JP2018043308A - Cutting device - Google Patents

Abstract

An object of the present invention is to provide a cutting device having a non-contact set-up mechanism capable of preventing dirt from adhering to an optical sensor while suppressing the amount of cleaning water used. A cutting table includes a chuck table for holding a workpiece, a cutting unit for cutting the workpiece with a cutting blade, a detecting means for detecting a tip position of the cutting blade, and a control means for controlling these. The detection means comprises a U-shaped blade intrusion portion 63, a light emitting portion 64 disposed on one side of the blade intrusion portion, and a light receiving portion 64 for light from the light emitting portion disposed on the other side. A cleaning water nozzle 68 for supplying cleaning water to the end surfaces of the light emitting unit and the light receiving unit to prevent the attachment of cutting chips to the end surfaces; and an air supply nozzle 70 for supplying air to the end surfaces. When detecting, the supply of cleaning water and air from the cleaning water supply nozzle and air supply nozzle is stopped, and at other times, the cleaning water and air are intermittently supplied to the end face to remove cutting chips attached Remove . [Selection diagram] FIG.

Description

  The present invention relates to a cutting device, and more particularly to a cutting device capable of preventing contamination of an optical sensor while suppressing supply of cleaning water to the optical sensor of a non-contact setup mechanism.

  Various electronic components that require precision cutting, such as semiconductor wafers, ceramics, and glass, are divided into individual chips by a cutting device called a dicing saw. The processing of these electronic components requires precise cutting in micron units, and not only the chip size but also the cutting depth is important.

  For example, a semiconductor wafer is fixed to a dicing tape, and a cutting blade is cut into the dicing tape by about 10 to 30 μm to completely cut the semiconductor wafer. However, if the cutting amount into the dicing tape is not sufficient, the wafer is incompletely cut. Thus, the cut piece on the lower side is in a jagged state as if it were missing.

  Further, the cutting blade used for cutting has a property of being worn as cutting is continued, and it is necessary to compensate for variations in the cutting depth due to wear of the cutting blade as needed.

  Such variation in the cutting edge position of the cutting blade is detected at any time by a non-contact setup mechanism using an optical sensor, and correction of the height position of the cutting blade (origin position correction) is performed based on the detection result (for example, JP, 11-214334, A). With this technique, the height position of the cutting blade can be easily detected without damaging the cutting blade without cutting the chuck table for holding the workpiece or the workpiece.

  What is important in the detection of the cutting edge position (tip position) of the cutting blade by the optical sensor is to keep the optical sensor composed of the light emitting part and the light receiving part clean in order to avoid erroneous recognition of the optical sensor. However, since the optical sensor is in the atmosphere of the processing chamber, there is a problem that cutting waste in the atmosphere tends to adhere to the optical sensor and cause erroneous recognition.

  Therefore, a method has been devised in which cleaning water is supplied to the optical sensor except during the operation of detecting the tip position of the cutting blade, but there is a problem that a large amount of cleaning water is consumed. In order to avoid this problem, Japanese Patent Application Laid-Open No. 2003-212354 proposed a method in which the optical sensor is accommodated with an opening / closing lid to prevent the optical sensor from being exposed to the atmosphere of the processing chamber.

JP-A-11-214334 JP 2003-2111354 A

  However, in the mechanism disclosed in Patent Document 2, when a large amount of cutting waste is contained in the atmosphere of the processing chamber, a slight gap between the opening and closing lids may cause contamination of the optical sensor, which may cause false detection. It was left.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a cutting with a non-contact setup mechanism capable of preventing the adhesion of dirt to the optical sensor while suppressing the amount of cleaning water used. Is to provide a device.

  According to the present invention, a chuck table that holds a workpiece, a cutting unit that cuts the workpiece held on the chuck table with a cutting blade, a detection unit that detects a tip position of the cutting blade, and at least the A cutting apparatus comprising a chuck table, a control unit for controlling the cutting unit, and the detection means, the detection means being disposed on a U-shaped blade intrusion portion and one side of the blade intrusion portion. The light emitting unit, the light receiving unit disposed on the other side of the blade penetrating unit that receives light from the light emitting unit, and supplying cleaning water to the end surfaces of the light emitting unit and the light receiving unit A cleaning water nozzle for preventing attachment of cutting waste, and the control means stops the supply of cleaning water from the cleaning water supply nozzle during the detection operation for detecting the tip position of the cutting blade, and Other than detection operation Standby is cutting apparatus and removing the cutting chips adhered to intermittently supplied to the end face of the washing water to the end face is provided.

  Preferably, the detection means further includes an air supply nozzle that supplies air to the light emitting portion and the end face of the light receiving portion, and the control means intermittently supplies air from the air supply nozzle to the end face during the standby time. The cutting waste adhering to the end face is removed by two fluids consisting of water and air.

  According to the cutting device of the present invention, by supplying cleaning water intermittently to the optical sensor of the non-contact setup mechanism, it is possible to prevent dirt from adhering to the optical sensor while suppressing the amount of cleaning water used.

It is a perspective view of the cutting device provided with the non-contact setup mechanism of the present invention. It is a cross-sectional view of the processing chamber casing in a state where the chuck table is moved to the cutting position. It is a longitudinal cross-sectional view of a processing chamber casing. It is a block diagram of a non-contact setup mechanism. It is a graph which shows the change of the output voltage of a non-contact setup mechanism according to the position of the cutting direction of a cutting blade. It is a perspective view of a non-contact setup mechanism. It is a side view of a non-contact setup mechanism. It is explanatory drawing explaining transition of the supply method of washing water.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Referring to FIG. 1, there is shown a perspective view of a cutting device 2 provided with a non-contact setup mechanism (blade end detection mechanism) according to an embodiment of the present invention.

  Reference numeral 4 denotes a base of the cutting apparatus 2. A chuck table 6 is rotatable on the base 4 and is reciprocally movable in the X-axis direction by a processing feed means (not shown). A water cover 8 is disposed around the chuck table 6, and a bellows 10 is connected across the water cover 8 and the base 4 to protect the shaft portion of the processing feed mechanism.

  A gate-shaped column 12 is erected on the rear side of the base 4. A pair of guide rails 14 extending in the Y-axis direction are fixed to the column 12. A Y-axis moving block 16 is mounted on the column 12 so as to be movable in the Y-axis direction along the guide rail 14 by a Y-axis moving mechanism (index feed mechanism) 20 including a ball screw 18 and a pulse motor (not shown). .

  A pair of guide rails 22 extending in the Z-axis direction are fixed to the Y-axis moving block 16. On the Y-axis movement block 16, a Z-axis movement block 24 is mounted on the Y-axis movement block 16 so as to be guided in the guide rail 22 by a Z-axis movement mechanism 30 including a ball screw 26 and a pulse motor 28 so as to be movable in the Z-axis direction.

  A cutting unit 32 is attached to the Z-axis moving block 24, and a spindle 36 shown in FIG. 4 is rotatably accommodated in a spindle housing 34 of the cutting unit 32, and a cutting blade 38 is provided at the tip of the spindle 36. Removably attached. An imaging unit 40 having a microscope and a camera is further attached to the Z-axis moving block 24.

  Reference numeral 42 denotes a processing chamber casing that defines the processing chamber 44, and is formed of a transparent resin such as polycarbonate. The processing chamber casing 42 accommodates the chuck table 6 and the cutting blade 38. An exhaust port 50 is formed in the processing chamber casing 42.

  Reference numeral 46 denotes a non-contact setup mechanism (blade end detection mechanism) according to an embodiment of the present invention, the details of which are shown in FIGS. By pulling the handle 48, the door 49 of the processing chamber casing 42 can be opened, and the workpiece can be loaded onto the chuck table 6, or the workpiece can be unloaded from the chuck table 6.

  Referring to FIG. 2, a cross-sectional view of the processing chamber casing 42 with the chuck table 6 moved to the cutting position is shown. FIG. 3 is a longitudinal sectional view of the processing chamber casing 42. During cutting of the workpiece held on the chuck table 6, cutting water is supplied from the cutting water nozzle 54 toward the blade tip, and the cooling water nozzle 52. Then, the workpiece is cut while supplying cooling water toward the machining point of the cutting blade 38.

  Accordingly, machining waste, mist 56 of cutting water and cooling water scatters in the atmosphere of the processing chamber 44, and the non-contact setup mechanism 46 is exposed to such an atmosphere.

  Next, the non-contact setup mechanism (blade end detection mechanism) 46 according to the embodiment of the present invention will be described in detail with reference to FIGS. As shown in FIG. 6, a columnar bracket 60 protrudes from the base 4, and the attachment member 62 of the non-contact setup mechanism 46 is fixed to the bracket 60. The attachment member 62 has a horizontal portion 62a, a vertical portion 62b that defines a U-shaped blade intrusion portion 63, and an inclined portion 62c.

  An optical sensor 65 including a light emitting portion 64 and a light receiving portion 66 that receives light from the light emitting portion 64 is disposed with the blade intrusion portion 63 interposed therebetween (see FIG. 7). As shown in FIG. 4, the light emitting unit 64 is connected to the light source 84 through the optical fiber 83, and the light receiving unit 66 is connected to the photoelectric conversion unit 86 through the optical fiber 85.

  The inclined portion 62c of the mounting member 62 supplies cleaning water supply nozzles 68 for supplying cleaning water whose temperature is adjusted to the end surfaces of the light emitting unit 64 and the light receiving unit 66, and supplies air to the end surfaces of the light emitting unit 64 and the light receiving unit 66. An air supply nozzle 70 is provided.

  As shown in FIG. 4, the cleaning water supply nozzle 68 is selectively connected to a cleaning water supply source 78 via an electromagnetic switching valve 76, and the air supply nozzle 70 is selected as an air supply source 82 via an electromagnetic switching valve 80. Connected.

  At the time of setting up the cutting blade 38 using the non-contact setup mechanism 46, the pulse motor 28 of the Z-axis feed mechanism 30 is driven so that the tip portion (blade edge) of the cutting blade 38 becomes the blade entry portion 63 of the non-contact setup mechanism 46. Let it invade from above.

  At this time, when the cutting blade 38 does not block between the light emitting part 64 and the light receiving part 66 of the optical sensor 65, the light quantity received by the light receiving part 66 is the maximum, and the photoelectric conversion part corresponding to this light quantity. The output from 86 is set to 5 V as shown in FIG. 5, for example.

  As the cutting blade 38 enters the blade intrusion portion 63, the amount by which the cutting blade 38 blocks the light beam emitted from the light emitting portion 64 gradually increases, so the amount of light received by the light receiving portion 66 gradually decreases. The output voltage from the photoelectric conversion unit 86 gradually decreases as indicated by reference numeral 87 in FIG.

  When the cutting blade 38 reaches the predetermined positions of the light emitting unit 64 and the light receiving unit 66, the output voltage from the photoelectric conversion unit 86 is set to 3 V, which is a reference voltage, for example. Therefore, when the output voltage of the photoelectric conversion unit 86 reaches 3 V, the voltage comparison unit 90 outputs a signal indicating that the output voltage of the photoelectric conversion unit 86 has reached the reference voltage to the end position detection unit 92.

  The end position detection unit 92 transmits a signal indicating that the reference position has been detected to the pulse motor 28 and stops driving the pulse motor 28. At this time, the end position detector 92 detects the position of the cutting blade 38 in the cutting direction (Z-axis direction) by counting the number of pulses of the pulse motor 28 of the Z-axis feed mechanism 30. The reference position that is the position of the lowest point end of the cutting blade 38 is stored in the memory of the cutting device 2.

  According to the non-contact setup method of the present embodiment, after the workpiece is appropriately cut by the cutting blade 38, the lowest point end detection step is executed, and the lowest of the cutting blade 38 calculated and stored last time. Compared with the position of the point end portion, a wear amount calculation step is performed in which the calculation portion 94 calculates the wear amount (consumption amount) of the cutting blade 38.

  Based on the wear amount of the cutting blade 38 calculated from the wear amount calculating step, the position correcting unit 96 corrects the origin position of the cutting blade 38 in the Z-axis direction. By correcting the origin position, the cutting edge of the cutting blade 38 can be set to the origin position in contact with the upper surface of the frame body of the chuck table 6.

  As described above, the non-contact setup mechanism 46 is always exposed to the atmosphere of the processing chamber 44. Therefore, the end surfaces of the light emitting unit 64 and the light receiving unit 66 of the optical sensor 65 are contaminated by mist, cutting waste, and the like contained in the atmosphere.

  In order to prevent this contamination, in the embodiment of the present invention, cleaning water is supplied from the cleaning water supply nozzle 68 to the end surface of the light emitting unit 64 and the end surface of the light receiving unit 66 except during the detection operation of detecting the tip position of the cutting blade 38. More preferably, the cleaning water and air are intermittently supplied from the cleaning water supply nozzle 68 and the air supply nozzle 70 to the end surface of the light emitting unit 64 and the end surface of the light receiving unit 66, so that the light emitting unit 64 and the light receiving unit are supplied. The dirt adhering to the end face of 66 is removed.

  Hereinafter, this end face cleaning method will be described in detail with reference to FIG. 8 indicates that the cutting edge of the cutting blade 38 is being detected. At this time, the supply of the cleaning water from the cleaning water supply nozzle 68 and the supply of air from the air supply nozzle 70 are stopped.

  Needless to say, when detecting the position of the blade end, the opening / closing lid 72 attached to the attachment member 62 is opened via the hinge 74. When the detection operation is completed, the open / close lid 72 is closed to prevent the light emitting unit 64 and the light receiving unit 66 from being exposed to the atmosphere of the processing chamber 44.

  In FIG. 8, during the cutting of the workpiece indicated by the symbol B for which the detection of the cutting edge of the cutting blade 38 has been completed, cleaning water and air are intermittently supplied toward the end surfaces of the light emitting unit 64 and the light receiving unit 66.

  As shown in the second stage of FIG. 8, C indicated by a dotted line is a supply stop period, and D is a supply period. Therefore, the supply stop period C and the supply period D are alternately repeated during the cutting of the workpiece shown in B. For example, after performing the supply stop period C every 1 to 5 seconds, the supply period D of about 0.1 to 2 seconds is performed.

  Further, as shown in the third stage of FIG. 8, in the supply period D, the supply of the cleaning water from the cleaning water supply nozzle 68 and the supply of air from the air supply nozzle 70 are performed simultaneously. After that, a period for supplying only the cleaning water indicated by F is provided, and the end face is in a dry state during the supply stop period indicated by C, thereby preventing the cutting waste from being easily attached to the end face.

  Here, the supply of air from the air supply nozzle 70 serves to remove dirt attached to the end faces of the light emitting unit 64 and the light receiving unit 66 together with the cleaning water. The air flow rate is adjusted so that the end face does not dry.

  The air may be mixed with the cleaning water after being jetted so that the cleaning water supply nozzle 68 and the air supply nozzle 70 are brought close to each other so that the cleaning effect of the end face is enhanced by mixing with the cleaning water. It may be integrated and mixed with cleaning water and air, and then ejected.

  According to the above-described embodiment, the cleaning water and the air are intermittently supplied to the end surfaces of the light-emitting unit 64 and the light-receiving unit 66 of the non-contact setup mechanism 46, so that the optical sensor 65 is contaminated while suppressing the amount of cleaning water used. Can be prevented.

  In addition to this embodiment, in the supply period D, only water may be supplied to prevent drying while preventing dirt from adhering. Further, immediately before the blade end position detection, air may be supplied from the air supply nozzle 70 to remove the cleaning water adhering to the end surface.

2 Cutting device 6 Chuck table 32 Cutting unit 38 Cutting blade 42 Processing chamber casing 44 Processing chamber 46 Non-contact setup mechanism (blade end detection mechanism)
62 Mounting member 63 Blade entry part 64 Light emitting part 65 Optical sensor 66 Light receiving part 68 Washing water supply nozzle 70 Air supply nozzle 84 Light source 86 Photoelectric conversion part 88 Reference voltage setting part 90 Voltage comparison part 92 End position detection part

Claims (2)

A chuck table for holding a workpiece, a cutting unit for cutting the workpiece held on the chuck table with a cutting blade, a detecting means for detecting a tip position of the cutting blade, at least the chuck table, and the cutting A cutting device comprising a unit and a control means for controlling the detection means,
The detection means includes
A U-shaped blade intrusion portion, a light emitting portion disposed on one side of the blade intrusion portion, a light receiving portion disposed on the other side of the blade intrusion portion for receiving light from the light emitting portion, A cleaning water nozzle that supplies cleaning water to the end surfaces of the light emitting unit and the light receiving unit and prevents the attachment of cutting waste to the end surfaces;
The control means includes
During the detection operation for detecting the tip position of the cutting blade, the supply of the cleaning water from the cleaning water supply nozzle is stopped, and during the standby time other than the detection operation, the cleaning water is intermittently supplied to the end surface. A cutting apparatus for removing cutting waste adhering to the end face. The detection means further includes an air supply nozzle for supplying air to the light emitting portion and the end face of the light receiving portion,
2. The control unit according to claim 1, wherein, during the standby, the air is intermittently supplied from the air supply nozzle to the end surface to remove cutting waste adhering to the end surface with water and air. Cutting equipment.