JP6234250B2 - Dressing tools - Google Patents

Description

  The present invention relates to a dressing tool for dressing a grindstone.

  In recent years, in order to realize a small and light device, it is required to thinly grind a wafer made of a material such as silicon or sapphire. The grinding of the wafer is performed by, for example, a grinding apparatus equipped with a grinding wheel including a grinding wheel (grinding wheel) for grinding. The wafer can be ground by holding the wafer on the holding table of the grinding apparatus and pressing the grinding wheel of the rotating grinding wheel against the processing surface of the wafer.

  The above-described grinding wheel is formed, for example, by mixing abrasive grains such as diamond and CBN with a binder such as vitrified or resinoid. When the wafer is rubbed with this grinding wheel, a large number of abrasive grains exposed on the surface of the grinding wheel act as cutting edges, and the work surface of the wafer is scraped off.

  On the other hand, as the grinding progresses, the grinding wheel also wears, and new abrasive grains appear one after another on the surface of the grinding wheel that comes into contact with the work surface of the wafer. By this action (referred to as a self-generated blade action or the like), it is possible to suppress a decrease in grinding performance due to abrasive grain clogging, clogging, crushing, etc., and realize a good grinding process.

  By the way, an unused grinding wheel does not properly express abrasive grains, and the surface height of the grinding wheel also varies. Therefore, a dressing process for grinding the dressing board is performed before grinding the wafer in order to properly express the abrasive grains and to make the height of the surface of the grinding wheel uniform (see, for example, Patent Document 1).

  The dressing board used in the dressing process is formed to have a thickness of about 1 mm to 5 mm, for example, and the back side is bonded to a resin support plate. The dressing board is worn by friction with the grinding wheel and is replaced when it becomes thin to a certain extent. The timing for changing the dressing board is determined by a method such as visual inspection.

JP 2009-142906 A

  However, with the method such as visual observation described above, it is not always possible to appropriately determine the replacement timing of the dressing board. Therefore, there is a possibility that the support plate is accidentally ground by using the dressing board worn to the limit (use limit) without being replaced, and the grinding wheel is damaged.

  This invention is made | formed in view of this problem, The place made into the objective is to provide the dressing tool which can detect a use limit appropriately.

According to the present invention, there is provided a dressing tool for dressing a grinding wheel mounted on a grinding wheel, comprising: a dressing board for dressing the grinding wheel; and a support plate having the dressing board fixed to an upper surface thereof, On the surface side of the dressing board, there is a groove portion having a depth corresponding to the thickness of the use limit of the dressing board, and has a predetermined length in a direction parallel to the surface of the dressing board. The groove is formed deeper toward the end , and when the grinding wheel is dressed with the dressing board, the surface of the dressing board is worn and the groove becomes shallow and the groove cannot be identified. in conjunction with it detects that the thickness of the dressing board reaches the thickness of the use limit, the dressing Dressing tool is provided over de, characterized in that the said length of the groove portion is shortened as worn.

  Since the dressing tool of the present invention has a groove or a step having a depth corresponding to the thickness of the use limit of the dressing board on the surface side of the dressing board, when the dressing board is worn to the thickness of the use limit, the groove or step Cannot be identified. Therefore, the use limit of the dressing board can be appropriately detected based on whether or not the groove portion or the step portion can be identified.

1A is a perspective view schematically showing a dressing tool according to the present embodiment, FIG. 1B is a cross-sectional view schematically showing the dressing tool, and FIG. FIG. 2 is an enlarged cross-sectional view of a part of FIG. It is a perspective view which shows typically the use condition of a dressing tool. FIG. 3A is a cross-sectional view schematically showing a dressing tool according to a first modification, and FIG. 3B is a cross-sectional view schematically showing a dressing tool according to a second modification.

  Embodiments of the present invention will be described with reference to the accompanying drawings. 1A is a perspective view schematically showing a dressing tool according to the present embodiment, FIG. 1B is a cross-sectional view schematically showing the dressing tool, and FIG. FIG. 2 is an enlarged cross-sectional view of a part of FIG. Note that FIG. 1B shows a cross-section AA ′ of FIG. 1A, and FIG. 1C shows an enlarged region B of FIG. 1B.

  As shown in FIGS. 1A and 1B, the dressing tool 2 according to the present embodiment supports a substantially flat disk-shaped dressing board 4 and the dressing board 4 below the dressing board 4. And a support plate 6.

  The support plate 6 is formed in a disk shape having a larger diameter than the dressing board 4 with a material such as resin so that the entire dressing board 4 can be supported. The back surface (lower surface) 4 b side of the dressing board 4 is bonded to the upper surface 6 a of the support plate 6. On the surface (upper surface) 4 a side of the dressing board 4, a groove (groove portion) 4 c for identifying the use limit of the dressing board 4 is provided.

  The grinding wheel 9b can be dressed by pressing the grinding wheel 9b (see FIG. 2) against the upper surface 4a of the dressing board 4 while rotating the dressing tool 2 and the grinding wheel 9 (see FIG. 2).

  The dressing board 4 is formed using, for example, a mixed material in which abrasives such as white alundum (WA) and green carbon (GC) are mixed with a binder such as vitrified or resinoid. However, the binder and the abrasive grains constituting the dressing board 4 are changed according to the grinding wheel 9b to be dressed.

  The groove 4c of the dressing board 4 is formed, for example, by cutting a rotating cutting blade (not shown) into a flat dressing board. As shown in FIG. 1C, the groove 4 c has a depth D corresponding to the use limit thickness T of the dressing board 4. Specifically, the bottom 4d of the groove 4c is positioned at a depth D from the front surface 4a, and is positioned at a thickness T from the back surface 4b.

  Further, the groove 4 c is formed with an arbitrary length and width in an in-plane direction parallel to the surface 4 a of the dressing board 4. For example, in FIG. 1, a groove 4c having a length from the center of the dressing board 4 to the outer peripheral edge and a width of about 1 mm is formed. However, the groove 4c only needs to be formed so as to be identified by a method such as visual inspection or contact, and the length, width, shape, and the like of the groove 4c can be arbitrarily changed.

  Next, dressing of the grinding wheel 9b using the dressing tool 2 of the present embodiment will be described. FIG. 2 is a perspective view schematically showing a use state of the dressing tool 2 according to the present embodiment.

  As shown in FIG. 2, the grinding apparatus 1 includes a holding table 3 that sucks and holds a workpiece (not shown) such as a wafer. A rotation mechanism (not shown) such as a motor is provided below the holding table 3, and the holding table 3 rotates around a rotation axis extending in the vertical direction by the rotation mechanism.

  The surface (upper surface) of the holding table 3 is a holding surface for sucking and holding the workpiece. A negative pressure of a suction source (not shown) acts on the holding surface through a suction path (not shown) formed inside the holding table 3 to generate a suction force for sucking the workpiece.

  A grinding mechanism is disposed above the holding table 3. The grinding mechanism includes a spindle 5 that is connected to a rotation mechanism (not shown) such as a motor and supported by an elevating mechanism (not shown). The spindle 5 rotates around a rotating shaft extending in the vertical direction by the rotational force transmitted from the rotating mechanism and is moved up and down by the lifting mechanism.

  A disc-shaped wheel mount 7 is fixed to the lower end side of the spindle 5, and a grinding wheel 9 is attached to the wheel mount 7. The grinding wheel 9 includes a wheel base 9a made of a metal material such as aluminum or stainless steel. A plurality of grinding wheels 9b are fixed to the annular lower surface of the wheel base 9a over the entire circumference.

  When dressing the grinding wheel 9b, the grinding wheel 9 and the holding table 3 are rotated and the spindle 5 is lowered while the lower surface 6b side of the support plate 6 is sucked and held on the surface of the holding table 3. If the lowering amount of the spindle 5 is adjusted so as to press the lower surface of the grinding wheel 9b against the surface 4a of the dressing board 4, the grinding wheel 9b can be dressed.

  When the surface 4a side of the dressing board 4 is worn by the dressing described above and the dressing board 4 becomes thin, the groove 4c formed in the dressing board 4 also becomes shallow. As described above, the groove 4 c is formed with a depth D corresponding to the thickness T of the use limit of the dressing board 4. For this reason, when the dressing board 4 is thinned to a thickness T of the limit of use, the groove 4c is almost lost, and the groove 4c cannot be identified by a method such as visual inspection or contact.

  As described above, the dressing tool 2 of the present embodiment has the groove (groove portion) 4c having a depth D corresponding to the thickness T of the dressing board 4 on the surface 4a side of the dressing board 4, When the dressing board 4 is worn down to a thickness T that is the limit of use, the groove 4c cannot be identified. Therefore, the use limit of the dressing board 4 can be appropriately detected based on whether or not the groove 4c can be identified.

  In addition, this invention is not limited to description of the said embodiment, A various change can be implemented. For example, in the embodiment described above, the groove 4c having a substantially constant depth from the surface 4a is formed, but the groove 4c has a depth corresponding to the thickness T of the use limit of the dressing board 4 at least partially. It may be formed of D. That is, the groove 4c may not be formed with a substantially constant depth.

  FIG. 3A is a cross-sectional view schematically showing the dressing tool 2 according to the first modification. The dressing board 4 of the dressing tool 2 according to the first modification is formed with a groove 4c different from the above embodiment. Specifically, in the first modification, a groove 4c is formed so as to deepen from one end 4e to the other end 4f in a direction parallel to the surface 4a of the dressing board 4.

  When the dressing board 4 having such a groove 4c is worn, the length of the groove 4c is shortened in the direction parallel to the surface 4a. Therefore, the state of the dressing tool 2 can be confirmed based on the length of the groove 4c. For example, when the groove 4c has become sufficiently short, it can be determined that the use limit of the dressing board 4 is close. Therefore, by preparing a new dressing tool 2 for replacement, the operating rate of the grinding apparatus 1 can be increased. Decline can be prevented.

  Moreover, in the said embodiment and modification, although the groove | channel 4c is provided in order to detect the use limit of the dressing board 4, the structure for detecting the use limit of the dressing board 4 is not necessarily the groove | channel 4c. good.

  FIG. 3B is a cross-sectional view schematically showing the dressing tool 2 according to the second modification. On the dressing board 4 of the dressing tool 2 according to the second modification, a step (step portion) 4g is formed instead of the groove 4c of the above embodiment. The step 4g is formed at a depth D corresponding to the thickness T of the use limit of the dressing board 4 at the outer peripheral edge on the surface 4a side.

  The step 4g is formed by, for example, grinding the outer peripheral edge of a flat dressing board with the grinding device 1 or cutting with a cutting blade (not shown). The depth of the step 4g does not have to be substantially constant. Specifically, at least a part of the step 4g has only to be formed with a depth D corresponding to the use limit thickness T of the dressing board 4.

  The dressing tool 2 described above may be used for the purpose of shaping the grinding wheel 9b, or may be used for the purpose of sharpening the grinding wheel 9b. For the purpose of shaping the grinding wheel 9b, the dressing board 4 containing relatively large size abrasive grains is used, and for the purpose of sharpening the grinding wheel 9b, the dressing board 4 containing relatively small size abrasive grains should be used. Is preferred.

  In addition, the configurations, methods, and the like according to the above-described embodiments can be changed as appropriate without departing from the scope of the object of the present invention.

2 Dressing tool 4 Dressing board 4a Surface (upper surface)
4b Back side (lower side)
4c Groove (groove)
4d bottom 4e one end 4f other end 4g step (step)
6 Support plate 6a Upper surface 6b Lower surface 1 Grinding device 3 Holding table 5 Spindle 7 Wheel mount 9 Grinding wheel 9a Wheel base 9b Grinding wheel D Depth T Thickness

Claims (1)

A dressing tool for dressing a grinding wheel mounted on a grinding wheel,
A dressing board for dressing the grinding wheel, and a support plate on which the dressing board is fixed to the upper surface,
On the surface side of the dressing board, there is a groove having a depth corresponding to the thickness of the use limit of the dressing board, and has a predetermined length in a direction parallel to the surface of the dressing board. The groove that deepens toward the other end is formed,
When the grinding wheel is dressed by the dressing board, the groove portion becomes shallow due to wear of the surface side of the dressing board, and the groove portion cannot be identified. A dressing tool characterized in that the length of the groove portion is shortened as the dressing board is worn while being able to detect reaching.

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