves are formed on the side surface;

The wire saw device causes the plurality of wires arranged in the plurality of grooves to rotate and move forward simultaneously, thereby cutting the semiconductor crystal ingot into sheets;

The imaging means is to photograph the plurality of lines arranged in the plurality of grooves in the wire saw device at a position facing the ingot support means supporting the semiconductor crystal ingot across the plurality of lines; and

The slide is provided with the aforementioned photographing means at the front end side, which can make the photographing means move from the frame of the aforementioned wire saw device toward the aforementioned position for photographing, and retreat after photographing; wherein,

Detect the deviation angles of the aforementioned plurality of lines relative to the aforementioned plurality of grooves from the photographic image obtained by the aforementioned photographic means.

The semiconductor crystal wafer manufacturing device of the second invention is to cut a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape, and the semiconductor crystal wafer manufacturing device is equipped with:

The groove processing drum grindstone is used to form a plurality of grooves surrounding the entire side surface of the aforementioned semiconductor crystal ingot, and a plurality of convex portions corresponding to the plurality of grooves are formed on the side surface;

The wire saw device causes the plurality of wires arranged in the plurality of grooves to rotate and move forward simultaneously, thereby cutting the semiconductor crystal ingot into sheets;

The imaging means is to photograph the plurality of lines arranged in the plurality of grooves in the wire saw device at a position facing the ingot supporting means supporting the semiconductor crystal ingot across the plurality of lines;

The slider is provided with the aforementioned photographing means at the front end side, and can make the photographing means move toward the aforementioned position for photographing; and

The installation and disassembly means can freely install and disassemble the aforementioned sliding member on the aforementioned wire saw device; wherein,

Detect the deviation angles of the aforementioned plurality of lines relative to the aforementioned plurality of grooves from the photographic image obtained by the aforementioned photographic means.

The semiconductor crystal wafer manufacturing device according to the first invention or the second invention is composed of a groove processing drum grindstone and an additional component corresponding to the groove processing drum grindstone. The groove processing drum grindstone is used to form a plurality of grooves surrounding the entire side surface of the semiconductor crystal ingot, and a plurality of convex portions corresponding to the plurality of grooves are formed on the side surface.

The first additional component is a wire saw device that rotates a plurality of wires arranged in a plurality of grooves formed on the entire side surface of the semiconductor crystal ingot.

The second additional component is a photographing means, which is provided in the wire saw device at a position facing the ingot supporting means supporting the semiconductor crystal ingot across the aforementioned plurality of lines, and photographs the plurality of lines arranged in the aforementioned plurality of grooves. Furthermore, the photographing means has a slider, and the slider moves the photographing means toward the position where the photographing is performed. Furthermore, the second invention has a mounting and dismounting means, and the mounting and dismounting means can freely mount and dismount the slider on the wire saw device.

In the above structure, for the multiple grooves formed on the entire side surface of the semiconductor crystal ingot by the groove processing drum grindstone, the multiple lines are correctly arranged in the multiple grooves, and the semiconductor crystal ingot can be cut into sheets with good precision along the multiple lines.

Here, in order to correctly arrange the plurality of lines on the plurality of grooves, the deviation angle of the moving direction of the plurality of lines relative to the moving direction (long side direction) of the plurality of grooves is detected from the photographic image obtained by the photographic means.

Therefore, the deviation angle can be accurately grasped, for example, the support means of the semiconductor crystal ingot can be adjusted, the wire saw wire axis can be adjusted, etc., to offset the deviation angle. Moreover, after the adjustment, In the first invention, the camera means can be retracted by the slider, and in the second invention, the slider itself with the camera means set at the front end can be disassembled so that the camera means and the slider will not cause interference in the subsequent steps (for example, the cutting step).

Thus, according to the semiconductor crystal wafer manufacturing device of the first invention or the second invention, semiconductor crystal ingots can be cut into sheets with good precision, and high-quality semiconductor crystal wafers can be manufactured simply and reliably.

The semiconductor crystal wafer manufacturing device of the third invention is the first invention or the second invention, wherein the slide member slides the imaging means at the aforementioned position, and the imaging means continuously photographs the plurality of lines arranged in the plurality of grooves.

According to the semiconductor crystal wafer manufacturing device of the third invention, the photographing means is slid by a slider, and even if a single shot cannot capture all the multiple lines of the multiple grooves in the photographic image, the deviation angles of all the multiple lines relative to the multiple grooves can be detected and adjusted by scanning and continuously photographing.

Thus, according to the semiconductor crystal wafer manufacturing device of the third invention, semiconductor crystal ingots can be cut into sheets with better precision, and high-quality semiconductor crystal wafers can be manufactured simply and reliably.

The semiconductor crystal wafer manufacturing device of the fourth invention is the first invention or the second invention, wherein the ingot supporting means has a deviation angle adjusting means, and the deviation angle adjusting means rotates and fixes the semiconductor crystal ingot in such a manner that the deviation angle detected from the photographic image obtained by the photographic means becomes zero.

According to the semiconductor crystal wafer manufacturing device of the fourth invention, the semiconductor crystal ingot can be fixed at a matching position by rotating the semiconductor crystal ingot in a manner such that the deviation angle is offset to zero, by means of a deviation angle adjustment means configured in the ingot support means, which rotates around a rotation axis extending perpendicularly to the cut surface caused by a plurality of lines as the center and fixes the semiconductor crystal ingot at a position where the deviation angle becomes zero.

Thereby, the deviation angle of the running direction of the plurality of lines relative to the running direction (long side direction) of the plurality of grooves becomes zero, and the plurality of lines can be correctly arranged in the plurality of grooves.

Thus, according to the semiconductor crystal wafer manufacturing device of the fourth invention, semiconductor crystal ingots can be cut into slices with good precision using a simple structure, and high-quality semiconductor crystal wafers can be manufactured simply and reliably.

The fifth invention is a method for manufacturing a semiconductor crystal wafer, which is to cut a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape. The method for manufacturing a semiconductor crystal wafer comprises:

The groove processing step is to form a plurality of grooves surrounding the entire side surface of the aforementioned semiconductor crystal ingot; and

The cutting step is to use a wire saw device to make the multiple wires arranged in the multiple grooves formed in the aforementioned groove processing step rotate and move forward simultaneously, thereby cutting the aforementioned semiconductor crystal ingot into sheets;

In the aforementioned groove processing step, the groove processing drum grindstone having a plurality of convex portions corresponding to the aforementioned plurality of concave grooves formed on the side surface and the aforementioned semiconductor crystal ingot are respectively rotated on mutually parallel rotation axes, and the aforementioned groove processing drum grindstone is pressed against the aforementioned semiconductor crystal ingot to form the groove;

In the aforementioned cutting step, before the plurality of wires arranged in the plurality of grooves are rotated and simultaneously advanced to cut the aforementioned semiconductor crystal ingot into sheets, a slider having a camera means provided at the front end is moved from the frame of the aforementioned wire saw device, and the plurality of wires arranged in the plurality of grooves are photographed by the camera means at a position facing the ingot support means supporting the aforementioned semiconductor crystal ingot across the plurality of wires, and the deviation angle of the plurality of wires relative to the plurality of grooves is detected from the photographed image, and the deviation angle is adjusted to zero, and after adjusting the deviation angle, the aforementioned slider is retreated to avoid.

The sixth invention is a method for manufacturing a semiconductor crystal wafer, which is to cut a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape. The method for manufacturing a semiconductor crystal wafer comprises:

The groove processing step is to form a plurality of grooves surrounding the entire side surface of the aforementioned semiconductor crystal ingot;

The cutting step is to use a wire saw device to make the multiple wires arranged in the multiple grooves formed in the aforementioned groove processing step rotate and move forward simultaneously, thereby cutting the aforementioned semiconductor crystal ingot into sheets;

In the aforementioned groove processing step, the groove processing drum grindstone having a plurality of convex portions corresponding to the aforementioned plurality of concave grooves formed on the side surface and the aforementioned semiconductor crystal ingot are respectively rotated on mutually parallel rotation axes, and the aforementioned groove processing drum grindstone is pressed against the aforementioned semiconductor crystal ingot to form the groove;

In the aforementioned cutting step, before the plurality of lines arranged in the aforementioned plurality of grooves are rotated and advanced simultaneously to cut the aforementioned semiconductor crystal ingot into sheets, a slider having a photographing means provided at the front end side is moved, and the plurality of lines arranged in the plurality of grooves are photographed by the photographing means at a position facing the ingot supporting means supporting the aforementioned semiconductor crystal ingot across the plurality of lines, and the deviation angle of the plurality of lines relative to the plurality of grooves is detected from the photographed image, and the deviation angle is adjusted to zero, and after adjusting the deviation angle, the slider is disassembled.

The method for manufacturing a semiconductor crystal wafer according to the fifth or sixth invention is to perform a groove processing step and a cutting step. The groove processing step is to form grooves corresponding to the plurality of convex portions of the groove processing drum on the side surface of the semiconductor crystal ingot as a whole. The cutting step is to make the plurality of lines arranged in the plurality of grooves formed in the groove processing step rotate and move forward at the same time, thereby cutting the semiconductor crystal ingot into sheets.

Here, for the multiple grooves formed on the entire side surface of the semiconductor crystal ingot by the groove processing drum grindstone, the multiple lines are correctly arranged in the multiple grooves, and the semiconductor crystal ingot can be cut into sheets with good precision along the multiple lines.

In order to correctly arrange the plurality of wires in the plurality of grooves, in the wire saw device, a photographing means for photographing the plurality of wires arranged in the plurality of grooves is provided at a position facing the ingot supporting means for supporting the semiconductor crystal ingot across the plurality of wires, and the deviation angle of the running direction of the plurality of wires relative to the running direction (long side direction) of the plurality of grooves is detected from the photographic image obtained by the photographing means.

Therefore, the deviation angle can be accurately grasped, for example, the support means of the semiconductor crystal ingot can be adjusted, the wire saw axis can be adjusted, etc., to offset the deviation angle. Moreover, after the adjustment, in the fifth invention, the camera means can be retracted by the slider, and in the sixth invention, the slider itself with the camera means at the front end can be disassembled, so that the camera means and the slider will not cause interference in the subsequent steps (for example, the cutting step).

Thus, according to the method for manufacturing a semiconductor crystal wafer of the fifth invention or the sixth invention, a semiconductor crystal ingot can be cut into sheets with good precision, and a high-quality semiconductor crystal wafer can be manufactured simply and reliably.

The seventh invention is a method for manufacturing a semiconductor crystal wafer according to the fifth invention or the sixth invention, wherein in the aforementioned cutting step, before cutting, the aforementioned ingot supporting means first performs a deviation angle adjustment step, so as to rotate and fix the aforementioned semiconductor crystal ingot in such a manner that the deviation angle detected from the photographic image obtained by the aforementioned photographic means becomes zero.

According to the manufacturing method of the semiconductor crystal wafer of the seventh invention, before cutting, the semiconductor crystal ingot can be fixed at a matching position by rotating in a manner that the deviation angle is offset to zero through a deviation angle adjustment step, wherein the deviation angle adjustment step is to rotate the ingot support means around a rotation axis extending perpendicularly to the cutting surface caused by a plurality of lines, and fix the semiconductor crystal ingot at a position where the deviation angle becomes zero.

In this way, the deviation angle of the running direction of the plurality of lines relative to the running direction (long side direction) of the plurality of grooves can be made zero, and the plurality of lines can be correctly arranged in the plurality of grooves.

Thus, according to the method for manufacturing semiconductor crystal wafers of the seventh invention, semiconductor crystal ingots can be cut into sheets with good precision using a simple structure, and high-quality semiconductor crystal wafers can be manufactured simply and reliably.

4: Wire saw device

10: SiC ingot (semiconductor crystal ingot)

11: Grooves

15: Protective plate

20: Groove processing drum grinding stone

21: convex part

30: Grinding pad

31: Gutter

32: Pad convex part

41: Spool

42: Line

43: Crystal tablet support means

44: Photography techniques

45:Framework

46: Connecting plate (assembly and disassembly means)

46 ' : Auxiliary connecting plate

47: Slide

50: Mechanical polishing device (ultra-high synthesis high-precision grinding device)

51: Rotating body

52: Grinding table

53: Diamond grindstone

54: Porous vacuum suction cup (adsorption plate)

100: SiC wafer (semiconductor crystal wafer)

110: One side

120: The other side

STEP100: Groove processing steps

STEP110: Grinding step

STEP120: Cutting step

STEP130: First surface processing step

STEP140: Second side processing step

Z: rotation axis

FIG1 is a flowchart showing the overall process of the manufacturing method of the SiC wafer (semiconductor crystal wafer) of this embodiment.

FIG. 2 is an explanatory diagram showing the SiC wafer manufacturing apparatus of this embodiment, which is composed of the groove processing step and the pad groove forming step in the SiC wafer manufacturing method of FIG. 1 .

FIG3 is an explanatory diagram showing the contents of the groove processing step and the grinding step in the SiC wafer manufacturing method of FIG1.

FIG. 4 is an explanatory diagram showing the contents of the cutting step in the SiC wafer manufacturing method of FIG. 1 .

FIG. 5 is an explanatory diagram showing the deviation angle adjustment in the cutting step of the SiC wafer manufacturing method of FIG. 1 .

FIG6 is an explanatory diagram showing the contents of the first surface processing step and the second surface processing step in the manufacturing method of the SiC wafer in FIG1.

As shown in FIG1 , in this embodiment, the method for manufacturing a SiC wafer of a semiconductor crystal wafer is used to obtain a sheet-shaped SiC wafer cut from a SiC ingot ground into a cylindrical shape. The manufacturing method includes: a groove processing step (STEP100/FIG1 ), a grinding step (STEP110/FIG1 ), a cutting step (STEP120/FIG1 ), a first surface processing step (STEP130/FIG1 ), and a second surface processing step (STEP140/FIG1 ).

Referring to Figures 2 to 6, the details of each step and the SiC wafer manufacturing device of this embodiment are described.

The groove processing drum grinding stone 20 used in the groove processing step (STEP100/Figure 1) shown in Figure 2 is commonly used for the pre-performed pad groove forming processing.

The groove processing drum grindstone 20 is a drum grindstone used to form a plurality of grooves 11 surrounding the entire side surface of the SiC ingot 10, and a plurality of convex portions 21 corresponding to the plurality of grooves 11 are formed on the side surface.

First, the pad groove forming process is a process for the cylindrical grinding pad 30 used to grind out a plurality of grooves 11. The grinding pad 30 and the groove processing drum grindstone 20 are rotated on mutually parallel rotation axes, and the groove processing drum grindstone 20 is pressed against the grinding pad 30, thereby forming a plurality of pad grooves 31 corresponding to the plurality of convex portions 21 on the side surface of the grinding pad 30 as a whole.

At this time, the polishing pad 30 (which contains appropriate moisture as needed) forms the pad groove 31 in a frozen and solidified state. And, the polishing pad 30 with the pad groove 31 is thawed (dried as needed) and used in the following steps.

Next, in the groove processing step (STEP 100/Figure 1), a plurality of grooves 11 surrounding the entire side surface of the SiC ingot 10 are formed by a common groove processing drum grindstone 20.

Specifically, in the groove processing step (STEP100/Figure 1), the groove processing drum grindstone 20 and the SiC crystal ingot 10 are respectively rotated on mutually parallel rotation axes while the groove processing drum grindstone 20 is pressed against the SiC crystal ingot 10, thereby forming the grooves 11.

At this time, the SiC crystal ingot 10 is supported to be freely rotatable while its two end faces are protected by a pair of protective plates 15, 15.

The protective plate 15 is a synthetic resin such as polyvinyl chloride, and can be bonded to the SiC crystal ingot 10 by adhesives as needed.

The pair of protective plates 15, 15 can protect the two ends of the SiC ingot 10, and prevent chipping and cracking of the two ends. Therefore, multiple grooves 11 can be formed close to the edge of the two end faces, and more can be cut to obtain more SiC wafers 100 described later.

In addition, when the SiC ingot 10 is clamped and fixed on the rotating shaft, the protective plates 15, 15 can be processed (such as drilling holes) as needed before being fixed. Moreover, even so, since the SiC ingot 10 itself is not processed, it will not be damaged.

The multiple grooves 11 of the SiC ingot 10 and the multiple grooves 31 of the polishing pad 30 formed by the above processing steps have the same shape (same spacing) corresponding to the multiple convex parts 21 of the groove processing drum grindstone 20.

Therefore, as shown in FIG3 , it is possible to form a plurality of grooves 11 in the SiC ingot 10 in the groove processing step (STEP100/FIG1) substantially simultaneously, and in the grinding step (STEP110/FIG1), grind along the groove 11 by using a plurality of pad protrusions 32 (the protrusions between two adjacent pad grooves 31, 31) of the grinding pad 30 having the same spacing as the groove 11.

Here, the polishing step (STEP 110/Figure 1) can be performed by polishing with CMP slurry (chemical mechanical liquid abrasive), but powder abrasive (polishing abrasive) can also be added to the surface of the polishing pad 30 intermittently or continuously.

Furthermore, as shown in FIG. 4(A), in the cutting step (STEP 120/FIG. 1), a plurality of wires 42 spanning between the wire axes 41, 41 of the wire saw device 4 of the cutting processing device are arranged in the plurality of grooves 11 formed in the groove processing step (STEP 100/FIG. 1), so that the wires 42 are rotated and moved forward at the same time, thereby cutting the SiC ingot 10 into sheets.

At this time, the plurality of lines 42 can be correctly arranged in the plurality of grooves 11, and the SiC ingot 10 can be cut into sheets with good precision in a single operation.

In this regard, in the present embodiment, the wire saw device 4 is provided with an imaging device 44. The imaging device 44 is disposed at a position facing the ingot support device 43 supporting the SiC ingot 10 across the plurality of wires 42, and images the plurality of wires 42 arranged in the plurality of grooves 11.

The ingot support means 43 supports the SiC ingot 10, and its base is formed by, for example, a turntable, which can rotate in the direction of the arrow with the rotation axis Z extending vertically relative to the cut surface caused by the plurality of lines 42 (extending in the lead vertical direction in the figure) as the center and can be fixed at any position, thus having the function of a deviation angle adjustment means.

The imaging means 44 is constituted by, for example, a CCD camera, and as shown in FIG. 4(B), is connected to the frame 45 of the wire saw device 4 via a hollow frame-shaped connecting plate 46, and is disposed at the front end side of a slider 47 in a hollow frame that is configured to freely move forward and backward in the connecting plate 46 (to be precise, the connecting plate 46 and an auxiliary connecting plate 46 ' integrally formed with the connecting plate 46), so as to photograph the plurality of lines 42 overlapping the plurality of grooves 11.

Here, the slider 47 can be an electric slider or a manual slider that is manually slidable, and can be detachably mounted on the frame 45 of the wire saw device 4 via a connecting plate 46 (equivalent to the mounting and disassembly means of the present invention). In addition, in this embodiment, the connecting plate 46 is detachably fixed by being fastened to the frame 45 with screws, but the detachably fixed means is not limited to this.

In addition, in this embodiment, an electric pan-tilt head (up and down pan-tilt head) for focusing and zooming adjustment is provided between the camera means 44 and the slider 47, but the electric pan-tilt head can also be omitted.

In the cutting step (STEP120/Figure 1) performed by the wire saw device 4 constructed in this way, the deviation angle adjustment step is first performed before cutting.

In the deviation angle adjustment step, first move the front end side of the slider 47 so that the imaging direction of the imaging means 44 is configured at a imaging position where a plurality of grooves 11 and a plurality of lines 42 overlap (configured to photograph from directly below the SiC crystal ingot 10 in the figure to directly above).

In this state, a photographic image taken by the photographic means 44 is obtained, and the deviation angles of the plurality of lines relative to the plurality of grooves 11 are detected from the photographic image.

At this time, the camera means 44 can be slid by the slider 47 to continuously shoot images. Thus, even if a single shot cannot capture all the lines 42 of the multiple grooves 11 in the image, the deviation angles of all the lines 42 relative to the multiple grooves 11 can be detected by scanning and continuously shooting.

Specifically, as shown in the actual photographic image of FIG5 , the deviation angle (whether they are parallel) between the direction of travel of the groove (left-right direction in the figure) and the direction of travel of line 42 (left-right direction in the figure) can be detected.

The detection of the deviation angle can be performed by visual observation, but for example, the photographic image can also be binarized and edge detection processing can be performed, and the direction of the width position (upper and lower positions) of the groove 11 and the direction of the width position (upper and lower positions) of the line 42 can be detected as straight lines, and the deviation angle can be detected by the inclination of these straight lines through image processing.

Next, the ingot support means 43 is rotated around the rotation axis Z to offset the detected deviation angle to zero. After confirming that the deviation angle is zero in the photographic image, the SiC ingot 10 is fixed in its position.

Here, the deviation angle adjustment means is constituted by an electric turntable. If it is a structure that can be automatically adjusted according to the photographed image, it can also be constituted so that the deviation corresponding to the inclination between the above-mentioned straight lines is used as feedback control of the output step number of the stepping motor output of the turntable.

When the deviation angle is adjusted, the front end of the slider 47 is moved back and away. Then, the slider 47 itself is removed from the frame 45 of the wire saw device 4 via the connecting plate 46, so that the slider 47 and the camera 44 will not cause any hindrance or damage in the subsequent cutting steps.

In this way, the plurality of lines 42 can be correctly arranged in the plurality of grooves 11, and the SiC ingot 10 can be cut into sheets with good precision in a single operation.

Furthermore, as shown in FIG5 , since the periphery of the SiC wafer 100 obtained by cutting into slices is uniformly chamfered at the corners by the polishing pad 30 with the correct spacing set to be consistent, no chamfering process is required after cutting.

Here, regarding the structure of the semiconductor crystal wafer (SiC wafer) manufacturing device (cutting device) of this embodiment, it can be composed of the above-mentioned groove processing drum grindstone 20, grinding pad 30 and wire saw device 4.

Next, as shown in FIG6 , in the first surface processing step (STEP130/FIG1 ), one surface 110 on either side of the cut surface is used as a support surface, and the other surface 120 is subjected to mechanical polishing (high-precision grinding).

Specifically, in the first surface processing step (STEP 130/Figure 1), grinding is performed by a mechanical polishing device 50 (ultra-high synthetic high-precision grinding device) that applies mechanical polishing.

The mechanical polishing device 50 comprises a rotating body 51 and a diamond grindstone 53 located on a flat grinding table 52.

First, one surface 110 is used as the upper surface, and it is supported by the porous vacuum suction cup 54 of the suction plate of the rotating body 51, and the other surface 120 is used as the lower surface, and the other surface 120 is ground by the diamond grindstone 53.

At this time, the rotating body 51 and the diamond grindstone 53 are rotationally driven by a driving device not shown in the figure, and the rotating body 51 is pressed against the diamond grindstone 53 by an air compressor not shown in the figure to perform grinding on the other side 120.

Here, the diamond grindstone 53 can be dressed by a dresser after the grinding process.

Furthermore, the mechanical polishing device 50 may have a functional water supply pipe as needed so that multiple types of functional water can be used during processing.

Next, in the second surface processing step (STEP 140/Figure 1), the other surface 120 that has been subjected to high-precision grinding in the first surface processing step is used as the upper surface, and the same high-precision grinding as in the first surface processing step is performed on the one surface 110.

That is, the other surface 120 is used as the upper surface, and is adsorbed on the porous vacuum suction cup 54 of the adsorption plate of the rotating body 51, and the one surface 110 is used as the lower surface, and the one surface 110 is ground by the diamond grindstone 53.

At this time, the trimmer can be pushed onto the diamond grindstone 53 for trimming as needed.

According to the mechanical polishing (high-precision grinding) treatment performed in the first surface processing step (STEP130/Figure 1) and the second surface processing step (STEP140/Figure 1), one side and the other side of the non-transfer cut surface with high flatness obtained by the cutting step are sequentially used as the support surface (adsorption surface) and the other side is subjected to mechanical polishing (high-precision grinding). In this way, the so-called transfer can be prevented to obtain a high-quality SiC wafer, and the conventional free grindstone processing step can be greatly simplified, that is, the complex manufacturing steps such as multiple polishing from one to four times can be greatly simplified.

More specifically, there is no need to exchange grinding stones for rough grinding and multiple times of fine grinding. For example, a grinding process can be directly performed once with a grinding stone of #30000 or above to proceed to fine grinding. Therefore, it is not only simple, but also has the advantage of being able to largely ensure the usable genuine semiconductor layer from the SiC wafer 100.

Here, in the high-precision grinding process of the first surface processing step (STEP130/Figure 1) and the second surface processing step (STEP140/Figure 1), the size of the SiC wafer 100 is currently limited to 8 inches, but wafers of various diameters (up to 12 inches) can be set according to the area of the grinding head for high-precision grinding processing.

The above description is the details of the manufacturing method of the SiC wafer of this embodiment. As described in detail above, according to the manufacturing method and device of the SiC wafer of this embodiment, for the plurality of grooves 11 formed on the entire side surface of the SiC ingot 10 by the groove processing drum grindstone 20, the plurality of wires 42 can be correctly arranged on the plurality of grooves 11, and the grooves 11 become guides during cutting. The wires 42 will not be biased against a single side surface of the groove 11 (for example, a side surface in the width direction), so that the cutting part of the wire is concentrated at the bottom of the groove 11, and the SiC ingot 10 can be cut into sheets with good precision by a single operation of the plurality of wires 42.

In addition, in the above-mentioned embodiment, the groove forming process can also be changed to make the groove 31 and the convex portion 32 have the same shape as the multiple grooves 11 (the multiple convex portions 21 of the groove processing drum grindstone 20) surrounding the entire side surface of the SiC crystal ingot 10.

Specifically, in the pad groove forming process, a cylindrical pad groove processing grindstone is prepared in advance, and the groove processing drum grindstone 20 and the pad groove processing grindstone are rotated on mutually parallel rotation axes, and the groove processing drum grindstone 20 is pressed against the pad groove processing grindstone, thereby forming pad processing grooves (pad processing convex parts) corresponding to the plurality of convex parts 21 on the pad groove processing grindstone, and then, the pad groove processing grindstone and the grinding pad 30 are rotated on mutually parallel rotation axes, and the pad groove processing grindstone is pressed against the grinding pad 30, thereby forming a plurality of pad grooves corresponding to the pad processing grooves (pad processing convex parts) on the side surface of the grinding pad 30 as a whole.

In addition, in the SiC wafer manufacturing method of this embodiment, after the above series of treatments, a chemical mechanical polishing (CMP) step, a wafer cleaning step, etc. can be performed as needed.

Furthermore, this embodiment illustrates the method of manufacturing semiconductor crystal wafers by manufacturing SiC wafers from SiC ingots, but semiconductor crystals are not limited to SiC, and can also be gallium arsenide, indium phosphide, silicon, and other compound semiconductors.

In addition, this embodiment describes the situation in which the SiC crystal ingot 10 is supported to be freely rotatable while its two end faces are protected by a pair of protective plates 15, 15 in the groove processing step (STEP100/Figure 1), but it is not limited to this. For example, the pair of protective plates 15, 15 can be omitted and the SiC crystal ingot 10 can be directly fixed to the rotating shaft.

Furthermore, in steps other than the groove processing step (STEP100/FIG. 1), such as the grinding step (STEP110/FIG. 1) and the cutting step (STEP120/FIG. 1), the processing can also be performed while the two end faces of the SiC ingot 10 are protected by a pair of protective plates 15, 15.

Furthermore, this embodiment is as shown in FIG. 4 , and the positional relationship between the wire saw device 4 and the SiC ingot 10 is described by placing the SiC ingot 10 on the outer side of the rotating wire 42 and (relatively) making the wire 42 move outward in the circumferential direction (upper side in the figure), but it is not limited to this.

For example, the SiC ingot 10 may be arranged inside the rotating wire 42 and the wire 42 may be moved inward in the circumferential direction (toward the lower side in the figure). In this case, the imaging means 44 is arranged above the wire 42 (arranged to photograph from directly above to directly below the SiC ingot 10).

STEP100: Groove processing steps

STEP110: Grinding step

STEP120: Cutting step

STEP130: First surface processing step

STEP140: Second side processing step

Claims (7)

A semiconductor crystal wafer manufacturing device is used to cut a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape. The semiconductor crystal wafer manufacturing device is equipped with: The groove processing drum grindstone is used to form a plurality of grooves surrounding the entire side surface of the aforementioned semiconductor crystal ingot, and a plurality of convex portions corresponding to the plurality of grooves are formed on the side surface; The wire saw device causes the plurality of wires arranged in the plurality of grooves to rotate and move forward simultaneously, thereby cutting the semiconductor crystal ingot into sheets; The imaging means is to photograph the plurality of lines arranged in the plurality of grooves at a position facing the ingot supporting means supporting the semiconductor crystal ingot across the plurality of lines in the wire saw device; and The slide is provided with the aforementioned photographing means at the front end side, which can make the photographing means move from the frame of the aforementioned wire saw device toward the aforementioned position for photographing, and retreat after photographing; wherein, Detect the deviation angles of the aforementioned plurality of lines relative to the aforementioned plurality of grooves from the photographic image obtained by the aforementioned photographic means. A semiconductor crystal wafer manufacturing device is used to cut a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape. The semiconductor crystal wafer manufacturing device is equipped with: The groove processing drum grindstone is used to form a plurality of grooves surrounding the entire side surface of the aforementioned semiconductor crystal ingot, and a plurality of convex portions corresponding to the plurality of grooves are formed on the side surface; The wire saw device causes the plurality of wires arranged in the plurality of grooves to rotate and move forward simultaneously, thereby cutting the semiconductor crystal ingot into sheets; The imaging means is to photograph the plurality of lines arranged in the plurality of grooves in the wire saw device at a position facing the ingot supporting means supporting the semiconductor crystal ingot across the plurality of lines; The slider is provided with the aforementioned photographing means at the front end side, and can make the photographing means move toward the aforementioned position for photographing; and The installation and disassembly means can freely install and disassemble the aforementioned sliding member on the aforementioned wire saw device; wherein, Detect the deviation angles of the aforementioned plurality of lines relative to the aforementioned plurality of grooves from the photographic image obtained by the aforementioned photographic means. A semiconductor crystal wafer manufacturing device as described in claim 1 or 2, wherein: The slider slides the camera means at the position to continuously photograph the plurality of lines arranged in the plurality of grooves. A semiconductor crystal wafer manufacturing device as described in claim 1 or 2, wherein: The aforementioned ingot supporting means has a deviation angle adjusting means, and the deviation angle adjusting means is used to rotate and fix the aforementioned semiconductor crystal ingot in such a manner that the deviation angle detected from the photographic image obtained by the aforementioned photographic means becomes zero. A method for manufacturing a semiconductor crystal wafer is to cut a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape. The method for manufacturing a semiconductor crystal wafer comprises: The groove processing step is to form a plurality of grooves surrounding the entire side surface of the aforementioned semiconductor crystal ingot; and The cutting step is to use a wire saw device to make the multiple wires arranged in the multiple grooves formed in the aforementioned groove processing step rotate and move forward simultaneously, thereby cutting the aforementioned semiconductor crystal ingot into sheets; In the aforementioned groove processing step, the groove processing drum grindstone having a plurality of convex portions corresponding to the aforementioned plurality of concave grooves formed on the side surface and the aforementioned semiconductor crystal ingot are respectively rotated on mutually parallel rotation axes, and the aforementioned groove processing drum grindstone is pressed against the aforementioned semiconductor crystal ingot to form the groove; In the aforementioned cutting step, before the plurality of wires arranged in the plurality of grooves are rotated and simultaneously advanced to cut the aforementioned semiconductor crystal ingot into sheets, a slider having a camera means provided at the front end side is moved from the frame of the aforementioned wire saw device, and the plurality of wires arranged in the plurality of grooves are photographed by the camera means at a position facing the ingot support means supporting the aforementioned semiconductor crystal ingot across the plurality of wires, and the deviation angle of the plurality of wires relative to the plurality of grooves is detected from the photographed image, and the deviation angle is adjusted to zero, and after adjusting the deviation angle, the aforementioned slider is retreated to avoid the deviation angle. A method for manufacturing a semiconductor crystal wafer is to cut a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape. The method for manufacturing a semiconductor crystal wafer comprises: The groove processing step is to form a plurality of grooves surrounding the entire side surface of the aforementioned semiconductor crystal ingot; and The cutting step is to use a wire saw device to make the multiple wires arranged in the multiple grooves formed in the aforementioned groove processing step rotate and move forward simultaneously, thereby cutting the aforementioned semiconductor crystal ingot into sheets; In the aforementioned groove processing step, the groove processing drum grindstone having a plurality of convex portions corresponding to the aforementioned plurality of concave grooves formed on the side surface and the aforementioned semiconductor crystal ingot are respectively rotated on mutually parallel rotation axes, and the aforementioned groove processing drum grindstone is pressed against the aforementioned semiconductor crystal ingot to form the groove; In the aforementioned cutting step, before the plurality of lines arranged in the aforementioned plurality of grooves are rotated and advanced simultaneously to cut the aforementioned semiconductor crystal ingot into sheets, a slider having a photographing means provided at the front end side is moved forward, and the plurality of lines arranged in the plurality of grooves are photographed by the photographing means at a position facing the ingot supporting means supporting the aforementioned semiconductor crystal ingot across the plurality of lines, and the deviation angle of the plurality of lines relative to the plurality of grooves is detected from the photographed image, and the deviation angle is adjusted to zero, and after adjusting the deviation angle, the slider is disassembled. A method for manufacturing a semiconductor crystal wafer as described in claim 5 or 6, wherein: In the aforementioned cutting step, before cutting, the aforementioned ingot supporting means first performs a deviation angle adjustment step, so as to rotate and fix the aforementioned semiconductor crystal ingot in such a way that the deviation angle detected from the photographic image obtained by the aforementioned photographic means becomes zero.

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