JP2016159409A - Cutting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cutting device capable of excellently cutting a wafer without generating infeed insufficiency by a cutting blade.SOLUTION: A cutting device (1) includes: a chuck table (12) for holding a wafer (W); cutting means (14) for cutting the wafer by a cutting blade (71); cut-feeding means (13) for relatively cut-feeding the chuck table and the cutting means in an X direction; an index-feeding means (15) for relatively index-feeding the chuck table and the cutting means in a Y direction; and infeed-feeding means (16) for infeed-feeding the cutting blade in a Z direction. The cutting device further includes: a light projection section (93) provided in the cutting means; a light receiving section (95) for receiving measurement light from the light projection section; and a determination section (92) for determining abnormal vibration when light receiving amount in the light receiving section exceeds an allowable value.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a cutting apparatus that cuts a wafer with a cutting blade.

  In the cutting apparatus, various setting information such as the wafer size (outer diameter size), the depth of cut with respect to the wafer, the cutting feed speed, the outer size of the cutting blade, and the spindle rotation speed are set. Then, the alignment mark of the wafer is detected by the alignment, the direction of the division planned line is adjusted to the cutting feed direction, and the index direction is confirmed. Thereafter, the cutting blade is lowered to a height at which the wafer can be cut outside the outer periphery of the wafer, the wafer is cut and fed to the cutting blade, and cutting is started along the scheduled division line.

  However, since not all alignment marks on the wafer are detected in the alignment, the outer periphery of the wafer is not grasped. For this reason, in the cutting process, the cutting blade is lowered at a position that greatly protrudes from the outer periphery of the wafer, and it takes an extra time to cut the outer periphery of the wafer from this position before starting to cut. In order to eliminate this waste, it is conceivable to estimate the outer periphery from the center and outer diameter size of the wafer and to lower the cutting blade near the outer periphery of the wafer. As a method for detecting the center of the wafer, for example, the method of Patent Document 1 is known.

Japanese Patent No. 4485771

  However, in the above method, even if the outer periphery of the wafer can be estimated, the estimated position of the outer periphery of the wafer may not match the actual outer peripheral position. For example, when the wafer outer diameter size is set incorrectly or when a plurality of small diameter wafers are held on the chuck table, the wafer may be cut from directly above when the wafer is lowered. In this case, since the wafer is cut at a cutting feed rate of 100 mm / sec, the cutting load is increased and the cutting blade is consumed violently. The worn cutting blade has a problem that the wafer is cut in a state where the cutting depth is insufficient (hereinafter referred to as insufficient cutting). On the other hand, if the cutting speed is slowed down to avoid wear of the cutting blade, it takes time to cut to a predetermined depth.

  This invention is made | formed in view of this point, and it aims at providing the cutting device which can cut a wafer favorably, without producing the shortage of cut with a cutting blade.

  The cutting apparatus of the present invention includes a chuck table for holding a wafer, a cutting means for cutting the wafer held by the chuck table with a rotatable cutting blade, and the chuck table in the X direction which is a cutting direction of the cutting blade. A cutting feed means for cutting and feeding the cutting means relative to each other, an index feeding means for feeding the chuck table and the cutting means relative to each other in the Y direction perpendicular to the X direction, and the cutting blade to the wafer A cutting apparatus comprising: a cutting feed means for cutting and feeding in the Z direction approaching and separating; and an abnormal vibration detecting means for detecting abnormal vibration of the cutting means, wherein the abnormal vibration detecting means is rotating When the cutting blade is cut into the wafer by the vibration detecting unit for detecting the vibration of the cutting blade and the cutting feed means, the vibration is detected. Comprising a determining unit for determining that abnormal vibration when the output unit exceeds the allowable value vibrations are preset for detecting a.

  According to this configuration, the abnormal vibration is detected when the cutting blade is cut and fed in the Z direction and the vibration of the cutting blade exceeds the allowable value. Abnormal vibration occurs when the wafer is cut directly from directly above, so that the cutting device can recognize the severe wear of the cutting blade. For this reason, when the abnormal vibration is detected, the cutting is stopped, so that the cutting of the wafer is not started in a state where the cutting blade is consumed, and it is possible to prevent the wafer from being insufficiently cut. It is also possible to cut the wafer again by returning the cutting depth to normal by dressing or resetting the cutting blade.

  In the cutting apparatus, the vibration detection unit receives the measurement light projected from the light projecting unit that projects the measurement light and the light projecting unit when the cutting blade cuts into the wafer. A light receiving unit, and the determination unit determines that the vibration is abnormal when the amount of light received by the light receiving unit exceeds a preset allowable value.

  According to the present invention, since the cutting blade is cut and fed in the Z direction and abnormal vibration is detected, the wafer can be cut well without causing insufficient cutting by the cutting blade.

It is a perspective view of the cutting device concerning this embodiment. It is a schematic diagram of the abnormal vibration detection means which concerns on this Embodiment. It is an operation | movement transition diagram of the cutting operation which concerns on this Embodiment. It is explanatory drawing which shows the relationship between the light reception amount and time which concern on this Embodiment. It is explanatory drawing of the setting operation | movement of the tolerance which concerns on this Embodiment. It is a figure which shows the positional relationship of the light projection part and light receiving part which concern on a modification. It is explanatory drawing which shows the relationship between the light reception amount which concerns on a modification, and time.

  Hereinafter, the present embodiment will be described with reference to the accompanying drawings. FIG. 1 is a perspective view of a cutting apparatus according to the present embodiment. Note that the cutting apparatus according to the present embodiment is not limited to the configuration shown in FIG. The present invention is applicable to any cutting apparatus as long as it can cut a wafer using a cutting blade.

  As shown in FIG. 1, the cutting apparatus 1 is configured to cut the wafer W by relatively moving the wafer W held on the chuck table 12 and the cutting means 14. The wafer W is carried into the cutting device 1 while being supported by the ring frame F via the dicing tape T. The wafer W may be a semiconductor wafer such as silicon or gallium arsenide, or may be a ceramic, glass, or sapphire optical device wafer. In addition to a circular wafer, a rectangular package substrate such as a CSP (Chip Size Package) substrate or a QFN (Quad Flat Non-leaded package) may be used.

  On the base 11 of the cutting apparatus 1, a cutting feed means 13 for cutting and feeding the chuck table 12 in the X direction is provided. The cutting feed means 13 includes a pair of guide rails 31 arranged on the base 11 and parallel to the X direction, and a motor-driven X-axis table 32 slidably installed on the pair of guide rails 31. Yes. A nut portion (not shown) is formed on the back side of the X-axis table 32, and a ball screw 33 is screwed to the nut portion. Then, when the drive motor 34 connected to one end of the ball screw 33 is rotationally driven, the chuck table 12 is cut and fed along the pair of guide rails 31 in the X direction that is the cutting direction of the cutting blade 71. .

  On the top of the X-axis table 32, a chuck table 12 that holds the wafer W is provided so as to be rotatable about the Z-axis. A holding surface 21 (see FIG. 2) is formed on the chuck table 12 from a porous ceramic material, and the wafer W is sucked and held by the negative pressure generated on the holding surface 21. Around the chuck table 12, four air-driven clamp portions 22 are provided, and the ring frame F around the wafer W is clamped and fixed from four sides by each clamp portion 22. On the upper surface of the base 11, a gate-shaped standing wall portion 81 is provided so as to straddle the movement path of the chuck table 12.

  The standing wall portion 81 is provided with an index feeding means 15 for feeding the cutting means 14 in the Y direction and a cutting feed means 16 for cutting and feeding the cutting means 14 in the Z direction. The index feeding means 15 has a pair of guide rails 51 arranged in front of the standing wall portion 81 and parallel to the Y direction, and a Y-axis table 52 slidably installed on the pair of guide rails 51. The cutting feed means 16 has a pair of guide rails 61 arranged on the Y-axis table 52 and parallel to the Z direction, and a Z-axis table 62 slidably installed on the pair of guide rails 61. A cutting means 14 for cutting the wafer W is provided below the Z-axis table 62.

  Nut portions are formed on the back sides of the Y-axis table 52 and the Z-axis table 62, and ball screws 53 and 63 are screwed into these nut portions. A drive motor 64 (a Y-axis drive motor is not shown) is coupled to one end of a ball screw 53 for the Y-axis table 52 and a ball screw 63 for the Z-axis table 62. Each ball screw 53, 63 is rotationally driven by the drive motor 64, so that the cutting means 14 is indexed in the Y direction orthogonal to the X direction along the guide rail 51, and the cutting means 14 is along the guide rail 61. Then, the wafer is cut and fed in the Z direction approaching and leaving the wafer W.

  The cutting means 14 is configured by attaching a cutting blade 71 to the tip of a spindle 72 (see FIG. 2) protruding from the housing 75. The housing 75 is rotatably supported by a spindle 72 serving as a rotating shaft of the cutting blade 71 and is provided with a motor (not shown) that rotates the spindle 72. A blade cover 73 surrounding the cutting blade 71 is provided on the front end side of the housing 75 so as to expose a region where the cutting blade 71 cuts into the wafer W. The blade cover 73 is provided with a cutting water nozzle 74 (not shown in FIG. 1, refer to FIG. 2) for injecting cutting water toward the cutting portion of the wafer W.

  The housing 75 of the cutting means 14 is provided with an image pickup means 17 for picking up an upper surface of the wafer W, and the cutting blade 71 is aligned with the wafer W based on the image picked up by the image pickup means 17. By this alignment, the direction of the division line of the wafer W on the chuck table 12 is aligned with the cutting direction of the cutting blade 71. The cutting blade 71 is formed in a disk shape in which diamond abrasive grains are hardened with a resin bond, for example. The cutting means 14 divides the wafer W into individual devices by cutting the wafer W along the planned dividing line by the cutting blade 71 while the cutting water is jetted.

  By the way, in the cutting apparatus 1, the outer periphery of the wafer W is estimated using setting information such as the outer diameter size of the wafer W, and the cutting blade 71 is cut and fed downward outside the outer periphery of the wafer. However, when the outer diameter size of the wafer W is erroneously set, the wafer W may be cut from directly above by the cutting blade 71. Since the cutting load with respect to the cutting blade 71 is large at this time, the cutting blade 71 is consumed violently. The reason why the cutting load when cutting from right above is large is that the area where the cutting blade 71 hits the wafer W is larger than when the cutting blade 71 is applied from the side to the wafer W as in the case of traverse cutting. .

  With the worn cutting blade 71, even if the wafer W is cut with the full cut setting, insufficient cutting occurs and the wafer W is half cut. Although it is conceivable to detect the outer periphery of the wafer W in order to avoid cutting from above the wafer W, it takes time to search the outer periphery of the wafer W by the imaging means 17. Therefore, in the present embodiment, the abnormal vibration detection means 90 (see FIG. 2) detects abnormal vibration that occurs at the time of cutting feed, thereby detecting wear of the cutting blade 71. This prevents insufficient cutting of the wafer W by the cutting blade 71.

  Hereinafter, the abnormal vibration detecting means will be described in detail with reference to FIG. FIG. 2 is a schematic diagram of the abnormal vibration detecting means according to the present embodiment. In FIG. 2, the cutting means and the wafer are indicated by a two-dot chain line for convenience of explanation.

  The abnormal vibration detecting means 90 detects the vibration of the rotating cutting blade 71 by the vibration detecting unit 91, and determines the abnormal vibration by the determining unit 92 based on the detection result of the vibration detecting unit 91. The vibration detection unit 91 is an optical sensor including a light projecting unit 93 and a light receiving unit 95, and the measurement light projected from the light projecting unit 93 is received by the light receiving unit 95. The light projecting portion 93 is attached to the blade cover 73, and the light receiving portion 95 is attached to the standing wall portion 81 (see FIG. 1). The light projecting surface 94 of the light projecting portion 93 and the light receiving surface 96 of the light receiving portion 95 are Y It arrange | positions so that it may oppose in a direction. For this reason, vibration during cutting of the cutting blade 71 is transmitted to the light projecting unit 93 through the blade cover 73, and the optical axis of the measurement light from the light projecting unit 93 is blurred.

  Further, when the cutting edge of the cutting blade 71 is lowered to the target position H at the time of full cutting, the light receiving unit 95 is located at a position where the centers of the light receiving surface 96 of the light receiving unit 95 and the light projecting surface 94 of the light projecting unit 93 coincide. Is provided. That is, when the wafer W is completely cut by the cutting blade 71, the light receiving unit 95 is at a height at which the distance from the target position H to the light projecting unit 93 and the distance from the target position H to the light receiving unit 95 coincide. is set up. For this reason, when the cutting blade 71 cuts the wafer W from right above and the cutting blade 71 vibrates abnormally, the center of the light projecting surface 94 of the light projecting unit 93 deviates from the center of the light receiving surface 96 of the light receiving unit 95 and the amount of received light. Fluctuates.

  The determination unit 92 determines that the vibration is abnormal when the vibration detected by the vibration detection unit 91 exceeds a preset allowable value when the cutting blade 71 is cut into the wafer W by the cutting feed unit 16. More specifically, the determination unit 92 determines that there is abnormal vibration when the amount of light received by the light receiving unit 95 falls below an allowable value of light reception that is set in advance as a criterion for determining abnormal vibration. If the determination unit 92 determines that the vibration is abnormal, the cutting by the cutting device 1 is stopped and the operator is notified of the abnormal vibration. Further, dressing or re-setup for the cutting blade 71 may be performed after the cutting device 1 is stopped.

  The determination unit 92 includes a processor that executes various processes, a memory, and the like. The memory is composed of one or a plurality of storage media such as a ROM (Read Only Memory) and a RAM (Random Access Memory) depending on the application. The memory may store an abnormal vibration determination processing program, a cutting blade 71 dressing program, and a re-setup program. The determination unit 92 may be provided in a control unit (not shown) or may be provided in the light receiving unit 95. In addition, although the vibration detection part 91 is not restricted to an optical sensor, it is possible to comprise the vibration detection part 91 at low cost by using an optical sensor.

  Next, the abnormality detection operation of the cutting blade will be described with reference to FIGS. FIG. 3 is an operation transition diagram of the cutting operation according to the present embodiment. FIG. 4 is an explanatory diagram showing the relationship between the amount of received light and time according to the present embodiment. In FIG. 4, the horizontal axis indicates time, and the vertical axis indicates the amount of received light.

  As shown in FIG. 3A, in the initial state at the start of the cutting feed, the cutting blade 71 is not lowered, and the cutting blade 71 is largely separated from the target position H of the cutting feed. At this time, the light projecting unit 93 is located above the light receiving unit 95, and the light projecting surface 94 of the light projecting unit 93 and the light receiving surface 96 of the light receiving unit 95 do not face each other. That is, as shown in FIG. 4A, the centers of the light projecting surface 94 and the light receiving surface 96 are greatly deviated in the Z direction, and the light projecting surface 94 and the light receiving surface 96 do not overlap at all in the Y direction. Therefore, the measurement light from the light projecting surface 94 is not received by the light receiving surface 96, and in the graph showing the change in the amount of received light, the amount of received light changes without changing from the zero state.

  As shown in FIG. 3B, when the cutting blade 71 is further cut and fed in the Z direction, the cutting blade 71 is brought close to the target position H for the cutting feed. At this time, the light projecting unit 93 is brought closer to the light receiving unit 95, and the light projecting surface 94 of the light projecting unit 93 and the light receiving surface 96 of the light receiving unit 95 begin to face each other. That is, as shown in FIG. 4B, the centers of the light projecting surface 94 and the light receiving surface 96 are brought closer to each other in the Z direction, and the light projecting surface 94 and the light receiving surface 96 begin to partially overlap in the Y direction. Therefore, the measurement light from the light projecting surface 94 starts to be received by the light receiving surface 96, and the graph showing the change in the amount of received light changes so that the amount of received light gradually increases with time.

  As shown in FIG. 3C, when the wafer W is cut by the cutting blade 71, the cutting blade 71 is lowered to the cutting feed target position H while being vibrated by the cutting load. At this time, the vibration of the cutting blade 71 is transmitted to the light projecting unit 93 via the blade cover 73, and the light projecting surface 94 of the light projecting unit 93 and the light receiving surface 96 of the light receiving unit 95 face each other in the vibrated state. That is, as shown in FIG. 4C, the light projecting surface 94 vibrates in the Z direction around the position where the centers of the light projecting surface 94 and the light receiving surface 96 coincide with each other in the Z direction. Therefore, a part of the measurement light from the light projecting surface 94 is not received by the light receiving surface 96, and in the graph showing the change in the amount of received light, the amount of received light changes while repeating increase and decrease over time.

  In this case, the detection result is output from the light receiving unit 95 to the determination unit 92 (see FIG. 2). After the cutting blade 71 is lowered to the target position H, the determination unit 92 determines that the vibration is abnormal when the amount of received light exceeds the allowable value in the decreasing direction. More specifically, when the amount of received light exceeds the allowable value in the increasing direction, and thereafter the amount of received light falls below the allowable value, the determination unit 92 determines abnormal vibration. Thereby, it is grasped that the wafer W was cut from right above by the cutting blade 71 when the cutting blade 71 was cut and fed in the Z direction on the cutting device 1 side. When abnormal vibration is detected, cutting is stopped and the operator is notified.

  Therefore, the wafer is not cut in a state where the cutting blade 71 is consumed due to the cutting from above with respect to the wafer W, and the wafer W is not insufficiently cut. After the cutting means 14 is stopped, the cutting blade 71 may be dressed or re-setup. The determination unit 92 may determine that the vibration is abnormal immediately after the amount of received light exceeds the allowable value in the decreasing direction, or may determine that the vibration is abnormal after a predetermined time has elapsed after the amount of received light exceeds the allowable value in the decreasing direction. May be.

  Note that a prescribed allowable value may be set in the cutting device, or an allowable value may be set based on a change in the amount of received light when not cutting. Hereinafter, the setting operation of the allowable value will be described with reference to FIG. FIG. 5 is an explanatory diagram of an allowable value setting operation according to the present embodiment.

  As shown in FIG. 5A, the cutting blade 71 is cut and fed in a state where the wafer W is not held by the chuck table 12. Then, the cutting blade 71 is lowered to the cut feed target position H where the centers of the light projecting surface 94 of the light projecting unit 93 and the light receiving surface 96 of the light receiving unit 95 coincide. At this time, as shown in FIG. 5B, the light projecting surface 94 of the light projecting unit 93 and the light receiving surface 96 of the light receiving unit 95 start to partially overlap in the Y direction, and the measurement light from the light projecting surface 94 is received by the light receiving surface 96. The amount of received light gradually increases as time passes. When the centers of the light projecting surface 94 and the light receiving surface 96 coincide with each other, the amount of received light is maximized, and thereafter, the light receiving surface 96 is leveled while finely vibrating.

  The allowable value of the received light amount is set based on the maximum value of the received light amount in the light receiving unit 95. For example, the allowable value is set to a value lower by a predetermined amount than the maximum value of the received light amount. More specifically, the allowable value is a value that is lower than the maximum value of the amount of received light and is capable of detecting abnormal vibration, that is, a value that is lower than the upper limit value during abnormal vibration and higher than the lower limit value as shown by a two-dot chain line. Set to Thereby, it is possible to set an appropriate allowable value.

  As described above, according to the cutting device 1 according to the present embodiment, the cutting blade 71 is cut and fed in the Z direction, and abnormal vibration is detected when the vibration of the cutting blade 71 exceeds the allowable value. Since abnormal vibration occurs when the wafer W is cut directly from directly above, the cutting apparatus 1 can recognize the severe wear of the cutting blade 71. For this reason, cutting is stopped when the abnormal vibration is detected, so that cutting of the wafer W is not started in a state where the cutting blade 71 is consumed, and insufficient cutting of the wafer W can be prevented.

  By the way, in the present embodiment, when the cutting blade 71 is lowered to the target position H of the cutting feed, the light receiving unit 96 and the center of the light projecting surface 94 of the light projecting unit 93 coincide with each other. Although 95 was installed, it is not limited to this configuration. When the cutting blade 71 is lowered to the target position H for the cut feed, the centers of the light receiving surface 96 of the light receiving unit 95 and the light projecting surface 94 of the light projecting unit 93 do not have to coincide with each other. Hereinafter, the positional relationship between the light projecting unit and the light receiving unit according to the modification will be described with reference to FIG. In addition, in a modification, the same code | symbol is attached | subjected and demonstrated about the same name as this Embodiment.

  As shown in FIG. 6, the light receiving unit 95 overlaps the light receiving surface 96 of the light receiving unit 95 and the light projecting surface 94 of the light projecting unit 93 when the cutting edge of the cutting blade 71 is lowered to the target position H at the time of full cut. It is provided at a position where is minimized. That is, when the wafer W is completely cut with the cutting blade 71, the light receiving unit is set at a height that allows the measurement light from the light projecting unit 93 to be received by the light receiving unit 95 at a position lower than the light projecting unit 93. 95 is installed. For this reason, when the cutting blade 71 cuts the wafer W from right above and the cutting blade 71 vibrates abnormally, the light receiving surface 96 of the light receiving unit 95 is completely detached from the light projecting surface 94 of the light projecting unit 93 and the amount of received light is zero. become.

  The determination unit 92 determines that the vibration is abnormal when the vibration detected by the vibration detection unit 91 exceeds a preset allowable value when the cutting blade 71 is cut into the wafer W by the cutting feed means 16. In the comparative example, the determination unit 92 determines that there is abnormal vibration when the amount of light received by the light receiving unit 95 becomes 0, which is a criterion for determining abnormal vibration. That is, in the vibration detection using the optical sensor, “exceeding the allowable value” indicates that the amount of received light is equal to or less than the allowable value, and includes that the amount of received light is zero. In the modified example, the setting operation of the allowable value is eliminated, so that the configuration can be simplified.

  Next, an abnormal vibration detection operation of the cutting blade according to the modification will be briefly described with reference to FIG. FIG. 7 is an explanatory diagram showing the relationship between the amount of received light and time according to a modification. In FIG. 7, the horizontal axis indicates time, and the vertical axis indicates the amount of received light.

  As shown in FIG. 7A, in the initial state at the start of the cutting feed, the centers of the light projecting surface 94 and the light receiving surface 96 are greatly deviated in the Z direction, and the light projecting surface 94 and the light receiving surface 96 do not overlap at all in the Y direction. The received light amount does not change from 0. As shown in FIG. 7B, when the cutting blade 71 is cut and fed so that the light projecting surface 94 and the light receiving surface 96 slightly overlap in the Y direction, the amount of received light slightly increases from the zero state. As shown in FIG. 7C, when the cutting blade 71 vibrates and the vibration is transmitted to the light projecting unit 93, the light projecting surface 94 is completely detached from the light receiving surface 96 and the amount of received light becomes zero. The determination unit 92 (see FIG. 6) determines that there is abnormal vibration when the amount of received light becomes zero and stops cutting. As described above, when the cutting blade 71 is cut and fed to the wafer W, the amount of light received by the light receiving unit 95 should gradually increase, but when the amount of received light becomes 0, the determination unit determines that the vibration is abnormal. 92.

  In addition, this invention is not limited to the said embodiment, It can change and implement variously. In the above-described embodiment, the size, shape, and the like illustrated in the accompanying drawings are not limited to this, and can be appropriately changed within a range in which the effect of the present invention is exhibited. In addition, various modifications can be made without departing from the scope of the object of the present invention.

  For example, in the above-described embodiment, the optical sensor including the light projecting unit 93 and the light receiving unit 95 is used as the vibration detection unit, but the configuration is not limited to this. The vibration detection unit 91 only needs to detect vibration of the rotating cutting blade 71. For example, an AE (Acoustic Emission) sensor that detects the degree of destruction when the wafer W is cut into the cutting blade 71. But you can. In this case, an AE sensor that can detect only vertical vibration is used. The AE sensor is disposed on the housing 75 that rotatably supports the spindle 72 or the blade cover 73 that surrounds the cutting blade 71, and can measure the vibration in the Z direction transmitted from the cutting blade 71 at the time of cutting. When the AE sensor is used, the horizontal axis of FIGS. 4, 5, and 7 is time, the vertical axis is the amplitude amount, and a predetermined amplitude amount is set as the allowable value.

  In the above-described embodiment, the configuration in which the light projecting unit 93 is provided in the blade cover 73 has been described, but the configuration is not limited to this configuration. The light projecting unit 93 only needs to be provided at a position where the vibration of the cutting blade 71 is transmitted. For example, the light projecting unit 93 may be provided in the housing 75.

  Further, in the above-described embodiment, the configuration in which the light projecting unit 93 is provided in the blade cover 73 and the light receiving unit 95 is provided in the standing wall portion 81 has been described, but the configuration is not limited thereto. The light receiving part 95 may be provided on the blade cover 73, and the light projecting part 93 may be provided on the standing wall part 81. In this case, as described above, the light receiving unit 95 is not limited to the blade cover 73 and may be provided at a position where vibration of the cutting blade 71 is transmitted.

  In the above-described embodiment, the configuration in which the cutting apparatus 1 cuts the wafer W with the single cutting means 14 has been described. However, the present invention is not limited to this configuration. The cutting apparatus 1 may cut the wafer W with a pair of cutting means 14. In this case, each part of the cutting device 1 is preferably formed so that light projection from the light projecting part 93 of one cutting means 14 and light reception by the light receiving part 95 are not hindered by the other cutting means 14. .

  Further, in the present embodiment described above, the chuck table 12 is cut and fed to the cutting means 14 by the cutting feed means 13 in the X direction, and the cutting means 14 is moved to the chuck table 12 by the index feeding means 15 in the Y direction. The cutting means 14 is cut and fed in the Z direction with respect to the chuck table by the cutting feed means 16, but is not limited to this structure. The cutting feed means 13, the index feed means 15, and the cutting feed means 16 may be configured to move the chuck table 12 and the cutting means 14 relatively in the X direction, the Y direction, and the Z direction. For example, the cutting means 14 is cut and fed in the X direction with respect to the chuck table by the cutting feed means 13, the chuck table 12 is indexed and fed in the Y direction with respect to the cutting means 14 by the index feeding means 15, and the cutting feed means 16 The chuck table 12 may be cut and fed in the Z direction with respect to the cutting means 14.

  In the above-described embodiment, the determination unit 92 determines that the vibration is abnormal when the amount of received light falls below the allowable value. However, the present invention is not limited to this configuration. If the determination unit 92 determines that abnormal vibration occurs when the vibration detected by the vibration detection unit 91 exceeds a preset allowable value when the cutting blade 71 is cut into the wafer W by the cutting feed means 16, how is it determined? It may be configured. The time when the cutting blade 71 is cut into the wafer W refers to the time until the cutting feed operation for cutting and feeding by the cutting feed means 16 is completed.

  In the above-described embodiment, the abnormal vibration is determined based on a single allowable value. However, the present invention is not limited to this configuration. For example, an upper limit and a lower limit of an allowable value may be set, and it may be determined as abnormal vibration when the amount of light received exceeds the upper limit and the lower limit of the allowable value. For example, the allowable range is the amplitude of the amount of light received when the cutting blade 71 is not cut into the wafer W. That is, the amplitude of the received light amount when the cutting blade 71 is not cut into the wafer W is not abnormal, and the allowable value is exceeded until the cutting operation of the cutting blade 71 by the cutting feed means 16 is completed. Sometimes it is judged as abnormal vibration.

  As described above, the present invention has an effect that the wafer can be satisfactorily cut without causing insufficient cutting by the cutting blade, and is particularly useful for a cutting apparatus that cuts the wafer with the cutting blade.

DESCRIPTION OF SYMBOLS 1 Cutting device 12 Chuck table 13 Cutting feed means 14 Cutting means 15 Index feed means 16 Cutting feed means 17 Imaging means 71 Cutting blade 72 Spindle 75 Housing 90 Abnormal vibration detection means 91 Vibration detection part 92 Judgment part 93 Light projection part 94 Light projection Surface 95 Light receiving part 96 Light receiving surface W Wafer H Target position

Claims (2)

A chuck table for holding the wafer;
A cutting means for cutting a wafer held by the chuck table with a rotatable cutting blade;
Cutting feed means for relatively cutting and feeding the chuck table and the cutting means in the X direction which is the cutting direction of the cutting blade;
Index feeding means for index feeding the chuck table and the cutting means in the Y direction relatively orthogonal to the X direction;
An infeed means for incising and feeding the cutting blade in the Z direction toward and away from the wafer;
An abnormal vibration detecting means for detecting abnormal vibration of the cutting means, and a cutting device comprising:
The abnormal vibration detecting means includes
A vibration detecting unit for detecting vibration of the cutting blade during rotation;
A cutting apparatus comprising: a determination unit that determines that the vibration detected by the vibration detection unit exceeds a preset allowable value when the cutting blade is cut into the wafer by the cutting feed unit. The vibration detector is
A light projecting unit that projects measurement light, and a light receiving unit that receives the measurement light projected from the light projecting unit when the cutting blade cuts into the wafer,
The cutting device according to claim 1, wherein the determination unit determines that the vibration is abnormal when the amount of light received by the light receiving unit exceeds a preset allowable value.

Images