Method for determining a notch formation location, method for forming a notch, method for manufacturing a wafer, device for determining a notch formation location, device for forming a notch, and a wafer manufacturing system

Abstract

A method for determining a notch formation position in a single crystal used for manufacturing multiple wafers having notches comprises: a position relationship acquisition process for acquiring a position relationship between a plurality of notch formation candidate positions specified based on the crystal orientation of the single crystal and the plane orientation of the single crystal; a first rotation angle calculation process for calculating a first rotation angle such that when the single crystal is rotated around the central axis of the single crystal from a state where the notch formation candidate position is located at a slice start position, the vertical position of the plane orientation and the target plane orientation when viewed from the direction of the central axis becomes identical; and a determination process for determining the notch formation candidate position as the notch formation position such that the absolute value of the first rotation angle is greater than or equal to a specified angle.

Description

Technology Field

[0001] The present invention relates to a method for determining a notch formation location, a method for forming a notch, a method for manufacturing a wafer, an apparatus for determining a notch formation location, an apparatus for forming a notch, and a wafer manufacturing system. Background Technology

[0002] Conventionally, a method for manufacturing a single crystal for slicing by performing cylindrical grinding and forming a notch on a single crystal for grinding, and manufacturing a plurality of wafers by slicing the single crystal for slicing (see, for example, Patent Document 1).

[0003] In the method described in Patent Document 1, a single crystal for grinding is cylindrically ground so that the amount of axial misalignment between the crystal axis extending in the same direction as the crystal orientation of the single crystal ingot (single crystal for grinding) and the center axis of the single crystal for grinding is pre-adjusted. Next, candidate positions for forming a notch in the cylindrically ground single crystal for grinding are detected, and a notch is formed at the detected candidate positions to manufacture a single crystal for slicing. Afterward, the single crystal for slicing is cut into a block, the block is bonded to a work plate based on the notch, and the work plate is mounted to a wire saw. Then, a plurality of wafers are manufactured by slicing the single crystal for slicing with a wire saw. Prior art literature

[0004] Japanese Patent Publication No. 2017-212268 The problem to be solved

[0005] However, on the outer surface of a single crystal for grinding, multiple crystal axes corresponding to the crystal orientation of the crystal center axis exist at equal intervals in the circumferential direction. For example, the crystal orientation of the crystal center axis <100> On the outer surface of the single crystal for grinding, the crystal orientation <110> There are four crystal axes. A notch indicating the plane orientation is formed on one of the multiple crystal axes.

[0006] Patent Document 1 does not disclose how to determine the formation location of a notch from a plurality of crystal axes. Therefore, in the method described in Patent Document 1, when a single crystal for slicing is sliced ​​so that a wafer is obtained in which the plane orientation matches the target plane orientation, there is a risk of damage occurring around the notch.

[0007] The present invention aims to provide a method for determining a notch formation location, a method for forming a notch, a method for manufacturing a wafer, an apparatus for determining a notch formation location, an apparatus for forming a notch, and a wafer manufacturing system, all of which can suppress damage to a wafer during the slicing of a single crystal. means of solving the problem

[0008] The inventors, through repeated research, realized that if the distance from the slice start position to the notch in a single crystal is excessively short, damage to the wafer is likely to occur starting from the cross-sectional shape of the notch formed on the outer periphery of the single crystal during the slice of the single crystal, and thus completed the present invention.

[0009] (1) The method for determining a notch formation position according to the present invention is a method for determining a notch formation position in a single crystal used for manufacturing a plurality of wafers having a notch, and comprises: a position relationship acquisition process for acquiring a position relationship between a plurality of notch formation candidate positions specified based on the crystal orientation of the single crystal and a plane orientation of the single crystal; a first rotation angle calculation process for calculating a first rotation angle such that when the single crystal is rotated around the central axis of the single crystal from a state in which the notch formation candidate position is located at a slice start position, the vertical position of the plane orientation and the target plane orientation when viewed from the central axis direction are the same; and a determination process for determining the notch formation candidate position such that the absolute value of the first rotation angle is greater than or equal to a specified angle as the notch formation position.

[0010] (2) In the method for determining the notch formation position of the present invention, the specified angle is an acute angle, and the determination process is to determine the notch formation candidate position, in which the absolute value of the first rotation angle is 90° or less, as the notch formation position.

[0011] (3) In the method for determining the notch formation position of the present invention, the method comprises a first horizontal rotation angle calculation process for calculating a first horizontal rotation angle such that when the single crystal rotated by the first rotation angle is horizontally rotated around a vertical axis, the plane orientation when viewed from a direction perpendicular to the slice plane of the single crystal matches the target plane orientation, and the determination process preferably determines the notch formation candidate position having the smallest first horizontal rotation angle as the notch formation position when there are multiple notch formation candidate positions in which the absolute value of the first rotation angle is greater than or equal to the specified angle.

[0012] (4) The method for forming a notch according to the present invention includes a notch forming position determining process for determining the notch forming position by any one of (1) to (3) a notch forming position determining process for forming the notch at the notch forming position, and a notch forming process for forming the notch at the notch forming position.

[0013] (5) The method for manufacturing a wafer according to the present invention comprises: a process of forming a notch in the single crystal by the notch forming method of (4); an attachment process of attaching the single crystal to a slicing device such that the plane orientation when viewed from a direction orthogonal to the slicing surface of the single crystal matches the target plane orientation; and a slicing process of manufacturing the plurality of wafers by slicing the single crystal from the slicing start position with the slicing device.

[0014] (6) The method for manufacturing a wafer according to the present invention comprises a notch formation position determination process for determining the notch formation position by the notch formation position determination method of (3), a notch formation process for forming the notch at the notch formation position, a first attachment process and a second attachment process for attaching the single crystal to a slicing device, and a slicing process for manufacturing the plurality of wafers by slicing the single crystal from the slicing start position with the slicing device, wherein if there is no notch formation candidate position in which the absolute value of the first rotation angle is greater than or equal to the specified angle, the notch formation candidate position in which the absolute value of the first rotation angle is less than the specified angle is determined as the notch formation position, and if the notch formation candidate position in which the absolute value of the first rotation angle is greater than or equal to the specified angle is determined as the notch formation position, the notch formation process, and attaching the single crystal to the slicing device such that the plane orientation when viewed from a direction orthogonal to the slicing surface matches the target plane orientation based on the first rotation angle and the first horizontal rotation angle. When the above first attachment process and the above slicing process are performed, and the notch formation candidate position where the absolute value of the first rotation angle is less than the specified angle is determined as the notch formation position, when the single crystal in a state where the notch formation position is located at the slice start position is rotated around the central axis, the vertical position of the target plane orientation and the plane orientation when viewed from the direction of the central axis become different, and furthermore, when the second rotation angle calculation process calculates a second rotation angle greater than the specified angle and the single crystal rotated by the second rotation angle is horizontally rotated around the vertical axis, the plane orientation and the horizontal position of the target plane orientation when viewed from the direction orthogonal to the slice plane become identical, and further,A second horizontal rotation angle calculation process for calculating a second horizontal rotation angle such that the position in the vertical direction is different; a vertical rotation angle calculation process for calculating a vertical rotation angle such that when the single crystal, which has been rotated by the second rotation angle and then horizontally rotated by the second horizontal rotation angle, is vertically rotated around a horizontal axis, the plane orientation when viewed from the direction perpendicular to the slice plane matches the target plane orientation; the notch forming process; and based on the second rotation angle and the second horizontal rotation angle, the second attachment process of attaching the single crystal to the slice device and then vertically rotating it by the vertical rotation angle so that the horizontal position of the plane orientation when viewed from the direction perpendicular to the slice plane and the target plane orientation are the same, and the position in the vertical direction is different, and the slice process is performed.

[0015] (7) The notch formation position determining device of the present invention is a notch formation position determining device for determining a notch formation position in a single crystal used for manufacturing a plurality of wafers having a notch, and comprises a position relationship acquiring unit for acquiring a position relationship between a plurality of notch formation candidate positions specified based on the crystal orientation of the single crystal and a plane orientation of the single crystal, a correction amount calculating unit for calculating a first rotation angle such that when the single crystal is rotated around the central axis of the single crystal from a state where the notch formation candidate position is located at a slice start position, the vertical position of the plane orientation and the target plane orientation when viewed from the central axis direction becomes the same, and a notch formation position determining unit for determining the notch formation candidate position such that the absolute value of the first rotation angle is greater than or equal to a specified angle.

[0016] (8) In the notch formation position determining device of the present invention, the specified angle is an acute angle, and the notch formation position determining part determines the notch formation candidate position, in which the absolute value of the first rotation angle is 90° or less, as the notch formation position.

[0017] (9) In the notch formation position determining device of the present invention, the correction amount calculation unit calculates a first horizontal rotation angle such that when the single crystal rotated by the first rotation angle is horizontally rotated around a vertical axis, the plane orientation when viewed from a direction perpendicular to the slice plane of the single crystal matches the target plane orientation, and the notch formation position determining unit determines the notch formation candidate position with the smallest first horizontal rotation angle as the notch formation position when there are multiple notch formation candidate positions in which the absolute value of the first rotation angle is greater than or equal to the specified angle.

[0018] (10) The notch forming device of the present invention comprises one of (7) to (9) a notch forming position determining device and a notch forming part that forms the notch at the notch forming position.

[0019] (11) The wafer manufacturing system of the present invention comprises a notch forming device of (10), a slicing device for manufacturing a plurality of wafers by slicing the single crystal from the slicing start position, and an attachment device for attaching the single crystal to the slicing device such that the plane orientation when viewed from a direction orthogonal to the slicing plane of the single crystal matches the target plane orientation.

[0020] (12) The wafer manufacturing system of the present invention comprises a notch forming position determining device of (9), a notch forming unit that forms the notch at the notch forming position, a slicing device that manufactures the plurality of wafers by slicing the single crystal from the slicing start position, an attachment device that attaches the single crystal to the slicing device, and a vertical rotation angle calculation unit. The notch forming position determining device determines the notch forming candidate position where the absolute value of the first rotation angle is greater than or equal to the specified angle as the notch forming position when there is no such notch forming candidate position where the absolute value of the first rotation angle is less than the specified angle, and when the notch forming candidate position where the absolute value of the first rotation angle is greater than or equal to the specified angle is determined as the notch forming position, the attachment device attaches the single crystal to the slicing device based on the first rotation angle and the first horizontal rotation angle such that the plane orientation when viewed from a direction orthogonal to the slicing plane matches the target plane orientation, and the slicing device attaches the single crystal attached by the attachment device. When slicing, and when the notch formation candidate position where the absolute value of the first rotation angle is less than the specified angle is determined as the notch formation position, the correction amount calculation unit calculates a second horizontal rotation angle such that when the single crystal in a state where the notch formation position is located at the slice start position is rotated around the central axis, the vertical position of the plane orientation viewed from the direction of the central axis becomes different from the vertical position of the target plane orientation, and also calculates a second rotation angle greater than the specified angle, and when the single crystal rotated by the second rotation angle is horizontally rotated around the vertical axis, the horizontal position of the plane orientation viewed from the direction orthogonal to the slice plane becomes the same from the vertical position of the target plane orientation, and also calculates a second horizontal rotation angle such that the vertical position becomes different, and the vertical position becomes different. The vertical rotation angle calculation unit,After rotating the single crystal by the second rotation angle and then rotating it horizontally by the second horizontal rotation angle, the single crystal is vertically rotated around a horizontal axis, and a vertical rotation angle is calculated such that the plane orientation when viewed from a direction perpendicular to the slice plane coincides with the target plane orientation; the attachment device attaches the single crystal to the slice device based on the second rotation angle and the second horizontal rotation angle such that the horizontal position of the plane orientation when viewed from a direction perpendicular to the slice plane and the target plane orientation are identical, and the vertical position is different; and the slice device vertically rotates the single crystal attached by the attachment device by the vertical rotation angle and then slices it. Brief explanation of the drawing

[0021] FIG. 1a is a schematic diagram showing the characteristics of a single crystal for grinding according to an embodiment. FIG. 1b is a schematic diagram showing the characteristics of a wafer manufactured from a single crystal for grinding according to an embodiment. FIG. 2 is a block diagram showing the schematic processing of a wafer manufacturing system according to an embodiment. FIG. 3 is a plan view showing the schematic configuration of a cylindrical grinding device according to an embodiment. FIG. 4 is a block diagram showing the configuration of a cylindrical grinding device according to an embodiment. FIG. 5 is a block diagram showing the configuration of an attachment device according to an embodiment. FIG. 6 is a schematic diagram showing the schematic configuration of a slicing device according to an embodiment. FIG. 7 is a block diagram showing the configuration of a slicing device according to an embodiment. FIG. 8 is a flowchart illustrating a method for manufacturing a wafer according to an embodiment. FIG. 9 is a flowchart showing a notch formation position determination process according to an embodiment. FIG. 10 is a flowchart showing a notch formation position determination process according to an embodiment. FIG. 11 is an explanatory diagram schematically illustrating a notch formation positioning process according to an embodiment. FIG. 12a is a schematic diagram showing the relationship between the first horizontal rotation angle and the size of the single material according to an embodiment, and shows the state in which a single crystal for slicing is horizontally rotated by the first horizontal rotation angle. FIG. 12b is a schematic diagram showing the relationship between the first horizontal rotation angle and the size of the single material according to an embodiment, and shows a state in which a single crystal for slicing is horizontally rotated by a first horizontal rotation angle larger than FIG. 12a. FIG. 13 is a flowchart showing the first attachment process according to an embodiment. FIG. 14 is an explanatory diagram schematically showing a process from a first attachment process or a second attachment process to a slicing process according to an embodiment. FIG. 15 is a flowchart showing a second attachment process according to an embodiment. FIG. 16a is a schematic diagram showing the characteristics of a single crystal for grinding according to a modified example, and the crystal orientation of the crystal center axis is <110> It shows the characteristics of a single crystal for grinding. FIG. 16b is a schematic diagram showing the characteristics of a single crystal for grinding according to a modified example, and the crystal orientation of the crystal center axis is <111> It shows the characteristics of a single crystal for grinding. Specific details for implementing the invention

[0022] (Form for carrying out the invention)

[0023] [Embodiment]

[0024] Hereinafter, an embodiment of the present invention will be described.

[0025] Characteristics of Single Crystals and Wafers for Grinding

[0026] First, the characteristics of the single crystal for grinding used in the present embodiment and the wafer manufactured from said single crystal for grinding will be described. FIG. 1a is a schematic diagram showing the characteristics of the single crystal for grinding. FIG. 1b is a schematic diagram showing the characteristics of the wafer manufactured from the single crystal for grinding.

[0027] The grinding single crystal (T1) shown in FIG. 1a is formed into a cylindrical shape and is obtained from a silicon single crystal ingot (T) (see FIG. 2) manufactured by the Czochralski method, etc. The grinding single crystal (T1) is used to manufacture a slicing single crystal (T2) (see FIG. 2). Additionally, the grinding single crystal (T1) may be composed of germanium, silicon carbide, gallium arsenide, indium arsenide, gallium nitride, or aluminum nitride, etc.

[0028] The crystal orientation of the crystal center axis (Ct) of the single crystal (T1) for grinding is, <100> is. On the outer surface of the single crystal (T1) for grinding, the crystal orientation is <110> There are four crystal axes that exist at 90° intervals in the circumferential direction. These four crystal axes become candidate positions (Q) for forming a notch (N) (hereinafter referred to as “candidate notch formation positions (Q)”). If there are four candidate notch formation positions (Q) (hereinafter each candidate notch formation position (Q) may be referred to as “first candidate notch formation position (Q1),” “second candidate notch formation position (Q2),” “third candidate notch formation position (Q3),” and “fourth candidate notch formation position (Q4)”), there are also four ways in which the plane orientation (M) of the single crystal (T1) for grinding appears based on the candidate notch formation positions (Q).

[0029] The notch (N) shown in FIG. 1b is formed at one of four candidate notch formation positions (Q). The notch (N) represents the plane orientation (Mw) (hereinafter referred to as "target plane orientation (Mw)") of a wafer (W) obtained from a single crystal (T1) for grinding. The notch (N) is located at a position where the angle formed by a virtual line connecting the notch (N) and the center axis (Cw) of the wafer (W) (hereinafter referred to as "wafer center axis (Cw)") and a virtual line connecting the target plane orientation (Mw) and the wafer center axis (Cw) is a set angle (α). A wafer (W) is manufactured by slicing a single crystal (T2) such that, when viewed from a direction orthogonal to the slicing plane of the single crystal (T2) (hereinafter referred to as the "direction orthogonal to the slicing plane"), the plane orientation (M) and the target plane orientation (Mw) coincide.

[0030] <Overview of Wafer Manufacturing System Process and Configuration>

[0031] Next, the schematic processing and configuration of a wafer manufacturing system used for manufacturing a wafer (W) will be described. FIG. 2 is a block diagram showing the schematic processing of a wafer manufacturing system. FIG. 3 is a plan view showing the schematic configuration of a cylindrical grinding device. FIG. 4 is a block diagram showing the configuration of a cylindrical grinding device. FIG. 5 is a block diagram showing the configuration of an attachment device. FIG. 6 is a schematic diagram showing the schematic configuration of a slicing device. FIG. 7 is a block diagram showing the configuration of a slicing device.

[0032] The wafer manufacturing system (1) shown in FIG. 2 manufactures a wafer (W) using a silicon single-crystal ingot (T) having a shoulder portion (Ta), a linear portion (Tb), and a tail portion (Tc). The wafer manufacturing system (1) is equipped with a block processing device (2), a cylindrical grinding device (3), an attachment device (4), and a slicing device (5).

[0033] The block processing device (2) is equipped with an outer grinding device (21) and a band saw (22).

[0034] The outer grinding device (21) grinds the linear portion (Tb) of the silicon single crystal ingot (T) into a cylindrical shape.

[0035] The band saw (22) cuts the shoulder portion (Ta) and tail portion (Tc) from the silicon single crystal ingot (T) ground by the outer grinding device (21) and processes it into a grinding single crystal (T1) consisting of a linear portion (Tb).

[0036] The cylindrical grinding device (3) manufactures a single crystal (T2) for slicing by performing cylindrical grinding of the single crystal (T1) for slicing in a state where the crystal center axis (Ct) of the single crystal (T1) for slicing and the rotation axis (C) during cylindrical grinding (see FIG. 3) are positioned on the same axis. Additionally, the cylindrical grinding device (3) forms a notch (N) in the single crystal (T2) for slicing. The single crystal (T2) for slicing manufactured by the cylindrical grinding device (3) is cut into multiple blocks of a length that can be attached to the slicing device (5) by a band saw (22). Additionally, if the length of the single crystal (T2) for slicing is a length that can be attached to the slicing device (5), the band saw (22) may not cut the single crystal (T2) for slicing into multiple blocks.

[0037] The attachment device (4) attaches a single crystal (T2) for slicing to the slicing device (5).

[0038] The slicing device (5) is configured, for example, by a wire saw, and processes a single crystal (T2) for slicing into a plurality of wafers (W), each having a notch (N), by slicing.

[0039] Additionally, the wafer manufacturing system (1) may manufacture a single crystal (T2) for slicing having a notch (N) by cutting a single crystal (T1) for grinding into multiple blocks of a length that can be attached to a slicing device (5) by a band saw (22), and performing the aforementioned processing on each block by a cylindrical grinding device (3).

[0040] <Composition of the Cylindrical Grinding Device>

[0041] As shown in FIGS. 3 and 4, the cylindrical grinding device (3) comprises a grinding section (31), a first orientation measuring section (32), a notch forming section (33), and a control device (34). Additionally, the arrangement positions of each component of the cylindrical grinding device (3) will be explained based on the direction shown in FIG. 3.

[0042] The grinding unit (31) is equipped with a first rotation processing unit (311), a grinding unit (312), and a relative movement unit (313).

[0043] The first rotational processing unit (311) holds and supports a single crystal (T1) for grinding and performs rotational processing around a rotation axis (C) that extends in the left and right directions. The first rotational processing unit (311) has a pair of rotational holding support units (314) and a rotational holding support unit moving unit (not illustrated) that moves the pair of rotational holding support units (314) closer together or apart along the rotation axis (C).

[0044] Each rotational holding support unit (314) is equipped with a chuck (315) that holds and supports the end of the crystal center axis (Ct) of the grinding single crystal (T1), and a chuck driving unit (316) that rotates the chuck (315) around the rotation axis (C).

[0045] The first rotation processing unit (311) rotates a single crystal (T1) for grinding by holding and supporting it with the chuck (315) of each rotation holding support unit (314) in a state where the crystal center axis (Ct) coincides with the rotation axis (C).

[0046] The grinding unit (312) comprises a grinding member (317) and a grinding member moving part (318) that moves the grinding member (317) toward or away from a single crystal (T1) for grinding. The grinding member (317) contacts a rear portion of the single crystal (T1) for grinding, which rotates by the drive of the first rotation processing part (311), and grinds the single crystal (T1) for grinding.

[0047] The relative moving unit (313) moves the grinding unit (312) along the axis of rotation (C) relative to the rotational holding support unit (314). By moving the grinding unit (312) along the axis of rotation (C) while bringing the grinding member (317) into contact with the rotating single crystal (T1) for grinding, the single crystal (T1) for grinding can be cylindrically ground.

[0048] Additionally, when performing cylindrical grinding, the rotational holding support unit (314) may be moved along the rotational axis (C) without moving the grinding unit (312), or both the grinding unit (312) and the rotational holding support unit (314) may be moved along the rotational axis (C).

[0049] The first orientation measuring unit (32) measures the plane orientation (M) and crystal axis of a grinding single crystal (T1) held and supported by the first rotational processing unit (311). The first orientation measuring unit (32) includes an X-ray unit (321) for measuring the plane orientation (M) and crystal axis, and an X-ray unit moving unit (not shown) for moving the X-ray unit (321) left and right in front of the grinding single crystal (T1) held and supported by the rotational holding support unit (314).

[0050] The X-ray unit (321) measures the plane orientation (M) or crystal axis by irradiating with X-rays and outputs a signal indicating the measurement result.

[0051] The notch forming part (33) forms a notch (N) in the single crystal (T2) for slicing.

[0052] The control device (34) is equipped with an input unit (341), a memory unit (342), and a control unit (343).

[0053] The input unit (341) is configured, for example, by a touch panel or a physical button. The input unit (341) is used, for example, for inputting various settings regarding the operation of the cylindrical grinding device (3) by an operator, and outputs a signal corresponding to the input operation to the control unit (343).

[0054] The memory unit (342) stores various information regarding the determination process of the notch (N) formation position (hereinafter referred to as the “notch formation position”) and the cylindrical grinding process so that it can be read by the control unit (343). Examples of the various information include the diameter and length of the single crystal for grinding (T1) and the single crystal for slicing (T2), the target plane orientation (Mw), the positional relationship between the first, second, third, and fourth notch formation candidate positions (Q1, Q2, Q3, Q4) and the plane orientation (M), the notch formation position, the specified angle (β) shown in FIG. 11, the first rotation angle (φ1) and the first horizontal rotation angle (θ1), the additional angle (φa), the second rotation angle (φ2), and the second horizontal rotation angle (θ2) shown in FIG. 14.

[0055] The control unit (343) is equipped with a CPU and realizes various functions by having the CPU execute a program stored in the memory unit (342). The control unit (343) is equipped with a position relationship acquisition unit (344), a correction amount calculation unit (345), a notch formation position determination unit (346), a grinding control unit (347), and a notch formation control unit (348). The position relationship acquisition unit (344), the correction amount calculation unit (345), and the notch formation position determination unit (346) constitute a notch formation position determination device. The notch formation position determination device, the notch formation unit (33), and the notch formation control unit (348) constitute a notch formation device.

[0056] The position relationship acquisition unit (344) acquires the position relationship between each notch formation candidate position (Q) and the plane orientation (M) of the grinding single crystal (T1).

[0057] The correction amount calculation unit (345) calculates the first and second rotation angles (φ1, φ2) and the first and second horizontal rotation angles (θ1, θ2) of the single crystal (T2) for slicing when manufacturing a wafer (W) using the single crystal (T2) for slicing.

[0058] The notch formation position determining unit (346) determines one of the plurality of notch formation candidate positions (Q) as the notch formation position based on the first rotation angle (φ1), the first horizontal rotation angle (θ1), and the specified angle (β).

[0059] The grinding control unit (347) controls the grinding unit (31) to rotate the single crystal (T1) for grinding and performs cylindrical grinding by moving the grinding member (317) along the axis of rotation (C) while bringing it into contact with the single crystal (T1) for grinding. Through this cylindrical grinding, a single crystal (T2) for slicing is obtained.

[0060] The notch formation control unit (348) controls the notch formation unit (33) to form a notch (N) at a notch formation position on the outer surface of the single crystal (T2) for slicing.

[0061] <Configuration of the Attachment Device>

[0062] As shown in FIG. 5, the attachment device (4) is equipped with a second rotation processing unit (41), a second orientation measuring unit (42), a single crystal bonding processing unit (43), a horizontal rotation processing unit (44), a slice base bonding processing unit (45), an attachment processing unit (46), and a control device (47).

[0063] The second rotation processing unit (41) is provided with a pair of rollers (411) (see FIG. 14) formed so that their rotation axes are parallel to each other and are arranged in a horizontal direction. A single crystal (T2) for slicing is placed on the pair of rollers (411) in such a state that the rotation axis of the pair of rollers (411) and the crystal center axis (Ct) are parallel. The second rotation processing unit (41) rotates the single crystal (T2) for slicing around the crystal center axis (Ct) by rotating the pair of rollers (411).

[0064] The second orientation measuring unit (42) is equipped with an X-ray unit not shown, measures the plane orientation of a single crystal (T2) for slicing on a pair of rollers (411) by the X-ray unit, and outputs a signal indicating the measurement result.

[0065] The single crystal adhesive treatment unit (43) adheres a single crystal (T2) for slicing on a pair of rollers (411) of the second rotational treatment unit (41) to a slicing plate (532).

[0066] The horizontal rotation processing unit (44) rotates the slice plate (532), on which the single crystal (T2) for slicing is attached, horizontally around a vertical axis (D) (see FIG. 11) that is orthogonal to and intersects the central axis (Ct).

[0067] The slicing plate adhesive treatment section (45) adhesively attaches a slicing plate (532), which is horizontally rotated together with a slicing single crystal (T2) around a vertical axis (D), to a work plate (531).

[0068] The attachment processing unit (46) attaches the work plate (531) of the fixing member (53) to the attachment unit (54) in a reference attachment state. The reference attachment state is a state in which the longitudinal direction of the work plate (531) of the fixing member (53) and the direction perpendicular to the slice surface are parallel.

[0069] The control device (47) is equipped with an input unit (471), a memory unit (472), and an attachment control unit (473).

[0070] The input section (471) is configured in the same way as the input section (341) of the cylindrical grinding device (3).

[0071] The memory unit (472) stores various information regarding the attachment process of a single crystal (T2) for slicing so that it can be read by the attachment control unit (473). In the memory unit (472), for example, based on input operation by the input unit (471), the target surface orientation (Mw), the positional relationship between the notch formation position and the surface orientation (M) obtained by the control unit (343) of the cylindrical grinding device (3), the first rotation angle (φ1), the first horizontal rotation angle (θ1), the second rotation angle (φ2), and the second horizontal rotation angle (θ2) are stored.

[0072] The attachment control unit (473) is equipped with a CPU, and various functions are realized by the CPU executing a program stored in the memory unit (472).

[0073] The attachment control unit (473) controls the second rotation processing unit (41), the second orientation measuring unit (42), the single crystal adhesive processing unit (43), the horizontal rotation processing unit (44), the slice base adhesive processing unit (45), and the attachment processing unit (46) to attach a single crystal (T2) for slicing to the slicing device (5).

[0074] <Configuration of the Slicing Device>

[0075] As shown in FIGS. 6 and 7, the slicing device (5) comprises a slicing section (51), a lifting section (52), and a control device (57).

[0076] The slice section (51) is equipped with a total of three main rollers (511), two of which are placed on the same horizontal plane and one is placed below the middle of the two.

[0077] Three main rollers (511) are arranged so that their rotation axes are parallel to each other and perpendicular to the vertical direction. Wires (512) are wound around the three main rollers (511) along their axial directions. By winding the wires (512) onto these main rollers (511), a wire row is formed between the two upper main rollers (511) (hereinafter referred to as "upper main rollers (511A)") in which a plurality of wires (512) are arranged at a constant pitch along the axial direction of the main rollers (511). The direction in which the wires (512) of the wire row are arranged is parallel to the direction perpendicular to the slice plane.

[0078] Wire reels (514, 515) are arranged at both ends of the wire (512) to feed or wind the wire (512) through guide rollers (513).

[0079] Above the upper main roller (511A), a nozzle (516) for supplying slurry (G) is positioned at the intermediate position between the two upper main rollers (511A).

[0080] The lifting unit (52) raises the single crystal (T2) for slicing above the nozzle (516) relative to the wire (512). The lifting unit (52) is equipped with a fixing member (53), an attachment part (54), a vertical rotation processing part (55), and a lifting drive part (56).

[0081] The fixing member (53) comprises a rectangular plate-shaped work plate (531) that is held and supported by the attachment part (54), and a slicer (532) that is attached to the work plate (531).

[0082] The slicing plate (532) is a member in the shape of a roughly rectangular plate and is cut by a wire (512) together with a single crystal (T2) for slicing. The slicing plate (532) is provided with a fixed surface (532A) in the shape of an arc, to which the single crystal (T2) for slicing is fixed through an adhesive. The single crystal (T2) for slicing is fixed to the fixed surface (532A) such that the longitudinal direction of the slicing plate (532) is parallel to the direction of the crystal center axis (Ct) of the single crystal (T2) for slicing. The flat surface of the slicing plate (532), opposite to the fixed surface (532A), is bonded to the work plate (531).

[0083] The attachment part (54) is provided with a holding support mechanism that, for example, holds and supports a work plate (531). The work plate (531) of the fixing member (53) is attached to the attachment part (54).

[0084] The vertical rotation processing unit (55) vertically rotates the attachment unit (54) around a horizontal axis (E) that is orthogonal to the direction orthogonal to the slice surface and the vertical direction.

[0085] The lifting drive unit (56) lifts the attachment unit (54) and the vertical rotation processing unit (55).

[0086] The control device (57) is equipped with an input unit (571), a memory unit (572), and a control unit (573).

[0087] The input section (571) is configured in the same way as the input section (341) of the cylindrical grinding device (3).

[0088] The memory unit (572) stores various information regarding slice processing so that it can be read by the attachment control unit (473). Examples of such information include the vertical rotation angle (λ) shown in FIG. 14. Additionally, the memory unit (572) stores, for example, the target surface orientation (Mw), the positional relationship between the notch formation position and the surface orientation (M) obtained by the control unit (343) of the cylindrical grinding device (3), the second rotation angle (φ2), and the second horizontal rotation angle (θ2), based on input operations by the input unit (571).

[0089] The control unit (573) is equipped with a CPU, and various functions are realized by the CPU executing a program stored in the memory unit (572). The control unit (573) is equipped with a vertical rotation angle calculation unit (574) and a slice control unit (575).

[0090] The vertical rotation angle calculation unit (574) calculates the vertical rotation angle (λ).

[0091] The slice control unit (575) controls the slice unit (51) and the lifting unit (52) to manufacture a plurality of wafers (W) from a single crystal (T2) for slicing.

[0092] A slicing device (5) having the above configuration manufactures a plurality of wafers (W) by slicing a single crystal (T2) by lowering it and pressing it against a wire row while supplying a slurry (G) between two upper main rollers (511A) and driving a wire (512) in a direction approximately orthogonal to the axial direction of the main rollers (511) by rotating a plurality of main rollers (511), and by slicing a single crystal (T2) for slicing.

[0093] Additionally, the slicing device (5) may be configured to start slicing from the top of the single crystal (T2) for slicing when viewed from a direction orthogonal to the slicing surface.

[0094] <Wafer Manufacturing Method>

[0095] Next, a method for manufacturing a wafer (W) using a wafer manufacturing system (1) will be described. FIG. 8 is a flowchart illustrating a method for manufacturing a wafer. FIG. 9 and FIG. 10 are flowcharts illustrating a notch formation position determination process. FIG. 11 is an explanatory diagram schematically illustrating a notch formation position determination process. FIG. 12 is a schematic diagram illustrating the relationship between a first horizontal rotation angle and the size of a single material, FIG. 12a shows a state in which a single crystal for slicing is horizontally rotated by a first horizontal rotation angle, and FIG. 12b shows a state in which a single crystal for slicing is horizontally rotated by a first horizontal rotation angle greater than FIG. 12a. FIG. 13 is a flowchart illustrating a first attachment process. FIG. 14 is an explanatory diagram schematically illustrating a process from the first attachment process or the second attachment process to the slicing process. FIG. 15 is a flowchart illustrating a second attachment process.

[0096] A working device or operator who is not in the city holds and supports a cylindrical grinding single crystal (T1) obtained by processing of a block processing device (2) in a rotational holding support unit (314) of a cylindrical grinding device (3) in a state where the crystal center axis (Ct) coincides with the rotation axis (C).

[0097] Next, as shown in FIG. 8, the control unit (343) of the cylindrical grinding device (3) determines a notch formation position from a plurality of notch formation candidate positions (Q) (Step S1: Notch formation position determination process). The notch formation position determination process of Step S1 includes the processing of Steps S11 to S20 shown in FIG. 9 and FIG. 10.

[0098] First, the position relationship acquisition unit (344) of the control unit (343) acquires the position relationship between each notch formation candidate position (Q) and the plane orientation (M) of the single crystal (T1) for grinding (Step S11: position relationship acquisition process).

[0099] In step S11, the position relationship acquisition unit (344) controls the chuck drive unit (316) to rotate the grinding single crystal (T1) and controls the first orientation measuring unit (32) to acquire measurement results of all crystal axes present in the grinding single crystal (T1). The position relationship acquisition unit (344) sets the crystal axis measured at the nth (n is a natural number) as the nth notch formation candidate position (Qn). The position relationship acquisition unit (344) controls the chuck drive unit (316) to rotate the grinding single crystal (T1) and stops it in a position where the first notch formation candidate position (Q1) is located at the highest position. The position relationship acquisition unit (344) controls the first orientation measuring unit (32) to acquire measurement results of the position relationship between the first notch formation candidate position (Q1) and the surface orientation (M), as shown in the first drawing from the left at the top of FIG. 11. The position relationship acquisition unit (344) performs the same processing for each other notch formation candidate position (Q) and acquires the measurement results of the position relationship between each notch formation candidate position (Q) and the plane orientation (M) as shown in each drawing at the top of FIG. 11.

[0100] The correction amount calculation unit (345) calculates a first rotation angle (φ1) corresponding to each notch formation candidate position (Q) (Step S12: first rotation angle calculation process).

[0101] In step S12, the correction amount calculation unit (345) calculates the first rotation angle (φ1) corresponding to the first notch formation candidate position (Q1) such that when the first notch formation candidate position (Q1) is rotated from the state where the first notch formation candidate position (Q1) is located at the slice start position (P) while the single crystal (T2) for slicing is viewed from the direction of the crystal center axis (Ct), the vertical position of the plane orientation (M) and the target plane orientation (Mw) when viewed from the direction of the crystal center axis (Ct) is the same, as shown in the first drawing from the left at the bottom of FIG. 11. The correction amount calculation unit (345) performs the same processing for each other notch formation candidate position (Q) and calculates the first rotation angle (φ1) corresponding to each notch formation candidate position (Q) as shown in each drawing at the bottom of FIG. 11.

[0102] The correction amount calculation unit (345) calculates a first horizontal rotation angle (θ1) corresponding to each notch formation candidate position (Q) (Step S13: first horizontal rotation angle calculation process).

[0103] In step S13, the correction amount calculation unit (345) calculates the angle that can make the horizontal position of the plane orientation (M) and the target plane orientation (Mw) identical when viewed from a direction perpendicular to the slice plane, as shown in the first drawing from the left at the bottom of FIG. 11, when the sliced ​​single crystal (T2) rotated by the first rotation angle (φ1) is horizontally rotated around the vertical axis (D). The correction amount calculation unit (345) performs the same processing for each other notch formation candidate position (Q) and calculates the first horizontal rotation angle (θ1) corresponding to each notch formation candidate position (Q) as shown in each drawing at the bottom of FIG. 11.

[0104] The notch formation position determining unit (346) determines whether there exists a notch formation candidate position (Q) in which the absolute value of the first rotation angle (φ1) is greater than or equal to the specified angle (β) and less than or equal to 90° (step S14).

[0105] The specified angle (β) is set based on the following reasons. When a single crystal (T2) for slicing is cut by a slicing device (5), if the circumferential distance from the slicing start position (P) to the notch (N) is excessively short, there is a risk of damage occurring around the notch (N). If heat treatment is performed on a damaged wafer (W) for, for example, to manufacture a device, the damage may become the starting point for the occurrence of slip dislocations, which may affect the manufacturing yield of the device. The specified angle (β) is set as an angle that can prevent such damage from occurring.

[0106] As for the regulated angle (β), 30° or more and 45° or less can be exemplified.

[0107] In addition, the specified angle (β) used in the notch formation position determination process may be the same value regardless of the diameter of the single crystal (T2) for slicing, or it may be different depending on the diameter of the single crystal (T2) for slicing.

[0108] In step S14, the notch formation position determining unit (346) determines whether there exists a notch formation candidate position (Q) in which the absolute value of the first rotation angle (φ1) is greater than or equal to the specified angle (β) and less than or equal to 90° (step S14: YES), and determines whether there exist multiple notch formation candidate positions (Q) that satisfy the determination criteria of step S14 (where the absolute value of the first rotation angle (φ1) is greater than or equal to the specified angle (β) and less than or equal to 90°) (step S15).

[0109] In step S15, if the notch formation position determining unit (346) determines that there are multiple notch formation candidate positions (Q) that satisfy the determination criteria of step S14 (step S15: YES), it performs a first determination process (step S16).

[0110] In step S16, the notch formation position determining unit (346) determines the notch formation candidate position (Q) that satisfies the judgment criteria of step S14 and has the smallest first horizontal rotation angle (θ1) as the notch formation position.

[0111] The reason for determining the notch formation position by the first crystallization process of step S16 is explained. As shown in FIG. 12a, when a single crystal (T2) for slicing, in which the crystal center axis (Ct) is parallel to the direction orthogonal to the slice plane, is horizontally rotated by a first horizontal rotation angle (θ11) and then a wafer (W) is manufactured, the two end portions of the single crystal (T2) for slicing that appear as diagonal lines become a single material (Te) that cannot be obtained from the wafer (W). As shown in FIG. 12b, when the single crystal (T2) for slicing is horizontally rotated by a first horizontal rotation angle (θ12) which is greater than the first horizontal rotation angle (θ11), the single material (Te) becomes larger than when it is horizontally rotated by the first horizontal rotation angle (θ11). In order to make the size of this single material (Te) smaller, the notch formation position is determined by the first crystallization process of step S16.

[0112] In step S15, if the notch formation position determining unit (346) determines that there are no multiple notch formation candidate positions (Q) satisfying the determination criteria of step S14 (step S15: NO), it performs a second determination process (step S17).

[0113] In step S17, the notch formation location determining unit (346) determines the only notch formation candidate location (Q) that satisfies the determination criteria of step S14 as the notch formation location.

[0114] In step S14, the notch formation position determining unit (346) determines that there is no notch formation candidate position (Q) in which the absolute value of the first rotation angle (φ1) is greater than or equal to the specified angle (β) and less than or equal to 90°, that is, that the absolute value of the first rotation angle (φ1) corresponding to all notch formation candidate positions (Q) is less than the specified angle (β) (step S14: NO), and performs a third determination process as shown in FIG. 10 (step S18).

[0115] In step S18, the notch formation position determining unit (346) determines the notch formation candidate position (Q) as the notch formation position, where the absolute value of the first rotation angle (φ1) is less than the specified angle (β) and the first horizontal rotation angle (θ1) is the smallest.

[0116] The correction amount calculation unit (345) calculates a second rotation angle (φ2) corresponding to the notch formation position determined by the third determination process (Step S19: second rotation angle calculation process).

[0117] In step S19, the correction amount calculation unit (345) uses the specified angle (β) as an additional angle (φa) and calculates the angle obtained by adding the additional angle (φa) to the first rotation angle (φ1), that is, an angle greater than the specified angle, as the second rotation angle (φ2), as shown in the second drawing from the left at the bottom of FIG. 14.

[0118] When a notch (N) is formed at a notch formation position determined by a third crystallization process, if the single crystal (T2) for slicing is rotated by a second rotation angle (φ2) around the crystal center axis (Ct) from the state where the notch (N) is located at the slice start position (P), the vertical position of the plane orientation (M) and the target plane orientation (Mw) when viewed from the direction of the crystal center axis (Ct) is different regardless of the size of the first rotation angle (φ1).

[0119] Additionally, the correction amount calculation unit (345) may calculate a specific preset angle greater than the specified angle (β) as the second rotation angle (φ2).

[0120] The correction amount calculation unit (345) calculates a second horizontal rotation angle (θ2) corresponding to the notch formation position determined by the third determination process (Step S20: second horizontal rotation angle calculation process).

[0121] In step S20, the correction amount calculation unit (345) calculates the second horizontal rotation angle (θ2) such that when the single crystal (T2) for slicing, in which the notch (N) is located at the slice start position (P), is rotated by a second rotation angle (φ2) and then rotated horizontally around the vertical axis (D), the horizontal position of the plane orientation (M) and the target plane orientation (Mw) when viewed from the direction perpendicular to the slice plane are the same, as shown in the third drawing from the left at the bottom of FIG. 14. When the single crystal (T2) for slicing, in which the notch (N) is located at the slice start position (P), is rotated by a second rotation angle (φ2) and then rotated horizontally by a second horizontal rotation angle (θ2), the vertical position of the plane orientation (M) and the target plane orientation (Mw) when viewed from the direction perpendicular to the slice plane is different.

[0122] In the example shown in each drawing at the bottom of FIG. 11, in step S14, the absolute value of the first rotation angle (φ1) corresponding to the second and third notch formation candidate positions (Q2, Q3) is determined not to be greater than or equal to the specified angle (β) and less than or equal to 90°.

[0123] Meanwhile, in step S14, the absolute value of the first rotation angle (φ1) corresponding to the first and fourth notch formation candidate positions (Q1, Q4) is determined to be greater than or equal to the specified angle (β) and less than or equal to 90°.

[0124] And, in the first determination process of step S16, among the first and fourth notch formation candidate positions (Q1, Q4), the first notch formation candidate position (Q1) with a smaller first horizontal rotation angle (θ1) is determined as the notch formation position.

[0125] As shown in FIG. 8, when the notch formation position determination process of step S1 is completed, the grinding control unit (347) controls the grinding unit (31) to cylindrically grind the single crystal (T1) for grinding and process it into a single crystal (T2) for slicing (step S2: cylindrical grinding process).

[0126] Next, the notch formation control unit (348) forms a notch (N) at a notch formation location determined by the first determination process of step S16, the second determination process of step S17, or the third determination process of step S18 (step S3: notch formation process).

[0127] In step S3, the notch forming control unit (348) controls the chuck drive unit (316) to rotate the single crystal (T2) for slicing and stops it in a state where a notch (N) can be formed at a notch forming position by the notch forming unit (33). The notch forming control unit (348) controls the notch forming unit (33) to form a notch (N) at a notch forming position.

[0128] After this, the attachment control unit (473) of the attachment device (4) determines whether the absolute value of the first rotation angle (φ1) corresponding to the notch formation position is greater than or equal to the specified angle (β) (step S4).

[0129] In step S4, if the attachment control unit (473) determines that the absolute value of the first rotation angle (φ1) corresponding to the notch formation position is greater than or equal to the specified angle (β) (step S4: YES), the first attachment process is performed (step S5).

[0130] The first attachment process of step S5 includes the processing of steps S51 to S56 shown in FIG. 13.

[0131] In the first attachment process performed when the absolute value of the first rotation angle (φ1) is greater than or equal to the specified angle (β), the attachment control unit (473) measures the plane orientation (M) of the single crystal (T2) for slicing (Step S51: first plane orientation measurement process).

[0132] In step S51, when a single crystal (T2) for slicing is placed on a pair of rollers (411) of the second rotation processing unit (41), the attachment control unit (473) controls the second rotation processing unit (41) to rotate the single crystal (T2) for slicing so that the notch (N) is positioned at the highest position, i.e., the notch (N) is positioned at the slicing start position (P), as shown in the first drawing from the left at the top of FIG. 14. The attachment control unit (473) controls the second orientation measuring unit (42) to measure the plane orientation (M) of the single crystal (T2) for slicing.

[0133] The attachment control unit (473) controls the second rotation processing unit (41) to rotate the single crystal (T2) for slicing by a first rotation angle (φ1), as shown in the second drawing from the left at the top of FIG. 14 (Step S52: first single crystal rotation process).

[0134] The attachment control unit (473) controls the single crystal bonding processing unit (43) to bond a single crystal (T2) for slicing to a slicing plate (532) (Step S53: first single crystal bonding process).

[0135] The attachment control unit (473) controls the horizontal rotation processing unit (44) to horizontally rotate the slicer (532) by a first horizontal rotation angle (θ1) from a state where the length direction of the work plate (531) and the length direction of the slicer (532) are parallel, as shown in the third drawing from the left at the top of FIG. 14 (Step S54: first single crystal horizontal rotation process).

[0136] The attachment control unit (473) controls the slice sheet adhesive processing unit (45) to attach the slice sheet (532) to the work plate (531) (Step S55: First slice sheet adhesive process).

[0137] The attachment control unit (473) controls the attachment processing unit (46) to attach the work plate (531) of the fixing member (53) to the attachment unit (54) of the slicing device (5) in a reference attachment state, as shown in the fourth drawing from the left (second from the right) at the top of FIG. 14 (Step S56: first fixing member attachment process). At this time, the slice control unit (575) of the slicing device (5) may control the attachment unit (54) so ​​that the work plate (531) is attached.

[0138] By the first attachment process including the above steps S51 to S56, the single crystal (T2) for slicing is attached to the slicing device (5) such that, when viewed from a direction orthogonal to the slicing plane, the rotation angle from the slicing start position (P) is greater than or equal to a specified angle (β), and the plane orientation (M) and the target plane orientation (Mw) coincide.

[0139] In addition, at least one of the processes of rotating the single crystal (T2) for slicing in step S51 and steps S52 to S56 may be performed by an operator.

[0140] As shown in FIG. 8, when the first attachment process of step S5 is completed, the slice control unit (575) of the slice device (5) controls the slice unit (51) and the lifting drive unit (56) to slice the single crystal (T2) for slicing starting from the slice start position (P) (step S6: slice process).

[0141] By the slicing process of step S6, as shown in the fifth drawing from the left (first from the right) at the top of FIG. 14, a plurality of wafers (W) are obtained in which the plane orientation (M) matches the target plane orientation (Mw) and the plane orientation (M) and the notch (N) have a specific relationship.

[0142] Meanwhile, in step S4, if the attachment control unit (473) determines that the absolute value of the first rotation angle (φ1) corresponding to the notch formation position is not greater than or equal to the specified angle (β) (step S4: NO), the second attachment process is performed (step S7).

[0143] The second attachment process of step S7 includes the processing of steps S71 to S78 shown in FIG. 15.

[0144] In the second attachment process performed when the absolute value of the first rotation angle (φ1) is less than the specified angle (β), the attachment control unit (473) rotates the single crystal (T2) for slicing so that the notch (N) is positioned at the slice start position (P), as shown in the first drawing from the left at the bottom of FIG. 14, just like in step S51 of the first attachment process, and measures the plane orientation (M) (step S71: second plane orientation measurement process).

[0145] The attachment control unit (473) controls the second rotation processing unit (41) to rotate the single crystal (T2) for slicing by a second rotation angle (φ2) greater than the first rotation angle (φ1), as shown in the second drawing from the left at the bottom of FIG. 14 (Step S72: second single crystal rotation process).

[0146] The attachment control unit (473) controls the single crystal bonding processing unit (43) to bond a single crystal (T2) for slicing to a slicing plate (532) (Step S73: second single crystal bonding process).

[0147] The attachment control unit (473) controls the horizontal rotation processing unit (44) to horizontally rotate the slicer (532) by a second horizontal rotation angle (θ2) from a state where the length direction of the work plate (531) and the length direction of the slicer (532) are parallel, as shown in the third drawing from the left at the bottom of FIG. 14 (Step S74: second single crystal horizontal rotation process).

[0148] The attachment control unit (473) controls the slice sheet adhesive processing unit (45) to attach the slice sheet (532) to the work plate (531) (Step S75: second slice sheet adhesive process).

[0149] The attachment control unit (473) controls the attachment processing unit (46) to attach the work plate (531) of the fixed member (53) to the attachment unit (54) of the slicing device (5) in a reference attachment state, as shown in the fourth drawing from the left (second from the right) at the bottom of FIG. 14 (Step S76: Second fixed member attachment process). At this time, the slice control unit (575) of the slicing device (5) may control the attachment unit (54) so ​​that the work plate (531) is attached.

[0150] By the above steps S71 to S76, the single crystal (T2) for slicing is attached to the slicing device (5) such that the rotation angle from the slicing start position (P) becomes greater than or equal to the specified angle (β), the horizontal position of the plane orientation (M) and the target plane orientation (Mw) become the same, and the vertical position is different.

[0151] The vertical rotation angle calculation unit (574) calculates a vertical rotation angle (λ) corresponding to the notch formation position determined by the third determination process (Step S77: vertical rotation angle calculation process).

[0152] In step S77, the vertical rotation angle calculation unit (574) calculates the vertical rotation angle (λ) such that the plane orientation (M) and the target plane orientation (Mw) can be aligned when viewed from the direction perpendicular to the plane, as shown in the fifth drawing from the left (first from the right) at the bottom of FIG. 14, when the single crystal (T2) for slicing, in which the notch (N) is located at the slice start position (P), is rotated by a second rotation angle (φ2), then rotated horizontally by a second horizontal rotation angle (θ2), and then rotated vertically around the horizontal axis (E).

[0153] Additionally, the vertical rotation angle calculation process may be performed at any timing after the second horizontal rotation angle calculation process.

[0154] The slice control unit (575) controls the vertical rotation processing unit (55), as shown in the fifth drawing from the left (first from the right) at the bottom of FIG. 14, to vertically rotate the attachment unit (54) by a vertical rotation angle (λ) (Step S78: single crystal vertical rotation process).

[0155] Even in the case where a notch (N) is formed at a notch formation position where the absolute value of the first rotation angle (φ1) is less than the specified angle (β) by the process of step S78, the single crystal (T2) for slicing has a rotation angle from the slicing start position (P) greater than or equal to the specified angle (β) when viewed from a direction orthogonal to the slicing plane, and also has a state in which the plane orientation (M) and the target plane orientation (Mw) coincide.

[0156] In addition, at least one of the processes of rotating the single crystal (T2) for slicing in step S71 and steps S72 to S78 may be performed by an operator.

[0157] As shown in FIG. 8, when the second attachment process of step S7 is completed, the slice control unit (575) performs the slice process of step S6.

[0158] In the slicing process of step S6, as in the case where the slicing process is performed after the first attachment process of step S5, as shown in the fifth drawing from the left (first from the right) at the top of FIG. 14, a plurality of wafers (W) are obtained in which the plane orientation (M) matches the target plane orientation (Mw) and the plane orientation (M) and the notch (N) have a specific relationship.

[0159] By processing steps S1 to S7 above, regardless of the magnitude of the first rotation angle (φ1), a plurality of wafers (W) are obtained in which the surface orientation (M) matches the target surface orientation (Mw) and the surface orientation (M) and the notch (N) have a specific relationship. In the wafers (W) obtained in this way, a curvature orthogonal to the slice direction occurs. Due to this curvature, the slice direction can be estimated, and the positional relationship between the notch (N) and the slice start position (P) can be estimated.

[0160] [Effect of the implementation form]

[0161] The notch formation position determining unit (346) determines a notch formation candidate position (Q) as a notch formation position such that the absolute value of the first rotation angle (φ1) is greater than or equal to the specified angle (β) when slicing a single crystal (T2) for slicing so that the plane orientation (M) matches the target plane orientation (Mw).

[0162] For this reason, damage to the wafer (W) can be suppressed during slicing of the single crystal (T2) for slicing.

[0163] The notch formation position determining unit (346) determines a notch formation candidate position (Q) in which the absolute value of the first rotation angle (φ1) is greater than or equal to the specified angle (β) and less than or equal to 90° as the notch formation position.

[0164] For this reason, the time required for the rotation of the single crystal (T2) for slicing when attaching the single crystal (T2) for slicing to the slicing device (5) can be suppressed.

[0165] [Variation Example]

[0166] Although embodiments of the present invention have been described above with reference to the drawings, the specific configuration is not limited to these embodiments, and various improvements and design changes within the scope of not departing from the gist of the present invention are also included in the present invention.

[0167] A candidate notch formation location (Q) in which the first rotation angle (φ1) exceeds 90° may be determined as the notch formation location.

[0168] Among a plurality of candidate notch formation positions (Q) in which the first rotation angle (φ1) is greater than or equal to the specified angle (β), the candidate notch formation position (Q) in which the first horizontal rotation angle (θ1) is not the smallest may be determined as the notch formation position.

[0169] If the absolute value of the first rotation angle (φ1) corresponding to all notch formation candidate positions (Q) is less than the specified angle (β), the notch formation candidate position (Q) in which the first horizontal rotation angle (θ1) is not the smallest may be determined as the notch formation position.

[0170] If the absolute value of the first rotation angle (φ1) corresponding to all notch formation candidate positions (Q) is less than the specified angle (β), the notch formation position is not determined, and the single crystal (T1) for grinding is not used in the manufacture of the wafer (W).

[0171] The correction amount calculation unit (345) may not calculate the first horizontal rotation angle (θ1) of the said notch formation candidate position (Q) when it is determined that the plane orientation (M) viewed from the direction of the crystal center axis (Ct) matches the target plane orientation (Mw) when the slice single crystal (T2) is rotated by the first rotation angle (φ1) from the state where the said notch formation candidate position (Q) is located at the slice start position (P). When a notch (N) is formed at the said notch formation candidate position (Q), the slice plate (532) to which the slice single crystal (T2) is attached is attached to the work plate (531) in a state where the length direction of the said slice plate (532) and the length direction of the said work plate (531) are parallel, and the slice single crystal (T2) is sliced ​​from the said work plate (531) attached to the slice device (5) in a reference attachment state.

[0172] The notch formation positioning process of Step S1 may be performed after the cylindrical grinding process of Step S2.

[0173] Although a configuration in which the cylindrical grinding device (3), the attachment device (4), and the slicing device (5) each have a control device (34, 47, 57) has been exemplified, a control device that controls the cylindrical grinding device (3), the attachment device (4), and the slicing device (5) collectively may also be formed.

[0174] In the above embodiment, the crystal orientation of the crystal center axis (Ct) is <100> Although a method for manufacturing a wafer (W) using a single crystal (T1) for grinding has been exemplified, the crystal orientation of the crystal center axis (Ct) shown in FIG. 16a <110> A single crystal (T1) for grinding, or, the crystal orientation of the crystal center axis (Ct) shown in FIG. 16b <111> A wafer (W) may be manufactured using a single crystal (T1) for grinding.

[0175] When using the grinding single crystal (T1) shown in FIG. 16a, the outer surface of the grinding single crystal (T1) has a crystal orientation <110> Two crystal axes, namely two notch formation candidate positions (Q) (first notch formation candidate position (Q1) and second notch formation candidate position (Q2)), exist at 180° intervals in the circumferential direction. Then, by the notch formation position determination process shown in FIG. 9, the first notch formation candidate position (Q1) or the second notch formation candidate position (Q2) is determined as a notch formation position.

[0176] When using the grinding single crystal (T1) shown in FIG. 16b, the outer surface of the grinding single crystal (T1) has a crystal orientation <111> There are three crystal axes, namely three notch formation candidate positions (Q) (first notch formation candidate position (Q1), second notch formation candidate position (Q2), and third notch formation candidate position (Q3)), which exist at 120° intervals in the circumferential direction. Then, by the notch formation position determination process shown in FIG. 9, any one of the first to third notch formation candidate positions (Q1 to Q3) is determined as a notch formation position.

[0177] Examples

[0178] Next, embodiments of the present invention will be described. Furthermore, the present invention is not limited to the embodiments.

[0179] As an example, when a notch formation position of a single crystal (T2) for slicing having an arbitrary plane orientation (M) is determined using the method for determining a notch formation position of the present invention or the method for determining a notch formation position of a comparative example, a simulation was performed to determine whether or not a single crystal (T2) for slicing can be sliced ​​so that a plurality of wafers (W) in which the plane orientation (M) matches the target plane orientation (Mw) are obtained while suppressing damage around the notch (N).

[0180] [Simulation Method of Comparative Examples]

[0181] First, the simulation method of the comparative example will be explained.

[0182] In the simulation of the comparative example, various conditions were set as follows.

[0183] · Diameter of single crystal (T2) for slicing: 301 mm

[0184] · Crystal orientation of the crystal center axis (Ct): <100>

[0185] · Target plane bearing (Mw): X = 0.25°, Y = 0.00°

[0186] The X direction representing the target plane orientation (Mw) is the horizontal direction, and the Y direction is the vertical direction.

[0187] In addition, a method for determining the notch formation position of the comparative example was established. The method for determining the notch formation position of the comparative example involves rotating the single crystal (T2) for slicing by processing similarly to step S11 of the above embodiment, determining the first crystal axis measured among a plurality of crystal axes existing in the single crystal (T2) for slicing as the notch formation position, and obtaining the positional relationship between the notch formation position and the plane orientation (M).

[0188] Then, for 2881 single crystals (T2) for slicing in which at least one of the horizontal direction (X direction) and vertical direction (Y direction) values ​​of the plane orientation based on the crystal center axis (Ct) when viewed from the direction of the crystal center axis (Ct), processing based on the method for determining the notch formation position of the comparative example was performed, and the positional relationship between the notch formation position and the plane orientation (M) was obtained.

[0189] In addition, based on the plane orientation (M) and the target plane orientation (Mw), a first rotation angle (φ1) corresponding to the notch formation position was calculated.

[0190] [Simulation method of the example]

[0191] Next, the simulation method of the embodiment will be described.

[0192] In the simulation of the example, the diameter of the single crystal (T2) for slicing, the crystal orientation of the crystal center axis (Ct), and the target plane orientation (Mw) were set to the same values ​​as in the comparative example, and the specified angle (β) was set as follows.

[0193] · Specified angle (β): 45°

[0194] In addition, a method for determining the notch formation position by the first determination process of step S16 or the second determination process of step S17 in the notch formation position determination process of step S1 shown in FIG. 8, that is, the method for determining the notch formation position of the present invention, was set as the method for determining the notch formation position of the embodiment.

[0195] Then, for 2881 single crystals (T2) for slicing identical to the comparative example, processing based on the method for determining the notch formation position of the example was performed, and one notch formation candidate position among a plurality of notch formation candidate positions existing in the single crystal (T2) for slicing was determined as the notch formation position, and a first rotation angle (φ1) corresponding to the notch formation position was calculated.

[0196] [Simulation Results and Discussion]

[0197] A single crystal (T2) for slicing in which the first rotation angle (φ1) corresponding to the notch formation position is greater than or equal to the specified angle (β) is evaluated as an acceptable product, and a single crystal (T2) for slicing in which the angle is less than the specified angle (β) is evaluated as an unacceptable product.

[0198] In the method for determining the notch formation position of the comparative example, the pass rate was 57.7% (number of accepted products: 1,663), whereas in the method for determining the notch formation position of the example, the pass rate was 91.1% (number of accepted products: 2,626).

[0199] In the above respects, it was confirmed that when a notch formation position of a single crystal (T2) for slicing having an arbitrary plane orientation (M) is determined using the method for determining a notch formation position of the present invention, a single crystal (T2) for slicing can be sliced ​​such that a plurality of wafers (W) are obtained in which the plane orientation (M) matches the target plane orientation (Mw) while suppressing damage to the area around the notch (N). Explanation of the symbols

[0200] 1 : Wafer Manufacturing System 4: Attachment device 5: Slicing device 33 : Notch forming part (notch forming device) 344 : Position relationship acquisition unit (notch forming position determining device, notch forming device) 345 : Correction amount calculation unit (notch formation position determining device, notch forming device) 346 : Notch formation position determining unit (notch formation position determining device, notch forming device) 348 : Notch formation control unit (notch forming device) 574 : Vertical rotation angle calculation unit D: Vertical axis E : Horizontal axis M: Surface orientation Mw: Target plane bearing N : Notch P: Slice start position Q: Candidate locations for notch formation Q1~Q4: Candidate locations for the 1st to 4th notch formation T1: Single crystal for grinding T2: Single crystal for slicing W : Wafer β: Defined angle θ1, θ11, θ12: First horizontal rotation angle θ2 : Second horizontal rotation angle λ: Vertical rotation angle φ1: First rotation angle φ2: Second rotation angle

Claims

Claim 1 A method for determining a notch formation position in a single crystal used for manufacturing a plurality of wafers having a notch, comprising: a position relationship acquisition process for acquiring a position relationship between a plurality of notch formation candidate positions specified based on the crystal orientation of the single crystal and the plane orientation of the single crystal; a first rotation angle calculation process for calculating a first rotation angle such that when the single crystal is rotated around the central axis of the single crystal from a state in which the notch formation candidate positions are located at a slice start position, the vertical position of the plane orientation and the target plane orientation when viewed from the direction of the central axis becomes identical; and a determination process for determining the notch formation candidate positions such that the absolute value of the first rotation angle is greater than or equal to a specified angle as the notch formation positions. Claim 2 A method for determining a notch formation position according to claim 1, wherein the specified angle is an acute angle, and the determination process determines the notch formation candidate position, in which the absolute value of the first rotation angle is 90° or less, as the notch formation position. Claim 3 A method for determining a notch formation position according to claim 1, comprising a first horizontal rotation angle calculation process for calculating a first horizontal rotation angle such that when the single crystal rotated by the first rotation angle is horizontally rotated around a vertical axis, the plane orientation when viewed from a direction perpendicular to the slice plane of the single crystal matches the target plane orientation, and the determination process determines the notch formation candidate position having the smallest first horizontal rotation angle as the notch formation position when there are multiple notch formation candidate positions in which the absolute value of the first rotation angle is greater than or equal to the specified angle. Claim 4 A method for forming a notch, comprising a notch forming position determining process for determining the notch forming position by a method for determining the notch forming position described in any one of claims 1 to 3, and a notch forming process for forming the notch at the notch forming position. Claim 5 A method for manufacturing a wafer, comprising: a process of forming a notch in the single crystal by the notch forming method described in paragraph 4; an attachment process of attaching the single crystal to a slicing device such that the plane orientation when viewed from a direction orthogonal to the slicing plane of the single crystal matches the target plane orientation; and a slicing process of manufacturing the plurality of wafers by slicing the single crystal from the slicing start position with the slicing device. Claim 6 The method comprises a notch formation position determination process for determining the notch formation position by a method for determining the notch formation position described in paragraph 3, a notch formation process for forming the notch at the notch formation position, a first attachment process and a second attachment process for attaching the single crystal to a slicing device, and a slicing process for manufacturing the plurality of wafers by slicing the single crystal from the slicing start position with the slicing device, wherein the determination process determines the notch formation candidate position in which the absolute value of the first rotation angle is greater than or equal to the specified angle as the notch formation position when there is no such candidate position in which the absolute value of the first rotation angle is greater than or equal to the specified angle, and when the notch formation candidate position in which the absolute value of the first rotation angle is greater than or equal to the specified angle is determined as the notch formation position, the notch formation process, the first attachment process for attaching the single crystal to the slicing device such that the plane orientation when viewed from a direction orthogonal to the slicing surface coincides with the target plane orientation based on the first rotation angle and the first horizontal rotation angle, and the slicing When a process is performed and the notch formation candidate position, in which the absolute value of the first rotation angle is less than the specified angle, is determined as the notch formation position, when the single crystal in a state where the notch formation position is located at the slice start position is rotated around the central axis, the vertical position of the target plane orientation and the plane orientation when viewed from the direction of the central axis become different, and furthermore, a second rotation angle calculation process for calculating a second rotation angle greater than the specified angle, and when the single crystal rotated by the second rotation angle is horizontally rotated around the vertical axis, the plane orientation and the horizontal position of the target plane orientation when viewed from the direction orthogonal to the slice plane become identical, and furthermore,A method for manufacturing a wafer, comprising: a second horizontal rotation angle calculation process for calculating a second horizontal rotation angle such that the position in the vertical direction is different; a vertical rotation angle calculation process for calculating a vertical rotation angle such that when the single crystal, which has been rotated by the second rotation angle and then horizontally rotated by the second horizontal rotation angle, is vertically rotated around a horizontal axis, the plane orientation when viewed from a direction orthogonal to the slice plane matches the target plane orientation; the notch forming process; the second attachment process for attaching the single crystal to the slice device and then vertically rotating it by the vertical rotation angle, based on the second rotation angle and the second horizontal rotation angle, such that the horizontal position of the plane orientation when viewed from a direction orthogonal to the slice plane and the target plane orientation are the same, and the position in the vertical direction is different; and the slicing process. Claim 7 A notch formation position determining device for determining a notch formation position in a single crystal used for manufacturing a plurality of wafers having a notch, comprising: a position relationship acquiring unit for acquiring a position relationship between a plurality of notch formation candidate positions specified based on the crystal orientation of the single crystal and a plane orientation of the single crystal; a correction amount calculating unit for calculating a first rotation angle such that when the single crystal is rotated around the central axis of the single crystal from a state where the notch formation candidate position is located at a slice start position, the vertical position of the plane orientation and the target plane orientation when viewed from the central axis direction becomes the same; and a notch formation position determining unit for determining the notch formation candidate position such that the absolute value of the first rotation angle is greater than or equal to a specified angle as the notch formation position. Claim 8 A notch forming position determining device according to claim 7, wherein the specified angle is an acute angle, and the notch forming position determining part determines the notch forming candidate position, in which the absolute value of the first rotation angle is 90° or less, as the notch forming position. Claim 9 In claim 7, the correction amount calculation unit calculates a first horizontal rotation angle such that when the single crystal rotated by the first rotation angle is horizontally rotated around a vertical axis, the plane orientation when viewed from a direction perpendicular to the slice plane that is perpendicular to the slice plane of the single crystal matches the target plane orientation, and the notch formation position determination unit determines the notch formation candidate position with the smallest first horizontal rotation angle as the notch formation position when there are multiple notch formation candidate positions in which the absolute value of the first rotation angle is greater than or equal to the specified angle. Claim 10 A notch forming device comprising a notch forming position determining device described in any one of claims 7 to 9, and a notch forming part that forms the notch at the notch forming position. Claim 11 A wafer manufacturing system comprising: a notch forming device described in claim 10; a slicing device for manufacturing a plurality of wafers by slicing the single crystal from the slicing start position; and an attachment device for attaching the single crystal to the slicing device such that the plane orientation when viewed from a direction orthogonal to the slicing plane of the single crystal matches the target plane orientation. Claim 12 The apparatus comprises a notch forming position determining device described in claim 9, a notch forming unit for forming the notch at the notch forming position, a slicing device for manufacturing the plurality of wafers by slicing the single crystal from the slicing start position, an attachment device for attaching the single crystal to the slicing device, and a vertical rotation angle calculation unit. The notch forming position determining unit determines, when there is no notch forming candidate position where the absolute value of the first rotation angle is greater than or equal to the specified angle, the notch forming candidate position where the absolute value of the first rotation angle is less than the specified angle as the notch forming position. When the notch forming candidate position where the absolute value of the first rotation angle is greater than or equal to the specified angle is determined as the notch forming position, the attachment device attaches the single crystal to the slicing device based on the first rotation angle and the first horizontal rotation angle such that the plane orientation when viewed from a direction orthogonal to the slicing plane coincides with the target plane orientation. The slicing device slices the single crystal attached by the attachment device, and the first rotation angle When the notch formation candidate position, whose absolute value is less than the specified angle, is determined as the notch formation position, the correction amount calculation unit calculates a second rotation angle greater than the specified angle, such that when the single crystal in a state where the notch formation position is located at the slice start position is rotated around the central axis, the vertical position of the plane orientation viewed from the direction of the central axis becomes different from the vertical position of the target plane orientation, and also calculates a second rotation angle greater than the specified angle, and when the single crystal rotated by the second rotation angle is horizontally rotated around the vertical axis, the horizontal position of the plane orientation viewed from the direction orthogonal to the slice plane becomes the same from the vertical position of the target plane orientation, and also calculates a second horizontal rotation angle such that the vertical position becomes different; and the vertical rotation angle calculation unit,A wafer manufacturing system comprising: calculating a vertical rotation angle such that when the single crystal, which has been rotated by the second rotation angle and then horizontally rotated by the second horizontal rotation angle, is vertically rotated around a horizontal axis, the plane orientation when viewed from a direction orthogonal to the slice plane coincides with the target plane orientation; and, based on the second rotation angle and the second horizontal rotation angle, the attachment device attaches the single crystal to the slicing device such that the horizontal position of the plane orientation when viewed from a direction orthogonal to the slice plane and the target plane orientation are identical, and the vertical position is different; and, the slicing device vertically rotates the single crystal attached by the attachment device by the vertical rotation angle and then slices it.

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