JP2008187158A - Ultrasonic vibration cutting device, ultrasonic dicing tool and peripheral cutting tool attachment flange used for the same cutting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultrasonic vibration cutting device which converts a displacement direction of ultrasonic vibration for cutting operation, wherein ultrasonic vibration is prevented from being transferred in the thickness direction of a peripheral cutting tool to achieve high-precision cutting process. <P>SOLUTION: A flange is attached to a cutting blade 20 which performs rotary drive around an axis line, and which is coupled to an ultrasonic vibrator giving ultrasonic displacement and is fixed to a spindle having an ultrasonic resonator expanding and contracting in the axis direction. The flange consists of a pair of flanges 21, 22, and has a cavity 23 formed between a holding part comprising holding planes 24, 25 on the cutting blade 20 and an attachment hole part 26 provided on the spindle. A part of ultrasonic displacement transferred in the axis direction is absorbed by the cavity 23 to prevent ultrasonic vibration from being transferred in the thickness direction of the cutting blade 20, thereby converting a displacement direction of ultrasonic vibration transferred from the spindle into only a radial direction of the cutting blade 20. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultrasonic vibration cutting apparatus that performs cutting by converting the displacement direction of ultrasonic vibration propagated by an ultrasonic resonator, an ultrasonic dicing tool used therefor, and an outer peripheral tool attaching flange.

  The dicing process is a processing method used when a thin plate-like workpiece is cut into a ridge shape or a groove is formed. Such a dicing process is used, for example, when a silicon wafer is divided into chips in semiconductor manufacturing. In dicing, an outer peripheral cutting tool (cutting blade) that is disk-shaped and has an abrasive layer that forms the blade surface on the outer peripheral portion is used. The cutting blade is rotated at high speed to process the wafer surface. Thus, the silicon wafer is divided into chips.

  By the way, silicon used as a semiconductor material is a hard and brittle material, which is difficult to process, and due to a shortage of processing liquid supply, nozzle mounting position, blade installation accuracy, selection of processing conditions, etc. Undulation and chipping (chips generated at the edge of the machining groove after cutting the workpiece) may be caused and the machining accuracy may be greatly affected.

  Therefore, in order to improve the processing characteristics of such a brittle material that is hard and brittle, a processing method using ultrasonic waves has been devised. For example, Patent Document 1 includes a spindle, a cutting blade attached to the tip of the spindle, and an electrostrictive vibrator provided on the spindle for ultrasonically vibrating the spindle, from the electrostrictive vibrator through the spindle. There is described an ultrasonic vibration cutting device that converts a transmitted ultrasonic vibration and causes a cutting blade to vibrate in a radial direction to cut a workpiece. Further, Patent Document 1 describes an example in which a cutting blade is constituted by a so-called washer blade and is clamped on a spindle by being sandwiched by flanges from both sides thereof.

  In this ultrasonic vibration cutting apparatus, ultrasonic vibration is transmitted in the axial direction of the spindle, and the transmitted direction of the transmitted ultrasonic vibration is changed in the radial direction of the cutting blade at the vibration transmission direction conversion point at the same position as the cutting blade. The cutting blade is ultrasonically vibrated in the radial direction. As a result, the workpiece can be cut by the cutting blade while vibrating the ring-shaped cutting blade so as to repeatedly expand and contract the diameter at high frequency.

JP 2006-147717 A

  However, when the vibration direction is converted as in this ultrasonic vibration cutting device, the ultrasonic vibration transmitted in the axial direction of the spindle is not completely converted into the radial displacement of the cutting blade. Is transmitted as ultrasonic displacement in the blade thickness direction of the cutting blade. And if ultrasonic vibration is transmitted in the blade thickness direction of the cutting blade in this way, the work piece will also be cut in the blade thickness direction of the cutting blade, resulting in a decrease in machining accuracy and a decrease in the life of the cutting blade. It will cause a decline.

  Accordingly, the present invention provides an ultrasonic vibration cutting apparatus that performs cutting by converting the direction of displacement of ultrasonic vibration, and prevents ultrasonic vibration from being transmitted in the blade thickness direction of the outer peripheral blade tool, thereby achieving high-precision cutting. It is an object of the present invention to provide an ultrasonic vibration cutting apparatus capable of performing machining, an ultrasonic dicing tool used therefor, and a flange for attaching an outer peripheral blade tool.

  The outer peripheral blade tool mounting flange of the present invention is an outer peripheral blade tool that is attached to a spindle that includes an ultrasonic resonator that is driven to rotate about an axis and is connected to an ultrasonic transducer that imparts ultrasonic displacement and expands and contracts in the axial direction. The mounting flange is composed of a pair of flanges for holding the outer peripheral blade tool, and a cavity is formed between the holding portion of the outer peripheral blade tool and the mounting hole portion attached to the spindle.

  According to the flange for mounting an outer peripheral blade tool of the present invention, when the displacement direction of the ultrasonic vibration transmitted in the axial direction from the spindle is converted into the radial direction of the outer peripheral blade tool to be sandwiched, it is transmitted in a part of the axial direction. Since the ultrasonic displacement is absorbed by the cavity formed between the clamping part of the outer peripheral blade tool and the mounting hole part attached to the spindle, the ultrasonic vibration is transmitted in the blade thickness direction of the outer peripheral tool. Can be prevented.

  Here, it is desirable that the hollow portion has a cross-sectional shape elongated in the radial direction of the outer peripheral blade tool. As a result, the ultrasonic vibration is absorbed by the cavity portion without disturbing the transmission of the ultrasonic vibration in the radial direction of the outer peripheral blade tool, and the ultrasonic vibration is absorbed by the outer peripheral blade. Transmission in the blade thickness direction of the tool can be prevented.

  Moreover, it is desirable that the hollow portion is formed so as to include on the extended surfaces of the both clamping surfaces of the outer peripheral blade tool. Thereby, it is possible to further prevent the ultrasonic displacement transmitted in a part of the axial direction from being transmitted to the outer peripheral cutting tool along both the clamping surfaces.

  Moreover, it is desirable that the hollow portion is formed in a ring shape or a cylindrical shape centering on the axis of the outer peripheral blade tool. Thereby, when the displacement direction of the ultrasonic vibration transmitted in the axial direction from the spindle is converted into the radial direction of the outer peripheral cutting tool to be sandwiched, a part of the ultrasonic displacement transmitted in the axial direction is converted into the ring shape. Alternatively, it can be further prevented from being absorbed inside the cylindrical cavity and being transmitted to the outer peripheral cutting tool.

  The ultrasonic dicing tool of the present invention is composed of the outer peripheral blade tool mounting flange and the outer peripheral blade tool. By attaching this ultrasonic dicing tool to the spindle, the displacement direction of the ultrasonic vibration transmitted in the axial direction from the spindle is converted only to the radial direction of the outer peripheral blade tool, and the blade surface is converted by this converted ultrasonic displacement. It is possible to perform highly accurate cutting by slightly expanding and contracting only in the radial direction.

  An ultrasonic vibration cutting apparatus according to the present invention includes a spindle including an ultrasonic resonator that is driven to rotate about an axis and is connected to an ultrasonic transducer that applies ultrasonic displacement, and expands and contracts in the axial direction, and is attached to the spindle. The ultrasonic dicing tool is provided. According to this ultrasonic vibration cutting apparatus, it is possible to perform high-precision cutting by slightly expanding and contracting the blade surface of the outer peripheral cutting tool of the ultrasonic dicing tool only in the radial direction.

(1) It consists of a pair of flanges for holding the outer peripheral blade tool, and partly by the outer peripheral blade tool mounting flange in which a cavity is formed between the holding portion of the outer peripheral blade tool and the mounting hole attached to the spindle. The ultrasonic displacement transmitted in the axial direction is absorbed by the cavity formed between the clamping portion of the outer peripheral blade tool and the mounting hole portion attached to the spindle, and the ultrasonic vibration is absorbed in the blade thickness direction of the outer peripheral blade tool. Therefore, the displacement direction of the ultrasonic vibration in the axial direction propagated from the spindle is converted only to the radial direction of the outer peripheral blade tool, and the blade surface is converted by this converted ultrasonic displacement. It is possible to perform highly accurate cutting by slightly expanding and contracting only in the radial direction.

(2) Since the hollow portion has a cross-sectional shape that is elongated in the radial direction of the outer peripheral blade tool, a part of the axis line is prevented without inhibiting transmission of ultrasonic vibration in the radial direction of the outer peripheral blade tool. Since the ultrasonic displacement transmitted in the direction can be absorbed by the cavity and the ultrasonic vibration can be prevented from being transmitted in the blade thickness direction of the outer peripheral blade tool, the axial ultrasonic wave propagated from the spindle can be prevented. The displacement direction of vibration can be efficiently converted into the radial direction of the outer peripheral blade tool, and the blade surface can be slightly expanded and contracted only in the radial direction by the converted ultrasonic displacement to perform highly accurate cutting.

(3) Since the hollow portion is formed so as to include the extended surfaces of the both clamping surfaces of the outer peripheral cutting tool, the ultrasonic displacement transmitted in the axial direction is transmitted along these both clamping surfaces to the outer periphery. Transmission to the blade tool is further prevented, and high-precision cutting can be performed.

(4) Since the hollow portion is formed in a ring shape or a cylindrical shape centering on the axis of the outer peripheral cutting tool, the ultrasonic displacement transmitted in a part of the axial direction can be reduced in this ring shape or circle. Absorption on the inside of the columnar cavity and further transmission to the outer peripheral cutting tool can be further prevented, and high-precision cutting can be performed.

  1A and 1B are diagrams showing an ultrasonic spindle unit as a main part of an ultrasonic vibration cutting apparatus according to an embodiment of the present invention, in which FIG. 1A is a partially cutaway sectional view and FIG. 1B is a right side view. 2A and 2B are diagrams showing the ultrasonic dicing tool of FIG. 1, wherein FIG. 2A is a plan view seen from the ultrasonic spindle unit side, and FIG. 2B is a cross-sectional view. FIG. 3 is a cross-sectional view showing a state where the ultrasonic dicing tool of FIG. 2 is disassembled. 4A is a view as seen from an arrow A in FIG. 3, FIG. 4B is a view as seen from an arrow B in FIG. 3, and FIG. 4C is a view as seen from an arrow C in FIG.

  The ultrasonic vibration cutting apparatus in this embodiment includes an ultrasonic spindle unit 1 shown in FIG. An ultrasonic dicing tool 2 shown in FIG. 2 is attached to the tip of the ultrasonic spindle unit 1. The ultrasonic spindle unit 1 is oscillated by a spindle motor 10 as a drive motor, a spindle shaft 11 rotated around the axis by the spindle motor 10, an ultrasonic transducer 12 that oscillates ultrasonic waves, and an ultrasonic transducer 12. And a horn 13 for transmitting the amplitude of the ultrasonic vibration and supporting the spindle shaft 11.

  As shown in FIGS. 2 to 4, the ultrasonic dicing tool 2 includes a cutting blade 20 as an outer peripheral cutting tool and a pair of flanges 21 and 22 that sandwich the cutting blade 20. The cutting blade 20 is an annular disk (so-called washer blade) in which an abrasive layer serving as a blade surface is formed on the outer peripheral portion, and the center is hollowed out to form a hollow portion 20a. Further, the cutting blade 20 is formed with a bolt hole 20b for inserting a bolt (not shown) for fixing when sandwiched by the flanges 21 and 22.

  The flange 21 is formed so as to project outward from the barrel portion 21b, and a barrel portion 21b in which an insertion hole 21a for inserting a fastener (not shown) such as a bolt for attaching to the spindle shaft 11 is inserted. It is comprised from the collar part 21c. The flange portion 21c is provided with a bolt hole 21d through which a bolt (not shown) for clamping and cutting the cutting blade 20 together with the flange 22 is inserted. The flange 21 has a ring-shaped groove 21e for forming a cavity 23 (see FIG. 2B) between the cutting blade 20 and the flange 22 when the cutting blade 20 is clamped together with the flange 22. Is provided.

  The flange 22 has a barrel portion 22b formed with an insertion hole 22a through which a fastener such as a bolt for attaching to the spindle shaft 11 together with the flange 21 is formed, and a flange portion formed so as to project outward from the barrel portion 22b. 22c. The flange portion 22c is provided with a female screw hole 22d into which a female screw is formed and into which a bolt inserted from the flange 21 side is screwed. In addition, the flange 22 is provided with a recess 22 e that fits with the body portion 21 b of the flange 21 when the cutting blade 20 is clamped together with the flange 21.

  As shown in FIG. 2, the ultrasonic dicing tool 2 constituted by the cutting blade 20 and the flanges 21 and 22 includes a sandwiching portion composed of both sandwiching surfaces 24 and 25 of the flanges 21 and 22 that sandwich the cutting blade 20. A ring-shaped cavity portion 23 is formed between the flanges 21 and 22 and the flange portions 21c and 22c between the mounting holes 26 of the spindle shaft 11 constituted by the insertion holes 21a and 22a. 2 and 3, the lower side is the ultrasonic spindle unit 1 side.

  The ultrasonic vibrator 12 is a piezoelectric vibrator having a natural frequency of 40 kHz. The horn 13 has substantially the same natural frequency as the ultrasonic wave oscillated by the ultrasonic vibrator 12, resonates due to the oscillated ultrasonic vibration, and performs ultrasonic displacement to the spindle shaft 11 while repeating expansion and contraction. It is an ultrasonic resonator that transmits. The ultrasonic dicing tool 2 is fixed to the spindle shaft 11 by a fastener such as a bolt and is rotated about the axis by the spindle shaft 11.

  In the ultrasonic vibration cutting apparatus having the above configuration, first, the cutting blade 20 is sandwiched between the flanges 21 and 22, bolts (not shown) are inserted from the bolt holes 21 d of the flange 21, and the bolt holes 20 b of the cutting blade 20 are formed. Then, it is screwed into the female screw hole 22d of the flange 22 and fixed. Then, the ultrasonic dicing tool 2 is attached to the ultrasonic spindle unit 1 by passing the bolt through the attachment hole 26 of the ultrasonic dicing tool 2 and tightening it with a tightening tool such as a torque wrench.

  In this state, when the ultrasonic transducer 12 is driven to oscillate ultrasonic waves in the axial direction, the horn 13 having a natural frequency resonating with the ultrasonic waves resonates and the ultrasonic displacement is transmitted to the spindle shaft 11. As a result, the ultrasonic displacement is first transmitted to the body portion 21 b of the ultrasonic dicing tool 2 attached to the spindle shaft 11. Since the ultrasonic spindle unit 1 oscillates ultrasonic waves at the resonance frequency of the ultrasonic dicing tool 2, the ultrasonic wave oscillated by the ultrasonic spindle unit 1 is transmitted to the ultrasonic dicing tool 2. The ultrasonic dicing tool 2 is in a resonance state.

  FIG. 5 is an explanatory view showing the propagation of ultrasonic displacement within the ultrasonic dicing tool 2. As shown in FIG. 5, the ultrasonic displacement transmitted to the body portions 21 b and 22 b of the ultrasonic dicing tool 2 starts to propagate radially through the body portions 21 b and 22 b from the attachment hole portion 26. And if it progresses to the end surface of the trunk | drum 21b, an ultrasonic displacement will be reflected and it will progress to the collar parts 21c and 22c, changing the direction of propagation.

  At this time, the ultrasonic displacement in the axial direction of the spindle shaft 11 among the ultrasonic displacements proceeding to the flange portions 21c and 22c is the cavity portion 23 located where the barrel portions 21b and 22b enter the flange portions 21c and 22c. Only the ultrasonic displacement in the radial direction of the cutting blade 20 advances to the flanges 21c and 22c ahead of the cavity 23. The ultrasonic displacement propagated radially in the body portions 21b and 22b in this way is repeatedly reflected on the end surfaces of the body portions 21b and 22b on the side where the spindle shaft 11 is mounted and on the bolt fastening side, and in the radial direction. Only the displacement proceeds to the cutting blade 20.

  As described above, in the ultrasonic vibration cutting device according to the present embodiment, a part of the ultrasonic displacement transmitted in the axial direction is absorbed by the cavity 23, and the ultrasonic vibration is transmitted in the blade thickness direction of the cutting blade 20. Therefore, the displacement direction of the ultrasonic vibration transmitted from the ultrasonic spindle unit 1 is converted only to the radial direction of the cutting blade 20, and the blade surface of the cutting blade 20 is converted by the converted ultrasonic displacement in the radial direction. It is possible to perform high-precision cutting by slightly expanding and contracting only in the radial direction.

  Further, as shown in FIG. 2 (b), the cavity 23 has a cross-sectional shape elongated in the radial direction of the cutting blade 20, so that ultrasonic vibration is radially generated from the body portions 21b and 22b to the flange portions 21c and 22c. Without obstructing the transmission, ultrasonic displacement transmitted in a part of the axial direction is absorbed by the cavity 23 to prevent the ultrasonic vibration from being transmitted in the thickness direction of the cutting blade 20. be able to.

  Further, as shown in FIG. 2B, the cavity 23 is formed so as to include the extended surfaces of both the clamping surfaces 24 and 25 of the cutting blade 20, so that the ultrasonic displacement transmitted in the axial direction. Is further prevented from being transmitted to the cutting blade 20 through the both clamping surfaces 24, 25. Further, since the cavity 23 is formed in a ring shape centering on the axis of the cutting blade 20, ultrasonic displacement transmitted in a part of the axial direction is caused inside the ring-shaped cavity 23. Absorption is further prevented from being transmitted to the outside of the cavity 23.

  In the present embodiment, the outer diameter of the hollow portion 20a of the cutting blade 20 matches the outer diameter of the groove portion 21e, but these do not necessarily have to match. For example, even when the outer diameter of the hollow portion 20a is smaller than the outer diameter of the groove portion 21e, that is, when the peripheral edge portion of the hollow portion 20a of the cutting blade 20 protrudes into the cavity portion 23, it is transmitted in the axial direction. Since the ultrasonic displacement is absorbed by the cavity 23, it is not transmitted to the cutting blade 20 through the cavity 23.

  Next, a modification of the ultrasonic dicing tool 2 in the present embodiment will be described. FIG. 6 is a cross-sectional view showing another embodiment of the ultrasonic dicing tool. FIG. 7 is a cross-sectional view showing a state where the ultrasonic dicing tool of FIG. 6 is disassembled.

  The ultrasonic dicing tool 3 shown in FIGS. 6 and 7 includes a cutting blade 20 and a pair of flanges 31 and 32 that sandwich the cutting blade 20. The difference from the ultrasonic dicing tool 2 described above is that a ring-shaped groove 31a centering on the axis of the cutting blade 20 is provided on the cutting blade 20 side of the flange 31, and the cutting blade 20 of the flange 32 is on the cutting blade 20 side. A substantially ring-shaped projecting portion 32a that fits into the hollow portion 20a and a coaxial ring-shaped groove portion 32b are provided inside the projecting portion 32a.

  The flange 31 includes a barrel portion 31c in which an insertion hole 31b similar to the flange 21 is formed, and a flange portion 31d formed so as to project outward from the barrel portion 31c. The flange 32 includes a body portion 32d in which an insertion hole 32c similar to the flange 22 is formed, and a flange portion 32e formed so as to project outward from the body portion 32d.

  In the ultrasonic dicing tool 3 having this configuration, as shown in FIG. 6, the protruding portion 32 a of the flange 32 is fitted into the hollow portion 20 a of the cutting blade 20 and abuts against the bottom surface of the flange 31 to sandwich the cutting blade 20. To do. A ring-shaped cavity 37 is formed between the inner surface of the groove 31 a of the flange 31 and the inner surface of the groove 32 b of the flange 32. 6 and 7, the lower side is the ultrasonic spindle unit 1 side.

  Also in the ultrasonic dicing tool 3 having this configuration, a part of the ultrasonic displacement transmitted in the axial direction is absorbed by the cavity portion 37 to prevent the ultrasonic vibration from being transmitted in the blade thickness direction of the cutting blade 20. Accordingly, the displacement direction of the ultrasonic vibration transmitted from the ultrasonic spindle unit 1 is converted only to the radial direction of the cutting blade 20, and the blade surface of the cutting blade 20 is made radial by the converted ultrasonic displacement in the radial direction. It is possible to perform high-precision cutting by slightly expanding and contracting only.

  Further, as shown in FIG. 6, the cavity 37 is formed so as to include the extended surfaces of both the clamping surfaces 34 and 35 of the cutting blade 20, so that the ultrasonic displacement transmitted in the axial direction is the both. Transmission to the cutting blade 20 through the clamping surfaces 34 and 35 is further prevented. Further, since the cavity portion 37 is formed in a ring shape centering on the axis of the cutting blade 20, ultrasonic displacement transmitted in a part of the axial direction is caused inside the ring-shaped cavity portion 37. Absorption is further prevented from being transmitted to the outside of the cavity 37.

  The ultrasonic vibration cutting device of the present invention, the ultrasonic dicing tool used in the ultrasonic vibration cutting device, and the outer peripheral blade tool mounting flange are used for cutting by converting the displacement direction of the ultrasonic vibration propagated by the ultrasonic resonator. Useful as a thing.

It is a figure which shows the ultrasonic spindle unit of the principal part of the ultrasonic vibration cutting device in embodiment of this invention, Comprising: (a) is a partially cutaway sectional view, (b) is a right view. It is a figure which shows the tool for ultrasonic dicing of FIG. 1, Comprising: (a) is the top view seen from the ultrasonic spindle unit side, (b) is sectional drawing. It is sectional drawing which shows the state which decomposed | disassembled the ultrasonic dicing tool of FIG. 3A is a view as viewed from an arrow A in FIG. 3, FIG. 3B is a view as viewed from an arrow B in FIG. 3, and FIG. It is explanatory drawing which shows the mode of propagation of the ultrasonic displacement within the tool for ultrasonic dicing. It is sectional drawing which shows another embodiment of an ultrasonic dicing tool. It is sectional drawing which shows the state which decomposed | disassembled the ultrasonic dicing tool of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic spindle unit 2,3 Ultrasonic dicing tool 10 Spindle motor 11 Spindle shaft 12 Ultrasonic vibrator 13 Horn 20 Cutting blade 20a Hollow part 20b, 21d Bolt hole 21, 22, 31, 32 Flange 21a, 22a, 31b 32c Insertion hole 21b, 22b, 31c, 32d Body part 21c, 22c, 31d, 32e Gutter part 21e Groove part 22d Female screw hole 22e Recess 23, 37 Cavity part 24, 25, 34, 35 Clamping face 26 Mounting hole part 31a, 32b Concave part 32a Convex part

Claims (6)

An outer peripheral blade tool mounting flange that is attached to a spindle that includes an ultrasonic resonator that is driven to rotate around an axis and is connected to an ultrasonic transducer that imparts ultrasonic displacement and expands and contracts in the axial direction,
It consists of a pair of flanges that hold the outer peripheral tool,
A flange for attaching an outer peripheral blade tool in which a cavity is formed between a holding portion of the outer peripheral blade tool and an attachment hole attached to the spindle.   The flange for attaching an outer peripheral blade tool according to claim 1, wherein the hollow portion has a cross-sectional shape elongated in a radial direction of the outer peripheral blade tool.   The flange for outer peripheral blade tool attachment according to claim 1 or 2, wherein the hollow portion is formed so as to include an extended surface of both clamping surfaces of the outer peripheral blade tool.   The flange for attaching an outer peripheral blade tool according to any one of claims 1 to 3, wherein the hollow portion is formed in a ring shape or a cylindrical shape centering on an axis of the outer peripheral blade tool. A flange for attaching an outer peripheral blade tool according to any one of claims 1 to 4,
A tool for ultrasonic dicing composed of a peripheral edge tool. A spindle comprising an ultrasonic resonator that is driven to rotate about an axis and is connected to an ultrasonic transducer that imparts ultrasonic displacement and expands and contracts in the axial direction;
An ultrasonic vibration cutting apparatus comprising: the ultrasonic dicing tool according to claim 5 attached to the spindle.

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