JP2004276182A - Water jet machining apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water jet machining apparatus, making the abrasive grain concentration of machining water jetted from a nozzle uniform to stabilize the machining accuracy. <P>SOLUTION: This water jet machining apparatus includes: a workpiece holding mechanism; a nozzle 522 for injecting a water jet to the workpiece held by the workpiece holding mechanism; and a machining water supply means 6 for supplying machining water mixed with abrasive grains to the nozzle. The machining water supply means includes a high pressure water generating means 62 and a machining water delivery means 64. The machining water delivery means includes a cylinder and a partition member partitioning the inside of the cylinder into a first chamber and a second chamber and displaced depending on the pressures of both chambers. The first chamber is communicated with the high pressure water generating means and communicated with a water draining means for suitably discharging the high pressure water in the first chamber. The second chamber is communicated with a machining water storing means 63 storing the machining water, communicated with the nozzle, and provided with a machining water stirring means 8 for stirring the machining water in the second chamber. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a water jet processing apparatus for cutting a workpiece such as a semiconductor wafer by jetting a high-pressure water jet.
[0002]
[Prior art]
In a semiconductor device manufacturing process, circuits such as ICs and LSIs are formed in a large number of regions arranged in a lattice on the surface of a semiconductor wafer having a substantially disk shape, and each region where the circuits are formed is formed into a predetermined street. Individual semiconductor chips are manufactured by dicing along a cutting line called "cutting line". The semiconductor chips thus divided are packaged and widely used for electric devices such as mobile phones and personal computers.
Electric devices such as mobile phones and personal computers are required to be lighter and smaller, and a package technology that can reduce the size of a semiconductor chip package called a chip size package (CSP) has been developed. As one of the CSP technologies, a package technology called Quad Flat Non-lead Package (QFN) has been put to practical use. This package technology called QFN is based on a technique in which a plurality of connection terminals corresponding to connection terminals of a semiconductor chip are formed, and a plurality of semiconductor chips are mounted on a metal plate such as a copper plate in which streets defined for each semiconductor chip are formed in a grid pattern. Are arranged in a matrix, and the metal plate and the semiconductor chip are integrated by a resin portion molded with resin from the back surface side of the semiconductor chip to form a CSP substrate. The CSP substrate is cut along the streets to be divided into individually packaged chip size packages (CSP).
[0003]
The CSP substrate is cut by a precision cutting device generally called a dicing device. The dicing apparatus includes a cutting blade provided with an annular abrasive layer, and cuts the CSP substrate along the street by rotating the cutting blade and relatively moving along the street of the CSP substrate. Divide into CSPs. However, when the CSP substrate is cut by a cutting blade, burrs are generated on the connection terminals, and adjacent connection terminals are short-circuited, thereby deteriorating the quality and reliability of the chip size package (CSP).
[0004]
Further, when a workpiece such as a semiconductor wafer is cut by a cutting blade, not only the CSP substrate, there is also a problem that fine cutting chips adhere to the surface of the workpiece and become contaminated.
As a cutting technique that solves such problems in cutting with a cutting blade, a high-pressure water jet in which abrasive grains such as silica and garnet are mixed into a workpiece held by a workpiece holding mechanism is sprayed from a nozzle. Water jet cutting processing for cutting a workpiece has been proposed. (For example, refer to Patent Document 1.)
[0005]
[Patent Document 1]
JP-A-2002-205298 [0006]
However, the pressure increasing mechanism for increasing the pressure of the processing water includes a cylinder having a large-diameter piston chamber and a small-diameter plunger chamber, a piston disposed in the piston chamber, and a plunger connected to the piston and fitted into the plunger chamber. When the working water is introduced into the plunger chamber and the hydraulic pressure is introduced into the piston chamber, the working water is set to a high pressure due to the difference in the pressure receiving area between the piston and the plunger. In the pressure increasing mechanism having such a configuration, since the pressure in the piston chamber and the pressure in the plunger chamber have a pressure difference corresponding to the difference in the pressure receiving area, the processing water enters the piston chamber from the high-pressure plunger chamber. . However, since fine abrasive grains are mixed in the processing water, the abrasive grains cause the plunger chamber wall and the plunger to wear at an early stage. Therefore, there is a problem that the maintenance of the pressure increasing mechanism must be performed frequently, and the running cost becomes high.
[0007]
In order to solve the above-mentioned problem, the present applicant has divided a machining water delivery means for delivering machining water containing abrasive grains to a nozzle into a cylinder, a first chamber and a second chamber in the cylinder, and divided the cylinder into a first chamber and a second chamber. The first chamber communicates with the high-pressure water generating means and the drainage means, and the second chamber communicates with the processing water storing means and the nozzle. Japanese Patent Application No. 2002-305971 proposes a water jet processing apparatus in which the first chamber and the second chamber of the cylinder have substantially the same pressure during operation.
[0008]
[Problems to be solved by the invention]
Thus, the water jet processing apparatus proposed as Japanese Patent Application No. 2002-305971 introduces processing water containing abrasive grains into the second chamber of the cylinder and causes high-pressure water to act on the first chamber. Since the processing water introduced into the second chamber is jetted from the nozzle, the abrasive grains settle at the bottom of the cylinder forming the second chamber. As a result, there is a problem that the abrasive concentration of the processing water jetted from the nozzle becomes non-uniform, and the processing accuracy is not stable.
[0009]
The present invention has been made in view of the above facts, and its main technical problem is to provide a water jet processing apparatus capable of stabilizing the processing accuracy by making the abrasive concentration of the processing water sprayed from a nozzle uniform. To provide.
[0010]
[Means for Solving the Problems]
In order to solve the main technical problem, according to the present invention, a workpiece holding mechanism that holds a workpiece, a nozzle that jets a water jet to the workpiece held by the workpiece holding mechanism, A processing water supply means for supplying processing water mixed with abrasive grains to the nozzle,
The processing water supply means includes high pressure water generation means, and processing water sending means for sending processing water to the nozzle by high pressure water from the high pressure water generation means,
The processing water delivery means includes a cylinder, and a partition member that divides the inside of the cylinder into a first chamber and a second chamber and is displaceable,
The first chamber is connected to the high-pressure water generating means, and is connected to drainage means for appropriately discharging high-pressure water in the first chamber,
The second chamber is connected to a processing water storage unit that stores processing water, and is also connected to the nozzle.
A processing water stirring means for stirring the processing water in the second chamber;
A water jet processing apparatus is provided.
[0011]
The processing water stirring means includes a stirring water injection nozzle that opens to the second chamber, and a stirring water supply means that supplies stirring water to the stirring water injection nozzle. Further, it is preferable that an outlet of the stirring water injection nozzle is opened toward a bottom wall of a cylinder constituting the second chamber.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a preferred embodiment of a water jet processing apparatus constituted according to the present invention will be described in more detail with reference to the accompanying drawings.
[0013]
FIG. 1 is an exploded perspective view of a part of a water jet processing apparatus configured according to the present invention. The water jet processing apparatus shown in FIG. 1 includes a stationary base 2 and a workpiece holding mechanism 3 that is disposed on the stationary base 2 so as to be movable in a cutting and feeding direction indicated by an arrow X and holds a workpiece. A water jet injection unit support mechanism 4 disposed on the stationary base 2 so as to be movable in an indexing direction indicated by an arrow Y perpendicular to the direction indicated by the arrow X, and an arrow Z provided on the water jet injection unit support mechanism 4. The water jet injection unit 5 is provided so as to be movable in the direction shown by.
[0014]
The workpiece holding mechanism 3 includes a pair of guide rails 31, 31 disposed on the stationary base 2 in parallel along a direction indicated by an arrow X, and an arrow X on the guide rails 31, 31. A first sliding block 32 movably disposed in a direction, a second sliding block 33 movably disposed on the first sliding block 32 in a direction indicated by an arrow Y, and the second sliding block 33. And a base table 36 supported by a cylindrical member 34 on the sliding block 33. The base table 36 is attached to the upper end of a rotating shaft 340 that is disposed so as to pass through the inside of the cylindrical member 34, and is described below of the water jet injection unit 5 by a pulse motor (not shown) provided inside the cylindrical member 34. It is configured to be rotated in a plane perpendicular to the direction of the water jet injected from the nozzle, that is, in a horizontal plane. A detachable table for removably positioning a workpiece is placed and held on the base table 36. Hereinafter, the base table 36 and the detachable table will be described with reference to FIGS.
[0015]
2 is an exploded perspective view showing the detachable table 10, FIG. 3 is a perspective view showing the detachable table 10 and a CSP board 100 as a workpiece, and FIG. 4 shows a state in which the detachable table 10 is held on a base table 36. It is sectional drawing.
First, the base table 36 will be described with reference to FIGS.
The base table 36 in the illustrated embodiment is formed in a rectangular shape including a bottom wall 361, an upper wall 362, and a frame-shaped side wall 363, and includes a negative pressure chamber 360 formed by these walls. At the center of the bottom wall 361 of the base table 36, a negative pressure introducing hole 361a communicating with the negative pressure chamber 360 and a passage 340a provided in the rotating shaft 340 is formed. The passage 340a provided in the rotating shaft 340 is connected to a suction source via a negative pressure control circuit (not shown). The upper wall 362 of the base table 36 is provided with a suction port 362a and a communication hole 362b which communicate with the negative pressure chamber 360 and open on the upper surface serving as a mounting surface. The suction port 362a is formed in the center, and the communication hole 362b is formed on the suction port 362a on the right side in FIG.
[0016]
As shown in FIG. 2, the detachable table 10 in the illustrated embodiment includes a rectangular parallelepiped relief member 11 and a holding tray 12 for holding the relief member 11. The relaxation member 11 is formed of urethane in the illustrated embodiment, and has an upper surface serving as a support surface 11a for supporting a workpiece. In addition, as a material constituting the relaxing member 11, a metal such as stainless steel, tungsten, nickel, and copper, and a ceramic such as alumina can be used in addition to a resin such as urethane. The relaxation member 11 is provided with a plurality of suction holes 11b that are open on the support surface 11a, which is the upper surface, and penetrate the lower surface. The suction holes 11b are formed at positions on the support surface 11a that face the individual chips into which the workpiece is divided.
[0017]
As shown in FIG. 2, the holding tray 12 constituting the attaching / detaching table 10 includes a rectangular bottom wall 121 and a frame-shaped side wall 122 formed to protrude upward from a peripheral edge of the bottom wall 121. It is open. The holding tray 12 is made of a metal material such as stainless steel. A frame-shaped support shelf 121a for placing and supporting the lower surface of the relaxing member 11 is formed around the upper surface of the bottom wall 121 constituting the holding tray 12. A communication hole 121b is formed in the bottom wall 121 of the holding tray 12 at a position corresponding to the communication hole 362b provided in the upper wall 362 of the base table 36. A check valve 123 is provided in the communication hole 121b as shown in FIG. The check valve 123 allows the flow when the negative pressure on the negative pressure chamber 360 side of the base table 36 is high, but shuts off the flow when the negative pressure in the holding tray 12 is high. That is, the check valve 123 allows the negative pressure to flow into the holding tray 12, but shuts off the negative pressure from the holding tray 12. In connection with the check valve 123, an operating rod 124 for opening the function of the check valve 123 is disposed on the bottom wall 121 constituting the holding tray 12. As shown in FIGS. 3 and 4, the lower portion of the relaxation member 11 is fitted to the holding tray 12 configured as described above from the upper opening side. In this fitted state, the periphery of the lower surface of the relaxation member 11 is placed on a frame-shaped support shelf 121 a formed on the bottom wall 121 constituting the holding tray 12. Therefore, a suction chamber 120 is formed between the upper surface of the bottom wall 121 and the lower surface of the relaxation member 11 as shown in FIG. As a result, the plurality of suction holes 11b formed in the relaxation member 11 communicate with the suction chamber 120.
[0018]
In the detachable table 10 configured as described above, the workpiece 100 such as the CSP board is placed on the support surface 11a which is the upper surface of the relaxation member 11, and as shown in FIG. On the upper surface. In this manner, when the detachable table 10 supporting the workpiece 100 on the support surface 11a of the relaxation member 11 is placed on the base table 36, a negative pressure control circuit (not shown) is controlled and provided on the rotating shaft 340. When the provided passage 340 a is communicated with a suction source (not shown), the suction passage 362 a provided on the bottom wall 361 of the base table 36, the negative pressure chamber 360, and the upper wall 362 of the base table 36 is provided. Negative pressure acts on the lower surface of the holding tray 12 constituting the detachable table 10, and the holding tray 12 is suction-held on the base table 36. On the other hand, when the negative pressure chamber 360 of the base table 36 is connected to the suction source as described above, the negative pressure chamber 360 is provided in the communication hole 362 b provided in the upper wall 362 of the base table 36 and in the bottom wall 121 of the holding tray 12. A negative pressure acts on the lower surface of the workpiece 100 through the check valve 123, the suction chamber 120, and the suction hole 11b provided in the relief member 11 provided in the communication hole 121b. It is held by suction.
[0019]
Returning to FIG. 1 and continuing the description, the first sliding block 32 is provided with a pair of guided grooves 321 fitted on the lower surface thereof so as to be fitted with the pair of guide rails 31, 31. A pair of guide rails 322 and 322 formed in parallel on the upper surface along the direction indicated by arrow Y are provided. The first sliding block 32 configured as described above is configured so that the guided grooves 321, 321 are fitted into the pair of guide rails 31, 31 so that the direction indicated by the arrow X along the pair of guide rails 31, 31. Is configured to be movable. The workpiece holding mechanism 3 in the illustrated embodiment includes first moving means 37 for moving the first sliding block 32 along the pair of guide rails 31, 31 in the direction indicated by the arrow X. I have. The first moving means 37 includes a male screw rod 371 disposed in parallel between the pair of guide rails 31 and 31, and a driving source such as a pulse motor 372 for driving the male screw rod 371 to rotate. I have. One end of the male screw rod 371 is rotatably supported by a bearing block 373 fixed to the stationary base 2, and the other end is power-coupled to the output shaft of the pulse motor 372 via a speed reducer (not shown). ing. The male screw rod 371 is screwed into a female screw hole (not shown) formed in a female screw block (not shown) protruding from the lower surface of the central portion of the first sliding block 32. Therefore, by driving the male screw rod 371 to rotate forward and reverse by the pulse motor 372, the first sliding block 32 is driven along the guide rails 31, 31 by the water jet jetting unit 5, which jets water jets from nozzles to be described later. It is moved in the direction indicated by arrow X in a plane perpendicular to the direction, that is, in a horizontal plane.
[0020]
The second sliding block 33 has a pair of guided grooves 331 and 331 fitted on a lower surface thereof with a pair of guide rails 322 and 322 provided on an upper surface of the first sliding block 32. By fitting the guided grooves 331 and 331 to the pair of guide rails 322 and 322, the guide grooves 331 and 331 can be moved in the direction indicated by the arrow Y. The workpiece holding mechanism 3 in the illustrated embodiment moves the second sliding block 33 in a direction indicated by an arrow Y along a pair of guide rails 322 and 322 provided on the first sliding block 32. A second moving means 38 is provided. The second moving means 38 includes a male screw rod 381 disposed in parallel between the pair of guide rails 322 and 322, and a drive source such as a pulse motor 382 for rotating the male screw rod 381. I have. One end of the male screw rod 381 is rotatably supported by a bearing block 383 fixed to the upper surface of the first sliding block 32, and the other end is connected to an output shaft of the pulse motor 382 via a speed reducer (not shown). Transmission connection. The male screw rod 381 is screwed into a female screw hole (not shown) formed in a female screw block (not shown) protruding from the lower surface of the center of the second sliding block 33. Therefore, by driving the male screw rod 381 to rotate forward and reverse by the pulse motor 382, the second sliding block 33 is moved along the guide rails 322 and 322 in the index feed direction indicated by the arrow Y perpendicular to the arrow X. .
[0021]
Bellows means 391 and 392 are provided on both sides of the support table 35 in the direction indicated by the arrow X, and each component other than the base table 36 constituting the workpiece holding mechanism 3 is provided by the bellows means 391 and 392. Covered. Opposing ends of the bellows means 391 and 392 are attached to the support table 35, respectively. Both end portions of the bellows means 391 and 392 are attached to the inner end walls 393a and 393b of the frame-shaped drain gutter means 393 disposed on the stationary base 2 by surrounding the workpiece holding mechanism 3. .
[0022]
The water jet injection unit support mechanism 4 includes a pair of guide rails 41, 41 disposed on the stationary base 2 in parallel along the index feed direction indicated by the arrow Y, and arrows on the guide rails 41, 41. The movable support base 42 is provided so as to be movable in the direction indicated by Y. The movable support base 42 includes a movable support portion 421 movably disposed on the guide rails 41, 41, and a mounting portion 422 attached to the movable support portion 421. The mounting portion 422 is provided with a pair of guide rails 422a and 422a extending in a direction indicated by an arrow Z on one side surface in parallel. The water jet injection unit support mechanism 4 in the illustrated embodiment is a third moving means for moving the movable support base 42 along the pair of guide rails 41, 41 in the direction indicated by the arrow Y which is the indexing feed direction. 43. The third moving means 43 includes a male screw rod 431 arranged in parallel between the pair of guide rails 41, 41, and a drive source such as a pulse motor 432 for driving the male screw rod 431 to rotate. I have. One end of the male screw rod 431 is rotatably supported by a bearing block (not shown) fixed to the stationary base 2, and the other end is transmission-coupled to the output shaft of the pulse motor 432 via a speed reducer (not shown). Have been. The male screw rod 431 is screwed into a female screw hole (not shown) formed in a female screw block (not shown) protruding from the lower surface of the central part of the movable support part 421 constituting the movable support base 42. Therefore, by driving the male screw rod 431 to rotate forward and reverse by the pulse motor 432, the movable support base 42 is moved along the guide rails 41, 41 in the indexing feed direction indicated by the arrow Y.
[0023]
The water jet injection unit 5 in the illustrated embodiment includes a unit holder 51 and a water jet injection unit 52 attached to the unit holder 51. The unit holder 51 is provided with a pair of guided grooves 51a, 51a that are slidably fitted to a pair of guide rails 422a, 422a provided on the mounting portion 422. The guided grooves 51a, 51a By being fitted to the guide rails 422a and 422a, it is movably supported in the direction indicated by the arrow Z. The water jet injection unit 5 in the illustrated embodiment includes a fourth moving unit 53 for moving the unit holder 51 along the pair of guide rails 422a and 422a in the direction indicated by the arrow Z. The fourth moving means 53, like the first to third moving means, has a male screw rod (not shown) disposed between the pair of guide rails 422a and 422a, and rotationally drives the male screw rod. A drive source such as a pulse motor 532 for driving the unit holder 51 and the water jet injection means 52 along the guide rails 422a and 422a by driving a male screw rod (not shown) in the forward and reverse directions by the pulse motor 532. Move in the direction indicated by arrow Z.
[0024]
The water jet injection means 52 includes a nozzle 522 disposed at the tip of a cylindrical casing 521 fixed to the unit holder 51 and extending substantially horizontally. The nozzle 522 will be described with reference to FIG.
The nozzle 522 shown in FIG. 5 includes a nozzle main body 522a, a passage 522b formed in the nozzle main body 522a, and an injection hole 522c having a diameter of 30 to 100 μm which communicates with the passage 522b and opens on the lower surface. In the nozzle 522 thus configured, a processing water introduction passage 522d communicating with the passage 522b is provided above the nozzle body 522a, and a clean water introduction passage communicating with the passage 522b at an intermediate portion of the nozzle body 522a. 522e is provided. A processing water supply unit described later is connected to the processing water introduction passage 522d, and a clean water supply unit described below is connected to the clean water introduction passage 522e.
[0025]
Next, the processing water supply means 6 and the clean water supply means 7 will be described with reference to FIG.
The processing water supply means 6 shown in FIG. 6 includes a water tank 61, high-pressure water generation means 62, processing water storage means 63, and processing water delivery means 64. The water tank 61 contains fresh water such as tap water or pure water. The high-pressure water generating means 62 pressurizes the water supplied from the water tank 61 to 300 to 500 megapascals (MPa), and supplies the water to the processing water sending means 64.
[0026]
The processing water storage unit 63 includes a processing water storage tank 631 and a pressurizing unit 632 that pressurizes processing water stored in the processing water storage tank 631. The processing water storage tank 631 stores processing water in which fine abrasive grains such as silica and garnet are mixed in water. The pressurizing means 632 is disposed on the air pump 633, a pressurizing pipe 634 that communicates the air pump 633 with an air inlet formed on the upper wall of the processing water storage tank 631, and the pressurizing pipe 634. And a switched electromagnetic switching valve 635.
[0027]
The processing water sending means 64 includes a first processing water sending means 64a and a second processing water sending means 64b in the illustrated embodiment. The first working water delivery means 64a and the second working water delivery means 64b are respectively slid into the first cylinder 641a and the second cylinder 641b and into the first cylinder 641a and the second cylinder 641b, respectively. There is provided a first piston 644a and a second piston 644b which are disposed so as to be able to partition the inside of the cylinder into first chambers 642a and 642b and second chambers 643a and 643b. Note that a diaphragm that partitions the inside of the cylinder into a first chamber and a second chamber may be used instead of the first piston 644a and the second piston 644b. That is, the piston and the diaphragm which divide the inside of the cylinder into the first chamber and the second chamber function as a partition member which divides the inside of the cylinder into the first chamber and the second chamber and can be displaced by the pressure of both chambers. I do.
[0028]
The first chambers 642a and 642b of the first cylinder 641a and the second cylinder 641b constituting the first processing water delivery means 64a and the second processing water delivery means 64b are connected via high-pressure pipes 651a and 651b, respectively. The high-pressure water generating means 62 is in communication with the high-pressure water generating means 62. The high pressure pipes 651a and 651b are provided with electromagnetic switching valves 661a and 661b, respectively. Further, the first chambers 642a and 642b of the first cylinder 641a and the second cylinder 641b are connected to the drainage means 67, respectively. The drainage means 67 is provided at a vacuum pump 671 as a suction means, at drainage pipes 672a and 672b for communicating the vacuum pump 671 with the first chambers 642a and 642b, respectively, and at the drainage pipes 672a and 672b. And electromagnetic switching valves 673a and 673b.
[0029]
The second chambers 643a and 643b of the first cylinder 641a and the second cylinder 641b constituting the first processing water delivery means 64a and the second processing water delivery means 64b are respectively connected via introduction pipes 652a and 652b. The processing water storage tank 631 communicates with the processing water storage tank 631. Electromagnetic switching valves 662a and 662b are provided in the introduction pipes 652a and 652b, respectively. The second chambers 643a and 643b of the first cylinder 641a and the second cylinder 641b are connected to the processing water introduction passage 522d of the nozzle 522 via delivery pipes 653a and 653b, respectively. Electromagnetic switching valves 663a and 663b are provided in the delivery pipes 653a and 653b, respectively.
[0030]
Next, the clean water supply means 7 will be described.
The clean water supply means 7 shown in FIG. 6 includes a clean water pipe 71 communicating the high pressure pipe 651a and the clean water introduction passage 522e of the nozzle 522, and an electromagnetic switching valve 72 provided in the clean water pipe 71. Has become. When the electromagnetic switching valve 72 is energized, the high-pressure water generated by the high-pressure water generating means 62 is introduced into the nozzle 522 through the clean water pipe 71.
[0031]
Continuing the description with reference to FIG. 6, the water jet processing apparatus in the illustrated embodiment includes a first cylinder 641a and a second cylinder 641a that constitute the first processing water delivery unit 64a and the second processing water delivery unit 64b. There is provided processing water stirring means 8 for stirring the processing water in the second chambers 643a and 643b of the second cylinder 641b. The processing water stirring means 8 includes stirring water injection nozzles 81a and 81b that open to the second chambers 643a and 643b of the first cylinder 641a and the second cylinder 641b, respectively, and the cleaning water injection nozzles 81a and 81b and the cleaning water. It is composed of stirring water pipes 82a, 82b, 83 communicating with the pipe 71, an electromagnetic switching valve 84a disposed on the stirring water pipe 82a, and an electromagnetic switching valve 84b disposed on the stirring water pipe 82b. The stirring water injection nozzles 81a and 81b are provided to penetrate the bottom walls 645a and 645b of the first cylinder 641a and the second cylinder 641b, respectively. The stirring water injection nozzles 81a and 81b are formed in an inverted U shape, and their outlets 811a and 811b are opened toward the bottom walls 645a and 645b of the first cylinder 641a and the second cylinder 641b, respectively. I have. As described above, the jet ports 811a and 811b of the stirring water jet nozzles 81a and 81b are opened toward the bottom walls 645a and 645b of the first cylinder 641a and the second cylinder 641b, respectively. The abrasive grains mixed into the processing water by the action of the stirring water jetted from 811b do not settle on the bottom walls 645a and 645b. When the electromagnetic switching valves 84a and 84b are energized, they communicate with the stirring water pipes 82a and 82b. As a result, the high-pressure water generated by the high-pressure water generating means 62 is supplied to the clean water pipe 71 and The stirring water is introduced into the stirring water injection nozzles 81a and 81b as stirring water through the stirring water pipes 83, 82a and 82b. Therefore, the high-pressure water generating means 62, the stirring water pipes 83, 82a, 82b and the electromagnetic switching valves 84a, 84b function as stirring water supply means for supplying stirring water to the stirring water injection nozzles 81a, 81b.
[0032]
The processing water supply means 6 and the clean water supply means 7 shown in FIG. 6 are configured as described above, and the operation thereof will be described below.
At the start of the operation of the processing water supply means 6, the high pressure water generation means 62, the vacuum pump 671 and the air pump 633 are operated, and all the electromagnetic switching valves are deenergized (OFF) as shown in FIG. In order to operate the first processing water delivery means 64a from the state shown in FIG. 6, the electromagnetic switching valve 673a of the drainage means 67 is energized (ON) and the electromagnetic switching valve 662a is energized (ON). As a result, the high-pressure water in the first chamber 642a of the first cylinder 641a is sucked into the vacuum pump 671 through the drain pipe 672a and the electromagnetic switching valve 673a, and the processing water in the processing water storage tank 631 is introduced into the introduction pipe 652a. Then, it is introduced into the second chamber 643a of the first cylinder 641a through the electromagnetic switching valve 662a, and the first piston 644a is moved upward in FIG.
[0033]
When the first piston 644a reaches, for example, 70 to 80% of the upper position indicated by the two-dot chain line in FIG. 6, the electromagnetic switching valve 662a is deenergized (OFF). Next, the electromagnetic switching valve 84a is energized (ON) to eject high-pressure water from the agitated water injection nozzle 81a toward the bottom wall of the second chamber 643a as agitated water, thereby entering the second chamber 643a. The processing water mixed with the introduced abrasive grains is stirred. In this way, the stirring water is introduced into the second chamber 643a of the first cylinder 641a, and when the first piston 644a reaches the upper position shown by the two-dot chain line in FIG. 6, the electromagnetic switching valve 673a and the electromagnetic switching valve 84a is deenergized (OFF). Then, the electromagnetic switching valve 663a is energized (ON), and the electromagnetic switching valve 661a is energized (ON). Accordingly, the high-pressure water generated by the high-pressure water generating means 62 is introduced into the first chamber 642a of the first cylinder 641a through the high-pressure pipe 651a and the electromagnetic switching valve 661a, and moves the first piston 644a downward in FIG. Press to make sure. As a result, the processing water in the second chamber 643a of the first cylinder 641a is introduced into the nozzle 522 through the delivery pipe 653a and the electromagnetic switching valve 663a, and is jetted as a water jet from the jet hole 522c. Then, when the first piston 644a of the first cylinder 641a reaches the lower position shown by the solid line in FIG. 6, the electromagnetic switching valve 661a is deenergized (OFF) and the electromagnetic switching valve 663a is deenergized (OFF). This returns to the state shown in FIG. The processing water introduced into the second chamber 643a of the first cylinder 641a as described above is stirred by the agitating water jetted into the second chamber 643a after the introduction, and is thus sent out from the second chamber 643a. The processing water to be used has a uniform abrasive grain concentration. Accordingly, the abrasive concentration of the processing water injected as a water jet from the injection hole 522c of the nozzle 522 becomes uniform, and the processing accuracy can be stabilized.
[0034]
Next, the operation of the second processing water delivery means 64b will be described.
In the state shown in FIG. 6, the second piston 644b constituting the second processing water delivery means 64b moves to the upper position shown by the solid line, and the processing water is introduced into the second chamber 643b of the second cylinder 641b. It is in a state where it is. In this state, similarly to the operation of the first processing water delivery means 64a, the electromagnetic force is applied when the second piston 644b reaches, for example, 70 to 80% of the upper position indicated by the solid line in FIG. The switching valve 662b is deenergized (OFF), the electromagnetic switching valve 84b is energized (ON), and high-pressure water is jetted from the agitated water injection nozzle 81b toward the bottom wall of the second chamber 643b as agitated water. The processing water mixed with the abrasive grains introduced into the second chamber 643b is stirred. When the stirring water is introduced into the second chamber 643b of the second cylinder 641b, and the second piston 644b reaches the upper position shown by the solid line in FIG. 6, the electromagnetic switching valve 673b and the electromagnetic switching valve 84b are switched off. It is de-energized (OFF). Then, when the electromagnetic switching valve 663b is energized (ON) and the electromagnetic switching valve 661b is energized (ON), the high-pressure water generated by the high-pressure water generating means 62 passes through the high-pressure pipe 651b and the electromagnetic switching valve 661b to the second cylinder. The piston 644b is introduced into the first chamber 642b of the chamber 641b and presses the piston 644b to move downward in FIG. As a result, the processing water in the second chamber 643b of the second cylinder 641b is introduced into the nozzle 522 through the delivery pipe 653b and the electromagnetic switching valve 663b, and is injected as a water jet from the injection hole 522c. Note that the processing water introduced into the second chamber 643b of the second cylinder 641b is stirred by the stirring water jetted into the second chamber 643b after the introduction as described above. The processing water delivered from 643b has a uniform abrasive grain concentration. Therefore, the abrasive concentration of the processing water sprayed as a water jet from the injection hole 522c of the nozzle 522 becomes uniform, and the processing accuracy can be stabilized.
[0035]
As described above, when the piston 644b of the second cylinder 641b reaches the lower position indicated by the two-dot chain line in FIG. 6, the electromagnetic switching valve 84b is deenergized (OFF) and the electromagnetic switching valve 661b is deenergized (OFF). At the same time, the electromagnetic switching valve 663b is deenergized (OFF). Next, when the electromagnetic switching valve 673b is energized (ON) and the electromagnetic switching valve 662b is energized (ON), the high-pressure water in the first chamber 642b of the second cylinder 641b drains the drainage pipe 672b and the electromagnetic switching valve 673b. And the processing water in the processing water storage tank 631 is introduced into the second chamber 643b of the second cylinder 641b through the introduction pipe 652b and the electromagnetic switching valve 662b, and the piston 644b is moved in FIG. It is moved upward. Then, when the second piston 644b reaches, for example, 70 to 80% up to the upper position indicated by the solid line in FIG. 6, the electromagnetic switching valve 662b is deenergized (OFF), and the electromagnetic switching valve 84b is energized (ON). Then, high-pressure water is ejected from the agitated water injection nozzle 81b toward the bottom wall of the second chamber 643b as agitated water, and the processing water containing abrasive grains introduced into the second chamber 643a is agitated. You.
[0036]
By alternately operating the first processing water delivery means 64a and the second processing water delivery means 64b described above, processing water can be continuously injected from the injection holes 522c of the nozzle 522. The first processing water delivery means 64a and the second processing water delivery means 64b which send out the processing water to the nozzle 522 are provided with a first chamber 642a, a second chamber 643a and a second chamber 643a of the first cylinder 641a during the operation thereof. Since the first chamber 642b and the second chamber 643b of the cylinder 641b have substantially the same pressure and do not generate a pressure difference, the processing water in the second chamber 643a and the second chamber 643b is removed from the first chamber 642a and the first chamber 642b. Does not enter the chamber 642b. Therefore, wear of the cylinder walls of the first cylinder 641a and the second cylinder 641b and the first piston 644a and the second piston 644b due to the abrasive mixed in the processing water is reduced.
[0037]
In the illustrated embodiment, an example is shown in which a drain pump 65 is provided with a vacuum pump 671 as a suction unit, and a pressurizing unit 632 for pressurizing processing water stored in a processing water storage tank 631 is provided. However, either one of the vacuum pump 671 and the pressurizing unit 632 may be used. For example, when the vacuum pump 671 is provided and the pressurizing unit 632 is not provided, the processing water storage tank 631 is opened to the atmosphere. In this case, the electromagnetic switching valve 662a provided in the introduction pipes 652a and 652b that communicate the processing water storage tank 631 with the second chamber 643a of the first cylinder 641a and the second chamber 643b of the second cylinder 641b. And 662b may be check valves that allow the flow from the processing water storage tank 631 to the first and second cylinders 641a and 641b, but block the flow in the opposite direction. On the other hand, when the pressurizing means 632 is provided and the vacuum pump 671 is not provided, the vacuum pump 671 side from the electromagnetic switching valves 673a and 673b in the drainage pipes 672a and 672b is opened to the atmosphere.
[0038]
Next, the operation of the clean water supply means 7 will be described with reference to FIG.
As described above, when the water jet operation by the processing water supply means 6 is completed, all the electromagnetic switching valves are deenergized (OFF). Then, when the electromagnetic switching valve 72 is energized (ON), the high-pressure water generated by the high-pressure water generating means 62 is introduced into the clean water introduction passage 522 e of the nozzle 522 through the clean pipe 71 and the electromagnetic switching valve 72. As a result, at the end of the water jet operation, the processing water mixed with the abrasive grains remaining in the passage 522b of the nozzle 522 is discharged together with the high-pressure water through the injection hole 522c, and the delivery pipe 653a, It is pushed back to the 653b side. It is desirable that the electromagnetic switching valves 663a and 663b be energized (ON) when high-pressure water is introduced into the nozzle 522, so that the processing water mixed with abrasive particles remaining in the passage 522b of the nozzle 522. Can be returned to the first and second cylinders 641a and 641b. When the introduction of the high-pressure water to the nozzle 522 is stopped, the electromagnetic switching valves 663a and 663b are deenergized (OFF). Accordingly, since only fresh water remains in the nozzle 522, even if the operation is stopped and left, the abrasive grains mixed in the processing water do not settle and clog the injection holes 522c.
In the illustrated embodiment, the clean water supply unit 7 is configured to introduce the high-pressure water generated by the high-pressure water generation unit 62 to the nozzle 522. However, the clean water supply unit 7 supplies the clean water to the nozzle 522. Means may be separately provided. In this case, the water supply pump for supplying the clean water may supply the clean water at a pressure of about 1 to 10 megapascals (MPa).
[0039]
Returning to FIG. 1, the description is continued, and an imaging unit 9 is disposed at a front end of a casing 521 that constitutes the water jet injection unit 52. The image pickup means 9 is constituted by a microscope, a CCD camera, or the like for picking up an image of a street or the like formed on a workpiece such as a CSP board, and sends a picked-up image signal to a control means (not shown).
[0040]
The water jet processing apparatus in the illustrated embodiment is configured as described above, and the cutting operation will be described below mainly with reference to FIG.
With the base table 36 constituting the workpiece holding mechanism 3 positioned at the position shown in FIG. 1, the holding tray 12 of the detachable table 10 is suction-held on the base table 36 as described above, The workpiece 100 is suction-held on the support surface 11a. Next, the base table 36 and the attachment / detachment table 10 are moved along the guide rails 31 by the operation of the first moving means 37, and are positioned immediately below the imaging means 9.
[0041]
As described above, when the base table 36 and the attachment / detachment table 10 are positioned directly below the imaging unit 9, a street formed on the workpiece 100 held on the attachment / detachment table 10 by the imaging unit 9 and a control unit (not shown); Image processing such as pattern matching for alignment with the nozzle 522 of the water jet injection unit 5 that jets a water jet along the street is performed, and alignment of the water jet injection position is performed.
[0042]
After the alignment is performed as described above, the base table 36 and the detachable table 10 are moved to the cutting area where the nozzle 522 of the water jet injection unit 5 is located, and the processing water supply unit 6 is operated as described above. Then, high-pressure processing water is jetted as a water jet from the injection hole 522c of the nozzle 522 along the street of the workpiece 100 detected as described above in the cutting area, and cut along the street. In this cutting operation, the water jet penetrates the workpiece 100 at the time of cutting, but the cut water jet is received by the relaxation member 11 of the detachable table 10 and its momentum is reduced. Since the relaxation member 11 is gradually damaged by the action of the water jet, the relaxation member 11 is replaced after being used a predetermined number of times. The water whose power has been reduced after the cutting action falls from the bellows means 391 and 392 and flows to the frame-shaped drain gutter means 393.
[0043]
After cutting along the predetermined street as described above, the cutting operation is performed by indexing and feeding the base table 36 and the detachable table 10 in the indexing direction indicated by the arrow Y at intervals of the street. The indexing feed of the base table 36 and the attachment / detachment table 10 is performed by the second moving means 38 constituting the workpiece holding mechanism 3. Note that the index feed may be performed by the third moving unit 43 constituting the water jet injection unit support mechanism, but it is preferable to move the base table 36 because it affects the high-pressure water generating unit 62. When the cutting operation and the indexing operation are performed for all the streets extending in the predetermined direction in this way, the base table 36 and the detachable table 10 are rotated by 90 degrees, and each of the streets extending perpendicular to the predetermined direction is rotated. By executing the cutting operation and the indexing operation along the street, the workpiece 100 held on the detachable table 10 is divided into individual chips.
[0044]
When the workpiece 100 is divided into individual chips in this manner, the detachable table 10 and the base table 36 holding the workpiece 100 are returned to the positions shown in FIG. And the suction source is disconnected. As a result, the suction holding of the detachable table 10 on the base table 36 is released. On the other hand, since the check valve 123 is provided in the communication hole 121b formed in the bottom wall 121 of the holding tray 12 constituting the attachment / detachment table 10, even if the communication with the suction source is cut off, the suction chamber 120 is kept open. It is maintained in a negative pressure state. As a result, the suction holding of the workpiece 100 by the detachable table 10 is maintained. At this time, the workpiece 100 is divided into individual chips, but the plurality of suction holes 11b provided in the relaxation member 11 are located on the support surface 11a at positions facing the individual chips into which the workpiece is divided. The suction holding is maintained even in the state of the chip. Therefore, the individual chips into which the workpiece 100 has been divided can be transported to a predetermined place while being suction-held on the detachable table 10. When each chip transported while being suction-held on the detachable table 10 is to be removed, the check rod 123 is opened by pushing the operating rod 124 disposed on the holding tray 12, and the inside of the suction chamber 120 becomes large. The air pressure is reached and the suction holding of each chip is released.
[0045]
When the processing operation is completed as described above, the high-pressure water generated by the high-pressure water generation unit 62 is introduced into the nozzle 522 by operating the clean water supply unit 7 as described above, and remains in the nozzle 522. The processing water mixed with the abrasive grains is discharged together with the high-pressure water through the injection holes 522c, and is pushed back to the delivery pipes 653a and 653b by the pressure of the high-pressure water.
[0046]
【The invention's effect】
Since the water jet processing apparatus according to the present invention is configured as described above and includes the processing water stirring means for stirring the processing water in the second chamber of the cylinder constituting the processing water supply means of the processing water supply means, Since the processing water introduced into the second chamber is agitated, the abrasive mixed in the processing water does not settle, and the processing water delivered from the second chamber has a uniform abrasive particle concentration. Therefore, the abrasive concentration of the processing water jetted as a water jet from the nozzle becomes uniform, and the processing accuracy can be stabilized.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing a part of a water jet processing apparatus configured according to the present invention.
FIG. 2 is an exploded perspective view showing a relaxation member and a holding tray constituting a detachable table used in the water jet processing apparatus shown in FIG. 1;
FIG. 3 is a perspective view showing a detachable table and a workpiece to be used in the water jet processing apparatus shown in FIG. 1;
FIG. 4 is a sectional view showing a state in which the detachable table shown in FIG. 3 is held on a base table.
FIG. 5 is a sectional view of a nozzle for jetting a water jet used in the water jet processing apparatus shown in FIG.
6 is a fluid circuit diagram of processing water supply means provided in the water jet processing apparatus shown in FIG.
[Explanation of symbols]
2: Stationary base 3: Workpiece holding mechanism 31: Guide rail 32: First sliding block 33: Second sliding block 35: Support table 36: Base table 4: Water jet injection unit support mechanism 41: Guide rail 42: movable support base 5: water jet injection unit 51: unit holder 52: water jet injection means 522: nozzle 53: fourth moving means 6: processing water supply means 61: water tank 62: high pressure water generation means 63: Processing water storage means 631: Processing water storage tank 632: Pressurizing means 633: Air pump 64: Processing water delivery means 64a: First processing water delivery means 641a: First cylinder 644a: First piston 64b: Second Processing water delivery means 641b: second cylinder 644b: first piston 7: clean water supply means 8: processing water stirring Stage 9: imaging means 10: detachable Table 11: relaxation member 12: holding trays 100: workpiece

Claims (3)

A workpiece holding mechanism for holding the workpiece, a nozzle for jetting a water jet to the workpiece held by the workpiece holding mechanism, and processing water for supplying processing water containing abrasive grains to the nozzle Supply means, and a water jet processing apparatus comprising:
The processing water supply means includes high pressure water generation means, and processing water sending means for sending processing water to the nozzle by high pressure water from the high pressure water generation means,
The processing water delivery means includes a cylinder, and a partition member that divides the inside of the cylinder into a first chamber and a second chamber and is displaceable,
The first chamber is connected to the high-pressure water generating means, and is connected to drainage means for appropriately discharging high-pressure water in the first chamber,
The second chamber is connected to a processing water storage unit that stores processing water, and is also connected to the nozzle.
A processing water stirring means for stirring the processing water in the second chamber;
A water jet processing apparatus characterized by the above-mentioned. 2. The water jet processing according to claim 1, wherein said processing water stirring means comprises a stirring water injection nozzle opened to said second chamber, and a stirring water supply means for supplying stirring water to said stirring water injection nozzle. apparatus. The water jet processing apparatus according to claim 1, wherein an outlet of the stirring water injection nozzle is opened toward a bottom wall of a cylinder that forms the second chamber.

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