JP2018192750A - Method for producing wafer, and pressing fixture - Google Patents

Abstract

To prevent the falling and dropping of a plurality of wafers formed after cutting of a single crystal.SOLUTION: Provided is a method for producing wafers of producing wafers W by cutting a columnar single crystal C, comprising: a step where a part of the circumferential face Sc of the single crystal C is adhered to a pedestal 7 with an adhesive 10; a step where the single crystal C adhered to the pedestal 7 is cut by a cutting apparatus 1 to form the plurality of wafers W adhered to the pedestal 7 and also arranged at intervals; a step where, using pressing parts 14 of pressing a part of the respective circumferential faces Sc of the plurality of wafers W, the circumferential faces Sc are held with either or both of a space between each pressing part 14 and the pedestal 7 and a space between the pressing parts 14 each other, and pressing is performed to fix the relative positions of the plurality of the wafers W; and a step where the plurality of wafers W adhered to the pedestal 7 are peeled from the pedestal 7.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wafer manufacturing method and a holding jig.

  The wafer is manufactured by cutting a single crystal. Conventionally, a method of cutting a single crystal to form a wafer is known. For example, in the cutting method by the wire saw apparatus described in Patent Document 1, the spindle has three spindle rollers, and grooves are formed on the outer circumference of the spindle rollers at a pitch according to the target wafer thickness. A wire saw device in which a wire is wound along a groove of a main shaft roller is used. Then, while rotating the spindle roller to run the wire, by operating the main body table to which the plurality of single crystals are fixed and pressing the single crystals against the wire, the plurality of single crystals are cut at the same time, and a large number of wafers are obtained. Form. In this processing method, a processing liquid (also referred to as slurry) containing abrasive grains between the workpiece and the wire while pressing the workpiece against a plurality of ultrafine wire rows parallel at a constant pitch and feeding the wire in the linear direction. ), Or a method of polishing and cutting a workpiece while feeding a wire in which diamond is fixed by electrodeposition or adhesive in the linear direction, and a large number of wafers having a constant thickness. Are formed at the same time.

  In the conventional procedure for cutting a single crystal to form a wafer, first, a base on which the single crystal is fixed with an adhesive is fixed to a slicing base of a wire saw device, and this slicing base is placed on the wire saw device. Next, the cutting process by the wire saw device is started, and the single crystal is cut by moving the slice table to the processing position. In this cutting, the base is cut to about 5 mm. The wafer formed by this cutting has a thickness of about 0.2 mm to 2 mm, and its circumferential surface is partially held on the pedestal only by an adhesive. Then, in this state, the slicing table on which the wafer is held via the pedestal is taken out from the wire saw device, and a peeling operation is performed to peel off the adhesion between the pedestal and the wafer, and the wafers are individually taken out.

JP 2001-001248 A

  In the case of the above method, the wafer formed by cutting the single crystal by the wire saw device is detached from the wire saw device while the circumferential surface of the wafer is partially held only by the adhesive. And transported to the place where the above-described peeling operation is performed. This transportation is performed by a transportation vehicle such as a lifter. In such transport from the removal of the slicing table to the place where the peeling operation is performed, the wafer may fall down and be damaged due to vibration or impact. Further, when the slicing table is taken out from the wire saw device as described above, the wafer may fall and be damaged. Further, in the above-described peeling operation, the adhesive force of the adhesive is reduced and the wafer is removed from the pedestal and collected, so that the holding force of the wafer by the pedestal is further reduced and the wafer is easily collapsed and damaged.

  In particular, recently, due to the thinning and large diameter of the wafer, the bonding area for holding the wafer on the pedestal has been reduced, and the above-described breakage due to the falling of the wafer has become prominent. For example, in the case of a product having a wafer thickness of 0.6 mm or less and a wafer diameter of 8 inches or more, the wafer collapses even with a small vibration or impact, causing deterioration in productivity.

  Therefore, the present invention has been made in view of the above situation, and an object of the present invention is to provide a wafer manufacturing method and a holding jig for preventing a plurality of wafers formed from falling and falling after cutting a single crystal. To do.

  In order to solve the above-described problems, the present inventor has intensively studied. As a result, a plurality of wafers formed by the above-described single crystal cutting process are fixed in a predetermined manner. As a result, it has been found that the wafer can be prevented from falling and falling. The present invention has been completed based on such technical findings.

  That is, according to the first aspect of the present invention, there is provided a method for manufacturing a wafer by cutting a columnar single crystal, wherein a part of a circumferential surface of the single crystal is bonded to a pedestal with an adhesive; Cutting a single crystal bonded to the pedestal with a cutting device to form a plurality of wafers bonded to the pedestal and arranged at intervals, and pressing a part of the circumferential surface of each of the plurality of wafers Using this unit, the relative position between multiple wafers is fixed by sandwiching and pressing the circumferential surface between one or both of the holding part and the pedestal and between the holding parts, and bonded to the pedestal. Peeling the plurality of wafers from the pedestal, a method for manufacturing a wafer is provided.

  Moreover, according to the 2nd aspect of this invention, the manufacturing method of a wafer including peeling in the state which the press part pinched | interposed and pressed the circumferential surface in the 1st aspect is provided.

  According to the third aspect of the present invention, in the first or second aspect, the fixing is performed in a state where a plurality of wafers bonded to the base and arranged at intervals are attached to the cutting apparatus. A method for manufacturing a wafer is provided.

  According to the fourth aspect of the present invention, a part of the circumferential surface of each of a plurality of wafers arranged at intervals is formed by cutting a columnar single crystal fixed to a pedestal. There is provided a pressing jig including a pressing portion capable of fixing a relative position between a plurality of wafers.

  According to the fifth aspect of the present invention, in the fourth aspect, the pressing portion includes a first pressing portion that sandwiches the circumferential surface between itself and the pedestal and presses a part of the circumferential surface. A holding jig is provided.

  Further, according to the sixth aspect of the present invention, in the fourth or fifth aspect, the pressing portion is formed by sandwiching the circumferential surface from the direction orthogonal to the central axis direction of the single crystal and the opposing direction of the pedestal. A pressing jig including a pair of second pressing portions that presses a part of the peripheral surface is provided.

  According to the seventh aspect of the present invention, in the sixth aspect, each of the pair of second pressing portions intersects with the central axis of the single crystal and is orthogonal to each other at a position in contact with a part of the circumferential surface. There is provided a pressing jig that is set on the pedestal side with respect to a reference line in the direction in which it is performed.

  According to an eighth aspect of the present invention, in any one of the fourth to seventh aspects, a pressing jig is provided in which a portion that contacts the circumferential surface is an elastic body.

  According to the ninth aspect of the present invention, in any one of the fourth to eighth aspects, the pressing jig comprising the end surface pressing portions that are in contact with and support the end surfaces of the wafers at both ends of the plurality of wafers. Provided.

  According to a tenth aspect of the present invention, in any one of the fourth to ninth aspects, a pressing jig is provided that includes an attachment portion that can be attached to a cutting device for cutting a single crystal.

  According to the wafer manufacturing method and the pressing jig of the present invention, the relative position between a plurality of wafers formed by cutting a single crystal is fixed, so that the falling and falling of the wafer can be suppressed.

  In addition, in the wafer manufacturing method, when the pressing portion includes the pressing while sandwiching the circumferential surface, the wafer can be prevented from falling when the wafer is released from the pedestal. Further, when the fixing includes performing a plurality of wafers bonded to the pedestal and arranged at intervals with the wafers attached to the cutting apparatus, it is possible to prevent the wafer from falling when it is taken out from the cutting apparatus.

It is a flowchart which shows the manufacturing method of the wafer which concerns on embodiment. It is the schematic of a wire saw apparatus. It is a perspective view which shows the single crystal adhere | attached on the base. It is a perspective view which shows the state which installed the single crystal in the slice stand through the base. (A) And (B) is a perspective view which shows the operation | movement which cut | disconnects a single crystal with a wire saw apparatus. It is a perspective view which shows the state at the time of use of the holding jig of this embodiment. (A) And (B) is a figure which shows a pressing jig, (A) is a perspective view, (B) is the arrow view seen from the I direction shown to (A). It is a disassembled perspective view of a holding jig. It is a perspective view which shows the 1st example of a pressing jig. It is a perspective view which shows the 2nd example of a pressing jig. It is a figure explaining a peeling process. It is a figure explaining the peeling process following FIG.

  In the following description, the XYZ orthogonal coordinate system shown in FIG. In this XYZ orthogonal coordinate system, the X direction and the Y direction are horizontal directions, and the Z direction is a vertical direction perpendicular to the X direction and the Y direction. In each direction, the same side as the tip of the arrow is appropriately referred to as a + side (eg, + Z side), and the opposite side of the arrow is referred to as a − side (eg, −Z side). For example, in the vertical direction (Z direction), the upper side is the + Z side and the lower side is the -Z side. In each drawing, a part or the whole is schematically described as appropriate, and the scale is changed and described.

[Embodiment]
Embodiments will be described. FIG. 1 is a flowchart showing a wafer manufacturing method according to the first embodiment. The wafer manufacturing method of the present embodiment (hereinafter simply referred to as “wafer manufacturing method”) is a method of manufacturing a wafer by cutting a columnar single crystal. As shown in FIG. 1, the wafer manufacturing method includes an adhesion process (step S1), a cutting process (step S2), a fixing process (step S3), and a peeling process (step S4). In the present embodiment, the “wafer” means a disk-shaped plate formed by cutting a columnar single crystal.

  First, a single crystal cutting apparatus used in a wafer manufacturing method will be described. FIG. 2 is a schematic view of a wire saw apparatus used in the wafer manufacturing method. The cutting device used in the wafer manufacturing method is, for example, a known wire saw device. In the present embodiment, the single crystal cutting apparatus used in the wafer manufacturing method will be described as a wire saw apparatus shown in FIG. 2, but is an example, and the cutting apparatus can manufacture the wafer W by cutting the single crystal C. Other cutting devices may be used. For example, the cutting device may be a cutting device such as a blade or a wire electric discharge machine. Moreover, the wire saw apparatus 1 shown in FIG. 2 is an example, and the wire saw apparatus of another aspect may be sufficient.

  The wire saw device 1 shown in FIG. 2 is a so-called multi-wire saw device. The wire saw device 1 moves a wire row 4 composed of a plurality of wires 3 stretched between three sets of rotating rollers 2a to 2c at a predetermined interval relative to a columnar single crystal C. Then, while pressing the single crystal C in the cutting direction (Z direction in the figure), each wire 3 (wire row 4) travels in one direction or in a reciprocating direction to perform cutting processing. When the single crystal C is cut using such a multi-wire saw device, more parts of the single crystal C can be cut by a single cutting operation, so that the single crystal C can be cut efficiently. .

  In the cutting method using the wire saw device 1, a method of supplying a processing liquid containing abrasive grains to the portion where the wire 3 and the single crystal C are in contact (free abrasive grain method), and a method in which the abrasive grains are fixed to the wire 3 in advance. Although there is a method to be used (fixed abrasive method), any of the above-described cutting methods can be used in the wafer manufacturing method of the present embodiment.

  The wire saw device 1 is equipped with a slicing base 6 on which a single crystal C is fixed, and the single slicing is performed in the wire array 4 by moving the mounted slicing base 6 relative to the wire array 4 in the vertical direction. Cut C. The single crystal C is fixed to the slicing base 6 via a base 7 (slice bed). The pedestal 7 has a plate shape, and the upper surface and the lower surface are horizontal surfaces (see FIG. 4). Single crystal C is fixed to one horizontal surface (lower surface in the present embodiment) of pedestal 7, and the other horizontal surface (upper surface in the present embodiment) of pedestal 7 is fixed to slice base 6 (see FIGS. 1 and 4). ). The slicing base 6 is mounted on the mounting portion 8 of the wire saw device 1. The mounting portion 8 can adjust the position and angle of the mounted slicing base 6, and can position the single crystal C by this adjustment. The slicing base 6 can be detached from the mounting portion 8. Thereby, the slicing base 6 can be detached from the wire saw device 1 and the single crystal C can be fixed to the slicing base 6 via the pedestal 7, and the single crystal C is formed by cutting the single crystal C with the wire saw device 1. The wafer W (see FIG. 5B) can be detached from the wire saw device 1 together with the slicing base 6 and the base 7.

  Next, each step of the wafer manufacturing method will be described in detail. Note that the following description of each process is an example, and does not limit the method of manufacturing a wafer of this embodiment. FIG. 3 is a perspective view showing a single crystal bonded to a pedestal. In the bonding step of step S <b> 1 shown in FIG. 1, a part of the circumferential surface Sc of the single crystal C is bonded to the pedestal 7 with the adhesive 10 as shown in FIG. 3. The shape of the single crystal C is generally cylindrical, but the single crystal C has an orientation flat (also referred to as an orientation flat) obtained by grinding a part of the circumferential surface Sc into a flat shape for identification. In some cases, a notch with a part cut away is processed. In the present specification, a shape obtained by processing an orientation flat or a notch on a columnar single crystal C is included in the columnar shape.

  In the present embodiment, the single crystal C is placed on the slicing table 6 via the pedestal 7 and cut to a part of the pedestal 7 together with the single crystal C in the next cutting step (see FIG. 5B). Thereby, the single crystal C can be cut | disconnected reliably. For this reason, it is preferable that the material of the base 7 is a material that can be cut by the wire saw device 1 (cutting device) such as resin or glass. The thickness of the pedestal 7 can be arbitrarily set. However, when a part of the pedestal 7 is cut by the wire saw device 1 as described above, the depth is about 5 mm, so the thickness of the pedestal 7 is 10 mm or more. Is more preferable, and is more preferably around 20 mm. The base 7 and the single crystal C are bonded and fixed by the adhesive 10. The adhesive 10 is not particularly limited. However, since the wafer W formed after cutting the single crystal C is peeled off from the base 7 in a later step, it is preferable to use an easily peelable adhesive. Examples of such an adhesive 10 include an epoxy adhesive. Further, when the single crystal C has an orientation flat, the base 7 and the single crystal C may be bonded by aligning the orientation flat surface with the base 7. When the orientation flat surface is bonded to the pedestal 7, the bonding area is larger than that when the circumferential surface Sc is bonded, so that the above bonding can be strengthened.

  Next, in the cutting process of step S2 shown in FIG. 1, the single crystal C bonded to the pedestal 7 is cut to form a plurality of wafers W bonded to the pedestal 7 and arranged at intervals. FIG. 4 is a perspective view showing a state in which a single crystal is placed on a slicing table via a pedestal. 5A and 5B are perspective views showing an operation of cutting a single crystal with a wire saw device.

  In this cutting process, first, as shown in FIG. 4, the base 7 to which the single crystal C is bonded is fixed to the slice base 6 in step S <b> 1. In this embodiment, the base 7 to which the single crystal C is bonded is fixed to the lower surface of the slicing table 6 with an adhesive (not shown) on the surface to which the single crystal C is not bonded. The single crystal C and the pedestal 7 may be bonded by bonding the pedestal 7 to the slicing table 6 and then bonding the single crystal C to the pedestal 7. The adhesive is not particularly limited and can be arbitrarily set. However, it is preferable to use the above-described easily peelable epoxy adhesive used for bonding the base 7 and the single crystal C. In addition, in this embodiment, the example in which the single crystal C is installed in the wire saw device 1 facing downward is shown, but the method of installing the single crystal C in the cutting device is appropriately set according to the type of the cutting device. Is set.

  Subsequently, the slicing base 6 on which the single crystal C is fixed via the pedestal 7 is mounted on a mounting portion (not shown) of the wire saw device 1 to cut the single crystal C. In the wire saw device 1 of the present embodiment, the wire row 4 and the single crystal C are relatively moved as shown in FIGS. 5A to 5B, and the single crystal C is wired at the processing position. While pressing the cutting direction (-Z direction in the figure) against the row 4, the wire row 4 is moved in one direction or the reciprocating direction to perform cutting. For example, by moving the slice table 6 on which the single crystal C is fixed downward by the wire saw device 1, a plurality of wires 3 parallel to the Y direction are pressed against the wire row 4 arranged at equal intervals in the X direction. A single crystal C is cut. Thus, the single crystal C bonded to the pedestal 7 is cut in the Z direction, and a plurality of wafers W bonded to the pedestal 7 and arranged in the X direction at intervals are formed. At this time, as shown in FIG. 5B, the single crystal C and a part (lower surface) of the base 7 are cut to a depth of about 5 mm. Thereby, the single crystal C can be cut | disconnected reliably. The thickness (X direction) of the wafer W is not particularly limited, but is set to 0.2 mm to 1.0 mm, for example. The thickness of the wafer W and the interval with the wafer W can be set to a predetermined thickness and a predetermined interval by adjusting the diameter and pitch of the wires 3, respectively.

  Next, in the fixing step of step S3 shown in FIG. 1, the relative positions between the plurality of wafers W formed in step S2 are fixed. In the wafer W formed in the previous process, a part of the circumferential surface Sc of the wafer W is bonded to the pedestal 7 with the adhesive 10. For this reason, as described above, the wafer W easily falls down even with a small vibration or impact. In particular, due to the thinning and large diameter of the wafer W, the bonding area for holding the wafer W by the pedestal 7 is reduced, and the above-described breakage due to the falling of the wafer W is likely to occur. For example, products having a wafer W thickness of 0.6 mm or less and a wafer diameter of 8 inches or more are prominent. Therefore, in the manufacturing method of the present wafer, the relative position between the plurality of wafers W is fixed in the main fixing step, and the damage due to the falling of the wafer W is suppressed.

  In the main fixing step, the relative positions between the plurality of wafers W are fixed using the holding jig Z of the present embodiment. First, the holding jig Z will be described. FIG. 6 is a perspective view showing a state when the pressing jig of the present embodiment is used. FIGS. 7A and 7B are views showing the pressing jig, where FIG. 7A is a perspective view, and FIG. 7B is an arrow view seen from the I direction shown in FIG. FIG. 8 is an exploded perspective view of the pressing jig.

  As shown in FIGS. 6 to 8, the holding jig Z of the present embodiment includes a mounting portion 12, an end surface pressing portion 13, and a pressing portion 14. As shown in FIG. 6, the attachment portion 12 is formed to be attachable to the slicing base 6 of the wire saw device 1 that cuts the single crystal C. The attachment portion 12 is provided on the outside (+ X side and −X side) of the plurality of wafers W. When the attachment portion 12 is provided outside the wafer W, the attachment portion 12 can be installed without interfering with the plurality of wafers W.

  As shown in FIG. 7, each attachment portion 12 includes a clamp portion 12 a that sandwiches the slice table 6. The clamp portion 12a is formed to be movable in the + Y direction and the −Y direction by a screw fastening member 19 (see FIG. 8), and can sandwich the slice table 6 from the Y direction. The holding jig Z is attached to the slicing base 6 of the wire saw device 1 by sandwiching the lower part of the slicing base 6 from the Y direction with the clamp portions 12 a of the mounting portions 12. Thereby, the end surface pressing part 13 and the pressing part 14 are fixed to the wire saw device 1. When the holding jig Z includes the attachment portion 12, the relative position between the wafers W can be fixed in a state of being attached to the wire saw device 1, so that the collapse of the wafer W that occurs when taking out from the wire saw device 1 is suppressed. can do.

  The end surface pressing portions 13 are provided on the + X side and the −X side of the plurality of wafers W, and contact and support the end surfaces (+ X side surface, −X side surface) of the wafers W at both ends of the plurality of wafers W. . When the pressing jig Z includes the end surface pressing portion 13, the falling of the wafers W at both ends of the plurality of wafers W can be suppressed.

  The end surface pressing portion 13 is provided with an elastic body 16 at a portion in contact with the wafer W. In this case, damage to the wafer W that occurs when the relative position between the wafers W is fixed can be suppressed. The elastic body 16 is preferably a soft rubber such as silicon.

  Each end surface pressing part 13 is connected to the attachment part 12 by the connection part 17a and the connection part 17b. The connection portion 17 a has a shape extending in the facing direction (Z direction) of the base 7, and one end portion (the end portion on the + Z side) is fixed to the attachment portion 12. The connection portion 17 b has a shape extending in the central axis AX direction (X direction) of the single crystal C, one end portion is connected to the connection portion 17 a, and the other end portion is fixed to the attachment portion 12. The connection portion 17b can move in a direction close to the base 7 and a direction away from the base 7 (Z direction) with respect to the connection portion 17a, and can be fixed at a predetermined position. The fixing mechanism A at the predetermined position is a mechanism for fixing using a fastening member 19 such as a screw. In addition, the connection portion 17b is capable of moving the end surface pressing portion 13 in a direction approaching the wafer W and a direction away from the wafer W (X direction) with respect to the connection portion 17a (attachment portion 12). Connect and fix in place. The fixing mechanism B at a predetermined position is a mechanism for fixing using a fastening member 19 such as a screw.

  With the above configuration, each end surface pressing portion 13 can adjust the position of the portion that contacts the wafer W and the strength of contact with the wafer W. Each end surface pressing portion 13 is adjusted to a strength with which the wafer W is brought into contact with the wafer W to such an extent that the wafers W at both ends do not fall down. As described above, when the position of the portion where the end surface pressing portion 13 is in contact with the wafer W can be adjusted, both ends of the plurality of wafers W can be effectively supported. Further, when the strength with which the end face pressing portion 13 is brought into contact with the wafer W can be adjusted, damage to the wafer W that occurs when the wafer W is fixed can be suppressed.

  The pressing part 14 includes a first pressing part 14a and a second pressing part 14b. The first pressing unit 14a sandwiches the circumferential surface Sc of the wafer W between itself (the first pressing unit 14a) and the pedestal 7 and pushes a part of the circumferential surface Sc. The first pressing portion 14a is an L-shaped member. The first pressing portion 14a has a shape in which a portion in contact with the circumferential surface Sc is disposed on the side facing the pedestal 7 and extends in the central axis direction (X direction) of the single crystal C, and the circumferential surface Sc is disposed on the pedestal. 7 is sandwiched from the side facing (7 side) and a part of the circumferential surface Sc is pushed in the direction of the central axis AX of the single crystal C. When such a first pressing portion 14a is provided, the relative position between the wafers W can be fixed by the single pressing member 14a. Therefore, the relative position between the wafers W can be fixed with a simple configuration.

  Further, the first pressing portion 14 a is provided with the elastic body 20 at a portion in contact with the wafer W. As a result, damage to the wafer W that occurs when the relative position between the wafers W is fixed can be suppressed, and a portion that holds the wafer W sinks to the elastic body 20 side. The elastic body 20 enters the (space) portion, and the interval between the wafers W can be maintained. For this reason, the fall of the wafer W can be suppressed more effectively than when the wafer W is pressed by a flat plate. The elastic body 20 is preferably a soft rubber such as silicon.

  The first pressing portion 14a moves in a direction in which one end portion of the L-shaped member approaches the pedestal 7 and in a direction away from the pedestal 7 (+ Z direction, -Z direction) with respect to the end surface pressing portion 13. It can be fixed at a predetermined position. The fixing mechanism C at the predetermined position is a mechanism for fixing the first pressing portion 14 a to the end surface pressing portion 13 using a fastening member 19 such as a screw. As a result, the first pressing portion 14a has a direction in which a portion in contact with the circumferential surface Sc approaches the wafer W to which the pressing jig Z is mounted along the facing direction (Z direction) of the base 7 and It can be moved in the direction of separation (+ Z direction, −Z direction) and can be fixed at a predetermined position, and the strength of contact with the wafer W can be adjusted. The first pressing portion 14a is adjusted so as to press a part of the circumferential surface Sc to the extent that the interval between the wafers W is maintained. As described above, when the strength with which the first pressing portion 14a is brought into contact with the wafer W can be adjusted, the relative position between the wafers W can be more reliably fixed.

  The second pressing portion 14b is referred to as a direction (hereinafter referred to as a “second direction”) orthogonal to the central axis direction (X direction) of the single crystal C and the facing direction of the pedestal 7 (hereinafter referred to as “first direction”; Z direction). (+ Y direction, -Y direction), and presses a part of the circumferential surface Sc while sandwiching the circumferential surface Sc. The second pressing portion 14b is an L-shaped member configured as a pair. Each of the pair of second pressing portions 14b has a shape in which a portion in contact with the circumferential surface Sc extends in the central axis direction (X direction) of the single crystal C, and is disposed on the + Y side and the −Y side of the single crystal C. Is done. The pair of second pressing portions 14b sandwich the circumferential surface Sc from the Y direction and push a part of the circumferential surface Sc in the direction of the central axis AX of the single crystal C. When the second pressing portion 14b is provided, the relative position between the wafers W can be more reliably fixed.

  Each second pressing portion 14 b is provided with an elastic body 22 at a portion in contact with the wafer W. In this case, damage to the wafer W that occurs when fixing the relative position between the wafers W can be suppressed, and the portion that holds the wafer W sinks to the elastic body 22 side, and conversely, the interval (space) between the wafers W The elastic body 22 enters the portion, and the interval between the wafers W can be maintained. For this reason, the fall of the wafer W can be suppressed more effectively than the case where it is pressed by a flat plate. The elastic body 22 is preferably a soft rubber such as silicon.

  Each of the second pressing portions 14b has a direction in which one end portion of the L-shaped member is close to the wafer W on which the pressing jig Z is mounted along the second direction with respect to the end surface pressing portion 13. The holding jig Z can be moved in a direction (+ Y direction, −Y direction) away from the wafer W to be mounted, and can be fixed at a predetermined position. The fixing mechanism D at a predetermined position is a mechanism for fixing each second pressing portion 14b to the end surface pressing portion 13 using a fastening member 19 such as a screw. Accordingly, each second pressing portion 14b has a portion in contact with the circumferential surface Sc approaching and separating from the wafer W to which the pressing jig Z is attached along the second direction ( + Y direction and −Y direction) and can be fixed at a predetermined position, and the strength of contact with the wafer W can be adjusted. The second pressing portion 14b is adjusted so as to push a part of the circumferential surface Sc to the extent that the interval between the wafers W is maintained. As described above, when the strength with which the second pressing portion 14b is brought into contact with the wafer W can be adjusted, the relative position between the wafers W can be more reliably fixed.

  Further, as shown in FIG. 7B, each of the pair of second pressing portions 14b intersects with the central axis AX (X direction) of the single crystal C at a position where it contacts a part of the circumferential surface Sc. It is set on the pedestal 7 side with respect to a reference line L in a direction (Y direction) orthogonal to the facing direction (Z direction) of the pedestal 7. In this case, when the wafer W is peeled from the pedestal 7, the upper part from the center of the wafer W can be opened, so that the wafer W can be easily taken out from the pedestal 7.

  Each part of the holding jig Z is fixed by the fastening member 19 such as a screw as described above. As shown in FIG. 8, the holding jig Z can be disassembled individually. Thereby, in the next peeling process, the wafer W can be peeled from the pedestal 7 in a state in which a part of the pressing portion 14 is removed and the pressing portion 14 sandwiches and presses the circumferential surface Sc. Further, as a result, the pressing jig Z can be easily manufactured as compared with the case where it is integrally formed, and can be stored compactly when not in use. Each part of the holding jig Z shown in FIG. 8 is assembled by adjusting the size of the single crystal C, the strength to be brought into contact with the plurality of wafers W, etc. during use shown in FIG.

  The configuration of the holding jig Z described above is an example, and other configurations may be used. The holding jig Z includes a holding unit that sandwiches the circumferential surface Sc of the wafer W and presses a part of the circumferential surface Sc, and the wafer is interposed between the holding unit and the base 7 and between one or both of the holding units. Any configuration may be used as long as the relative positions of the plurality of wafers W are fixed by sandwiching and pressing the circumferential surface Sc of W. FIG. 9 is a perspective view showing a first example of the holding jig Z. FIG. FIG. 10 is a perspective view showing a second example of the holding jig Z. FIG. For example, as shown in FIG. 9, the holding jig Z may not include the second holding portion 14 b. Moreover, the holding jig Z does not need to be provided with the 1st holding | suppressing part 14a, as shown in FIG. Moreover, the attachment part 12 may be one instead of a pair. Further, whether or not the mounting portion 12 is provided is arbitrary. Moreover, the end surface pressing part 13 may be one instead of a pair. Further, whether or not the end surface pressing portion 13 is provided is arbitrary. When the end surface pressing portion 13 is not provided, the pressing portion 14 (first pressing portion 14a, second pressing portion 14b) is supported by another member.

  A fixing process using the holding jig Z will be described. In the main fixing step, the pressing portion 14 (first pressing portion 14a) is pressed using the pressing portion 14 (first pressing portion 14a, second pressing portion 14b) that presses a part of the circumferential surface Sc of each of the plurality of wafers W. ) And the pedestal 7 and one or both of the pressing parts 14 (a pair of second pressing parts 14b) sandwiching and pressing the circumferential surface Sc, the relative positions between the plurality of wafers W are fixed. To do. In the fixing step, the circumferential surface Sc may be sandwiched and pressed by the first pressing portion 14a and the pedestal 7, or the circumferential surface Sc may be sandwiched and pressed by the second pressing portion 14b. Both the first pressing portion 14a and the base 7 and the pair of second pressing portions 14b by using the first pressing portion 14a and the second pressing portion 14b that press a part of the respective circumferential surface Sc. It is preferable to fix the relative position between the plurality of wafers W by sandwiching and pressing the circumferential surface Sc. In this case, the relative position between the plurality of wafers W can be fixed more reliably. The fixing step is preferably performed in a state where a plurality of wafers W that are bonded to the base 7 and are arranged at intervals are attached to the wire saw device 1. Thereby, the fall of the wafer W produced when taking out from the wire saw apparatus 1 can be suppressed.

  Next, in the peeling process of step S <b> 4 shown in FIG. 1, the plurality of wafers W bonded to the base 7 are peeled from the base 7. 11 and 12 are explanatory views of the peeling process. In this peeling process, the slicing base 6 to which the holding jig Z is attached is removed in the wire saw device 1, and the adhesive 10 between the wafer W and the base 7 of the slicing base 6 and the adhesive between the base 7 and the slicing base 6 are used. 10 is a step of separating the wafers 10 and taking out the wafers W individually.

  As described above, the slicing base 6 needs to be removed from the wire saw device 1, transported to the peeling tank T, and immersed in the peeling liquid LQ of the peeling tank T. During this transportation and movement, the wafer W is likely to fall down due to vibration or impact. When the slicing base 6 is removed from the wire saw apparatus 1, in the case of the method of pressing the slicing base 6 against the wire 3 from above, the wafer W formed by cutting the single crystal C, as shown in FIG. 6 is the upper side and the wafer W is the lower side. When transporting, as shown in FIG. 11, it is necessary to rotate it 180 degrees, and at this time, the wafer W is particularly likely to fall down. Therefore, it is preferable to attach the holding jig Z in the wire saw device 1 before the slicing base 6 is removed from the wire saw device 1 after the above-described cutting, thereby preventing the above-described collapse.

  The peeling of the adhesive 10 depends on the type of the adhesive, but for example, in the case of an epoxy adhesive, it can be peeled by applying a temperature of 60 ° C to 100 ° C. In this case, as shown in FIG. 12, the slicing stage 6 to which the single crystal C is fixed via the pedestal 7 is immersed in the high-temperature peeling liquid LQ in the peeling tank T. In the peeling step, the slicing base 6 is immersed in the high temperature peeling solution LQ in the peeling tank T for a predetermined time. By dipping for a predetermined time, the adhesive force of the adhesive 10 is reduced and the wafer W is recovered. At this time, since the adhesive force of the adhesive 10 is reduced, the holding force of the wafer W is further reduced, and the wafer W is more likely to fall down. For this reason, it is preferable to perform peeling in a state in which the pressing portion 14 sandwiches and presses the circumferential surface Sc of the wafer W while the pressing jig Z is installed. The wafer W may be taken out in the stripping solution LQ or may be taken out of the stripping solution LQ after being immersed in the stripping solution LQ.

  When the wafer W is taken out (peeled), a part of the pressing portion 14 is removed. For example, when using the 1st press part 14a and the 2nd press part 14b, the 1st press part 14a is removed. As a result, the wafer W is released from the side where the wafer W is taken out while being fixed by the second pressing portion 14b. Thereby, it can peel in the state which the pressing part 14 pinched | interposed and pressed the circumferential surface Sc, and the fall of the wafer W at the time of peeling the wafer W from the base 7 can be suppressed. At this time, the strength with which the second pressing portion 14b fixes the wafer W may be appropriately adjusted.

  In the present embodiment, as described above, the positions at which the second pressing portions 14b are in contact with a part of the circumferential surface Sc intersect with the central axis AX of the single crystal C and are perpendicular to each other (Y direction). ) With respect to the reference line L (see FIG. 7B). As a result, the upper part of the wafer W can be opened wider than the center of the wafer W, so that the wafer W can be easily taken out from the base 7. In this case, it is preferable that the wafer W can be easily taken out from the lower side without adjusting the fixing strength of the pressing portion 14 and can be taken out. The wafer W may be taken out by removing one of the second pressing portions 14b when a part of the pressing portion 14 is removed.

  Examples of the present invention will be specifically described below.

  A single crystal C of lithium tantalate (hereinafter referred to as LT) having a size of φ150 mm and a length of 100 mm was prepared. The pedestal 7 having a thickness of 20 mm was fixed to the slicing base 6 with an epoxy adhesive. And the single crystal C was fixed to this base 7 with the epoxy-type adhesive agent. Single crystal C was aligned with the mounting surface of pedestal 7 and fixed with the above-mentioned adhesive.

  Next, the slicing base 6 on which the single crystal C was fixed was attached to the wire saw apparatus 1, the single crystal C was cut, and a plurality of wafers W adhered to the base 7 and arranged at intervals were formed. In this cutting, the thickness of the wafer W was 0.6 mm, and the pitch between the wafers W was 0.85 mm. After the cutting, the holding jig Z was attached to the slicing base 6. The holding jig Z was the same as that shown in FIG. In addition, the part which contacts the 1st press part 14a, the 2nd press part 14b, the end surface press part 13, and a wafer was made into the silicon rubber. Next, the slicing base 6 on which the holding jig Z is installed is removed from the wire saw device 1 and transported by a lifter. As shown in FIG. 12, the slicing base 6 is immersed in the high-temperature stripping solution LQ in the stripping tank T. Then, the adhesive was peeled off. Thereafter, the first holding portion 14a of the holding jig Z is removed in the peeling tank T, the wafers W are moved one by one in the direction facing the pedestal 7 and removed from the pedestal 7, and a carrier case for accommodating the wafer W is obtained. Stored. During this time, there were no problems such as the wafer W falling over.

  As described above, according to the wafer manufacturing method and the holding jig Z of this embodiment, the relative position between the plurality of wafers W formed by cutting the single crystal C is fixed. And fall can be suppressed.

1 ... Wire saw device (cutting device)
2a ... rotating roller 3 ... wire 4 ... wire row 6 ... slice base 7 ... base 8 ... mounting part 10 ... adhesive 12 ... attachment part 12a ... Clamp part 13 ... End face pressing part 14 ... Holding part 14a ... First pressing part 14b ... Second pressing part 16, 20, 22 ... Elastic body 17a ... Connection part 17b ... -Connection part 19 ... fastening member AX ... central axis (single crystal)
A, B, C, D ... Fixing mechanism C ... Single crystal Sc ... Circumferential surface (single crystal, wafer)
LQ ... stripping solution L ... reference line T ... peeling tank W ... wafer Z ... holding jig

Claims (10)

A method of manufacturing a wafer by cutting a cylindrical single crystal,
Adhering a portion of the circumferential surface of the single crystal to the pedestal with an adhesive;
Cutting the single crystal bonded to the pedestal with a cutting device to form a plurality of wafers bonded to the pedestal and arranged at intervals;
Using a pressing part that presses a part of the circumferential surface of each of the plurality of wafers, the circumferential surface is sandwiched between one or both of the pressing part and the base and between the pressing parts. Fixing the relative position between the plurality of wafers by pressing;
Peeling a plurality of wafers bonded to the pedestal from the pedestal;   2. The method for manufacturing a wafer according to claim 1, comprising the peeling in a state where the pressing portion sandwiches and presses the circumferential surface.   3. The method for manufacturing a wafer according to claim 1, wherein the fixing includes performing a plurality of the wafers bonded to the pedestal and arranged at intervals with the wafer attached to the cutting apparatus.   It is possible to fix a relative position between the plurality of wafers by pressing a part of each circumferential surface of the plurality of wafers arranged at intervals, which is formed by cutting a columnar single crystal fixed to a pedestal. A holding jig having a holding part.   The pressing jig according to claim 4, wherein the pressing portion includes a first pressing portion that sandwiches the circumferential surface between itself and the pedestal and presses a part of the circumferential surface.   The pressing portion includes a pair of second pressing portions that press a part of the circumferential surface while sandwiching the circumferential surface from a direction perpendicular to a central axis direction of the single crystal and a facing direction of the pedestal. The pressing jig according to claim 4 or 5.   Each of the pair of second pressing portions is set on the pedestal side with respect to a reference line in a direction intersecting with the central axis of the single crystal and orthogonal to each other, at a position where the pair of second pressing portions contacts a part of the circumferential surface. The holding jig according to claim 6.   The pressing jig according to any one of claims 4 to 7, wherein a portion of the pressing portion that contacts the circumferential surface is an elastic body.   The holding jig according to any one of claims 4 to 8, further comprising an end surface pressing portion that contacts and supports the end surfaces of the wafers at both ends of the plurality of wafers.   The pressing jig according to any one of claims 4 to 9, further comprising an attachment portion that can be attached to a cutting device that cuts the single crystal.

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