JP2019081219A - Processing method for protective member - Google Patents

Abstract

To provide a new processing method for a protective member that can appropriately process a protective member made of resin.SOLUTION: A processing method for a protective member includes: a protective member attachment step of attaching an adhesive material layer side of a protective member 21 having an adhesive material layer formed on one surface of a base material 23 to a surface of a wafer 11; and a protective member processing step of processing the protective member 21 so that a thickness of the base material 23 becomes smaller by holding a rear surface side 11b of the wafer 11 with a holding surface 14a and rotating a grinding wheel 36 so as to bring grinding grindstones 40 into contact with the other surface side of the base material 23 of the protective member 21. In the grinding wheel 36, first grindstone groups constituted of a plurality of grinding grindstones 40 arranged so that distances thereof from a rotation center of the grinding wheel 36 gradually decrease toward a first direction along a circumferential direction of the grinding wheel 36 and second grindstone groups which are adjacent to the grinding stone 40 whose distance from the rotation center is smallest and include grinding grindstones 40 arranged so that distances thereof from the rotation center of the grinding grindstone 40 increase are arranged.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a method of processing a protective member for processing a protective member attached to a wafer.

  In an electronic device represented by a mobile phone or a personal computer, a device chip including a device such as an integrated circuit is an essential component. For example, the device chip divides the surface side of a wafer made of a semiconductor material such as silicon by a plurality of dividing lines (streets), forms a device in each area, and divides the wafer along the dividing lines. It is obtained by

  In recent years, there has been an increasing opportunity to thin wafers before division for the purpose of reducing the size and weight of device chips. For example, the wafer is ground from the back side by rotating a disk-shaped tool in which a plurality of grinding wheels formed by dispersing abrasive grains in a bonding material is fixed and the grinding wheels are brought into contact with the back side of the wafer. It can be thin.

  When grinding the back side of the wafer by the method as described above, a resin protective member called a protective tape is attached to the front side of the wafer, and the exposed side of the protective tape is held by a chuck table etc. There are many things to do. Thereby, it is possible to prevent the device formed on the surface of the wafer from being damaged by the load applied during grinding.

  By the way, the protection member made of resin is not necessarily formed in uniform thickness, and by simply sticking this protection member on the surface of the wafer, the thickness of the wafer after thinning by grinding tends to vary. Therefore, prior to grinding the wafer, a technique has been proposed in which the exposed surface of the protective member is ground to process the exposed surface of the protective member approximately parallel and flat to the back surface of the wafer (for example, Patent Document) 1 and 2).

Japanese Patent Application Laid-Open No. 61-141142 JP, 2005-19666, A

  However, when the protective member made of resin is ground with the above-mentioned grinding wheel, the grinding wheel is easily clogged by debris generated during grinding (grind). If the grinding wheel is clogged, the processing load increases and the protective member can not be properly processed.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a new processing method of a protective member which can appropriately process a resin protective member.

  According to one aspect of the invention, there is provided a grinding apparatus comprising a chuck table having a holding surface for holding a wafer, and a grinding unit for rotating a grinding wheel having a plurality of annularly arranged grinding wheels. A method of processing a protective member for processing a protective member attached to the wafer, comprising: a base formed of a material containing a resin; and an adhesive layer provided on one side of the base A protective member attaching step of attaching the adhesive material layer side of the protective member to the front surface of the wafer; holding the back surface side of the wafer by the holding surface; rotating the grinding wheel; And a protective member processing step of processing the protective member so that the thickness of the substrate is reduced by bringing the grinding wheel into contact with the other surface side of the grinding wheel. In the first direction along the circumferential direction Among the first grindstone group comprising a plurality of the grinding wheels disposed in such a manner that the distance from the center of rotation of the grinding wheel becomes smaller toward the other, and among the plurality of grinding wheels constituting the first grindstone group A second wheel group comprising the grinding wheel adjacent to the grinding wheel with the smallest distance from the center of rotation and positioned such that the distance from the center of rotation is greater than the grinding wheel with the smallest distance Are repeatedly provided along the circumferential direction, and in the protective member processing step, the chuck table and the grinding wheel are perpendicular to the rotation axis of the grinding wheel without rotating the chuck table. There is provided a method of processing a protective member that moves relative to one another.

  In the method of processing a protective member according to one aspect of the present invention, the method is applied to a wafer using a chuck table having a holding surface for holding the wafer and a grinding wheel having a plurality of annular grinding wheels. Process the protective member. The grinding wheel includes a first grinding wheel group comprising a plurality of grinding wheels arranged such that the distance from the center of rotation of the grinding wheel decreases in order in the first direction along the circumferential direction of the grinding wheel; One of a plurality of grinding wheels constituting the grinding wheel group is disposed adjacent to the grinding wheel having the smallest distance from the center of rotation, and is arranged such that the distance from the rotation center is larger than that of the grinding wheel having the smallest distance. A second grinding wheel group including a grinding wheel is repeatedly provided along the circumferential direction.

  Therefore, when processing the protective member by rotating the grinding wheel, the loads from the plurality of grinding wheels applied to the protective member can be dispersed, and clogging of the grinding wheel can be suppressed. Therefore, according to the processing method of the protection member concerning one mode of the present invention, the protection member made of resin can be processed appropriately.

FIG. 1 (A) is a perspective view schematically showing a configuration example of a wafer, and FIG. 1 (B) is a perspective view for explaining a protective member attaching process. It is a perspective view which shows typically the example of composition of the grinding device used at a protective member processing process. It is a bottom view which shows the structure of a grinding wheel typically. It is a partial cross section side view for demonstrating a protection member processing process. It is a bottom view which shows typically the structure of the grinding wheel which concerns on a modification.

  Embodiments according to one aspect of the present invention will be described with reference to the attached drawings. The processing method of a protection member concerning this embodiment includes a protection member pasting process (refer to Drawing 1 (B)), and a protection member processing process (refer to Drawing 4). In the protective member attaching step, a protective member made of a material such as resin is attached to the front side of the wafer. In the protective member processing step, the protective member attached to the wafer is processed and thinned. Hereinafter, the processing method of the protection member concerning this embodiment is explained in full detail.

  FIG. 1A is a perspective view schematically showing a configuration example of a wafer 11 used in the present embodiment. As shown in FIG. 1A, the wafer 11 is formed in a disk shape using a semiconductor material such as silicon (Si), for example. The surface 11 a side of the wafer 11 is divided into a plurality of areas by a plurality of dividing planned lines (streets) 13 crossing each other, and in each area, a device 15 such as an IC (Integrated Circuit) is formed.

  In the present embodiment, the disk-shaped wafer 11 made of a semiconductor material such as silicon is used, but the material, shape, structure, size, etc. of the wafer 11 are not limited. For example, a substrate made of a material such as ceramic, resin, metal or the like can be used as the wafer 11. Similarly, there is no limitation on the type, number, size, arrangement, etc. of the devices 15. Further, a substrate or the like on which the device 15 is not formed may be used as the wafer 11.

  In the method of processing a protective member according to the present embodiment, first, a protective member attaching step of attaching the protective member on the surface 11 a side of the above-described wafer 11 is performed. FIG. 1 (B) is a perspective view for explaining the protective member attaching process. The protective member 21 is formed, for example, in a circular shape having a diameter substantially equal to that of the wafer 11, and shows a film-like (flat plate) base 23 made of a material containing a resin and a predetermined adhesive force. And an adhesive layer 25 provided on one surface of the material 23.

  Therefore, as shown in FIG. 1B, the protective member 21 can be attached to the surface 11 a side of the wafer 11 by bringing the adhesive material layer 25 side of the protective member 21 into close contact with the surface 11 a side of the wafer 11. By attaching the protective member 21 to the front surface 11 a side of the wafer 11, the load, impact, and the like when grinding the rear surface 11 b side of the wafer 11 later are alleviated, and the device 15 formed on the front surface 11 a side of the wafer 11 Etc. can be protected.

  After the protective member attaching step, a protective member processing step of processing the protective member 21 attached to the wafer 11 is performed. FIG. 2 is a perspective view schematically showing a configuration example of the grinding apparatus 2 used in the protective member processing step. As shown in FIG. 2, the grinding device 2 includes a base 4 on which each component is mounted. The rear end of the base 4 is provided with a support structure 6 extending upward.

  In the upper surface of the base 4, an opening 4 a which is long in the X-axis direction (front-rear direction) is formed. A ball screw type X-axis moving mechanism 8 and a dustproof and drip-proof cover 10 covering a part of the X-axis moving mechanism 8 are disposed in the opening 4 a. The X-axis moving mechanism 8 includes an X-axis moving table 8a, and moves the X-axis moving table 8a in the X-axis direction. In front of the opening 4a, an operation panel 12 for inputting processing conditions and the like is installed.

  A chuck table 14 for holding the wafer 11 to which the protective member 21 is attached is provided on the X-axis moving table 8a. A part of the upper surface of the chuck table 14 is a holding surface 14 a for sucking and holding the wafer 11.

  The holding surface 14 a is generally flat and connected to a suction source (not shown) via a suction path (not shown) or the like formed inside the chuck table 14. The wafer 11 can be sucked and held by the chuck table 14 by placing the wafer 11 on the holding surface 14 a and applying a negative pressure of a suction source.

  The chuck table 14 moves in the X-axis direction together with the X-axis moving table 8 a by the above-described X-axis moving mechanism 8. In addition, the chuck table 14 may be connected to a rotational drive source (not shown) such as a motor. In this case, for example, the chuck table 14 can be rotated about a rotation axis substantially parallel to the Z-axis direction (vertical direction).

  A Z-axis moving mechanism 16 is provided on the front surface of the support structure 6. The Z-axis moving mechanism 16 includes a pair of Z-axis guide rails 18 generally parallel to the Z-axis direction. A Z-axis moving plate 20 is slidably attached to the Z-axis guide rails 18. A nut portion (not shown) is provided on the rear surface side (rear surface side) of the Z-axis moving plate 20, and a Z-axis ball screw 22 substantially parallel to the Z-axis guide rail 18 is screwed into this nut portion. ing.

  A Z-axis pulse motor 24 is connected to one end of the Z-axis ball screw 22. By rotating the Z-axis ball screw 22 by the Z-axis pulse motor 24, the Z-axis moving plate 20 moves in the Z-axis direction along the Z-axis guide rail 18. The front side (surface) of the Z-axis moving plate 20 is provided with a support 26 projecting forward.

  The support 26 supports a grinding unit (processing unit) 28 for processing the protection member 21 attached to the wafer 11. The grinding unit 28 includes a spindle housing 30 fixed to the support 26. A spindle 32 serving as a rotational shaft is accommodated in the spindle housing 30 in a rotatable state.

  The lower end (tip) of the spindle 32 is exposed to the outside of the spindle housing 30. At the lower end of the spindle 32, a disk-shaped wheel mount 34 is provided. On the lower surface of the wheel mount 34, a disc-like grinding wheel 36 having a diameter substantially the same as that of the wheel mount 34 is fixed by a bolt or the like.

  FIG. 3 is a bottom view schematically showing the structure of the grinding wheel 36. As shown in FIG. As shown in FIG. 3, the grinding wheel 36 according to this embodiment includes a disk-shaped (annular) wheel base 38 made of stainless steel, aluminum or the like. The wheel base 38 has an upper surface (not shown) generally parallel to the lower surface 38a and a lower surface 38a, and a generally circular opening 38b penetrating the base 38 from the upper surface to the lower surface 38a is formed in the center thereof. Further, on the lower surface 38a side of the wheel base 38, a supply port (not shown) for supplying a liquid (processing fluid) such as pure water downward is provided.

  When the grinding wheel 36 is attached to the grinding apparatus 2 described above, the upper surface of the wheel base 38 is brought into close contact with the lower surface of the wheel mount 34, and the wheel base 38 is fixed to the wheel mount 34 with a bolt or the like. That is, the upper surface of the wheel base 38 is a fixed end face in contact with the wheel mount 34 of the grinding device 2. On the other hand, the lower surface 38 a of the wheel base 38 is a free end surface not fixed to the grinding device 2.

  On the lower surface 38a of the wheel base 38, a plurality of grinding wheels 40 in which abrasive grains such as diamond or CBN (Cubic Boron Nitride) are dispersed in a bonding material such as resin or metal are annularly arranged and fixed. There are no particular restrictions on the type (material) of the bonding material that constitutes the grinding wheel 40, the material, size, shape, etc. of the abrasive grains, but in the present embodiment, the diamond abrasive grains are a bonding material of nickel (plating) Using the grinding wheel 40 fixed in FIG.

  The size, the number, and the like of the grinding stone 40 are appropriately set, for example, in accordance with the size and the like of the wheel base 38 and the protective member 21 (wafer 11). Further, in the present embodiment, as shown in FIG. 3, in the radial direction (r direction) of the wheel base 3, any two grinding stones 40 adjacent in the circumferential direction (θ direction) of the wheel base 38 Arrange in different positions.

  Specifically, the distance from the center 38c of the rotation of the wheel base 38 in the first direction (in the present embodiment, the θ + direction) along the circumferential direction of the wheel base 38 (the grinding wheel 36) is Adjacent to a first grinding wheel group 40e consisting of grinding wheels 40a, 40b, 40c, 40d arranged to be smaller and a grinding wheel 40d having the smallest distance from the center of rotation 38c, the center of rotation from this grinding wheel 40d A grinding wheel 40f arranged to increase the distance from 38c and a second grinding wheel group 40h consisting of a grinding wheel 40g adjacent to the grinding wheel 40f are repeatedly provided along the circumferential direction.

  That is, the grinding wheels 40a, 40b, 40c and 40d constituting the first wheel group 40e are arranged at positions far from the rotation center 38c in the order of the grinding wheels 40a, 40b, 40c and 40d. On the other hand, the grinding wheels 40f and 40g constituting each second wheel group 40h are arranged in the order of the grinding wheels 40f and 40g in positions closer to the center of rotation 38c. In the present embodiment, the first grindstone group 40 e and the second grindstone group 40 h are repeated six times along the circumferential direction of the wheel base 38.

  By arranging the plurality of grinding wheels 40 in this manner, the plurality of grinding wheels 40 can be brought into contact with a wide area of the protective member 21. That is, loads applied to the protective member 21 from the plurality of grinding wheels 40 are dispersed during processing. Thereby, clogging of the grinding stone 40 can be suppressed, and the protective member 21 can be processed appropriately.

  The plurality of grinding wheels 40 are disposed inside or outside of the grinding wheels 40 in the radial direction of the wheel base 38 and a part of the locus of any grinding wheels 40 formed during grinding. It is desirable to arrange so that a part of locus of another grinding wheel 40 may overlap. As a result, the trajectories of all the grinding wheels 40 are continuous, so there is a gap between the trajectory of one grinding wheel 40 and the trajectory of another grinding wheel 40, and the processing accuracy of the protective member 21 is reduced by this gap. It disappears.

  Specifically, as shown in FIG. 3, a part of the inside of the locus of the grinding wheel 40 a located at the outermost side in the radial direction (r direction) of the wheel base 38 is the grinding wheel located at the inner side in the radial direction It overlaps with a part of the outside of the 40b trajectory. Further, a part of the inside of the trajectory of the grinding wheel 40b overlaps a part of the outside of the trajectory of the grinding wheel 40g located more inside. Similarly, a part of the inside of the trajectory of the grinding wheel 40g overlaps a part of the outside of the trajectory of the grinding wheel 40c located inside.

  Furthermore, a part of the inside of the path of the grinding wheel 40c overlaps a part of the outside of the path of the inside of the grinding wheel 40f. Further, a part of the inside of the trajectory of the grinding wheel 40 f overlaps a part of the outside of the trajectory of the grinding wheel 40 d located at the innermost side in the radial direction. And as a result, the locus | trajectory of all the grinding stone 40a, 40b, 40c, 40d, 40f, 40g which comprises the 1st grindstone group 40e and the 2nd grindstone group 40h is united.

  In the present embodiment, the grinding wheels 40a, 40b, 40g, 40c, 40f and 40d are arranged in this order from the outside in the radial direction of the wheel base 38, but the arrangement of the plurality of grinding wheels 40 is this mode It is not limited to. For example, the grinding wheels 40a, 40g, 40b, 40f, 40c and 40d can be arranged in this order from the outside of the wheel base 38. The plurality of grinding wheels 40 may be arranged such that the trajectory of the grinding wheel 40b matches the trajectory of the grinding wheel 40g, and the trajectory of the grinding wheel 40c matches the trajectory of the grinding wheel 40f. Of course, a plurality of grinding wheels 40 may be arranged so that the trajectories do not overlap.

  Furthermore, in the present embodiment, the plurality of grinding wheels 40 are disposed with the θ + direction shown in FIG. 3 as the first direction, but a plurality of grinding wheels 40 may be disposed with the θ− direction as the first direction. Furthermore, in the present embodiment, the six first grindstone groups 40e each composed of four grinding wheels 40 and the six second grindstone groups 40h composed of two grinding wheels 40 are wheels. Although arranged on the lower surface 38a of the base 38, the number of the first grindstone group 40e and the second grindstone group 40h, the number of the grinding stone 40 constituting each first grindstone group 40e and each second grindstone group 40h, etc. There is no particular limitation on

  FIG. 4 is a plan view for explaining the protective member processing step. In the protective member processing step, first, the back surface 11b side of the wafer 11 is brought into contact with the holding surface 14a of the chuck table 14 described above, and a negative pressure of a suction source is applied to the holding surface 14a. Thus, the wafer 11 is sucked and held by the chuck table 14 so that the base 23 of the protective member 21 attached to the surface 11 a side is exposed upward.

  After suction and holding the wafer 11 by the chuck table 14, the grinding wheel 36 is rotated in a predetermined direction at a predetermined rotation number. At the same time, the grinding wheel 36 is lowered so that the height of the bottom surface of the grinding wheel 40 is lower than the other surface (upper surface) of the base 23 of the protective member 21. On the other hand, the chuck table 14 is not rotated.

  Then, the chuck table 14 is moved in the X-axis direction (that is, the rotation shaft of the grinding wheel 36) so that the grinding stone 40 contacts the base material 23 of the protective member 21 while supplying the liquid (processing liquid) from the supply port or the like. Move in the vertical direction). The rotation speed of the grinding wheel 36 is, for example, about 4000 rpm, and the supply amount of liquid is, for example, about 3.0 L / min to 7.0 L / min, and the moving speed of the chuck table 14 in the X axis direction is For example, about 0.1 mm / s to 0.5 mm / s. However, processing conditions are not limited to these.

  Thus, as shown in FIG. 4, the other surface side of the base 23 of the protective member 21 can be processed and thinned by the grinding stone 40. For example, when the exposed surface of the base 23 of the protective member 21 is substantially parallel and flat with the back surface 11 b of the wafer 11, the protective member processing step is finished.

  As described above, in the grinding wheel 36 of the present embodiment, the wheel base 38 is sequentially moved in the first direction (θ + direction) along the circumferential direction (θ direction) of the wheel base 38 (grinding wheel 36). First wheel group 40e consisting of a plurality of grinding wheels 40 (grind wheels 40a, 40b, 40c, 40d) arranged so as to reduce the distance from the center of rotation 38c, and the distance from the center of rotation 38c is the smallest A second grinding wheel group 40h including a grinding wheel 40f adjacent to the grinding wheel 40d and arranged such that the distance from the center 38c of rotation from the grinding wheel 40d is large is repeatedly provided along the circumferential direction. .

  Therefore, when processing the protection member 21 by rotating the grinding wheel 36, the loads from the plurality of grinding wheels 40 applied to the protection member 21 can be dispersed, and clogging of the grinding wheel 40 can be suppressed. Therefore, according to the processing method of the protection member concerning this embodiment, protection member 21 made of resin can be processed appropriately.

  Further, in the present embodiment, since the chuck table 14 and the grinding wheel 36 are relatively moved in the direction perpendicular to the rotation axis of the grinding wheel 36, the corner portion on the bottom side of the grinding wheel 40 is made of the protective member 21. The protective member 21 (base material 23) can be processed efficiently (effectively) by causing the base material 23 to cut into the material.

  After the protective member processing step, for example, a grinding step of grinding the back surface 11 b side of the wafer 11 may be performed. In this case, the wafer 11 can be ground using the grinding device 2 and the grinding wheel 36 described above, or the wafer 11 may be ground using another grinding device or grinding wheel.

  In the processing method of the protection member according to the present embodiment, since the protection member 21 can be appropriately processed, the thickness variation is caused by holding the protection member 21 side with a chuck table or the like and grinding the back surface 11b side of the wafer 11. Can be made thinner while suppressing the That is, the processing accuracy of the wafer 11 can be enhanced by incorporating the processing method of the protective member according to the present embodiment into the processing method (grinding method) of the wafer.

  The present invention is not limited to the description of the above embodiment, and can be implemented with various modifications. For example, although the grinding wheel 40 in which the abrasive grains of diamond are fixed by the bonding material of nickel is used in the above embodiment, a cemented carbide blade made of metal carbide or the like may be used as the grinding wheel 40. That is, abrasive grains need not necessarily be dispersed in the grinding wheel 40.

  Moreover, the protection member 21 can also be processed using the grinding wheel of the aspect different from the said embodiment. FIG. 5 is a bottom view schematically showing the structure of a grinding wheel 42 according to a modification. In addition, the basic structure of the grinding wheel 42 which concerns on this modification is as common as the grinding wheel 36 which concerns on the said embodiment.

  That is, the grinding wheel 42 according to the modification includes the disk-shaped (annular) wheel base 44 made of stainless steel, aluminum or the like. The wheel base 44 has an upper surface (not shown) substantially parallel to each other and a lower surface 44a, and a generally circular opening 44b penetrating the base 44 from the upper surface to the lower surface 44a is formed at the center thereof. Further, on the lower surface 44a side of the wheel base 44, a supply port (not shown) for supplying a liquid (processing fluid) such as pure water downward is provided.

  On the lower surface 44a of the wheel base 44, a plurality of grinding wheels 46 in which abrasive grains such as diamond or CBN (Cubic Boron Nitride) are dispersed in a bonding material such as resin or metal are annularly arranged and fixed. There are no particular limitations on the type (material) of the bonding material that constitutes the grinding wheel 46, the material, size, shape, etc. of the abrasive grains. Of course, abrasive grains need not be dispersed in the grinding wheel 46.

  The size, the number, and the like of the grinding stone 46 are appropriately set, for example, in accordance with the size and the like of the wheel base 44 and the protective member 21 (wafer 11). Also in the present modification, as shown in FIG. 5, any two adjacent grinding wheels 46 adjacent in the circumferential direction (θ direction) of the wheel base 44 are different in position in the radial direction (r direction) of the wheel base 3 It has been arranged.

  Specifically, the distance from the center 44c of the rotation of the wheel base 44 in the first direction (the θ + direction in this embodiment) along the circumferential direction of the wheel base 44 (grinding wheel 42) is Adjacent to the first grinding wheel group 46c consisting of grinding wheels 46a and 46b arranged to be small and the grinding wheel 46b having the smallest distance from the center of rotation 44c, the distance from the center of rotation 44c of the grinding wheel 46b The second grinding wheel group 46f including the grinding wheel 46d and the grinding wheel 46e adjacent to the grinding wheel 46d is repeatedly provided along the circumferential direction.

  That is, the grinding wheels 46a and 46b constituting each first wheel group 46c are arranged at positions far from the center of rotation 44c in the order of the grinding wheels 46a and 46b. The grinding wheels 46d and 46e constituting each second wheel group 46f are arranged at positions far from the center of rotation 44c in the order of the grinding wheels 46d and 46e. In the present embodiment, the first grindstone group 46 c and the second grindstone group 46 f are repeated nine times along the circumferential direction of the wheel base 44.

  Also in this case, a plurality of grinding wheels 46 can be brought into contact with a wide area of the protective member 21. That is, loads applied to the protective member 21 from the plurality of grinding wheels 46 are dispersed during processing. Thus, clogging of the grinding wheel 46 can be suppressed, and the protective member 21 can be appropriately processed.

  In addition, the structure, method, and the like according to the above-described embodiment can be appropriately modified and implemented without departing from the scope of the object of the present invention.

11 wafer 11a front surface 11b back surface 13 division lines (street)
15 device 21 protection member 23 base material 25 adhesive layer 2 grinding device 4 base 6 support structure 8 X axis movement mechanism 8a X axis movement table 10 dustproof drip-proof cover 12 operation panel 14 chuck table 14a holding surface 16 Z axis movement mechanism 18 Z axis guide rail 20 Z axis moving plate 22 Z axis ball screw 24 Z axis pulse motor 26 Support 28 Grinding unit (processing unit)
30 spindle housing 32 spindle 34 wheel mount 36 grinding wheel 38 wheel base 38a lower surface 38b opening 38c center of rotation 40, 40a, 40b, 40c, 40d, 40f, 40g grinding wheel 40e 1st wheel group 40h 2nd wheel group 42 grinding Wheel 44 Wheel base 44a Lower surface 44b Opening 44c Center of rotation 46, 46a, 46b, 46d, 46e Grinding wheel 46c 1st wheel group 46f 2nd wheel group

Claims (1)

A protection member attached to a wafer using a grinding apparatus comprising: a chuck table having a holding surface for holding a wafer; and a grinding unit for rotating a grinding wheel having a plurality of annularly arranged grinding wheels It is a processing method of the protection member to process,
Protective member attaching process for attaching the adhesive layer side of a protective member having a base formed of a material containing a resin and an adhesive layer provided on one side of the base to the surface of the wafer When,
The thickness of the substrate is reduced by holding the back side of the wafer with the holding surface and rotating the grinding wheel to bring the grinding wheel into contact with the other surface of the base of the protective member. A protective member processing step of processing the protective member to be
A first grinding wheel comprising a plurality of the grinding wheels disposed on the grinding wheel in such a manner that the distance from the center of rotation of the grinding wheel decreases in order in a first direction along the circumferential direction of the grinding wheel From the center of rotation of the group of grinding wheels adjacent to the grinding wheel with the smallest distance from the center of rotation among the grinding wheels constituting the first wheel group And a second grinding wheel group including the grinding wheel, which is disposed to increase the distance between the two grinding wheels, repeatedly provided along the circumferential direction,
In the protective member processing step, the protective member is characterized in that the chuck table and the grinding wheel are relatively moved in the direction perpendicular to the rotation axis of the grinding wheel without rotating the chuck table. Processing method.