JP2019018268A - Working method - Google Patents

Abstract

To improve workability of working which dresses a cutting blade while performing cutting.SOLUTION: A working method for cutting a plate-like object (10) on which a plurality of division schedule lines (11) are formed with a cutting blade (33) includes: a dress layer formation step of uniformly applying liquid resins (P1 and P2) containing abrasive grains for dressing that dresses the cutting blade onto a surface of a plate-like object to cure the resins, and forming dress layers (15 and 16); a cutting step of performing a cutting work along the division schedule lines with the cutting blade while supplying cutting water (W); and a dress layer removal step of removing a dress layer. The dress layer formed by curing a liquid resin has high setting flexibility of a thickness and can improve workability by setting its thickness to appropriate thickness corresponding to an edge takeout quantity of the cutting blade.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a method for processing a plate-like object.

  When a plate-like workpiece such as a wafer is cut by a cutting blade, the cutting portion of the cutting blade is clogged or crushed, resulting in poor sharpness. Therefore, a dressing dress that restores the sharpness by cutting the cutting blade into a dress member such as a dresser board is performed at a predetermined timing. However, when dressing dressing is performed as a separate process from the cutting process, it takes time and labor. Also, if the material of the workpiece is glass, etc., which is harder than silicon wafers, the cutting blade will become clogged more frequently and sufficient sharpness may not be obtained simply by dressing after cutting. It was. As a technique for solving these problems, there has been proposed a machining method in which a workpiece is machined while dressing to eliminate clogging by cutting the workpiece together with a dressing member for dressing (see, for example, Patent Document 1). .

Japanese Patent Laying-Open No. 2015-213969

  However, if a board or tape (sheet) dress member is formed on the surface of the workpiece, the thickness of the object to be cut by the cutting blade increases. Therefore, the cutting edge of the cutting blade (depth at which the cutting blade can be cut) There is a possibility that the processing cannot be performed when the is small. For example, if the cutting blade has insufficient rigidity, it may cause a vibration in the direction of the rotation axis during high-speed rotation, resulting in cutting failure. Therefore, the width (thickness in the direction of the rotation axis) and the cutting edge amount to ensure the required rigidity A correlation is defined, and the cutting edge amount decreases as the width of the cutting blade decreases. Therefore, there is a problem that the existing dressing member cannot be processed together with the workpiece with a thin cutting blade that tends to have a small blade tip protruding amount.

  The present invention has been made in view of such problems, and provides a machining method that is capable of sharpening the cutting blade while performing cutting and having excellent workability even when the cutting edge amount of the cutting blade is limited. For the purpose.

  The present invention relates to a machining method for machining a plate-like object having a plurality of division lines formed on the surface along the division line using a cutting blade, wherein the cutting blade is sharpened on the surface of the plate-like object. After applying the dressing layer forming step to form a dressing layer by uniformly applying and curing a liquid resin containing sharpening abrasive grains for performing the dressing layer forming step, the cutting line is supplied while cutting water is supplied. A cutting step that performs cutting with a cutting blade along the cutting step, and a dress layer removal step that removes the dress layer after performing the cutting step.

  According to the above processing method, since the dressing layer is formed by applying the liquid resin containing the abrasive for dressing dressing, the conditions such as the coating amount are changed flexibly, and the amount of the tip of the cutting blade is extended to the dressing layer. Can be formed to an appropriate thickness according to the thickness. For this reason, even when a thin cutting blade with a small blade tip amount is used, it is possible to perform processing while appropriately dressing.

  In the dress layer forming step, the dress layer may be formed only on the planned division line. Thereby, the usage-amount of liquid resin can be reduced. Further, when an alignment target or the like is formed on the surface of the plate-like object, it can be reliably identified without being blocked by the dress layer.

  In the dress layer forming step, the dress layer is formed along the planned division line within a range equal to or narrower than the width of the cutting blade. In the cutting step, the cutting layer is cut along the planned division line and the dress layer is formed. May also be removed. Thereby, it takes less time to remove the dress layer, and the processing efficiency can be improved.

  As described above, according to the processing method of the present invention, even when the cutting edge amount of the cutting blade is limited, the cutting blade can be sharpened while cutting, and the workability of cutting can be improved. .

It is a figure which shows the dress layer formation step in the processing method of a 1st form. It is a figure which shows the cutting process step in the processing method of a 1st form. It is a figure which shows the dress layer formation step in the processing method of a 2nd form. It is a figure which shows the cutting process step in the processing method of a 2nd form.

  Hereinafter, the present embodiment will be described with reference to the accompanying drawings. 1 and 2 show a processing method of the first embodiment, and FIGS. 3 and 4 show a processing method of the second embodiment.

  The processing method of the first embodiment will be described with reference to FIGS. The workpiece 10 to be processed is a substantially disc-like plate-like object, and a grid-like division planned line 11 is formed on the surface. A device (not shown) is formed in each region partitioned by the planned division line 11. Although illustration is omitted, an alignment target is formed on the surface of the work 10 in a portion other than the device formation region defined by the division lines 11. The alignment target serves as an index for positioning the workpiece 10 in a cutting step described later.

  Although the material of the workpiece | work 10 is not limited, It is especially suitable as an application object of this invention that it is a difficult-to-cut material like a glass wafer. The hard-to-cut material is a material having a hardness higher than that of a silicon wafer or the like, and the cutting blade is likely to be clogged during cutting. However, the workpiece 10 may be a workpiece other than a glass wafer, and the type of device formed on the workpiece is not limited. For example, various workpieces such as a semiconductor device wafer, an optical device wafer, a package substrate, a semiconductor substrate, an inorganic material substrate, an oxide wafer, a raw ceramic substrate, and a piezoelectric substrate may be used. As the semiconductor device wafer, a silicon wafer or a compound semiconductor wafer after device formation may be used. As the optical device wafer, a sapphire wafer or silicon carbide wafer after device formation may be used. Further, a CSP (Chip Size Package) substrate may be used as the package substrate, silicon or gallium arsenide may be used as the semiconductor substrate, and sapphire, ceramics, glass, or the like may be used as the inorganic material substrate. Furthermore, as the oxide wafer, lithium tantalate or lithium niobate after device formation or before device formation may be used.

  First, a dress layer forming step is performed. FIG. 1 shows a case where an apparatus for spin coating is used to apply a liquid resin to the workpiece 10 in the dress layer forming step. The apparatus has a spinner table 20. A holding surface is formed of a porous ceramic material on the upper surface of the spinner table 20, and the work 10 can be sucked and held by driving a suction source (not shown) to apply a negative pressure to the holding surface. The workpiece 10 is held on the holding surface of the spinner table 20 with the surface on which the division lines 11 are formed facing upward. A rotating shaft 21 that is rotationally driven by a motor (not shown) is connected to the lower center portion of the spinner table 20. When the motor is driven, the spinner table 20 rotates about the axis in the Z-axis direction (vertical direction). The workpiece 10 held on the spinner table 20 rotates together with the spinner table 20.

  As shown in FIG. 1, a supply nozzle 22 is provided above the spinner table 20, and the liquid resin P <b> 1 is supplied from the liquid resin supply source 23 to the supply nozzle 22. The supply nozzle 22 drops the liquid resin P1 onto the center of the surface of the workpiece 10 on the rotating spinner table 20. The dropped liquid resin P1 is subjected to centrifugal force by the high-speed rotation of the work 10 on the spinner table 20 and spreads over the entire surface from the center to the outer edge of the work 10, and is a film-like layer (coating film) having a uniform thickness. ).

  In the dress layer forming step, the liquid resin may be applied to the workpiece 10 by spray coating instead of the spin coating shown in FIG. Although not shown, the apparatus for spray coating has a holding table for holding the workpiece 10 and a spray nozzle capable of spraying the liquid resin in a mist form. The holding table and the spray nozzle are relatively movable in the horizontal direction, and the spray nozzle and the holding table are moved relatively while spraying the liquid resin from the spray nozzle to the surface of the work 10 held on the holding table. Thus, the liquid resin can be applied on the surface of the workpiece 10 with a uniform thickness.

  The liquid resin P1 is normally in a liquid state and has a property of being cured by performing a predetermined curing process. For example, as the material of the liquid resin P1, an ultraviolet curable resin that is effective by ultraviolet irradiation, a thermosetting resin that is cured by applying heat, or the like can be used. The liquid resin P1 contains sharpening abrasive grains. The sharpening abrasive grains contained in the liquid resin P1 are alumina-based abrasive grains (for example, white alundum), silicon carbide-based abrasive grains (for example, green carbon), and the like. The abrasive content is selected.

  When the liquid resin P1 is applied to the entire surface of the workpiece 10 with a predetermined thickness, the liquid resin P1 is cured. As described above, the liquid resin P1 has a property of being cured by ultraviolet irradiation or heat treatment, and is cured using an ultraviolet irradiation device or a heating device according to the properties of the liquid resin P1. The liquid resin P1 may be cured under conditions other than ultraviolet rays and heat.

  When the curing of the liquid resin P1 is completed, the dress layer 15 containing the sharpening abrasive grains is formed on the entire surface of the workpiece 10 (see FIG. 2). The cured dress layer 15 is in close contact with the surface of the workpiece 10 and does not peel off unintentionally. The thickness of the dress layer 15 is set so that it can be cut together with the workpiece 10 in the next cutting step. In other words, the thickness of the dress layer 15 is selected according to the amount of leading edge of the cutting blade described later. When the dress layer forming step is performed by the above-described spin coating (FIG. 1), the thickness of the dress layer 15 can be set according to the dropping amount of the liquid resin P1 from the supply nozzle 22 and the like. When the dress layer forming step is performed by the spray coating described above, the thickness of the dress layer 15 can be set according to the amount of liquid resin sprayed from a spray nozzle (not shown). The dress layer 15 covers the entire surface of the workpiece 10, but the dress layer 15 has a predetermined transparency (light transmittance), and the alignment target formed on the workpiece 10 is optically transmitted through the dress layer 15. Can be identified.

  When the formation of the dress layer 15 is completed as described above, the cutting step shown in FIG. 2 is performed. In the cutting step, the workpiece 10 is conveyed to the cutting device while being supported by the ring frame 14 via the dicing tape 13. More specifically, the back surface of the workpiece 10 is attached to the center portion of the dicing tape 13, the annular ring frame 14 is attached to the outer peripheral portion of the dicing tape 13, and the workpiece 10 is positioned inside the opening of the ring frame 14. It is conveyed in the state to do. The dress layer forming step (FIG. 1) described above may be performed with the workpiece 10 supported via the dicing tape 13 and the ring frame 14.

  In the cutting apparatus, the workpiece 10 is sucked and held on the chuck table 30 via the dicing tape 13, and the ring frame 14 around the workpiece 10 is held on the annular table 31 by the clamp portion 32. The held workpiece 10 is cut along the scheduled division line 11 by a cutting blade 33 provided in the cutting device.

  The cutting device has a spindle (not shown) that can rotate around an axis that faces in the Y-axis direction (see FIG. 2), and a cutting blade 33 is attached to the tip of the spindle. The cutting blade 33 includes a hub blade having a cutting edge formed on an outer peripheral portion of a base fixed to the spindle, and a hubless blade (washer blade) which is composed of only an annular cutting blade and is fixed to the spindle via a mounter. Either of these is acceptable. The cutting blade 33 to be mounted on the spindle is selected such that the protruding amount of the cutting edge with respect to the hub or mounter in the outer diameter direction, that is, the blade tip protruding amount is larger than the thickness of the workpiece 10 to be cut.

  The dress layer 15 formed on the surface of the workpiece 10 in the dress layer forming step performed earlier is set to a thickness that can be cut by the cutting blade 33 together with the workpiece 10. In other words, the dress layer 15 is formed so that the total value of the thickness of the workpiece 10 and the thickness of the dress layer 15 is smaller than the cutting edge amount of the cutting blade 33.

  By rotating the spindle at a predetermined rotation speed, the cutting blade 33 rotates around the axis in the Y-axis direction. The cutting blade 33 is supported so as to be movable in the Z-axis direction shown in FIG. 2 with respect to the chuck table 30. By moving the cutting blade 33 downward in the Z-axis direction, the cutting depth with respect to the workpiece 10 is increased. . Further, the cutting blade 33 and the chuck table 30 can be moved relative to each other in the machining feed direction (direction perpendicular to the paper surface of FIG. 2) perpendicular to the Y-axis direction, and divided by the relative movement in the machining feed direction. The cutting blade 33 can be moved along the planned line 11.

  The cutting apparatus has an imaging unit (not shown) that images an alignment target (not shown) provided on the surface of the workpiece 10, and positions the cutting blade 33 with respect to the planned division line 11 with the imaged alignment target as a reference. The workpiece 10 is cut while cutting the dress layer 15 formed on the surface of the workpiece 10 (see FIG. 2). Since the dress layer 15 has transparency, the alignment target can be imaged through the dress layer 15 covering the entire surface of the workpiece 10.

  Of the three enlarged portions L1, L2, and L3 shown in FIG. 2, the right enlarged portion L1 is in a state before cutting by the cutting blade 33, and the central enlarged portion L2 is in the middle of cutting by the cutting blade 33. The left enlarged portion L3 shows a state in which cutting with the cutting blade 33 is completed and a cutting groove M is formed along the scheduled dividing line 11. At the time of cutting shown in the enlarged portion L2, the cutting blade 33 cuts the dress layer 15 together with the workpiece 10, and the cutting blade 33 is clogged by the action of the sharpening abrasive contained in the dress layer 15 so that cutting is performed while maintaining sharpness. Can proceed. In particular, the effect is high when the workpiece 10 is a glass wafer or the like that easily causes clogging of the cutting blade 33.

  When cutting with the cutting blade 33, cutting water W is jetted from the cutting water nozzle 34. The machining heat is cooled by the cutting water W, and the cutting waste generated with the cutting is washed away. Alternatively, the dress layer 15 may be formed of a hydrophilic resin, and the dress layer 15 may be softened by contact with the cutting water W so that the dress layer 15 can be easily removed from the workpiece 10 in the next dress layer removal step.

  When the cutting by the cutting blade 33 along one division line 11 is completed, the cutting blade 33 and the chuck table 30 are relatively moved in the Y-axis direction, and the cutting blade 33 is aligned with the next division line 11 to perform cutting. I do. In this way, when cutting is performed on all the scheduled division lines 11 with the cutting blade 33 and the cutting step is completed, the dress layer removing step is performed. As shown in the enlarged portion L3 in FIG. 2, in the completion stage of the cutting step, the dress layer 15 is removed together with the workpiece 10 in the region along the cutting groove M, while in the region other than the cutting groove M, the workpiece 10 is removed. The dress layer 15 remains on the surface. In the dress layer removal step, the remaining dress layer 15 is removed from the workpiece 10.

  In the dress layer removing step, the dress layer 15 is peeled from the workpiece 10 by a predetermined peeling means. The peeling means may be a jig that physically holds the dress layer 15 and pulls it in the peeling direction, or the dress layer 15 is subjected to a predetermined treatment to weaken or decompose the adhesiveness. Thus, a means for promoting peeling may be used. For example, it is possible to remove the dress layer 15 by forming the dress layer 15 from a water-expandable ultraviolet curable resin that is cured by ultraviolet rays and supplying water to cause the dress layer 15 to expand. Alternatively, the dress layer 15 can be formed by forming the dress layer 15 from a water-soluble thermoplastic resin that is liquefied at a predetermined temperature or more, and contacting the dress layer 15 with warm water at or above the temperature. By using the means for changing the form of the dress layer 15 from the cured state in this way, the dress layer 15 can be easily and reliably formed without causing damage to the work 10 due to residual adhesive force or contamination of the work 10 due to adhesive residue. Can be removed.

  Further, as described above, when the dress layer 15 is made of a hydrophilic resin, the dress layer 15 has already been softened by contact with the cutting water W (see FIG. 2) supplied in the previous cutting step. Therefore, the removal workability in the dress layer removal step is further improved.

  According to the above processing method, the dressing layer 15 is formed on the surface of the workpiece 10, and the dressing layer 15 is cut together with the workpiece 10, so that the cutting blade 33 can be sharpened while the workpiece 10 is being cut. Yes, the sharpness of the cutting blade 33 can be maintained during cutting. Since the dressing layer 15 is formed by applying the liquid resin P1 to the surface of the workpiece 10 and then curing, the thickness of the dressing layer 15 can be set flexibly (the degree of freedom in setting the thickness is high). The dress layer 15 having an optimum thickness corresponding to the amount of leading edge of the cutting blade 33 can be obtained. For example, the dress layer 15 formed by curing the liquid resin P1 has a uniform thickness as compared with a case where a plate-like dress member such as a dresser board or a tape (sheet) dress member is provided on the surface of the workpiece 10. It is possible to form a very thin film. Therefore, even if the cutting blade 33 used in the cutting apparatus is thin and has a small blade tip protrusion amount, the dress layer 15 having a thin thickness corresponding to the small blade tip protrusion amount is provided on the workpiece 10 so as to be processed. Can do.

  In addition, since the dress layer 15 is formed on the entire surface (surface) of the workpiece 10 on which the cutting blade 33 is cut (see FIG. 2), the cutting waste generated in the cutting step is less likely to adhere to the surface of the workpiece 10. Become. That is, the dress layer 15 also functions as a protective film when cutting the workpiece 10.

  Subsequently, a processing method of the second embodiment will be described with reference to FIGS. 3 and 4. In FIGS. 3 and 4, the portions denoted by the same reference numerals as those in FIGS. 1 and 2 are the same as those in the first embodiment described above, and redundant description is omitted.

  In the processing method of the second embodiment, as shown in FIG. 3, in the dress layer forming step, the liquid resin P2 containing the dressing dressing abrasive grains is applied only on the division planned line 11 in the surface of the work 10. More specifically, as shown in the enlarged portion L4 in FIG. 3, a supply nozzle 24 having a narrow opening at the lower end corresponding to the width of the division line 11 is provided. Then, the liquid resin P2 supplied from the liquid resin supply source 25 is dropped from the supply nozzle 24 in a state where the supply nozzle 24 is positioned on the planned division line 11. While dropping the liquid resin P2, the workpiece 10 and the supply nozzle 24 are moved relative to each other in the extending direction of the division line 11 (direction perpendicular to the paper surface of FIG. 3). Then, liquid resin P2 is apply | coated in the linear range which follows the division | segmentation planned line 11, like the enlarged part L5 of FIG. The thickness of the liquid resin P2 along each division line 11 is set to be equal.

  As a means for applying the liquid resin P2, as shown in FIG. 3, instead of applying the liquid resin P2 along the individual division lines 11 using the supply nozzle 24, a grid shape corresponding to the division lines 11 is used. It is also possible to use a mask (not shown) having an opening. A mask is placed on the surface of the workpiece 10 so that the lattice-shaped openings overlap the division planned lines 11, and the liquid resin P2 is applied from above the mask. Then, the liquid resin P2 is not applied to the area of the workpiece 10 covered with the mask, and the liquid resin P2 is applied only to the lattice-shaped opening (that is, the portion corresponding to the planned division line 11) that is not covered with the mask. The When such a mask is used, the liquid resin P2 can be applied quickly and easily.

  When the application of the liquid resin P2 on each division planned line 11 is completed, the liquid resin P2 is cured. The liquid resin P2 is cured by any means such as ultraviolet irradiation or heating, as in the first embodiment. When the liquid resin P <b> 2 is cured, the dress layer 16 (see FIG. 4) formed in a lattice-like region along the planned dividing line 11 is obtained. As shown in the enlarged portion L6 in FIG. 4, the dress layer 16 does not exist and the surface of the workpiece 10 is exposed in a region other than on the planned division line 11.

  When the formation of the dress layer 16 is completed, the cutting step shown in FIG. 4 is performed. In the cutting step, as in the first embodiment, the workpiece 10 is cut while cutting the dress layer 16 on the planned dividing line 11. As shown in the enlarged portion L7 in FIG. 4, the cutting blade 33 cuts the dress layer 16 together with the workpiece 10, and the clogging of the cutting blade 33 is reduced by the action of the sharpening abrasive grains contained in the dress layer 16, thereby improving the sharpness. Cutting can be performed while keeping.

  In the second embodiment, the dress layer 16 is formed only on the planned division line 11 on the surface of the workpiece 10, and the region other than the planned division line 11 is not covered with the dress layer 16. Therefore, the alignment target formed on the surface of the workpiece 10 is dressed even when the dress layer 16 is thick and the transmitted light amount tends to be low, or when the dressing abrasive grain content is high and the transparency of the dress layer 16 is low. A clear image can be taken without being blocked by the layer 16.

  Further, since the dress layer 16 is formed only in a narrow range on the division line 11, the amount of the liquid resin P2 used is smaller than that applied to the entire surface of the workpiece 10, which is advantageous in terms of cost. Furthermore, the dress layer 16 formed in the thin linear region is easier to control the contact state with the workpiece 10 than the dress layer formed widely in a plane, and is not intended before the cutting step. There is little possibility of peeling from the workpiece 10.

  As shown in FIG. 4, in the present embodiment, the width of the dress layer 16 in the Y-axis direction is set to be equal to or narrower than the width of the cutting blade 33 (thickness in the rotation axis direction). With this setting, when cutting the workpiece 10 with the cutting blade 33, the cutting blade 33 is cut into the entire width region of the dress layer 16 (see the enlarged portion L7 in FIG. 4), so that the cutting groove M is formed. At this stage, the cutting dress layer 16 is also completely removed (see the enlarged portion L8 in FIG. 4). That is, the cutting step for the workpiece 10 and the removal step for the dress layer 16 are performed simultaneously. Therefore, the process of removing the dress layer after the completion of cutting can be omitted, and the efficiency of the machining operation can be improved.

  The components of the dress layer (liquid resin), the shape of the dress layer, and the like in the present embodiment described above are merely examples, and the present invention is not limited thereto. Further, regarding the apparatus and jig used in each step of the dress layer forming step, the cutting step, and the dress layer removing step, it is possible to use different ones from the present embodiment.

  The processing method of the present invention may be applied to cutting performed by a single cutting device, or may be applied to cutting performed by a cluster module system configured by combining a plurality of processing devices including a cutting device. .

  Moreover, although each embodiment of the present invention has been described, as the other embodiment of the present invention, the above embodiment and modifications may be combined in whole or in part.

  The embodiments of the present invention are not limited to the above-described embodiments and modifications, and various changes, substitutions, and modifications may be made without departing from the spirit of the technical idea of the present invention. Furthermore, if the technical idea of the present invention can be realized in another way by technological advancement or another derived technique, the method may be used. Accordingly, the claims cover all embodiments that can be included within the scope of the technical idea of the present invention.

  As described above, according to the processing method of the present invention, a dress layer having an appropriate thickness according to the cutting edge amount of the cutting blade can be formed on the surface of the plate-like object, and the cutting edge amount of the cutting blade is limited. Even in this case, the cutting blade can be sharpened while cutting. Therefore, workability when cutting a plate-like object can be improved.

10 Workpiece (plate)
DESCRIPTION OF SYMBOLS 11 Dividing line 13 Dicing tape 14 Ring frame 15 Dress layer 16 Dress layer 20 Spinner table 22 Supply nozzle 24 Supply nozzle 30 Chuck table 31 Annular table 32 Clamp part 33 Cutting blade 34 Cutting water nozzle M Cutting groove
P1 Liquid resin
P2 Liquid resin W Cutting water

Claims (3)

A processing method of processing a plate-like object having a plurality of division lines formed on the surface along the division lines using a cutting blade,
A dress layer forming step for uniformly applying a liquid resin containing abrasive grains for sharpening the cutting blade on the surface of the plate-like material and curing the resin,
After performing the dress layer forming step, a cutting step of performing cutting with the cutting blade along the division schedule line while supplying cutting water;
A dress layer removing step for removing the dress layer after performing the cutting step;
A processing method characterized by comprising:   The processing method according to claim 1, wherein in the dress layer forming step, the dress layer is formed only on the planned division line. In the dress layer forming step, the dress layer is formed along the planned dividing line within a range equal to or narrower than the width of the cutting blade,
2. The processing method according to claim 1, wherein, in the cutting step, the cutting blade performs cutting along the planned dividing line and removes the dress layer.

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