JP7592366B2 - Clamping tool and grinding method - Google Patents

Description

The present invention relates to a clamping jig that is attached to a disk-shaped mounting table on which a workpiece is placed so as to surround the mounting table, and a method for grinding a workpiece held on the mounting table using this clamping jig.

Low temperature co-fired ceramics (LTCC) substrates are used as substrates for manufacturing devices such as high-frequency modules. Workpieces such as LTCC substrates are sometimes ground in a grinding device.

Grinding devices generally include a chuck table with a holding surface that holds one side of the workpiece, and a grinding wheel with multiple grinding stones arranged in a circular ring shape (see, for example, Patent Document 1). In this grinding device, the other side of the workpiece is ground by contacting the multiple grinding stones with the other side of the workpiece, which is the back side of the one side, while rotating the chuck table and the grinding wheel.

JP 2020-25989 A

Generally, the chuck table can suck one side of the workpiece by generating negative pressure in the space near its holding surface. The sucked one side of the workpiece then comes into close contact with the holding surface of the chuck table, thereby holding the workpiece on the chuck table. However, if the workpiece is thick and/or the surface roughness of one side of the workpiece is large, even if negative pressure is generated in the space near the holding surface of the chuck table, the holding surface of the workpiece and one side of the workpiece may not come into sufficient contact with each other.

In this case, gas constantly flows into the gap between the workpiece holding surface and one side of the workpiece, making it impossible to maintain the desired negative pressure in the space near the chuck table's holding surface. As a result, it may become impossible or difficult to hold the workpiece by the chuck table.

On the other hand, by adhering the center of a tape whose outer periphery is attached to a ring frame to one side of a workpiece, such a workpiece can be held on the chuck table. In other words, the sucked tape comes into close contact with the holding surface of the chuck table, and the workpiece can be held on the chuck table via this tape. In this case, however, it is necessary to prepare tape and adhere the tape to one side of the workpiece, which increases the manufacturing cost of the device manufactured using the workpiece.

In view of this, the object of the present invention is to provide a clamping jig capable of holding a workpiece on a mounting table without the workpiece being sucked by the mounting table on which the workpiece is placed, and a method for grinding a workpiece held on a mounting table using this clamping jig.

According to one aspect of the present invention, there is provided a clamping jig that is attached to a disk-shaped mounting table on which a workpiece is placed so as to surround the mounting table, the clamping jig comprising an annular frame body, a fixing portion that fixes the frame body to the mounting table, and a plurality of clamping portions disposed on the frame body, each of the plurality of clamping portions having a movable member that is movable along the radial direction of the frame body, and a movement limiting member that limits the movement of the movable member along the radial direction of the frame body.

In the clamping jig of the present invention, it is preferable that the movable member includes a ferromagnetic material and the movement limiting member includes a magnet.

According to another aspect of the present invention, there is provided a grinding method including: an attachment step of attaching the clamping jig to the mounting table using the fixing portion of the clamping jig; a mounting step of mounting the workpiece on the mounting table; a workpiece holding step of, after the attachment step and the mounting step, moving the movable members included in each of the plurality of clamping portions radially inward of the frame body and, with the tip surface of the movable member in contact with the side surface of the workpiece, restricting the movement of the movable members radially outward of the frame body with the movement limiting member, thereby holding the workpiece on the mounting table; and, after the workpiece holding step, a grinding step of grinding the workpiece.

In the present invention, the outward movement of the movable member that is in contact with the workpiece by moving it inward along the radial direction of the frame body can be restricted by the movement restricting member. This makes it possible to restrict the movement of the workpiece placed on the placement table by the movable member that is in contact with the workpiece.

In other words, in the present invention, the workpiece can be held on the mounting table without being sucked into the mounting table. As a result, even if the workpiece is thick and/or one side of the workpiece has a large surface roughness, there is no need to attach tape to one side of the workpiece, so that an increase in the manufacturing cost of a device manufactured using this workpiece can be suppressed.

FIG. 1A is a top view that shows a schematic diagram of an example of a clamping jig, and FIG. 1B is a front view that shows a schematic diagram of an example of a clamping jig. FIG. 2 is a perspective view illustrating an example of a grinding apparatus. FIG. 3 is a flow chart that illustrates an example of a grinding method. FIG. 4A is a top view that shows a schematic view of the mounting step, and FIG. 4B is a front view that shows a schematic view of the mounting step. FIG. 5A is a top view that shows a schematic view of the placement step, and FIG. 5B is a front view that shows a schematic view of the placement step. FIG. 6A is a top view that shows a schematic view of the workpiece holding step, and FIG. 6B is a front view that shows a schematic view of the workpiece holding step. FIG. 7A is a top view that shows a schematic diagram of another example of the clamping jig, and FIG. 7B is a front view that shows a schematic diagram of another example of the clamping jig.

An embodiment of the present invention will be described with reference to the attached drawings. Fig. 1(A) is a top view showing an example of a clamping jig of the present invention, and Fig. 1(B) is a front view showing an example of a clamping jig of the present invention. The clamping jig 2 shown in Figs. 1(A) and 1(B) has an annular frame body 4.

The frame body 4 is fixed to the disk-shaped mounting table in a state where it surrounds the mounting table described below. In other words, the inner diameter of the frame body 4 is longer than the diameter of the mounting table, and the frame body 4 is fixed to the mounting table in a state where the inner surface of the frame body 4 faces the side surface of the mounting table. There are no restrictions on the material of the frame body 4. For example, the frame body 4 is made of a metal material or ceramics, etc.

Furthermore, the frame body 4 has four screw holes that penetrate from its outer surface to its inner surface. These screw holes are provided at approximately equal intervals along the circumferential direction of the frame body 4. A bolt (fixing part) 6 extending along the radial direction (first direction) of the frame body 4 is inserted into each screw hole. There is no restriction on the material of the bolt 6. For example, the bolt 6 is made of a metal material or ceramics.

The bolt 6 has a cylindrical head 6a with a hexagonal groove formed on the top surface, and a cylindrical shaft 6b that is fixed to the opposite side of the top surface of the head 6a and has a screw thread on its outer periphery that corresponds to the screw thread on the screw hole of the frame 4. At least a part of the shaft 6b is inserted into each screw hole.

The head 6a and the shaft 6b are arranged so that the rotation axis when the bolt 6 is screwed into the screw hole passes through the center of the head 6a and the shaft 6b. The length of the shaft 6b along the rotation axis is longer than the length of the head 6a along the rotation axis. The width (diameter) of the shaft 6b along the direction perpendicular to the rotation axis is shorter than the width (diameter) of the head 6a along the direction perpendicular to the rotation axis.

Each of the four bolts 6 is used when mounting the clamp jig 2 on the mounting table, which will be described later. Specifically, by rotating each bolt 6 in the direction in which the bolt 6 is tightened while the inner surface of the frame body 4, with the shaft portion 6b inserted into each screw hole, faces the side surface of the mounting table, the tip surface of the shaft portion 6b of each bolt 6 (the surface opposite the surface fixed to the head portion 6a) is brought into contact with the side surface of the mounting table. This fixes the frame body 4 so that it surrounds the mounting table. In other words, the clamp jig 2 is mounted on the mounting table.

Clamps 8 are provided on the upper surface of the frame body 4 above each of the four screw holes provided in the frame body 4. That is, four clamps 8 are provided on the upper surface of the frame body 4, and each clamp 8 is provided at approximately equal intervals along the circumferential direction of the frame body 4. The clamps 8 are fixed to the frame body 4 and have a rectangular parallelepiped base 10 that protrudes radially inward from the inner surface of the frame body 4. There are no limitations on the material of the base 10. For example, the base 10 is made of a metal material or ceramics.

The base 10 has a groove 10a that penetrates from its outer surface to its inner surface and opens at its top surface. In a cross section perpendicular to the first direction, this groove 10a includes a portion whose width along the tangential direction (second direction) of the frame 4 decreases the closer it gets to the top surface. That is, the groove 10a has the widest width along the second direction at its bottom surface, and the width of the opening provided on the top surface of the base 10 along the second direction is the narrowest.

A flat magnet (movement limiting member) 10b is built into the lower part of the base 10, which is located between the bottom surface of the groove 10a and the upper surface of the frame body 4. This magnet 10b includes a permanent magnet. A part of the movable member 12 is inserted into the bottom surface of the groove 10a. This movable member 12 has a foot 12a with a lower surface that contacts the bottom surface of the groove 10a. The foot 12a includes a ferromagnetic material.

The length of the foot 12a in the first direction is shorter than the length of the base 10 in the first direction. In addition, in a plane perpendicular to the first direction, the foot 12a has a lower portion whose width decreases the farther away from the lower surface, and an upper portion whose width is generally constant. The width of the upper portion of the foot 12a in the second direction is shorter than the width of the opening provided in the upper surface of the base 10 in the second direction.

The thickness of the entire foot 12a in a direction perpendicular to the first and second directions (third direction) is greater than the depth of the groove 10a in the third direction. The thickness of the lower part of the foot 12a in the third direction is less than the depth of the groove 10a in the third direction. Therefore, the upper part of the foot 12a protrudes upward from the base 10.

Furthermore, a rectangular parallelepiped-shaped gripped part 12b is fixed to the upper end of the foot part 12a. Specifically, the gripped part 12b extends along the first direction, and its outer end is fixed to the upper end of the foot part 12a. There is no restriction on the material of the gripped part 12b. For example, the gripped part 12b is made of a metal material or ceramics.

The length of the gripped portion 12b in the first direction is longer than the length of the base 10 in the first direction. The width of the gripped portion 12b in the second direction is wider than the width of the opening provided on the upper surface of the base 10 in the second direction. This gripped portion 12b is gripped when the operator moves the movable member 12 in the first direction.

For example, the operator can grasp the gripped portion 12b and move the movable member 12 radially inward of the frame body 4 so that the lower surface of the foot 12a contacts the inner end of the bottom surface of the groove 10a. The operator can also grasp the gripped portion 12b and move the movable member 12 radially outward of the frame body 4 so as to separate the movable member 12 from the base 10 (remove the movable member 12 from the groove 10a).

A flat contact portion 12c is fixed to the inner end of the grasped portion 12b. There are no limitations on the material of the contact portion 12c. For example, the contact portion 12c is made of a soft elastic material such as resin. The width of the contact portion 12c in the second direction is longer than the width of the grasped portion 12b in the second direction. In addition, the thickness of the contact portion 12c in the third direction is, for example, approximately equal to the thickness of the grasped portion 12b in the third direction.

The inner surface of the contact portion 12c (the tip surface of the movable member 12) faces the side surface of the workpiece placed on the mounting table when the clamping jig 2 is attached to the mounting table described below. In this state, the operator can grasp the gripped portion 12b and move the movable member 12 radially inward of the frame 4 to bring the tip surface of the movable member 12 into contact with the side surface of the workpiece placed on the mounting table.

Figure 2 is a perspective view showing a schematic example of a grinding device including a mounting table on which the clamp jig 2 is attached. Note that the X-axis direction (front-back direction) and the Y-axis direction (left-right direction) shown in Figure 2 are directions perpendicular to each other on a horizontal plane, and the Z-axis direction (up-down direction) is a direction (vertical direction) perpendicular to the X-axis direction and the Y-axis direction.

The grinding device 14 shown in FIG. 2 has a base 16 that supports each component. An opening 16a having a longitudinal portion extending along the X-axis direction is formed on the upper surface of the base 16. A ball screw type X-axis direction movement mechanism (not shown) is disposed inside the opening 16a. The X-axis direction movement mechanism has a pair of guide rails (not shown) that extend along the X-axis direction.

An X-axis moving plate (not shown) is connected to the top of the pair of guide rails in a manner that allows it to slide along the pair of guide rails. A screw shaft (not shown) extending along the X-axis direction is disposed between the pair of guide rails. A motor (not shown) for rotating the screw shaft is connected to one end of the screw shaft.

A nut section (not shown) that houses balls that roll on the surface of the rotating screw shaft is provided on the surface of the screw shaft where the spiral grooves are formed, forming a ball screw. That is, when the screw shaft rotates, the balls circulate inside the nut section, causing the nut section to move along the X-axis direction. This nut section is also fixed to the underside of the X-axis moving plate (not shown). Therefore, when the screw shaft is rotated by a motor, the X-axis moving plate moves along the X-axis direction together with the nut section.

A table cover 18 is provided on the X-axis moving table. In addition, accordion-shaped dust-proof and water-resistant covers 20 that cover the upper side of the X-axis moving mechanism and follow the X-axis direction are provided in front and behind the table cover 18. When the X-axis moving table is moved along the X-axis direction by the X-axis moving mechanism, the table cover 18 moves together with the X-axis moving table, and the dust-proof and water-resistant cover 20 expands and contracts in accordance with the moving table cover 18.

A mounting table 22 is provided on the table cover 18. The mounting table 22 has a frame 24 made of, for example, a metal material such as stainless steel or ceramics. The frame 24 has a disk-shaped bottom wall and an annular side wall extending upward from the outer periphery of the bottom wall. A recess is defined on the upper surface side of the frame 24 by the bottom wall and the side wall.

A disk-shaped porous plate 26 made of ceramics is fixed in this recess. The upper surface of the porous plate 26 (the holding surface of the mounting table 22) is configured in a shape corresponding to the side of a cone. The lower surface side of the porous plate 26 is connected to a suction source (not shown) such as an ejector via, for example, a flow path (not shown) and a valve (not shown) provided inside the frame 24.

When the valve is opened while this suction source is operating, negative pressure is generated on the upper surface of the porous plate 26. In addition, the mounting table 22 is connected to a rotary drive source (not shown) such as a motor. When this rotary drive source operates, the mounting table 22 rotates around a rotation axis that passes through the center of its holding surface and runs along the Z-axis direction or a direction slightly tilted from the Z-axis direction.

In addition, an operation panel 28 for inputting grinding conditions and the like is provided near the front end of the opening 16a. In addition, a rectangular parallelepiped support structure 30 extending upward is provided near the rear end of the opening 16a. A Z-axis direction movement mechanism 32 is provided on the front side of the support structure 30 (i.e., the operation panel 28 side). The Z-axis direction movement mechanism 32 has a pair of Z-axis guide rails 34 extending along the Z-axis direction.

A Z-axis moving plate 36 is connected to the front side of the pair of Z-axis guide rails 34 in a manner that allows it to slide along the pair of Z-axis guide rails 34. A screw shaft 38 extending along the Z-axis direction is disposed between the pair of Z-axis guide rails 34. A motor 40 for rotating the screw shaft 38 is connected to one end of the screw shaft 38.

A nut portion (not shown) that accommodates balls that roll on the surface of the rotating screw shaft 38 is provided on the surface of the screw shaft 38 where the helical grooves are formed, forming a ball screw. That is, when the screw shaft 38 rotates, the balls circulate inside the nut portion, causing the nut portion to move along the Z-axis direction. In addition, this nut portion is fixed to the back side of the Z-axis moving plate 36. Therefore, when the screw shaft 38 is rotated by the motor 40, the Z-axis moving plate 36 moves along the Z-axis direction together with the nut portion.

A support 42 is provided on the front side of the Z-axis moving plate 36. The support 42 supports a grinding unit 44. The grinding unit 44 has a cylindrical spindle housing 46 fixed to the support 42. A columnar spindle 48 extending along the Z-axis direction is partially housed in the spindle housing 46 in a rotatable state.

A motor 50 for rotating the spindle 48 is connected to the upper end of the spindle 48. The lower end of the spindle 48 is exposed from the spindle housing 46, and the upper part of a disk-shaped wheel mount 52 made of a metal material such as stainless steel is fixed to this lower end.

An annular grinding wheel 54 with a diameter roughly equal to that of the wheel mount 52 is attached to the bottom of the wheel mount 52. The grinding wheel 54 has an annular wheel base 56 made of a metal material such as stainless steel. A number of grinding stones 58 are fixed to the underside of the wheel base 56.

Each of the grinding wheels 58 is rectangular and arranged in a dispersed manner along the circumferential direction of the wheel base 56. Furthermore, a nozzle (not shown) is provided near or inside the grinding wheel 54 to supply grinding fluid such as water to the grinding surface when grinding the workpiece. When the motor 50 operates, the spindle 48, wheel mount 52, and grinding wheel 54 rotate around a straight line along the Z-axis direction or a direction slightly tilted from the Z-axis direction as the rotation axis.

Figure 3 is a flow chart showing an example of a method for grinding a workpiece in the grinding device 14. In the grinding method shown in Figure 3, the clamp jig 2 is first attached to the mounting table 22 (attaching step: S1). Figure 4 (A) is a top view showing the attachment step (S1) and Figure 4 (B) is a front view showing the attachment step (S1).

In the mounting step (S1), first, the clamp jig 2 is positioned so that the frame body 4 surrounds the mounting table 22. For example, the clamp jig 2 is positioned so that the upper surface of the frame body 24 of the mounting table 22 and the upper surface of the frame body 4 of the clamp jig 2 are positioned on the same plane.

Next, each of the four bolts 6 is rotated in the direction in which the bolt 6 is tightened, so that the tip surface of the shaft portion 6b of each bolt 6 comes into contact with the outer surface of the frame 24 (the side surface of the mounting table 22) (see Figures 4(A) and 4(B)). This causes the clamp jig 2 to be attached to the mounting table 22.

Once the mounting step (S1) is completed, the workpiece is placed on the placement table 22 (placement step: S2). FIG. 5(A) is a top view that shows the placement step (S2) in a schematic manner, and FIG. 5(B) is a front view that shows the placement step (S2) in a schematic manner. In the placement step (S2), the workpiece 11 is placed on the placement table 22 so that the center of one side of the workpiece 11 is aligned with the center of the holding surface of the placement table 22 (the upper surface of the porous plate 26).

The workpiece 11 is, for example, an LTCC substrate having a regular hexagonal prism shape. The workpiece 11 is thicker than the clamping portion 8 of the clamping jig 2. For example, if the thickness of the clamping portion 8 is about 2 mm, the thickness of the workpiece 11 is about 3 mm to 10 mm. The workpiece 11 is placed on the mounting table 22 so that four of the sixteen side surfaces face the tip surface (the inner surface of the contact portion 12c) of the movable member 12 of the clamping portion 8 (see Figures 5(A) and 5(B)).

When the placement step (S2) is completed, the workpiece 11 is held on the placement table 22 using the clamp jig 2 (workpiece holding step: S3). Figure 6(A) is a top view that shows the workpiece holding step (S3) in a schematic manner, and Figure 6(B) is a front view that shows the workpiece holding step (S3) in a schematic manner.

In the workpiece holding step (S3), the tip surface of the movable member 12 of the clamp unit 8 is brought into contact with the side surface of the workpiece 11. Specifically, the operator holds the gripped portion 12b of the movable member 12 and moves the movable member 12 radially inward of the frame 4 until the tip surface of the movable member 12 comes into contact with the side surface of the workpiece 11 (see Figures 6(A) and 6(B)).

At this time, the foot 12a of the movable member 12, which includes a ferromagnetic material, is attracted to the magnet 10b, which includes a permanent magnet, so the operator moves the movable member 12 with a force exceeding a predetermined magnitude. In addition, the movable member 12, whose tip surface is in contact with the side surface of the workpiece 11, is also attracted to the magnet 10b in the same manner.

In other words, even if a force of a predetermined magnitude or less is applied to the movable member 12 whose tip surface is in contact with the side surface of the workpiece 11, the movable member 12 will not move. This makes it possible to restrict the movement of the movable member 12 radially outward from the frame body 4. As a result, the movement of the workpiece 11 on the mounting table 22 is restricted, and the workpiece 11 can be held on the mounting table 22.

Once the workpiece holding step (S3) is completed, the workpiece 11 is ground (grinding step: S4). In the grinding step (S4), first, the X-axis direction movement mechanism moves the mounting table 22 so that the grinding wheel 54 is positioned above the workpiece 11. Next, the rotary drive source rotates the mounting table 22, and the motor 50 rotates the grinding wheel 54.

Next, while rotating the mounting table 22 and the grinding wheel 54, the Z-axis movement mechanism 32 lowers the grinding wheel 54 so that the lower surfaces of the multiple grinding wheels 58 come into contact with the upper surface of the workpiece 11. This allows the upper surface side of the workpiece 11 to be ground by the multiple grinding wheels 58.

In the grinding method described above, the foot 12a of the movable member 12 having the contact portion 12c that comes into contact with the workpiece 11 by moving the movable member 12 inward along the radial direction of the frame body 4 is attracted by the magnet 10b. This makes it possible to suppress the movement of the workpiece 11 placed on the mounting table 22 by the movable member 12 whose contact portion 12c comes into contact with the workpiece 11.

In other words, in the above-described grinding method, the workpiece 11 can be held on the mounting table 22 without being sucked into the mounting table 22. As a result, even if the workpiece 11 is thick and/or one side of the workpiece 11 has a large surface roughness, there is no need to attach tape to one side of the workpiece 11, so that an increase in the manufacturing cost of a device manufactured using the workpiece 11 can be suppressed.

In addition, the clamp jig 2 is attached to the mounting table 22 using the bolts 6, so it can be easily attached and detached from the mounting table 22. In addition, in the clamp jig 2, the movable member 12 can be separated from the base 10. Therefore, the workpiece 11 can be ground on the mounting table 22 without using the clamp jig 2, while the frame 4 remains fixed to the mounting table 22.

In other words, while the frame 4 is fixed to the mounting table 22, the mounting table 22 can use a suction source connected to the underside of the porous plate 26 to perform grinding of the workpiece 11 (e.g., thin finish grinding) while holding the workpiece 11 by suction. This reduces the effort required when using the clamping jig 2 to switch between grinding the workpiece 11 while holding it by suction and grinding the workpiece 11 while holding it on the mounting table 22 using the clamping jig 2.

In addition, in the clamp jig 2, the movable member 12 can be moved within a predetermined range along the first direction, so that workpieces 11 of various sizes can be held on the mounting table 22.

The above-mentioned clamping jig 2 and grinding method are one aspect of the present invention, and the present invention is not limited to the above-mentioned clamping jig or grinding method. For example, the clamping portion of the clamping jig 2 may have any structure as long as it is movable along the radial direction of the frame body 4 and is capable of restricting the movement of the workpiece 11 radially outward of the frame body 4.

Figure 7 (A) is a top view showing a schematic example of a clamp jig having a clamp part having a structure different from the clamp part 8 shown in Figures 1 (A) and 1 (B), and Figure 7 (B) is a front view showing a schematic example of this clamp jig.

In the following, explanations of components common to the clamp jig 2 shown in Figures 1(A) and 1(B) will be omitted. Also, the first direction, second direction, and third direction described below refer to the radial direction of the frame body 4, the tangential direction of the frame body 4, and the directions perpendicular to the first direction and second direction, respectively, as described above.

The clamp jig 60 shown in Figures 7(A) and 7(B) has four clamp parts 62. Each clamp part 62 is provided on the upper surface of the frame body 4 above each of the four screw holes provided in the frame body 4. In other words, four clamp parts 62 are provided on the upper surface of the frame body 4, and each clamp part 62 is provided at approximately equal intervals along the circumferential direction of the frame body 4.

The clamp portion 62 has a rectangular parallelepiped base portion 64 that is fixed to the frame body 4 and protrudes radially inward from the inner surface of the frame body 4. There are no limitations on the material of the base portion 64. For example, the base portion 64 is made of a metal material, ceramics, or the like.

The base 64 has a cylindrical screw hole that opens on its upper surface, and a bolt (movement limiting member) 66 is inserted into this screw hole. There is no restriction on the material of the bolt 66. For example, the bolt 66 is made of a metal material or ceramics.

The bolt 66 has a cylindrical head 66a with a hexagonal groove formed on the top surface, and a cylindrical shaft 66b that is fixed to the opposite side of the top surface of the head 66a and has a thread on its outer periphery that corresponds to the thread on the screw hole in the base 64. At least a part of the shaft 66b is inserted into the screw hole in the base 64.

The head 66a and the shaft 66b are arranged so that the rotation axis when the bolt 66 is screwed into the screw hole passes through the center of the head 66a and the shaft 66b. The length of the shaft 66b along the rotation axis is longer than the length of the head 66a along the rotation axis. The width (diameter) of the shaft 66b along the direction perpendicular to the rotation axis is shorter than the width (diameter) of the head 66a along the direction perpendicular to the rotation axis.

A movable member 68 is provided between the head 66a and base 64 of the bolt 66. Specifically, the movable member 68 has a rectangular parallelepiped gripped portion 68a that extends along the first direction. This gripped portion 68a has a through hole 68b that penetrates from its top surface to its bottom surface and extends along the first direction. The shaft portion 66b of the bolt 66 is passed through this through hole 68b.

There are no limitations on the material of the gripped portion 68a. For example, the gripped portion 68a is made of a metal material or ceramics. The width of the through hole 68b in the gripped portion 68a in the second direction is shorter than the width (diameter) of the head 66a of the bolt 66 in the second direction, and longer than the width (diameter) of the shaft 66b in the second direction.

Therefore, when the shaft 66b is screwed into the threaded hole of the base 64 through the through hole 68b and the head 66a is not in contact with the gripped portion 68a, the movable member 68 can move within a predetermined range along the first direction, but will not separate from the base 64. On the other hand, if the bolt 66 is rotated in the direction in which the bolt 66 is tightened until the head 66a comes into contact with the gripped portion 68a, the movable member 68 is fixed to the base 64.

For example, the operator can grasp the graspable portion 68a of the movable member 68 that is movable along the first direction, move the movable member 12 to a desired position, and then tighten the bolt 66 to fix the movable member 68 to the base 64. That is, the operator can fix the movable member 68 to a desired position within a predetermined range along the first direction.

A flat contact portion 68c is fixed to the inner end of the gripped portion 68a. There are no limitations on the material of the contact portion 68c. For example, the contact portion 68c is made of a soft elastic material such as resin. The width of the contact portion 68c in the second direction is longer than the width of the gripped portion 68a in the second direction. In addition, the thickness of the contact portion 68c in the third direction is, for example, approximately equal to the thickness of the gripped portion 68a in the third direction.

When the clamp jig 60 is attached to the mounting table 22 of the grinding device 14 shown in FIG. 2, the inner surface of the contact portion 68c (the tip surface of the movable member 68) faces the side surface of the workpiece placed on the mounting table 22. In this state, the operator can grasp the gripped portion 68a and move the movable member 68 radially inward of the frame body 4, thereby bringing the tip surface of the movable member 68 into contact with the side surface of the workpiece placed on the mounting table 22.

Therefore, by using the clamp jig 60, similar to the clamp jig 2 shown in Figures 1(A) and 1(B), the workpiece 11 can be held on the mounting table 22 on which the workpiece 11 is placed, without the workpiece 11 being sucked by the mounting table 22.

Furthermore, compared to clamp jig 2, clamp jig 60 is preferable in that it allows easy movement of movable member 68 before fixing movable member 68 with movement limiting member (bolt 66). On the other hand, clamp jig 2 is preferable compared to clamp jig 60 in that it does not require the effort of fixing movable member 12 with movement limiting member (magnet 10b).

In addition, the clamping jigs 2, 60 described above are provided with four clamping sections 8, 62, but the number of clamping sections of the clamping jigs of the present invention is not limited to four and may be any number as long as it is plural.

In addition, in the clamping jigs 2 and 60 described above, the movable members 12 and 68 are provided with flat tip surfaces (the inner surfaces of the contact portions 12c and 68c), but the shape of the tip surface of the movable member of the clamping jig of the present invention does not have to be flat. For example, when a disk-shaped workpiece is held on the mounting table 22, this tip surface may be a curved surface having a curvature corresponding to the curvature of the workpiece.

In addition, in the clamping jig 2 described above, the magnet 10b includes a permanent magnet, but the magnet of the clamping jig of the present invention may include an electromagnet. When the magnet does not include a permanent magnet but includes an electromagnet, this is preferable in that the movable member 12 can be easily moved to a desired position by adjusting the current supplied to the electromagnet, and the movement of the frame body 4 radially outward from that position can be easily restricted. On the other hand, when the magnet does not include an electromagnet but includes a permanent magnet, this is preferable in that the manufacturing costs of the clamping jig can be reduced.

In addition, while the clamping jigs 2, 60 described above are provided with movable members 12, 68 that are moved manually, the clamping jigs of the present invention may include an actuator such as an air cylinder that moves the movable members 12, 68. If the clamping jig includes such an actuator, this is preferable in that it can prevent contamination of the workpiece placed on the mounting table caused by an operator working near the workpiece. On the other hand, if the clamping jig does not include such an actuator, this is preferable in that it can reduce the manufacturing costs of the clamping jig.

In addition, in the grinding method described above, the workpiece 11, which is an LTCC substrate, is held on the mounting table 22 using the clamping jigs 2 and 60, but in the grinding method of the present invention, the workpiece is not limited to an LTCC substrate. For example, the workpiece may be a wafer made of a semiconductor material such as Si (silicon), SiC (silicon carbide), or GaN (gallium nitride).

In addition, in the grinding method described above, the mounting step (S2) is performed after the mounting step (S1), but in the grinding method of the present invention, the mounting step (S1) may be performed after the mounting step (S2). In addition, the structures and methods according to the above-described embodiments may be modified as appropriate without departing from the scope of the present invention.

2: Clamp jig 4: Frame 6: Bolt (6a: head, 6b: shaft)
8: Clamp portion 10: Base portion (10a: groove, 10b: magnet)
12: Movable member (12a: foot part, 12b: gripped part, 12c: contact part)
14: Grinding device 16: Base (16a: opening)
[0033] 18: Table cover 20: Dust-proof/water-proof cover 22: Placement table 24: Frame 26: Porous plate 28: Operation panel 30: Support structure 32: Z-axis direction movement mechanism 34: Z-axis guide rail 36: Z-axis movement plate 38: Screw shaft 40: Motor 42: Support 44: Grinding unit 46: Spindle housing 48: Spindle 50: Motor 52: Wheel mount 54: Grinding wheel 56: Wheel base 58: Grinding stone 60: Clamping jig 62: Clamping portion 64: Base 66: Bolt (66a: head, 66b: shaft)
68: Movable member (68a: gripped part, 68b: through hole, 68c: contact part)

Claims (3)

A clamping jig that is attached to a disk-shaped mounting table on which a workpiece is placed so as to surround the mounting table,
A circular frame body;
a fixing portion that fixes the frame to the mounting table;
a plurality of clamp portions disposed on the frame body;
Each of the plurality of clamp portions is
A movable member that is movable along a radial direction of the frame body;
a movement limiting member that limits movement of the movable member along a radial direction of the frame body. The movable member includes a ferromagnetic material,
2. The clamping jig of claim 1, wherein the movement limiting member includes a magnet. a mounting step of mounting the clamping jig on the mounting table by using the fixing portion of the clamping jig according to claim 1 or 2;
a placing step of placing the workpiece on the placing table;
a workpiece holding step of, after the mounting step and the placing step, moving the movable members included in each of the plurality of clamping portions radially inward of the frame body, and restricting the movement of the movable members radially outward of the frame body with the movement limiting members while bringing the tip surfaces of the movable members into contact with the side surfaces of the workpiece, thereby holding the workpiece on the placing table;
a grinding step of grinding the workpiece after the workpiece holding step;
A grinding method comprising:

Images