Apparatus and method for manufacturing semiconductor crystal wafer

Abstract

The purpose of the present invention is to provide an apparatus and a method for manufacturing a semiconductor crystal wafer, whereby a high-quality semiconductor crystal wafer can be easily and reliably manufactured. This SiC wafer manufacturing method for a semiconductor crystal wafer is provided with a trench processing step (STEP100 / fig. 1), a polishing step (STEP110 / fig. 1), a cutting step (STEP120 / fig. 1), a first surface processing step (STEP130 / fig. 1), and a second surface processing step (STEP140 / fig. 1). In the cutting step, a plurality of wires (42) disposed in a plurality of recesses (11) are imaged by an imaging device (44) provided at a position facing an ingot support device (43) that supports the SiC ingot (10) across the plurality of wires (42) before the SiC ingot (10) is cut into a sheet shape by advancing the plurality of wires (42) disposed in the plurality of recesses (11) while being wound. A deviation angle of the plurality of lines 42 with respect to the plurality of grooves 11 is detected from a captured image obtained by the imaging device 44, and the deviation angle is adjusted to zero.

Description

Technical Field

[0001] The present invention relates to a semiconductor crystal wafer manufacturing apparatus and a manufacturing method for cutting out sheet-shaped wafers from a semiconductor crystal ingot ground into a cylindrical shape. Background Art

[0002] In the past, as for the manufacturing method of SiC wafers belonging to this type of semiconductor crystal wafer, as shown in the following patent document 1, there is a known method for manufacturing SiC wafers, which includes a wafer shape forming step, a subsequent process-degraded layer removal step, and a final mirror polishing step. As for the wafer shape forming step, for example, it includes: a crystal ingot forming step, processing a single crystal SiC block grown by crystallization into a cylindrical crystal ingot; a crystal orientation forming step, forming a notch in a part of the outer periphery of the crystal ingot to become a mark showing the crystal orientation of the crystal ingot; a slicing step, slicing the single crystal SiC crystal ingot and processing it into 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-degraded layer removal step, for example, the process-degraded layer formed in the SiC wafer in the previous step is removed. The mirror polishing step is, for example, a chemical mechanical polishing (CMP) step in which polishing is performed using both the mechanical action of a polishing pad and the chemical action of a slurry.

[0003] (Prior art literature)

[0004] (Patent Document)

[0005] Patent document 1: Japanese Patent Application Publication No. 2020-15646. Summary of the invention

[0006] [Problems to be solved by the invention]

[0007] However, the above-mentioned conventional SiC wafer manufacturing method has problems such as multiple and complicated processes, complex device structure and high manufacturing cost.

[0008] On the other hand, if the manufacturing process is simplified, it will be difficult to stably obtain the required quality of SiC wafers.

[0009] In view of this, an object of the present invention is to provide a semiconductor crystal wafer manufacturing apparatus and a manufacturing method that can easily and reliably manufacture high-quality semiconductor crystal wafers.

[0010] [Methods to solve the problem]

[0011] The semiconductor crystal wafer manufacturing apparatus of the first invention cuts out a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape, and the semiconductor crystal wafer manufacturing apparatus comprises:

[0012] A groove processing drum grindstone is a drum grindstone for forming 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;

[0013] A wire saw device that causes a plurality of wires disposed in the plurality of grooves to rotate and advance simultaneously, thereby cutting the semiconductor crystal ingot into sheets;

[0014] an imaging device for imaging the plurality of wires arranged in the plurality of grooves at a position facing an ingot supporting device supporting the semiconductor crystal ingot across the plurality of wires in the wire saw device; and

[0015] The slide has the camera device disposed at the front end thereof, so that the camera device can move from the frame of the wire saw device toward the position for taking pictures, and retreat after taking pictures; wherein,

[0016] The deviation angles of the plurality of lines relative to the plurality of grooves are detected from the image captured by the image capturing device.

[0017] The semiconductor crystal wafer manufacturing apparatus of the second invention cuts out a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape, and the semiconductor crystal wafer manufacturing apparatus comprises:

[0018] A groove processing drum grindstone is a drum grindstone for forming 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;

[0019] A wire saw device that causes a plurality of wires disposed in the plurality of grooves to rotate and advance simultaneously, thereby cutting the semiconductor crystal ingot into sheets;

[0020] An imaging device for imaging the plurality of wires arranged in the plurality of grooves at a position facing an ingot support device supporting the semiconductor crystal ingot across the plurality of wires in the wire saw device;

[0021] A slider having the aforementioned camera device disposed at the front end thereof, and capable of moving the camera device toward the aforementioned position for performing camera imaging; and

[0022] The mounting and dismounting device can be used to mount the sliding member on the wire saw device in a freely mountable and dismountable manner; wherein,

[0023] The deviation angles of the plurality of lines relative to the plurality of grooves are detected from the image captured by the image capturing device.

[0024] The manufacturing device of the semiconductor crystal wafer according to the first invention or the second invention is composed of a groove processing drum wheel grindstone and an additional component corresponding to the groove processing drum wheel grindstone. The groove processing drum wheel grindstone is a drum wheel grindstone 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.

[0025] The first additional component is a wire saw device that winds a plurality of wires arranged on a plurality of grooves formed on the entire side surface of the semiconductor crystal ingot.

[0026] The second additional component is a camera device, which is provided in the wire saw device at a position facing the ingot support device that supports the semiconductor crystal ingot across the plurality of wires, and takes images of the plurality of wires arranged in the plurality of grooves. The camera device is provided with a slider that moves the camera device toward the position where the image is taken. In addition, the second invention is provided with a mounting and dismounting device that can mount and dismount the slider on the wire saw device freely.

[0027] In the above configuration, the plurality of lines are accurately arranged in the plurality of grooves formed on the entire side surface of the semiconductor crystal ingot by the groove processing drum grindstone, and the semiconductor crystal ingot can be cut into sheets with high accuracy along the plurality of lines.

[0028] Here, in order to accurately arrange the plurality of lines on the plurality of grooves, the deviation angle of the running direction of the plurality of lines with respect to the running direction (longitudinal direction) of the plurality of grooves is detected from the captured image obtained by the imaging device.

[0029] Therefore, the deviation angle can be accurately grasped, and for example, the semiconductor crystal ingot support device and the wire saw wire axis can be adjusted to offset the deviation angle. Moreover, after the adjustment, in the first invention, the camera device can be retracted by the slide, and in the second invention, the slide itself with the camera device at the front end can be removed so that the camera device and the slide will not cause interference in the subsequent steps (for example, the cutting step).

[0030] As described above, according to the semiconductor crystal wafer manufacturing apparatus of the first invention or the second invention, a semiconductor crystal ingot can be cut into slices with high accuracy, and high-quality semiconductor crystal wafers can be manufactured simply and reliably.

[0031] A semiconductor crystal wafer manufacturing apparatus according to a third invention is the first invention or the second invention, wherein the slider slides the imaging device at the position, and the imaging device continuously photographs the plurality of lines arranged in the plurality of grooves.

[0032] According to the semiconductor crystal wafer manufacturing device of the third invention, the camera device is slid by a slider. Even if a single shot cannot capture all the multiple lines of the multiple grooves in the camera image, the deviation angles of all the multiple lines relative to the multiple grooves can be detected and adjusted by scanning and continuously photographing.

[0033] As described above, according to the semiconductor crystal wafer manufacturing apparatus of the third invention, a semiconductor crystal ingot can be cut into slices with higher accuracy, and high-quality semiconductor crystal wafers can be manufactured simply and reliably.

[0034] The semiconductor crystal wafer manufacturing device of the fourth invention is that in the first invention or the second invention, the above-mentioned ingot supporting device has a deviation angle adjustment device, which rotates and fixes the above-mentioned semiconductor crystal ingot in such a way that the deviation angle detected from the camera image obtained by the above-mentioned camera device becomes zero.

[0035] According to the manufacturing device of the semiconductor crystal wafer of the fourth invention, a deviation angle adjustment device is constructed in the ingot supporting device, and the semiconductor crystal ingot is fixed at a position where the deviation angle becomes zero by rotating around a rotation axis extending perpendicularly to the cut surface caused by multiple lines, so that the semiconductor crystal ingot is fixed at a matching position.

[0036] According to this, the deviation angle of the running direction of the plurality of lines with respect to the running direction (longitudinal direction) of the plurality of grooves becomes zero, and the plurality of lines can be accurately arranged in the plurality of grooves.

[0037] As described above, according to the semiconductor crystal wafer manufacturing apparatus of the fourth invention, a semiconductor crystal ingot can be cut into slices with high accuracy with a simple structure, and high-quality semiconductor crystal wafers can be manufactured simply and reliably.

[0038] A method for manufacturing a semiconductor crystal wafer according to a fifth invention is to cut a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape, the method comprising:

[0039] a groove processing step of forming a plurality of grooves surrounding the entire side surface of the semiconductor crystal ingot; and

[0040] a cutting step of cutting the semiconductor crystal ingot into sheets by rotating and advancing a plurality of wires arranged on the plurality of grooves formed in the groove processing step by a wire saw device;

[0041] In the groove processing step, the groove processing drum grindstone having a plurality of convex portions corresponding to the plurality of concave grooves formed on the side surface and the semiconductor crystal ingot are respectively rotated on mutually parallel rotation axes, and the groove processing drum grindstone is pressed against the semiconductor crystal ingot, thereby forming the concave grooves;

[0042] In the aforementioned cutting step, before causing the plurality of wires arranged in the aforementioned plurality of grooves to rotate and advance simultaneously to cut the aforementioned semiconductor crystal ingot into sheets, a slide having a camera device provided on its front end side is caused to move from the frame of the aforementioned wire saw device, and at a position facing an ingot supporting device supporting the aforementioned semiconductor crystal ingot across the plurality of wires, the plurality of wires arranged in the plurality of grooves are photographed by the camera device, and deviation angles of the plurality of wires relative to the plurality of grooves are detected from the photographed images, and the deviation angles are adjusted to zero, and after adjusting the deviation angles, the aforementioned slide is retreated to avoid the deviation angles.

[0043] A method for manufacturing a semiconductor crystal wafer according to a sixth aspect of the present invention is to cut a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape, the method comprising:

[0044] A groove processing step of forming a plurality of grooves surrounding the entire side surface of the semiconductor crystal ingot;

[0045] a cutting step of cutting the semiconductor crystal ingot into sheets by rotating and advancing a plurality of wires arranged on the plurality of grooves formed in the groove processing step by a wire saw device;

[0046] In the groove processing step, the groove processing drum grindstone having a plurality of convex portions corresponding to the plurality of concave grooves formed on the side surface and the semiconductor crystal ingot are respectively rotated on mutually parallel rotation axes, and the groove processing drum grindstone is pressed against the semiconductor crystal ingot, thereby forming the concave grooves;

[0047] In the aforementioned cutting step, before causing the plurality of wires arranged in the aforementioned plurality of grooves to rotate and advance simultaneously to cut the aforementioned semiconductor crystal ingot into sheets, a slide having a camera device provided on its front end side is moved forward, and at a position facing an ingot supporting device supporting the aforementioned semiconductor crystal ingot across the plurality of wires, the plurality of wires arranged in the plurality of grooves are photographed by the camera device, and deviation angles of the plurality of wires relative to the plurality of grooves are detected from the photographed images, and the deviation angles are adjusted to zero, and after adjusting the deviation angles, the slide is removed.

[0048] According to the manufacturing method of the semiconductor crystal wafer of the fifth invention or the sixth invention, a groove processing step and a cutting step are performed. The groove processing step forms concave grooves corresponding to the multiple convex portions of the groove processing drum wheel on the side surface of the semiconductor crystal ingot as a whole. The cutting step causes the multiple lines arranged in the multiple concave grooves formed in the groove processing step to rotate and advance simultaneously, thereby cutting the aforementioned semiconductor crystal ingot into sheets.

[0049] Here, with respect to the plurality of grooves formed on the entire side surface of the semiconductor crystal ingot by the groove processing drum grindstone, the plurality of lines are accurately arranged in the plurality of grooves, and the semiconductor crystal ingot can be cut into sheets with high accuracy along the plurality of lines.

[0050] In order to correctly arrange the multiple wires in the multiple grooves, in the wire saw device, a camera device for photographing the multiple wires arranged in the multiple grooves is provided at a position opposite to the ingot supporting device supporting the semiconductor crystal ingot across the multiple wires, and the deviation angle of the moving direction of the multiple wires relative to the moving direction (long side direction) of the multiple grooves is detected from the camera image obtained by the camera device.

[0051] Therefore, the deviation angle can be accurately grasped, and for example, the semiconductor crystal ingot support device and the wire saw wire axis can be adjusted to offset the deviation angle. Moreover, after the adjustment, in the fifth invention, the camera device can be retracted by the slide, and in the sixth invention, the slide itself with the camera device at the front end can be removed so that the camera device and the slide will not cause interference in the subsequent steps (for example, the cutting step).

[0052] As described above, according to the method for manufacturing a semiconductor crystal wafer of the fifth or sixth invention, a semiconductor crystal ingot can be cut into slices with high accuracy, and a high-quality semiconductor crystal wafer can be manufactured simply and reliably.

[0053] In the seventh invention of the semiconductor crystal wafer manufacturing method of the fifth invention or the sixth invention, in the aforementioned cutting step, before cutting, the aforementioned ingot supporting device first performs a deviation angle adjustment step to rotate and fix the aforementioned semiconductor crystal ingot in such a manner that the deviation angle detected from the camera image obtained by the aforementioned camera device becomes zero.

[0054] According to the manufacturing method of the semiconductor crystal wafer of the seventh invention, before cutting, a deviation angle adjustment step can be performed to rotate the semiconductor crystal ingot in a manner that the deviation angle is offset to zero, and the semiconductor crystal ingot can be fixed at a matching position, wherein the deviation angle adjustment step is performed in an ingot support device, rotating the ingot around a rotation axis extending perpendicularly to a cut surface caused by a plurality of lines, and fixing the semiconductor crystal ingot at a position where the deviation angle becomes zero.

[0055] According to this, the deviation angle of the running direction of the plurality of lines with respect to the running direction (longitudinal direction) of the plurality of grooves can be made zero, and the plurality of lines can be accurately arranged in the plurality of grooves.

[0056] As described above, according to the method for manufacturing a semiconductor crystal wafer of the seventh invention, a semiconductor crystal ingot can be cut into slices with high accuracy with a simple structure, and a high-quality semiconductor crystal wafer can be manufactured simply and reliably. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 It is a flowchart showing the entire process of the method for manufacturing a SiC wafer (semiconductor crystal wafer) according to the present embodiment.

[0058] Figure 2 Is displayed based on Figure 1 An explanatory diagram of the SiC wafer manufacturing apparatus of the present embodiment, which is composed of a groove processing step and a pad groove forming step in the SiC wafer manufacturing method.

[0059] Figure 3 Yes Display Figure 1 An explanatory diagram of the contents of the groove processing step and the polishing step in the method for manufacturing a SiC wafer.

[0060] Figure 4 shows Figure 1 An explanatory diagram of the contents of the cutting step in the method for manufacturing a SiC wafer.

[0061] Figure 5 Yes Display Figure 1 An explanatory diagram of adjustment of the deviation angle in the cutting step of the SiC wafer manufacturing method.

[0062] Figure 6 Yes Display Figure 1 An explanatory diagram of the contents of the first surface processing step and the second surface processing step in the method for manufacturing a SiC wafer. DETAILED DESCRIPTION

[0063] like Figure 1 As shown, 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 crystal ingot ground into a cylindrical shape. This manufacturing method includes: a groove processing step (STEP100 / Figure 1 )、Grinding step (STEP110 / Figure 1 )、Cut step (STEP120 / Figure 1 )、First surface processing step (STEP130 / Figure 1 ) and the second side processing step (STEP140 / Figure 1 ).

[0064] Reference Figures 2 to 6, describing the details of each step and the SiC wafer manufacturing apparatus of this embodiment.

[0065] Will Figure 2 The groove processing steps shown (STEP100 / Figure 1 The groove processing drum grindstone 20 used in the above process is commonly used for the pad groove forming process performed in advance.

[0066] The groove processing drum grindstone 20 is a drum grindstone for forming a plurality of concave grooves 11 surrounding the entire side surface of the SiC ingot 10 , and a plurality of convex portions 21 corresponding to the plurality of concave grooves 11 are formed on the side surface.

[0067] First, in the pad groove forming process, a cylindrical grinding pad 30 for grinding a plurality of grooves 11 is processed. The grinding pad 30 and the groove processing drum wheel grindstone 20 are rotated on rotating axes parallel to each other, and the groove processing drum wheel grindstone 20 is pressed against the grinding pad 30, thereby forming a plurality of pad grooves 31 corresponding to the plurality of protrusions 21 on the side surface of the grinding pad 30 as a whole.

[0068] At this time, the polishing pad 30 (containing appropriate water as needed) is frozen and solidified to form the pad groove 31. The polishing pad 30 with the pad groove 31 is thawed (dried as needed) and then used in the following steps.

[0069] Next, the groove processing step (STEP100 / Figure 1 ) in which a plurality of concave grooves 11 surrounding the entire side surface of the SiC ingot 10 are formed by a common groove processing drum grindstone 20.

[0070] Specifically, the groove processing step (STEP100 / Figure 1 ), a groove processing drum wheel grindstone 20 having a plurality of convex portions 21 corresponding to the plurality of concave grooves 11 formed on the entire side and a SiC crystal ingot 10 are respectively rotated on mutually parallel rotation axes, and the groove processing drum wheel grindstone 20 is pressed against the SiC crystal ingot 10, thereby forming the concave grooves 11.

[0071] At this time, SiC ingot 10 is rotatably supported while both end surfaces thereof are protected by a pair of protection plates 15 , 15 .

[0072] The protection plate 15 is made of a synthetic resin such as polyvinyl chloride, and can be bonded to the SiC ingot 10 by an adhesive or the like as needed.

[0073] The pair of protection plates 15, 15 can protect both ends of the SiC ingot 10 to prevent chipping and cracking of both ends. Therefore, multiple grooves 11 can be formed close to the edge of both end faces, and more SiC wafers 100 described later can be obtained by cutting more.

[0074] Furthermore, when the SiC ingot 10 is clamped and fixed to the rotating shaft, the protection plates 15, 15 may be processed (for example, by drilling holes) as needed before being fixed. Moreover, even in this case, since the SiC ingot 10 itself is not processed, the SiC ingot 10 will not be damaged.

[0075] The plurality of concave grooves 11 of the SiC ingot 10 and the plurality of pad grooves 31 of the polishing pad 30 formed by the above processing steps have the same shape (same pitch) corresponding to the plurality of convex portions 21 of the groove processing drum grindstone 20 .

[0076] Therefore, if Figure 3 As shown, it can be combined with the groove processing step (STEP100 / Figure 1 ) forms a plurality of grooves 11 in the SiC crystal ingot 10 substantially simultaneously, in the polishing step (STEP110 / Figure 1 ), polishing is performed along the groove 11 by using a plurality of pad protrusions 32 (the protrusions between two adjacent pad grooves 31, 31) of the polishing pad 30 having the same pitch as the groove 11.

[0077] Here, the grinding step (STEP110 / Figure 1 ) can be polished by CMP slurry (chemical mechanical liquid abrasive), but powder abrasive (polishing abrasive) can also be added intermittently or continuously to the surface of the polishing pad 30.

[0078] In addition, if Figure 4A As shown, the cutting step (STEP120 / Figure 1 ), a plurality of wires 42 spanning between the wire shafts 41, 41 of the wire saw device 4 of the cutting processing device are arranged in the groove processing step (STEP100 / Figure 1 ) forms a plurality of grooves 11 therein, causing the wire 42 to rotate and advance simultaneously, thereby cutting the SiC ingot 10 into sheets.

[0079] In this case, the plurality of wires 42 can be accurately arranged in the plurality of grooves 11 , and the SiC ingot 10 can be cut into sheets with high accuracy in a single operation.

[0080] In contrast, in the present embodiment, the wire saw device 4 includes an imaging device 44 . The imaging device 44 is provided at a position facing an ingot support device 43 that supports the SiC ingot 10 across the wires 42 , and images the wires 42 disposed in the grooves 11 .

[0081] The ingot support device 43 supports the SiC ingot 10, and its base is composed of, for example, a turntable, which can be rotated in the direction of the arrow around a rotation axis Z extending perpendicularly to the cut surface caused by the multiple lines 42 (extending in the vertical direction in the figure) and can be fixed at any position, thereby having the function of serving as a deviation angle adjustment device.

[0082] The camera device 44 is composed of, for example, a CCD camera, etc. Figure 4B As shown, the slide 47 is connected to the frame 45 of the wire saw device 4 via a hollow frame-shaped connecting plate 46 and is arranged on the front end side of the slide 47 in the hollow frame which is configured to freely move forward and backward on the connecting plate 46 (to be precise, the connecting plate 46 and the auxiliary connecting plate 46′ which is integrally formed on the connecting plate 46), so as to photograph the multiple lines 42 overlapping with the multiple grooves 11.

[0083] Here, the slider 47 may be an electric slider or a manual slider that is manually slidable, and is detachably mounted on the frame 45 of the wire saw device 4 via a connecting plate 46 (equivalent to the mounting and disassembly device of the present invention). In addition, in the present embodiment, the connecting plate 46 is detachably fixed to the frame 45 by being fastened to the frame 45 by screws, but the detachably fixed device is not limited thereto.

[0084] In addition, in the present embodiment, an electric pan / tilt head (up and down motion pan / tilt head) for adjusting focus and zoom is provided between the imaging device 44 and the slider 47, but the electric pan / tilt head may be omitted.

[0085] The cutting step (STEP 120 / Figure 1 ), the deviation angle adjustment step is first performed before cutting.

[0086] In the deviation angle adjustment step, the front end side of the slider 47 is first moved so that the imaging direction of the imaging device 44 is configured to be at a photographing position where multiple grooves 11 and multiple lines 42 overlap (configured to photograph from directly below to directly above the SiC ingot 10 in the figure).

[0087] In this state, a captured image captured by the imaging device 44 is acquired, and the deviation angles 42 of the plurality of lines with respect to the plurality of grooves 11 are detected from the captured image.

[0088] At this time, the camera device 44 can be slid by the slider 47 to continuously take pictures. Accordingly, even if a single shot cannot capture all the multiple lines 42 of the multiple grooves 11 in the camera image, the deviation angles of all the multiple lines 42 relative to the multiple grooves 11 can be detected by scanning and continuously photographing.

[0089] Specifically, if Figure 5As shown in the actual camera image, the deviation angle (whether they are parallel) between the running direction of the groove (left-right direction in the figure) and the running direction of the line 42 (left-right direction in the figure) can be detected.

[0090] The detection of the deviation angle can be performed by visual observation, but for example, the camera image can be binarized and then edge detection processing can be performed, and the moving direction of the width position (upper and lower positions) of the groove 11 and the moving direction of the width position (upper and lower positions) of the line 42 can be detected as straight lines, respectively. Through image processing, the deviation angle can be detected from the inclination of these straight lines.

[0091] Next, the support device 43 is rotated about the rotation axis Z so that the detected deviation angle is offset to zero, and after confirming that the deviation angle is zero in the captured image, the SiC ingot 10 is fixed at its position.

[0092] Here, the angle adjustment device is constituted by an electric turntable. If it is a structure that can be automatically adjusted according to the camera image, it can also be constituted to feedback control the output of the turntable's stepping motor using the deviation corresponding to the inclination between the above-mentioned straight lines as the output step number.

[0093] When the deviation angle is adjusted, the front end of the slider 47 is moved back and evacuated. 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 connecting device 44 will not be hindered or damaged in the subsequent cutting step.

[0094] In this way, the plurality of wires 42 can be accurately arranged in the plurality of grooves 11 , and the SiC ingot 10 can be cut into sheets with high accuracy in a single operation.

[0095] And, if Figure 5 As shown, since the periphery of the SiC wafer 100 obtained by cutting into slices is uniformly chamfered at the corners by the polishing pads 30 with the pitch accurately set to be uniform, it is not necessary to perform chamfering processing after cutting.

[0096] Here, the configuration of the semiconductor crystal wafer (SiC wafer) manufacturing apparatus (cutting apparatus) of the present embodiment can be constituted by the groove processing drum grindstone 20 , the polishing pad 30 , and the wire saw device 4 .

[0097] Then, if Figure 6 As shown, the first surface processing step (STEP130 / Figure 1 ), 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).

[0098] Specifically, the first surface processing step (STEP130 / Figure 1) in which the grinding process is performed by a mechanical polishing device 50 (ultra-high synthetic high-precision grinding process device) for applying mechanical polishing.

[0099] The mechanical polishing device 50 includes a rotating body 51 and a diamond grindstone 53 located on a flat grinding table 52 .

[0100] First, one surface 110 is used as the upper surface and is supported by being sucked onto the porous vacuum chuck 54 of the suction plate of the rotating body 51 , and the other surface 120 is used as the lower surface and is ground by the diamond grindstone 53 .

[0101] At this time, the rotating body 51 and the diamond grindstone 53 are rotationally driven by a driving device (not shown), and the rotating body 51 is pressed against the diamond grindstone 53 by an air compressor (not shown) to perform grinding on the other surface 120 .

[0102] Here, the diamond grindstone 53 may be dressed by a dresser after the grinding process.

[0103] In addition, the mechanical polishing device 50 may have a functional water supply pipe as needed so that a variety of functional water can be used during processing.

[0104] Next, the second surface processing step (STEP140 / 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 one surface 110 is subjected to the same high-precision grinding as the first surface processing step.

[0105] That is, the other surface 120 is used as the upper surface and is adsorbed to the porous vacuum chuck 54 of the adsorption plate of the rotating body 51 , and the one surface 110 is used as the lower surface and is ground by the diamond grindstone 53 .

[0106] At this time, a dresser or the like may be pushed against the diamond grindstone 53 to perform dressing as needed.

[0107] According to the above first surface processing steps (STEP130 / Figure 1 ) and second surface processing steps (STEP140 / Figure 1 ) is subjected to mechanical polishing (high-precision grinding) treatment, in which one side and the other side of the non-transfer cut surface with high flatness obtained by the cutting and grinding step are successively used as the supporting surface (adsorption surface) to perform mechanical polishing (high-precision grinding) on ​​the other side. By doing so, the so-called transfer can be prevented to obtain high-quality SiC wafers, and the previous free grindstone processing steps can be greatly simplified, that is, the complex manufacturing steps such as multiple polishing from one to four times can be greatly simplified.

[0108] More specifically, there is no need to exchange grinding stones for rough grinding and multiple times of fine grinding. For example, a single grinding process can be performed directly using 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.

[0109] Here, the first surface processing step (STEP130 / Figure 1 ) and second surface processing steps (STEP140 / Figure 1 ), the size of the SiC wafer 100 is currently up 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.

[0110] The above description is the details of the method for manufacturing SiC wafers of the present embodiment. As described in detail above, according to the method and apparatus for manufacturing SiC wafers of the present embodiment, for the multiple grooves 11 formed on the entire side of the SiC ingot 10 by the groove processing drum grindstone 20, the multiple wires 42 can be correctly arranged in the multiple grooves 11, and the grooves 11 become guides during cutting, and the wires 42 will not be biased against a single side surface of the grooves 11 (for example, the surface on one side in the width direction), so that the cutting part of the wires is concentrated at the bottom of the grooves 11, and the SiC ingot 10 can be cut into sheets with good accuracy by the multiple wires 42 through a single operation.

[0111] In the above embodiment, the pad groove forming process may be changed so that the pad grooves 31 and the pad protrusions 32 have the same shape as the plurality of concave grooves 11 (plurality of protrusions 21 of the groove processing drum grindstone 20 ) surrounding the entire side surface of the SiC ingot 10 .

[0112] Specifically, in the pad groove forming process, a cylindrical pad groove processing grindstone is prepared in advance, and the groove processing drum wheel grindstone 20 and the pad groove processing grindstone are respectively rotated on rotating axes parallel to each other, and the groove processing drum wheel grindstone 20 is pressed against the pad groove processing grindstone, thereby, pad processing grooves (pad processing protrusions) corresponding to the multiple protrusions 21 are formed on the pad groove processing grindstone, and then, the pad groove processing grindstone and the polishing pad 30 are respectively rotated on rotating axes parallel to each other, and the pad groove processing grindstone is pressed against the polishing pad 30, thereby, multiple pad grooves corresponding to the pad processing grooves (pad processing protrusions) can be formed on the side of the polishing pad 30 as a whole.

[0113] In addition, in the method for manufacturing a SiC wafer of the present embodiment, after the above series of processes, a chemical mechanical polishing (CMP) step, a wafer cleaning step, etc. may be performed as needed.

[0114] In addition, in this embodiment, the method of manufacturing a semiconductor crystal wafer is described by taking the case of manufacturing a SiC wafer from a SiC ingot, but the semiconductor crystal is not limited to SiC, and may be gallium arsenide, indium phosphide, silicon, or other compound semiconductors.

[0115] In addition, the groove processing step (STEP100 / Figure 1 ), the SiC ingot 10 is supported to be freely rotatable while being protected at both end faces by a pair of protective plates 15, 15, but the invention is not limited thereto. For example, the pair of protective plates 15, 15 may be omitted and the SiC ingot 10 may be directly fixed to the rotating shaft.

[0116] In addition to the groove processing step (STEP100 / Figure 1 ) other than the step, such as the grinding step (STEP110 / Figure 1 )、Cut step (STEP120 / Figure 1 ), the processing can also be performed while the two end faces of the SiC ingot 10 are protected by a pair of protection plates 15, 15.

[0117] 4 , the present embodiment illustrates the positional relationship between the wire saw device 4 and the SiC ingot 10 by configuring the SiC ingot 10 on the outside of the wound wire 42 and (relatively) moving the wire 42 outward in the circumferential direction (upward in the figure), but is not limited thereto.

[0118] For example, the SiC ingot 10 may be arranged inside the winding wire 42 and the wire 42 may be (relatively) moved inward in the circumferential direction (lower in the figure). In this case, the camera 44 is arranged above the wire 42 (arranged to take a picture from directly above the SiC ingot 10 to directly below).

[0119] Description of Reference Numerals

[0120] 1 SiC crystal (semiconductor crystal)

[0121] 4 Wire saw device

[0122] 10 SiC ingot (semiconductor crystal ingot)

[0123] 11 Groove

[0124] 15,15 A pair of protection plates

[0125] 20 groove processing drum grinding stone

[0126] 21 convex part

[0127] 30 Abrasive pad

[0128] 31 Pad groove

[0129] 32 Pad convex part

[0130] 41 Spool

[0131] 42 lines

[0132] 43 Ingot support device

[0133] 44 Camera Device

[0134] 45 Frame

[0135] 46 Connecting plate (assembly and disassembly device)

[0136] 46′ auxiliary connecting plate

[0137] 47 Slide

[0138] 50 Mechanical polishing device (ultra-high synthetic high-precision grinding device)

[0139] 51 Rotating body

[0140] 52 Grinding table

[0141] 53 Diamond Grinding Stone

[0142] 54 Porous vacuum suction cup (adsorption plate)

[0143] 100 SiC wafer (semiconductor crystal wafer)

[0144] 110 One side

[0145] 120 The other side.

Claims

1. A semiconductor crystal wafer manufacturing device for cutting a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape, the semiconductor crystal wafer manufacturing device comprising: A groove processing drum grindstone is a drum grindstone for forming 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; A wire saw device that causes a plurality of wires disposed in the plurality of grooves to rotate and advance simultaneously, thereby cutting the semiconductor crystal ingot into sheets; an imaging device for imaging the plurality of wires arranged in the plurality of grooves at a position facing an ingot supporting device supporting the semiconductor crystal ingot across the plurality of wires in the wire saw device; and A slider, the camera device being provided at the front end thereof, and the camera device being able to move from the frame of the wire saw device toward the position for taking a picture, and to retreat after taking the picture; in, The deviation angles of the plurality of lines relative to the plurality of grooves are detected from the image captured by the image capturing device.

2. A semiconductor crystal wafer manufacturing device, which cuts a sheet-shaped wafer from a semiconductor crystal ingot ground into a cylindrical shape, the semiconductor crystal wafer manufacturing device comprising: A groove processing drum grindstone is a drum grindstone for forming 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; A wire saw device that causes a plurality of wires disposed in the plurality of grooves to rotate and advance simultaneously, thereby cutting the semiconductor crystal ingot into sheets; an imaging device for imaging the plurality of wires arranged in the plurality of grooves at a position facing an ingot supporting device supporting the semiconductor crystal ingot across the plurality of wires in the wire saw device; A slider having the aforementioned camera device disposed at the front end thereof, and capable of moving the camera device toward the aforementioned position for performing camera imaging; and An installation and disassembly device, which can freely install the sliding member on the wire saw device; in, The deviation angles of the plurality of lines relative to the plurality of grooves are detected from the image captured by the image capturing device.

3. The semiconductor crystal wafer manufacturing apparatus according to claim 1 or 2, in, The slider slides the imaging device at the position, and the imaging device continuously photographs the plurality of lines arranged in the plurality of grooves.

4. The semiconductor crystal wafer manufacturing apparatus according to claim 1 or 2, in, The ingot supporting device includes a deviation angle adjusting device that fixes the semiconductor crystal ingot by rotating it so that a deviation angle detected from the image captured by the imaging device becomes zero.

5. A method for manufacturing a semiconductor crystal wafer, wherein a sheet-shaped wafer is cut from a semiconductor crystal ingot ground into a cylindrical shape, the method comprising: a groove processing step of forming a plurality of grooves surrounding the entire side surface of the semiconductor crystal ingot; and a cutting step of cutting the semiconductor crystal ingot into sheets by rotating and advancing a plurality of wires arranged on the plurality of grooves formed in the groove processing step by a wire saw device; In the groove processing step, the groove processing drum grindstone having a plurality of convex portions corresponding to the plurality of concave grooves formed on the side surface and the semiconductor crystal ingot are respectively rotated on mutually parallel rotation axes, and the groove processing drum grindstone is pressed against the semiconductor crystal ingot, thereby forming the concave grooves; In the aforementioned cutting step, before causing the plurality of wires arranged in the aforementioned plurality of grooves to rotate and advance simultaneously to cut the aforementioned semiconductor crystal ingot into sheets, a slide having a camera device provided on its front end side is caused to move from the frame of the aforementioned wire saw device, and at a position facing an ingot supporting device supporting the aforementioned semiconductor crystal ingot across the plurality of wires, the plurality of wires arranged in the plurality of grooves are photographed by the camera device, and deviation angles of the plurality of wires relative to the plurality of grooves are detected from the photographed images, and the deviation angles are adjusted to zero, and after adjusting the deviation angles, the aforementioned slide is retreated to avoid the deviation angles.

6. A method for manufacturing a semiconductor crystal wafer, wherein a sheet-shaped wafer is cut from a semiconductor crystal ingot ground into a cylindrical shape, the method comprising: a groove processing step of forming a plurality of grooves surrounding the entire side surface of the semiconductor crystal ingot; and a cutting step of cutting the semiconductor crystal ingot into sheets by rotating and advancing a plurality of wires arranged on the plurality of grooves formed in the groove processing step by a wire saw device; In the groove processing step, the groove processing drum grindstone having a plurality of convex portions corresponding to the plurality of concave grooves formed on the side surface and the semiconductor crystal ingot are respectively rotated on mutually parallel rotation axes, and the groove processing drum grindstone is pressed against the semiconductor crystal ingot, thereby forming the concave grooves; In the aforementioned cutting step, before causing the plurality of wires arranged in the aforementioned plurality of grooves to rotate and advance simultaneously to cut the aforementioned semiconductor crystal ingot into sheets, a slide having a camera device provided on its front end side is moved forward, and at a position facing an ingot supporting device supporting the aforementioned semiconductor crystal ingot across the plurality of wires, the plurality of wires arranged in the plurality of grooves are photographed by the camera device, and deviation angles of the plurality of wires relative to the plurality of grooves are detected from the photographed images, and the deviation angles are adjusted to zero, and after adjusting the deviation angles, the slide is removed.

7. The method for manufacturing a semiconductor crystal wafer according to claim 5 or 6, in, In the cutting step, before cutting, the ingot supporting device performs a deviation angle adjustment step to rotate and fix the semiconductor crystal ingot so that the deviation angle detected from the image captured by the imaging device becomes zero.

Images